MUHAMMAD SHAHBAZ QAMAR M.Sc. (Hons.) Animal Nutrition …prr.hec.gov.pk/jspui/bitstream/123456789/7962/1... · I am grateful to Professor Dr. Muhammad Sarwar, Distinguished National

1

USAGE OF ENZOSE (CORN DEXTROSE) AND CORN STEEP

LIQUOR (CSL) AS ENERGY AND PROTEIN SOURCE IN

BUFFALOES

By

MUHAMMAD SHAHBAZ QAMAR M.Sc. (Hons.) Animal Nutrition

95-ag-917

A Dissertation submitted in partial fulfillment of the

requirements for the degree of

DOCTOR OF PHILOSOPHY

IN

ANIMAL NUTRITION

Institute of Animal Sciences Faculty of Animal Husbandry

University of Agriculture,

Faisalabad

Pakistan 2015

2

DECLARATION

I hereby declare that the contents of thesis, “Usage of Enzose (Corn Dextrose) and Corn

Steep Liquor (CSL) as energy and protein source in buffaloes” are product of my own research

and no part has been copied from any published source (except the reference, standard

mathematical or genetic models/ formulae /protocols etc.). I further declare that this work has not

been submitted for award of any other diploma/ degree. The University may take action if the

information provided is found inaccurate at any stage.

Muhammad Shahbaz Qamar

3

To,

The Controller of Examinations,

University of Agriculture,

Faisalabad

We, the supervisory committee, certify that the contents and form of thesis submitted by

Mr. Muhammad Shahbaz Qamar, Regd. #. 95-ag-917 have been found satisfactory and

recommend that it be processed for evaluation by external examiner(s) for the award of degree.

SUPERVISORY COMMITTEE:

Chairperson _______________________________

(Dr. Mahr-un-Nisa)

Member _______________________________

(Prof. Dr. Muhammad Sarwar)

Member ________________________________

(Prof. Dr. Zia-ul-Rahman)

4

TO

MY LOVING & CARING

(WIFE)

DR. TAYYABA HUMA

5

ACKNOWLEDGEMENTS

All the praises and admirations are the sole prerogative of Allah Almighty, the creator of

this colorful universe, who granted me the vision and wisdom to unknot the mysteries of

knowledge in a more systematic manner that is termed as SCIENCE. And only by the grace of

Allah Almighty, I was able to make this material contribution to the existing ocean of

knowledge. I invoke Allah’s blessings and peace for my beloved Prophet Hazrat

MUHAMMAD (May Peace Be Upon Him), whose teachings and traditions are timeless beacon

of knowledge and wisdom for the entire humanity.

I am highly indebted to my supervisor, Dr. Mahr-un-Nisa, Associate Professor,

Department of Food Nutrition and Home Economics, GC University, Faisalabad for the

professional guidance and morale boosting during the whole tenure of this project. Despite her

hectic schedules I enjoyed her gracious company that especially made the research phase a

memorable stretch.

I am grateful to Professor Dr. Muhammad Sarwar, Distinguished National Professor,

Dean, Faculty of Animal Husbandry, University of Agriculture, Faisalabad who gave me an

opportunity to work at the farm and his laboratory as a post graduate student. I firmly believe this

study could never see its conclusion in the present form without having him as my mentor and

availing his generous and scholarly advice always on time.

I earnestly wish to record my heartfelt regards for Prof. Dr. Zia-ul-Rahman, Professor,

Institute of Physiology and Pharmacology, University of Agriculture, Faisalabad as member of

my supervisory committee for his affectionate behavior and unstinting guidance throughout the

course of my studies.

My warm appreciations and gratitude go for Dr. Asif Shahzad and Dr. Nasir Ali

Tauqir (Asstt. Prof., IANFT) for their right support, encouragement, constructive criticism and

guidance during numerous stalemates and tough hours of this project.

I feel highly obliged to all of my friends especially Dr. Nasir Mukhtar, Asstt. Prof.,

PMAS Arid Agriculture University, Mr. Muhammad Arif, Lecturer, Sargodha University, Mr.

Riaz Hussain Shah, Mr. Hashaam Adeel and Mr. Muhammad Aziz-ul-Rahman for their

friendly companionship, unceasing collaboration and the help they provided as and when needed.

The technical help rendered by Mr. Nazir Ahmad Kasana, Superintendent Lab and all

other staff members of the Depatment of Animal Nutrition is sincerely acknowledged.

The sacrifice made by all of my family members who religiously prioritized my studies

against everything on the domestic front and remained a source of comfort and solace for me,

will always be remembered.

Muhammad Shahbaz Qamar

Dated : 18-05-2015

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TABLE OF CONTENTS

Contents Page#

ACKNOWLEDGEMENT V

TABLES OF CONTENTS VI

LIST OF TABLES VIII

LIST OF FIGURES XI

List of Abbreviations

ABSTRACT

XII

Chapter 1 INTRODUCTION 1

Chapter 2 REVIEW OF LITERATURE 3

Feed byproducts 3

Common feed byproducts 5

Corn processing 10

Wet milling 10

Dry milling

Animal performance

11

15

Dry matter intake 15

Nutrient digestibility 20

Nitrogen balance 25

Growth performance

Meat characteristics

Dressing percentage

26

28

28

Carcass composition

Carcass mineral contents

29

29

Blood metabolites and hormones 30

Serum minerals 33

Hematology

Blood biochemistry

Thyroid hormones

33

35

36

Milk yield and composition 37

Milk urea nitrogen 40

Chapter 3 Influence of varying levels of corn steep liquor on

nutrient intake, nutrient digestibility and growth

response in growing Nili-Ravi buffalo calves

41

Abstract 41

Introduction 42

Materials and Methods 43

Results 45

Discussion 46

7

Chapter 4 Influence of varying levels of corn steep liquor on

nutrient intake, nutrient digestibility and growth response in growing Nili-Ravi buffalo calves

60

Abstract 60

Introduction 61


Results 64

Discussion 65

Chapter 5 Influence of varying levels of corn steep liquor on feed intake, nutrient digestibility, nitrogen balance, milk composition and blood biochemistry in early lactating Nili-Ravi buffaloes

78

Abstract 78

Introduction 79


Results 82

Discussion 84

Chapter 6 Influence of varying levels of corn steep liquor on feed intake, nutrient digestibility, nitrogen balance, milk composition and blood biochemistry in early lactating Nili-Ravi buffaloes

106

Abstract 100

Introduction 101


Results 104

Discussion 105

Chapter 7 Summary 120

Literature Cited 124

8

LIST OF TABLES

Tables Page#

Table 3.1 Ingredients and chemical composition of experimental diets

with varying levels of corn steep liquor fed to Nili Ravi

buffalo calves

52

Table 3.2 Effect of varying levels of corn steep liquor when replaced

with urea on nutrient intake and their digestibility in Nili

Ravi buffalo calves

53


with urea on growth performance, economic appraisal and

feed conversion ratio in Nili Ravi buffalo calves

54


with urea on hematological characteristics in Nili Ravi

buffalo calves

55


with urea on carcass characteristics in Nili Ravi buffalo

calves

56


with urea on half carcass separable primal cuts in Nili Ravi

buffalo calves

57


with urea on primal cuts with respective proportion of lean

meat, fat and bone (as %age of primal cut) in Nili Ravi

buffalo calves

58


with urea on mineral profile of meat in Nili Ravi buffalo

calves

59


with varying levels of enzose fed to in Nili Ravi buffalo

calves

70

Table 4.2 Effect of varying levels of enzose when replaced with corn

grains on nutrient intake and their digestibilities in Nili Ravi

buffalo calves

71


grains on growth performance in Nili Ravi buffalo calves

72


grains on carcass characteristics in Nili Ravi buffalo calves

73


grains on half carcass separable primal cuts in Nili Ravi

buffalo calves

74

Table 4.6 Effect of varying levels of enzose when replaced with corn 75

9

grains on primal cuts with respective proportion of lean

meat, fat and bone (as %age of primal cut) in Nili Ravi

buffalo calves


grains on mineral profile of meat in Nili Ravi buffalo calves

76


grains on hematological characteristics in Nili Ravi buffalo

calves

77


with varying levels of corn steep liquor fed to early lactating

Nili Ravi buffaloes

92


with urea on nutrient intake and their digestibility in early

lactating Nili Ravi buffaloes

93


with urea on nitrogen balance in early lactating Nili Ravi

buffaloes

94


with urea on hematological characteristics in early lactating

Nili Ravi buffaloes

95


with urea on blood mineral profile in early lactating Nili

Ravi buffaloes

96


with urea on blood biochemistry in early lactating Nili Ravi

buffaloes

97


with urea on thyroid hormone profile in early lactating Nili

Ravi buffaloes

98


with urea on weight gain, milk quantity and milk

composition in early lactating Nili Ravi buffaloes

99


with varying levels of enzose fed to early lactating Nili Ravi

buffaloes

112


grains on nutrient intake and their digestibility in early


113


grains on nitrogen balance in early lactating Nili Ravi

buffaloes

114

Table 6.4 Effect of varying levels of enzose when replaced with corn 115

10

grains on blood hematological characteristics in early



grains on blood mineral profile in early lactating Nili Ravi

buffaloes

116


grains on blood biochemistry in early lactating Nili Ravi

buffaloes

117


grains on thyroid hormone profile in early lactating Nili Ravi

buffaloes

118


grains on weight gain, milk quantity and milk composition

in early lactating Nili Ravi buffaloes

119

11

LIST OF FIGURES

Figures Page#

Figure 1 The ethanol production process (wet mill) 12

Figure 2 Schematic diagram of wet milling industry resulting in wet or

dry corn glutten feed

13

Figure 3 Schematic diagram of dry milling industry with the feed

products produced

14

12

List of Abbreviation

Sr. No. Symbol Abbreviation

1 AA Amino Acids

2 ADF Acid detergent Fiber

3 ADG Average daily gain

4 A/G Albumin : Globulin

5 ALP Alkaline phosphatase

6 ALT Alanine aminotransferase

7 AOAC Association of official analytical chemists

8 ARC Agricultural research council

9 BD Bilirubin direct

10 BI Bilirubin indirect

11 BT Bilirubin total

12 BUN Blood urea nitrogen

13 C Control

14 CF Crude fiber

15 CDGS Corn distiller's grain plus solubles

16 CGM Corn glutten meal

17 CM Canola meal

18 CP Crude protein

19 CSK Cotton seed cake

20 CSL Corn steep liquor

21 CSM Cotton seed meal

22 DCP Digestible crude protein

23 DDGS Dried distiller's grain plus solubles

24 DLC Differential leucocyte count

25 DM Dry matter

26 DMI Dry matter intake

27 DMRT Duncan's multiple range test

28 DP Dressing percentage

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29 E Enzose

30 EE Ether extract

31 FAO Food and agriculture organization

32 FCM Fat corrected milk

33 FCR Feed conversion ratio

34 FM Fish meal

35 GDP Gross domestic product

36 GIT Gastro intestinal tract

37 g Gram

38 GOP Government of Pakistan

39 Hb Hemoglobin

40 MCHbC Mean corpuscular hemoglobin concentration

41 MCP Microbial crude protein

42 MCV Mean corpuscular volume

43 MO Maize offal

44 N Nitrogen

45 NDF Neutral detergent fiber

46 NFE Nitrogen free extract

47 NPN Non-protein nitrogen

48 NRC National research council

49 OM Organic matter

50 PCV Packed cell volume

51 PKC Palm kernel cake

52 PKR Pak rupee

53 PUN Plasma urea nitrogen

54 RBC Red blood cell

55 RCBD Randomized complete block design

56 RFC Ready fermentable carbohydrates

57 RSM Rapeseed meal

58 SBM Soybean meal

59 SE Standard error

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60 SFM Sunflower meal

61 SGOT Serum glutamic oxaloacetic transaminase

62 SNF Solid not fat

63 SPSS Statistical package for social sciences

64 T3 Triidothyronine

65 T4 Thyrxine

66 TDN Total digestible nutrient

67 TRBC Total red blood cells

68 VFA Volatile fatty acid

69 WBC White blood cell

70 WCGF Wet corn glutten feed

71 WCW Warm carcass weight

72 WDGS Wet distiller's grain plus solubles

73 WO Wheat offal

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ABSTRACT

Four independent experiments were conducted to examine the influence of varying levels of corn steep

liquor (CSL) and enzose on feed intake, growth performance and carcass characteristics of growing nili-ravi male

buffalo calves and blood biochemistry, milk yield and its composition in early lactating nili-ravi buffaloes. In first

experiment, fifty male buffalo calves of 9 month old were randomly divided into five groups, 10 animals in each

group. Five isonitogenous (16% CP) and isocaloric (2.6 Mcal/kg) diets were formulated. The control diet (C) had

0% CSL and in CSL20, CSL40, CSL60 and CSL80 diets, 20, 40, 60 and 80% urea on nitrogen equivalent was

replaced by CSL, respectively. Animals fed CSL40 diets ate highest (3.33 kg daily) dry matter (DM) and this was

the lowest (3.16 daily) by those fed CSL40 diets. The neutral detergent fiber (NDF) and acid detergent fiber (ADF)

digestibility was higher (p<0.05) in animals fed diets containing CSL than those fed diet containing 0% CSL. Calves

fed CSL40 gained more (p<0.05) weight (757 g/day) than those fed CSL80 diet (637 g/day). Feed cost per Kg

weight gained was higher (PKR 80.79) in calves fed CSL0 diet; however feed conversion ratio was better in calves

fed CSL40 diet(4.89) than those fed CSL20, CSL60 and CSL80 diets. Pre slaughter weight of animals fed CSL40

diet was the highest (141.5 kg) and was the lowest (130 kg) in those fed CSL80 diet. Warm carcass weight was

higher (p<0.05) in animals fed CSL40 (65.8 kg) diet followed by those fed CSL60, CSL80, CSL20 and C diets.

Dressing percentage, skin, feet weight, and weight of all body organs remained unaltered across all diets. Similarly

primal cuts, ash, Na, K and Ca remained unchanged across all diets. The red blood cell count, white blood cells,

packed cell volume and hemoglobin values were also same across all diets. In second experiment, thirty five male

buffalo calves of 1 year old were randomly divided into five groups, 7 animals in each group. Five isonitogenous

(17.5% CP) and isocaloric (2.6 Mcal/kg) diets were formulated. The control diet (C) had 0% enzose and in E20,

E40, E60 and E80 diets, 20, 40, 60 and 80% corn on energy equivalent was replaced by enzose, respectively.

Animals fed control diet ate highest (7.65 kg/day) DM and was the lowest (7.39 kg/day) in animals fed E80 diets.

The NDF and ADF digestibility was higher in animals fed diets containing enzose than those fed C diet. The highest

NDF digestibility (61.8%) was observed in calves fed E40 diet whereas the lowest NDF digestibility (59%) was

noticed in calves fed control diet. Calves fed control gained more (p<0.05) weight (801 g/day) than those fed E80

diet (770 g/day). Feed cost per Kg weight gained was higher in calves fed E40 (PKR 109.32) diet and lowest in

calves fed E80 (PKR 79.62) diet; however feed conversion ratio was better in calves fed diets containing 80%

enzose (6.08) than those fed other diets. Pre-slaughter weights had been non-significant (p>0.05) across all treatment

groups. A significant difference in warm carcass weight was (p<0.05) observed. The highest value (91.8 kg) was

found in calves fed E80 diets and the lowest value (88.8 kg) was found in those fed E40 diet. Dressing percentage,

skin, feet weight, all body organs, primal cuts, lean, fat and bone proportion remained unchanged (p>0.05) across all

diets. The red blood cells, white blood cells, packed cell volume, hemoglobin and mineral profile of meat by claves

fed enzose diets remained unchanged (p>0.05) across all diets. In third experiment, twenty five early lactating

buffaloes were randomly divided into five groups, 5 animals in each group, using Randomized Complete Block

Design. Five isonitogenous (17% CP) and isocaloric (2.82 Mcal/kg) diets were formulated. The control diet (C) had

0% CSL and in CSL20, CSL40, CSL60 and CSL80 diets, 20, 40, 60 and 80% urea on nitrogen equivalent was

replaced by CSL, respectively. The DM and NDF digestibility were higher (p<.05) in animals fed diets containing

16

CSL than those fed C diet. Plasma urea nitrogen (PUN) was lowest in buffaloes fed CSL80, CSL60 and CSL40 diets

and was highest in buffaloes fed C diet. Nitrogen balance remained significant (p<0.05) higher in buffaloes fed CSL

diets as compared to those fed C diet. The blood urea, alanine aminotransferase (ALT), albumin:globulin (A/G),

bilirubin direct (BD) and bilirubin indirect (BI) values remained unchanged (p>0.05) across all diets. The creatinine,

alkaline phosphatase (ALP), serum glutamic oxaloacetic transaminase (SGOT), total protein, albumin, globulin and

bilirubin total (BT) value were higher (p<0.05) in animals fed CSL60 and CSL80than those fed C, CSL20 and

CSL40 diets. The triiodothyronine (T3), thyroxine (T4) and their ratio remained unchanged (p>0.05) across all diets.

Milk production, its fat, protein, true protein, non-protein nitrogen (NPN) and solid not fat values remained

unaltered across all diets. The 4% fat corrected milk and lactose were higher (p<.05) in milk of buffaloes fed

CSL40, CSL60 and CSL80 diets than those fed CSL20 and C diets. In fourth experiment, twenty five early lactating

buffaloes were randomly divided into five groups, 5 animals in each group, using Randomized Complete Block

Design. Five isonitogenous (17% CP) and isocaloric (2.82 Mcal/kg) diets were formulated. The control diet (C) had

0% enzose and in E20, E40, E60 and E80 diets, 20, 40, 60 and 80% corn on energy equivalent was replaced by

enzose, respectively. The NDF intake by buffaloes was higher (p<0.05) in animals fed C diets followed by those fed

E40, E20, E60 and E80 diets, respectively. The DM, NDF and ADF digestibility was higher (p<0.05) in buffalos fed

E80 and E60 diets than those fed E40, E20 and C diets, respectively. Plasma urea nitrogen and nitrogen balance was

higher (p<0.05) in buffaloes fed E80 and E60 diets than those fed E40, E20 and C diets, respectively. The blood

urea, creatinine, ALT, A/G and BD also remained unaltered (p>0.05) across all diets. However, ALP, SGOT, total

protein, albumin, globulin, BT and BI were higher (p<0.05) in animals fed E60 and E80 diets followed by those fed

E40, E20 and C diets, respectively. The T3, T4 and their ratio remained unchanged (p>0.05) across all diets. Milk

production, its fat, protein, true protein, NPN and SNF remained unaltered across all diets. However, 4% FCM and

lactose remained higher in animals fed E80 and E60 diets followed by those fed E40, E20 and C diets, respectively.

In conclusion, increased nutrient ingestion, utilization and weight gain by calves reflect the suitability and potential

of enzose and CSL as an economical energy and protein sources when used to replace corn grains at a level of 80%

and urea at a level of 40%, respectively. Similarly, buffaloes fed enzose and CSL supplemented diets had higher

nutrient intake and digestibility. The animals had better nitrogen balance, blood biochemistry, hormonal profile and

they produced milk with better quantity and quality when fed enzose and CSL in their diets.

17

CHAPTER 1 INTRODUCTION

Livestock sector has a share in national economy worth mentioning and provides quality

food items to ever increasing human population of Pakistan (Tauqir et al., 2012). This sector,

with 172.2 million heads, accounts for 55.4% of agricultural GDP and 11.9% of total GDP

(Economic Survey of Pakistan, 2013). More than 34 million rural population is engaged in

livestock sector for its livelihood (Sarwar et al., 2002a, b). Total average milk production in our

country is more than 45 billion liters (Economic Survey of Pakistan, 2013). Foreign exchange

earnings from livestock sector are more than 53 billion rupees (PKR) which account for 11% of

overall country’s foreign exchange earnings (Ahmad et al., 2010). Milk accounts for 51% of

total value of livestock sector (Sarwar et al., 2002 b). Meat industry of Pakistan is also growing

and the export of meat has increased from 108.54 to 123.61 million (USD) from 2010 -2011 to

2011-2012 with a growth of 13.9% (Anonymous, 2013). The meat productivity can be enhanced

if animals are properly fed.

In Pakistan, the area under fodder crops is only 2.46 million hectares, with a forage

production of 55.06 million tons giving an average yield of 22.38 ton per hectare (GOP, 2009b).

This forage production is insufficient to meet the requirements of ever increasing livestock

population. Livestock are getting only 62 and 74% of the required crude protein and total

digestible nutrients, respectively (Sarwar et al., 2002a, b). Strong competition with cash crops is

further decreasing fodder cultivation area (2% per decade) which threatens the nutrients

availability for livestock (Sarwar et al., 2002).

The livestock are mainly fed fodder crops, shrubs, grasses and agroindustrial byproducts.

Most of them are also low in protein, minerals, energy, and digestibility and high in fiber

(Sindhu et al., 2002). Due to low energy, protein, minerals and digestibility, they couldn’t

narrow down the gap between nutrient availability and supply. Under these circumstances, the

ruminant livestock production cannot be raised successfully unless we make sufficient feed

available for them. It could only be enhanced through adding some more feed byproducts in the

national feed inventory. A lot of feed ingredients have already been nutritionally evaluated and

are being used in ruminant feeding.

There are two potential feed byproducts viz; corn steep liquor (CSL) and enzose which

seems promising provided they are nutritionally evaluated. The CSL is high in protein (40%)

18

which makes it an excellent protein source for ruminant animal feeds (Nisa et al., 2004). Enzose

is a liquid derived from the enzymatic conversion of corn starch to dextrose. Unlike other

fermentable sugars, enzose has high lactic acid content and is a cheaper source of dextrose (Khan

et al., 2004). Enzose contains 85% dextrose, with a pH ranging from 3.5 to 4.5.

A lot of research work have been done on the nutritional worth and usage of molasses

(Hassan et al., 2011), rice polishing (Garcia et al., 1992), wheat bran (Khan et al., 1992), oil

cakes (Younas et al., 2005), meals (Tauqir et al., 2013) and hulls (Sarwar et al., 1992). The use

of these feed byproducts has reduced the feeding cost of animals while maintaining their

productivity (Sindhu et al., 2002). However, CSL and enzose could prove very good source of

nitrogen and energy if their nutritional worth is determined. However, the scientific evidence

regarding the influence of feeding high level of dietary CSL and enzose on animal productivity is

limited. Therefore, the present study was planned to evaluate the effect of gradual replacement of

urea by CSL and corn grains by enzose on nutrients intake and their digestibility, weight gain,

feed conversion ratio, carcass and meat characteristics of fattening male buffalo calves and milk

yield and its composition in lactating buffaloes.

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CHAPTER 2 REVIEW OF LITERATURE

Feed byproducts

The area under fodder crop cultivation in Pakistan is about 16% of the total cropped area

which has been decreasing about 2% for each decade (Sarwar et al., 2002) due to rapid

urbanization and more pressure on cash crops. Because of this situation, availability of fodder in

sufficient quantity is limited and that is why our livestock are getting only 75% of the required

amount of total digestible nutrient (TDN) and 40% of their digestible crude protein (CP)

requirement (Akram, 1990) and hence are under fed. There are many options to overcome this

fodder shortage but one of them is the use of agro industrial feed byproducts (Sindhu et al.,

2002). Ruminants are generally raised on natural pasture and crop residues which are low in

protein, fermentable energy and other nutrients (Adugna and Sundstol, 2000). This results into

low animal productivity because of reduced feed intake, digestibility, fermentation, and

microbial nitrogen. Unless we improve inherent poor nutritive characteristics of these feed

resources (Nsahlai et al., 2000; Adugna and Sundstol, 2000), the animal productivity cannot be

improved.

Nutrient requirements of livestock in developing countries are mainly met through fodder

crops, shrubs and other agro industrial byproducts. The nutritional potential of some feed

byproducts has been determined but there are many more whose nutritional potential is yet to be

harnessed (Sarwar et al., 2003). There are many feed byproducts which are used in animal feeds

but the most important of them include palm kernel cake (PKC), cotton seed cake (CSK), cotton

seed meal (CSM), sunflower meal (SFM), corn glutten meal (CGM), canola meal (CM), soybean

meal (SBM), rapeseed meal (RSM), maize offal (MO), wheat offal (WO) and cassava peels.

Feed byproducts are quite abundant and are of varied nature (Sindhu et al., 2002) and they fulfill

maintenance requirements of animals (Sarwar et al., 2002). Livestock are getting 50.7, 37.85,

6.10, 2.35 and 3% of their total nutrients requirements from crop residues, fodders, cereal by

products, oilcakes and other wastes, respectively (Crowder, 1988). Hanjra et al. (1995) reported

that animals in Pakistan were getting 51, 38, 3, 6, and 2% of their nutrient from fodders and crop

residues, rangeland, post-harvest grazing, cereal by products and oil cakes, respectively.

20

Feed resources such as cereal grains and concentrates are hardly feasible for animal

feeding in Pakistan due to their high price and competitive supply for human consumption

(Tauqir et al., 2012). The energy and protein status of low quality feedstuffs can be enhanced

with the supplementation of concentrates (Galloway et al., 1993). This is, however, a costly

approach for resource poor farmers. It means that an alternative system is required to employ

those feed ingredients which do not have any direct human value (FAO, 2004). In order to

increase profitability and reduce the demand for cereals, an alternative approach may be the

replacement of concentrates with cheaper agro industrial byproducts. So it is imperative to

explore new livestock feed resources like corn byproducts, which could be utilized efficiently for

animals feeding (Tauqir et al., 2012).

Agro industrial feed byproducts refer to byproducts derived in the industry due to

processing of main products (Aguilera, 1989). They may also be defined as the products arising

from the processing of crops or animal product usually by an agricultural industry (Onwuka et

al., 2012). The resultant products from these industries are of little or no nutritional importance

for human beings. They are considered to be a good source for increasing the animal productivity

(Onwuka et al., 2012). The byproducts of agro industries are much more concentrated, highly

nutritious and less costly as compared to crop residues (Aguilera, 1989). Agro industrial

byproducts have been widely used as energy and protein supplements. The use of these

conventional agro industrial byproducts has been limited by periodic shortages and ever

increasing cost (Mekasha et al., 2003). Keeping in view that fact, it is the need of time to explore

new non-conventional agro industrial byproducts which have good nutritive value and are

available at lower cost around the year. The use of these byproducts is beneficial for livestock

feeding when the forage supply is inadequate for the animal’s needs, either in terms of quantity

or quality. Feeding agro industrial byproducts will help decrease feeding cost which will

ultimately reduce the cost of production. The BDG, MO, and WO are byproducts of sorghum,

maize and wheat processing, respectively. They are of low protein and high crude fiber contents.

These two factors limit their use in monogastric animals. However, ruminants, because of their

ability to digest low quality feeds and roughages, can utilize these products more effectively and

efficiently than monogastric animals. By this way, they are no more in competition for human

feed resources. The supply of these byproducts is considerably high but their rate of utilization

21

depends on the chemical composition as well as the species of livestock. Wheat bran/offal are

considered the most common followed by fresh or wet brewers' grains (Onwuka et al., 2012).

This review describes the common classification of feed byproducts and their impact on

nutrient intake, nutrient digestibility, rumen characteristics, weight gain, milk yield, carcass

characteristics, blood picture, blood metabolites, hormones and enzymes, wool characteristics,

blood urea nitrogen and nitrogen balance in the following paragraphs.

Common feed byproducts

Feed byproducts can be classified according to their energy, protein and mineral contents

(Onwuka et al., 2012). The energy sources are rich in fermentable carbohydrates and low in

protein. The best examples of energy sources are molasses and enzose. Molasses is a cheaper

source of energy and is a byproduct of sugar industry (Sindhu et al., 2002). Enzose is a

byproduct of the wet corn milling industry. It is a liquid derived from the enzymatic conversion

of corn starch to corn dextrose (Khan et al., 2004). Protein supplements refer generally to those

ingredients that contain more than 20% crude protein (Onkuwa et al., 2012). Agro industrial

byproducts that serve as protein sources are mostly the oilseed cakes. They include CSM, CM,

SFM, SBM, corn glutten 30% and corn glutten 60%. Oilseed cakes, especially CSC is the most

abundant compared to rest of oil seed cakes in the country (Sindhu et al, 2002). Groundnut cake

is also important but its production declined drastically in last three decades. There are some

other miscellaneous byproducts including wheat bran, other brans from traditional grains like

sorghum, millet, rice and maize, brewers' grains, citrus pulp, sugar beet pulp, tomato pulp etc.

The mineral sources primarily supply minerals and are commonly from animal byproducts. The

example is bone meal and oyster shell (Onkuwa et al., 2012). There are some other non-protein

nitrogen sources which are included in normal diet formulation of ruminants. They include urea

and CSL. The CSL is a byproduct of the wet corn milling industry and is high in protein which

makes it an excellent protein source for ruminant animal feeds. It is a cost effective feed

byproduct which can easily replace other non-protein nitrogen sources keeping. Its crude protein

contents are 40% and is an excellent source of essential amino acids, peptides, organic

compounds, magnesium, phosphorous, calcium, potassium, chloride, sodium, sulfur and myo-

inositol phosphates (Hull et al., 1996).

22

Cereal byproducts

Cereal bran

This is the outer covering of grains separated during processing. It is obtained from the

milling of wheat, maize or rice. Wheat bran has been the most important cereal bran in Pakistan

since long. Brans contain 9-18% CP and 10-14% crude fiber (CF). They have a laxative action in

the gut and because of their high fiber content; they can be used as nutrient diluents in

monogastric animals. Usually, the amino acid profile of bran protein is superior to that of the

whole grain. The phosphorous content of bran is quite high but they are low in calcium. The

byproducts which can be used as nutritious cattle feed also include the husk of pods from some

cereals with leaves and remaining tender stems. They are very good source of digestible protein

(Ranjhan, 1993) and may be fed to livestock along with the concentrate mixture (Bhatti & Khan,

1996).

Wheat bran is a commonly used product in formulating feed for dairy animals in

Pakistan. It contains about 10% digestible crude protein (DCP), 65% TDN, 0.07% Ca and 0.35%

P. It can also be fed to sick animals without any deleterious effects on their health status. It

produces laxative effect in the intestine (Verma, 1997). It can be incorporated up to 50% of the

total ration for young calves. Bran has amino acid balance superior to that of whole wheat and

high in P but low in Ca. They are good sources of water soluble vitamins, except niacin (Cheeke,

1991). Wheat middling is similar to wheat bran except that they have lower fiber and higher

flour contents. Due to this fact, they have higher contents of digestible energy as compared to

wheat bran. Wheat middling contains 10-14% CP and 9.5% CF (Cheeke, 1991).

The chemical composition of rice husks depicts that it contains 8 to 11% water, 15.6 to

22.6% ash, 14.5 to 17.5% acid insoluble ash, 2.9 to 3.6% CP, 0.8 to 1.2% ether extract (EE), 39

to 42% CF and 25 to 29% nitrogen free extract (NFE). It is interesting to note that rice husk is

not palatable as such (Ranjhan, 1993) and should be used as a part of ration (Deschard et al.,

1988). Feeding of rice bran alone may result in colic pain due to formation of ball inside the

intestine. Hence, it should always be mixed with other concentrates before feeding it to the

animals. It contains 7% DCP, 65% TDN, 0.06% Ca and 1.12% P. It is rich in vitamin B

complex. It may be used for feeding cattle, buffaloes, sheep and goat (Verma, 1997).

Rice bran is a major feeding stuff in tropical countries. It is high (13%) in oil content

(Cheeke, 1991). Rice polish contains about 3% CF, 12% EE and 12 to 14% CP. It is an excellent

23

source of energy and is rich in vitamin B complex. It is considered to be a good feed for

livestock. However, maize gluten feed is rich source of protein (45 to 48%) and very useful for

livestock feeding (Verma, 1997).

Cakes and meals

Oil seed cakes and meals are the residues remaining after removal of the greater part of

the oil from oil seeds. The residues are rich in protein and most of them are valuable feeds for

farm animals. They often serve as protein supplements. Most oil seeds are of tropical origin, they

include groundnut, cottonseed, canola, soybeans and palm kernel. Others plant protein sources

that are less frequently used include coconut meal, rapeseed meal, rubber seed meal, sesame

cake.

Soybean is the most widely used oil seed protein and as such is considered as reference

protein (Onkuwa et al., 2012). The commonest form of soybean feeding is soybean meal.

Soybean meal has about 40-48% CP depending on the efficiency of oil extraction and whether or

not the beans were dehulled (Ishler & Varga, 2010).

The CSC is obtained from cotton seed after the removal of the lint, followed by oil

extraction from the seed. It has a CP content of 22- 24% depending on the efficiency of oil

extraction (Ahmad et al., 2004). It is high in fiber containing about 10-13%. It is deficient in

lysine, methionine, leucine and isoleucine. The CSC also contains various anti-nutritional factors

which includes gossypol. The nutritional value of CSC can be enhanced by several techniques

which include decorticating, dehulling, removal of gossypol by extracting the meal with a

mixture of hexane, acetone and water. In Pakistan, most of the CSC is used in the feeding of

ruminants and ruminants can utilize the CSC without dehulling (Tauqir et al., 2012). The PKC is

a product of oil palm processing. It is obtained after oil extraction from palm kernel. Its CP

contents are between 18-25%. The PKC is deficient in lysine, methionine, histidine and

threonine (Chanjula et al., 2010). The PKC is gritty and high in fiber content (at least 9%).

The SFM is produced from sunflower seed following oil extraction by either solvent or

mechanical methods. The CP content ranges from 41-47%. It is highly deficient in lysine,

tyrosine, methionine and cystine. It is high in CF (11-13%). While decorticated sunflower meal

can be fed to all classes of livestock, the use of undecorticated meal should be restricted to

ruminants. SFM is high in calcium and phosphorus (Onwuka et al., 2012).

24

The CGM is a byproduct of corn wet milling. It has low CF (2.4%) and high CP content

(67.1% on DM basis). The CP and certain essential amino acids make it a valuable protein

source for poultry, fish, and companion animal food industries. The CGM has relatively high

phosphorous concentrations (0.54%), compared to many typical animal diet ingredients (Rausch

and Belyea, 2006). Most non-ruminants (poultry) have high phosphorous requirements;

therefore, high phosphorous concentrations in CGM are an advantage. However, high

phosphorous content could be a concern in some dietary situations because of the potential to

increase phosphorus in animal wastes and waste disposal difficulties. The CGM also has high

sulfur content (0.70%). When CGM is included in a ruminant diet, the Sulfur concentration of

the resulting diet will be low and would not be expected to have adverse effects. However, high

sulfur concentrations can occur when there are excessive concentrations of certain Sulfur-

containing amino acids. The high sulfur concentration of CGM is not associated with these

amino acids and does not appear to pose a practical concern. The CGM has other unique

characteristics. It can impart a bitter taste to diets; animals may hesitate to consume diets

containing CGM, unless included in small proportions or masked by more palatable ingredients

(Rausch and Belyea, 2006). The concentration of xanthophyll in CGM has been reported to

range from 322 to 482 mg/kg (Wright, 1987). Because of these concentrations, CGM often is

added to poultry diets to improve pigmentation of poultry products. (Rausch et al., 2006).

The CGF is another byproduct of wet milling. The protein content of CGF (25.6%) is

greater than most common animal dietary ingredients such as corn. Due to this reason, it is a

widely used ingredient in ruminant production diets (Rausch and Berlea, 2006). The CP in CGF

contains a large soluble fraction (69%), compared with the soluble fraction in corn and DDGS

(34 and 33 %, respectively) (Krishnamoorthy et al., 1982). Therefore CGF should be minimized

in diets that contain other dietary ingredients with high soluble protein concentrations, such as

silages. CGF is characterized by high fiber content (45 % cell wall), which limits its use to

ruminant diets. While CP content makes CGF an attractive ingredient, high phosphorous content

(0.82%) is a concern. Most ruminant production diets contain adequate phosphorous

concentrations. By adding CGF at a level of 10%, there would be an increase in the phosphorous

content of the diet. When ruminants consume diets containing elevated concentrations of

phosphorus, excretion of phosphorus is increased (Morse et al., 1992). This can create disposal

25

challenges, because environmental regulations on phosphorous concentration are becoming more

restrictive (Spears et al., 2003).

Corn germ meal is produced from whole germ following hexane extraction. It is

characterized by relatively high CF (13.1%) contents and moderate concentrations of CP (11.5%)

and EE (7.7%). Germ meal is considered a highly desirable ingredient for non-ruminant diets

because of essential amino acid concentrations. There are limited contemporary published data

on the characteristics of corn germ meal and on the performance of animals consuming diets

containing this byproduct (Wright, 1987).

Sugar industry byproducts

Molasses is the readily available source of fermentable carbohydrates. It is an excellent

source of energy for livestock and poultry. The urea molasses based diets can very successfully

be fed as a sole ration with little protein supplement and forage to growing calves and lactating

animals (Ranjhan, 1993). In a concentrate mixture, inclusion of 10 to 15% molasses increases the

palatability of the concentrate mixture (Verma, 1997). It contains 20.6% water, 60.8%

fermentable sugars, 3.2% CP, 2.2% soluble gums, 8.2% ash and 5.0% free acids. The effect of

liquid urea molasses diet on the reproductive performance was thoroughly studied by Pathak

(1973) and found no ill effect on semen quality of bulls. Molasses has also been used as binding

agent with urea. Molasses provides the major source of fermentable carbohydrates (Cheeke,

1991). Sugarcane tops are palatable and cattle can be maintained entirely on them with a little

supplement of concentrate mixture or leguminous feeds (Verma, 1997). Sugarcane tops can be

converted into a good quality silage or hay for feeding during scarcity period of fodder.

Sugarcane tops with or without leaves have a good feeding value and are readily accepted by

ruminants either fresh, dried or ensiled (Tariq, 1988; Bhatti & Khan, 1996). Sugarcane bagasse is

a good source of cellulose but is poor in CP (1.3%) and high in lignin (16%). It has been used

successfully as roughage for ruminants. High pressure treatment improves the palatability and

digestibility of bagasse (Morrison & Brice, 1984). However, digestibility of unprocessed bagasse

is low because it contains high lignin contents (Bhatti & Khan, 1996). It can be fed up to a level

of 4 kg to adult cattle for maintenance after chaffing it. It may be fed by mixing with molasses

and wheat bran for good performance of animals. Press mud can be used in the formulation of

livestock feed because it has a higher CP content than molasses and contains more soluble

calcium, which is an important constituent of animal feed (Benerjee, 1993). Condensed molasses

26

soluble/dried yeast sludge is a byproduct of various fermentation processes in which large

quantity of molasses is used to produce alcohol, yeast, citric acid, monosodium glutamate, etc.

This product is a rich source of microbial protein and is useful ingredient of animal feed. After

condensation to 65 to 75% DM, it is called the condensed molasses solubles (Cheeke, 1991).

Corn Processing

Corn milling byproducts are expected to replace traditional vegetable protein sources in

Pakistan. Two types of milling processes currently exist, resulting in quite different feed

products. The dry milling process produces distillers grains plus solubles, and the wet milling

process produces corn gluten feed, CSL and enzose. These feeds can be marketed as wet feed, or

they can be dried and marketed as either dry corn gluten feed or dry distillers grains with or

without solubles (Onkuwa et al., 2012). The majority of dry milling plants produce wet distiller’s

grains plus solubles (WDGS). These products are very attractive for ruminant animals to use as

an energy source. There are two most commonly used techniques for processing of corn namely,

wet milling and dry milling.

Wet Milling

Wet milling is a process that uses the corn which results in numerous products for human

use. During this process, corn is “steeped” and the kernel components are separated into corn

bran, starch, corn gluten meal (protein), germ, and soluble components. Wet corn gluten feed

usually consists of corn bran and steep, with germ meal added if the plant has those capabilities.

Dry corn gluten feed contains less energy than wet corn gluten feed (Ham et al., 1995) when fed

at high levels in finishing diets. The quality of wet corn gluten feed (WCGF) varies depending

on the nature of processing plant. Steep liquor contains more energy and protein than corn bran

or germ meal (Scott et al., 2003). Therefore, the processing plants that apply more steep to corn

bran or germ meal will produce WCGF that is higher in CP and energy.

Dry Milling

In the dry milling process, the feed products produced are distillers grains, distillers

grains plus solubles, and distillers solubles. Depending on the nature of the plant and whether it

is producing wet or dry feed, the relative amounts of distillers grains and distillers solubles

mixed together varies (Rausch and Belyea, 2006). However, on dry matter basis, wet distillers

grains plus solubles are approximately 65% distillers grains and 35% distillers solubles (Onkuwa

27

et al., 2012). Distiller grains plus solubles are referred to as either WDGS or DDGS. The distiller

grains may be containing some solubles, but this can vary from plant to plant. The dry milling

ethanol process is relatively simple where corn (or another starch source) is ground, fermented,

and the starch is converted to ethanol and CO2 (Rausch and Belyea, 2006). Approximately 1/3 of

the DM remains as the feed product following starch fermentation assuming that starch source is

approximately 2/3 starch. As a result, all the nutrients are concentrated 3-fold because most

grains contain approximately 2/3 starch. For example, if corn has 4% oil, the WDGS or dry

distillers grains plus soluble (DDGS) will contain approximately 12% oil. The wet milling

industry is more complex and the corn kernel is divided into more components for higher value

marketing. For example, the oil is extracted and sold in the wet milling industry as is the corn

gluten meal, a protein supplement that contains a large amount of bypass protein, or UIP,

commonly marketed to the dairy, poultry, or pet industries. The importance of understanding the

process is that the resulting feed products from these two industries are quite different based on

how they are produced (Clevenger et al., 2004).

The majority of the research on distiller grains as an energy source has been conducted

on finishing cattle. Feeding WDGS results in better performance than DDGS. Experiments

evaluating the use of wet distillers byproducts in ruminant diets are available (DeHaan et al,

1982; Farlin, 1981; Firkins et al., 1985; Fanning et al., 1999; Larson et al., 1993; Trenkle, 1997a;

Trenkle, 1997b; Vander Pol et al., 2005a). In the experiments with finishing cattle, the

replacement of corn grain with wet distillers byproduct consistently improved feed efficiency.

The experiments suggest a 15 to 25% improvement in feed efficiency when 30 to 40% of the

corn grain is replaced with wet distiller byproduct.

28

Figure 1 Ethanol Production Process (Wet Mill)

CORN Steeping

Grinding

Scrrning Starch-Gluten

Separation Starch

Germ

Separation

Germ

Oil Refining

Fiber

Wet Gluten

Drying

Fermentation

Dextrose

Syrup

Refining

Corn

Syrup

Corn Oil Feed Product

Wet Feed

Only 60% Protein

Gluten Meal Starches

Ethanol Chemicals

High Fructose

Corn Syrup

University of Nebraska, Lincoln, 2012

29

Figure 2 Schematic diagram of wet milling industry resulting in wet or dry

corn gluten feed.

STEP CORN

SLEEP GRIND WASH WATER

SEPARATION

STARCH, SWEETENER, ALCOHOL

GLUTEN MEAL

CORN OIL

CORN BRAN WET CORN GLUTEN FEED

DRY CORN GLUTEN FEED


GERM MEAL, SCREENINGS,

DIST SOLUBLES

30

Figure 3 Schematic d i a g r a m of the dry milling industry with the feed

products produced.

CORN, GRAINS

GRIND, WET, COOK

FERMENTATION

YEAST, ENZYMES

STILL ALCOHOL & CO2

STILLAGE

DISTILLERS GRAINS DISTILLERS SOLUBLES

WDG, DDG WDGS

DDGS


I

Animal performance

Feed byproducts especially enzose and corn steep liquor seem to have a value as

ingredients in finishing cattle diets. Most of the value is from the nutrients contained in steep

liquor (Trenkle & Ribeiro, 2002). The 6%, improvement in feed efficiency, though statistically

nonsignificant, might have resulted from increased moisture content of the total mixed diet or

from beneficial effects on fermentation and digestion of feed in the rumen and digestive tract.

The following paragraphs will demonstrate the effect of feed byproducts on dry matter intake,

nutrient digestibility, nitrogen balance, growth performance, carcass composition, carcass

characteristics, dressing percentage, blood metabolites, hormones and enzyme, serum minerals,

hematology, milk yield and composition and milk urea nitrogen.

Dry matter intake

There were no significant differences observed between the response to the diet with or

without steep liquor on final gain, feed intake or feed efficiency (Trenkle & Ribeiro, 2002).

Feeding steep improved feed efficiency 6%, but the difference was not statistically significant.

Steers fed steep did gain faster during the period from 28 to 68 days and during the final 41 days

of the experiment. Feed was utilized less efficiently with time on feed; however steers fed steep

liquor maintained their feed efficiency during the final period.

When added to the diet of post-weaning experimental lambs at 5%, corn steep liquor

resulted in improved weight gain during 1-30 days, 31-60 days and 61-90 days as compared to

control (Mirza & Mushaq, 2006). The results were unsurprising since corn steep liquor had a

high protein, energy, B vitamins and minerals (Gill, 1997). It has previously been reported to

support better weight gains and feed efficiency in steers kept on high roughage rations. When

corn steep liquor was supplemented at higher rate i.e., 10 or 15% of diet, it did not affect the

growth or feed: gain. However, supplementation of corn steep liquor at 20% of diet significantly

depressed the growth of lambs. The response of sex of the lambs on growth, which was

inconsequential in the initial period of the trial (1-30 day) became very evident in subsequent

days of the trial (31-60 days and 61-90 days) when growth rate in male lambs was significantly

higher than that of female lambs.

Ketelaars and Tolkamp, (1996) reported that O2 consumption regulates the intake in

ruminants. Feed intake in ruminants has both positive as well as negative outcomes (benefits and

costs). Total net energy for maintenance and gain is considered as benefit and consumption of

II

total oxygen consider as costs in ruminants. The total yield of net energy per liter of oxygen

consumed is known as oxygen efficiency. Differences in intake can be interrelated with cost of

processing feed (energy utilization). Optimum oxygen efficiency is considered as a principle for

controlling other behaviors.

Slyter et al. (1971) fed purified diets in which N was supplied by either 4.7% urea or

4.9% biuret, and carbohydrates by 87% wood pulp or 74% wood pulp plus 13% starch in a 4X4

Latin Square design to growing steers. They reported that diets containing urea were consumed

more slowly than diets containing biuret. However, Oltjen et al. (1969) reported that the time

taken by steers to consume was not different when urea or biuret were added in the diet, but as

the trial progressed it required increasingly more time for steers to eat the urea diet. The steers

consumed similar amounts of both diets when they were offered ad-libitum, but steers fed diets

containing biuret consumed 15% more feed than those fed diets containing urea. Hatfield et al.

(1959) reported increased feed consumption by lambs when fed diets containing biuret when

compared to those fed diets containing urea. This increased feed consumption by ruminants can

be interpreted that biuret is more palatable than urea. Cameron et al. (1991) reported that DMI

was not affected by supplementing urea in the diet. The studies (Erfle et al., 1983; Wohlt and

Clark, 1978) indicated that DMI of lactating dairy cows was not affected by feeding less than 1%

of the total DM as urea.

Knox and Steel (1999) reported that the sheep offered the urea diet ate significantly more

chaff than those offered the non-urea diet. Initially sheep supplemented with urea consumed

about 9% more chaff than those on the basal diet and this difference increased to 24% by the end

of experimentation. On an average, urea increased chaff intake by more than 16% when chaff

consumption was expressed per unit metabolic body weight. There was a significant time x diet

interaction indicating that the change in feed intake over time was not similar in all treatment

groups. This was consistent with other studies (Broderick et al., 1993), which have established

that supplementation of low quality fibrous feeds with NPN increased voluntary intake (Hogan,

1996) and digestibility of the feed (Leng et al., 1993). These results agree with data from

previous studies showing that increasing concentrate up to about 60% of dietary DM increases

energy intake but diets containing more than 60% concentrate generally depress DMI (Sutton et

al., 1987) especially in cows past the peak milk production. Intake of amino acids was not

altered when cows were fed diets supplemented with urea. Except for arginine, threonine,

III

aspartic acid, glycine, and proline, intake of all amino acids measured was depressed when the

starch content of the diet was increased because the additional starch reduced DMI.

The effect of urea on intake depends on the methodology of urea feeding and animals

adaptability to utilize urea as N source. Many workers reported that more than 1% urea in diets

could negatively affect the DMI that may have resulted either due to high concentration of NH3

in the rumen and blood or the poor taste and palatability of urea. However, feeding urea treated

roughages improved feed intake in ruminants.

Carbohydrate fractions contribute to approximately 70% of DM in the diets for lactating

dairy cows (Oba, 2011). These carbohydrates vary in digestion rate and fermentation end

products in the rumen which ultimately affect nutrient utilization by animals. Fiber ferments at a

slower pace in the rumen and often limits voluntary feed intake by physical fill (Allen, 1996,).

Starch ferments faster than fiber and can decrease rumen pH, resulting in more propionate

production in the rumen (Owens and Goetsch, 1988,). Although high starch diets increase the

energy density, the excess propionate production may cause hypophagia (Allen, 1997) and the

low rumen pH often causes milk fat depression (Kalscheur et al., 1997). Therefore, it is

important to understand the unique characteristics of each carbohydrate fraction to optimize milk

production of dairy cows.

Type of sugars also affects the volatile fatty acid profile in rumen fluid. The molar

proportion of butyrate in vitro was increased with the addition of glucose, fructose, or galactose,

but not with the addition of xylose or arabinose (Sutton, 1968). In sheep fed grass silage, feeding

xylose and fructose increased the molar proportion of propionate in rumen fluid, while feeding

sucrose and lactose increased the molar proportion of butyrate (Chamberlain et al., 1993).

Feeding lactose in place of ground corn increased butyrate, but decreased propionate

concentration in the rumen fluid of steers (Schingoethe et al., 1980) or lactating dairy cows

(DeFrain et al., 2004). Similarly, feeding milk in place of concentrate mix increased butyrate, but

decreased propionate concentration in rumen fluid (Doreau et al., 1987). Heldt et al. (1999)

noted that feeding glucose, fructose, or sucrose in place of starch increased valerate

concentration in the rumen. However, Broderick et al. (2008) showed that feeding sucrose in

place of starch did not increase valerate concentration linearly but quadratically, peaking at 2.5%

of sucrose addition on a DM basis, and others reported that it was not affected by feeding sucrose

in vivo (Kellogg and Owen 1969a; Kellogg 1969) or in vitro (Vallimont et al., 2004). Contrarily,

IV

valerate concentration was consistently increased by feeding lactose (Bragg et al., 1986; Doreau

et al., 1987; DeFrain et al., 2004).

Some studies reported that molar proportion of butyrate in rumen fluid was not affected

by feeding sugars. It can be noted that butyrate production in the rumen is not same as butyrate

concentration. The concentration is a function of production, absorption, and passage of butyrate.

Because absorption of butyrate is faster than that of acetate or propionate (Leek, 1993), butyrate

concentration in rumen fluid, either as molar % or mM, likely underestimates the actual butyrate

production. Penner et al., (2009) and Penner and Oba (2009) reported that feeding sucrose in

place of cracked corn tended to increase rumen pH without affecting butyrate concentration in

rumen fluid. But the possibility of greater butyrate production for sucrose treatment cannot be

excluded. Effects of feeding sugar on actual fermentation acid production should be evaluated to

determine if butyrate production in the rumen is affected by feeding sugars.

Nonprotein nitrogen (NPN) can be used as a whole (Hannah et al., 1991) or a part of the

supplemental protein to meet the ruminant requirement (Russell et al., 1992) and one of the most

effective methods to enhance ruminal microbial protein supplies to the host is an efficient

utilization of NPN substances. This makes the ruminant animal production cost-effective through

minimizing its RUP needs (Baumann et al., 2004). Excessive ammonia absorbed from the rumen

increases the synthesis of urea in the liver and increases the urinary nitrogen (N) excretion.

Higher blood urea and ruminal ammonia concentrations are considered responsible for decreased

feed intake (Fenderson and Bergen, 1974).

Due to the rapid fermentation of sugars relative to the other carbohydrate fractions,

rumen pH is expected to be lower for diets containing sugars. However, rumen pH is not affected

when dietary starch sources are partly replaced by sucrose (Sutoh et al.,1996; McCormick et

al., 2001; Broderick et al., 2008) or lactose (Schingoethe et al., 1980; DeFrain et al., 2004).

Furthermore, some studies report that rumen pH increases (Chamberlain et al., 1993; Heldt et

al., 1999) or tend to increase (Penner et al., 2009; Penner and Oba, 2009) with the partial

replacement of dietary starch sources with sugar. Kellogg (1969) showed that feeding sucrose in

place of ground milo decreased rumen pH. This is one of few in vivo studies that reported lower

rumen pH for a diet containing sugar in place of dietary starch sources. But their finding might

be attributed to the extremely low dietary forage allocation. Kellog (1969) fed a diet containing

only 10% forage, while experimental diets used in the other studies mentioned above contained

V

at least 30% forages on a DM basis. Collectively, there is little evidence in the literature to

support the concept that increasing dietary sugar concentration decreases rumen pH, suggesting

that the effects of digestion rate on rumen fermentation cannot be compared among different

carbohydrates (Hall, 2004).

It is not known why feeding sugar potentially increases rumen pH despite its rapid

fermentation in the rumen. However, there are several theories to explain high rumen pH for

animals fed diets containing sugar in place of starch. One possible explanation is that sugar

provides less carbon compared with starch for fermentation acid production per unit of mass

(Hall and Herejk, 2001). In addition, if greater dietary sugar supply increases the rate of passage

(Sutoh et al., 1996) or production of microbial mass (Ribeiro et al., 2005), less organic matter

would be available for fermentation acid production (Allen, 1997). Microbial glycogen synthesis

from sugars is another possible explanation. Microbes can convert sucrose to glycogen as short-

term energy storage (Hall and Weimer, 2007). This temporarily reduces fermentation acid

production in the rumen, possibly contributing to higher rumen pH. Masson and Oxford (1951)

reported that glucose, fructose, and sucrose were utilized for glycogen synthesis by holotrich

ciliates. Other sugars such as galactose, mannose, xylose, arabinose, lactose, cellobiose, and

maltose were not extensively utilized for glycogen synthesis (Oxford, 1951). Furthermore,

greater butyrate production in the rumen from feeding sugar (Vallimont et al., 2004; Ribeiro et

al., 2005) would decrease proton production per unit of ruminally degraded OM compared with

acetate or propionate production as 1 mole of hexose ferments to 1 mole of butyrate, or 2 moles

of propionate or acetate (Owens and Goetsch 1988). In addition, as discussed above, many

studies showed that feeding sugars can increase the concentration of valerate in the rumen, which

further contributes to less proton production per unit of OM fermented in the rumen.

Supplementation with rice bran caused a slight, but not significant reduction in straw

intakes representing a substitution rate of 27% straw intake of animals receiving lick block was

the same as for animals not receiving lick block. In contrast with straw intake total DMI

increased from 85.8 to 97.3% because of supplementation with rice bran. However, animals fed

treated straw consumed significantly more total DM than those receiving untreated straw and

rice bran. The DMI by animals receiving lick block was not significantly higher than those not

receiving lick block. The results were similar for total intake of OM. Pearson and Smith (1993)

found no increased in hay intake because of urea/molasses supplementation although live weight

VI

gain increased. Cameron et al. (1991) reported that intakes of DM, OM, ADF and NDF were not

affected by supplementing urea in the diet where urea supplied about 12.5% of the total N in the

diets and these diets contained about two percentage units more CP than those diets not

supplemented with urea. These data supported the previous reports (Erfle et al. 1983; Wohlt and

Clark, 1978) indicating that DMI of lactating dairy cows was not affected by feeding less than

1.0% urea of the total dietary DM.

Nutrient digestibility

The higher degradability rate of urea treated corncobs ensiled with 9% corn steep liquor

than that ensiled without corn steep liquor may be a reason for its increased fiber digestibility

(Nisa et al., 2004). This indicated that some delignification occurred during ensiling of straw that

consequently improved digestibility (Sarwar et al., 2003). They further reported that negative

relationship between degree of lignification and cell wall digestion in forage was well

recognized. Sarwar et al. (1994) concluded that improved digestibility of ammonia treated

corncobs might be the result of ammonolysis of galacturonic acid esters attached to xylan chains

of hemicellulose. Ammonia may spongify ester bonds between lignin and hemicellulose and

saturates H-bonds linking the matrix polysaccharides.

A significant increase in digestibility of dry matter (DM), crude protein (CP), neutral

detergent fiber (NDF) and acid detergent fiber (ADF) with urea treated wheat straw ensiled with

corn steep liquor has been reported by Nisa et al. (2006). These differences have been attributed

to higher rates of degradability of urea treated wheat straw ensiled with 9% corn steep liquor

than that ensiled without corn steep liquor (Nisa et al., 2004). Increased digestibility of urea

treated wheat straw ensiled with corn steep liqur probably involved the breakage of alkali-labile

bonds in the wheat straw fiber (Ali et al., 1993). Ammoniation in combination with corn steep

liquor treatment might have sponified esters bonds between lignin and hemicellulose and

saturates H-bonds linking the matrix polysaccharides and thus improve the degradability and

digestibility of DM and NDF. Further, the decreasing percentage of NDF might have caused the

reduction in ruminal pH that might have slowed down the activity of cellulolytic microbes

(Sarwar et al., 1992). Increased levels of ruminal escaped protein might have improved apparent

CP digestibility.

Rumen fill effect in ruminants is due to the slow flow rate of digesta through GIT which

limits the voluntary dry matter intake especially in case of forage intake (Allen, 1996). Flow rate

VII

of digesta is depending upon the volume and weight of digesta that is main reason of rumen fill.

A main organ of distention is the reticulorumen which is considered as a fermentation chamber

(Baile and Forbes, 1974) but abomasum may also limit intake in ruminants (Grovum, 1979).

Cranial sac responses to rumen fill through tension receptors which is located on reticulum

(Leek, 1986). Forbes (1995) proves that the quantity of undigested residues in rumen and their

post-ruminal flow also limit the feed intake in ruminants. Important constituent of feed and

forage like neutral detergent fiber ferments and passes slowly through the reticulorumen and has

a larger filling effect than other nutrients of diets (Van Soest, 1965, Martens, 1987). Many other

partially filling effects including, chewing rate, indigestible NDF fraction, particle size and

contractions of reticulum also limit the intake (Jarrige et al., 1986; Allen, 1996).

Williams et al. (1984) and Wanapat et al. (1985) reported that urea treatment of straws

significantly increase the nutritive value and digestibility. Similarly, Mahmood (1988) found that

dry matter digestibility was the highest with 4% urea. Johnson and McClure (1964) and McLaren

et al. (1959) have reported marked depression in cellulose digestibility when biuret fed lambs

were compared with urea fed lambs. However, in other studies where a 3-week or longer feeding

period has been allowed, little difference in cellulose digestion has been found between urea and

biuret fed ruminants (Campbell et al., 1963). They explained that the ruminal NH3 concentration

in steers fed biuret might have been too low to promote optimal utilization. The apparent

digestibility of different NPN sources was not significantly different. Other workers (Anderson

et al., 1959; Johnson and McClure, 1964) have reported that apparent digestibility of urea was

significantly greater than that for biuret while similar digestibility have also been reported

(McLaren et al., 1959; Campbell et al., 1963). The urinary N losses were greater (p>0.05) for

biuret and urea phosphate. Although the digestibility of these NPN sources was the highest, but

the utilization of degraded N was not as good as with other NPN sources. Hatfield et al. (1959)

reported that on the lower level of feed intake, the apparent digestion coefficient for N was

significantly lower for biuret ration than for biuret plus urea and urea rations. On the higher level

of feed intake, the average apparent digestion coefficient for N was the highest for the urea ration

and the lowest for the biuret ration, with the urea-biuret ration having intermediate value. These

averages were significantly different from each other.

Cameron et al. (1991) reported that ruminal digestion and passage to the duodenum of

DM, OM, starch, ADF and NDF were not affected by supplementing urea in the diet. The daily

VIII

quantities (kg/ d) of OM, starch, ADF and NDF digested post ruminally also were not altered by

supplementing urea in the diet but OM digested post ruminally expressed either as a percentage

of OM intake or a percentage of OM that passed to the duodenum was increased by

supplementing urea in the diet. The significantly greater percentage of OM digested post

ruminally for diets supplemented with urea compared with diets not supplemented with urea can

be explained by the concomitant increase in percentage of fibre digested post ruminally.

Digestibilities of ADF and NDF that passed to the small intestine were increased by 5.49 and 5.7

percentage units, respectively, when urea was added to the diet. Therefore, small increases in

total tract apparent digestibility coefficients were obtained for DM, OM, starch, ADF and NDF

when urea was added to the diet, but these small increases were not significant. As they observed

with lactating cows, ruminal DM digestion was not affected but post ruminal DM disappearance

was significantly improved by infusing 9.8 g/d of urea into the rumen of sheep fed high

concentrate diets (Owens et al., 1973).

Likewise, Ortigues et al. (1988) reported that ruminal digestion of DM and ADF was not

affected by supplementing urea in diets consisting of fescue hay. However, post ruminal

digestion of DM and ADF was improved when urea was supplemented to the diet, because the

quantity of DM and ADF that disappeared from the cecum and colon was increased whereas the

amounts of DM and ADF digested in the small intestine were not altered significantly.

Therefore, the improved post-ruminal digestibilities of these dietary components may not have

been of sufficient magnitude to increase total tract apparent digestibility coefficients

significantly. Cows fed diets supplemented with starch digested a larger percentage of starch in

the rumen and a smaller percentage post ruminally than cows fed diets not supplemented with

starch. In contrast, Klusmeyer et al. (1991) reported that ruminal and postruminal starch

digestion was not affected by increasing the amount of concentrate in the diet. Replacing corn

with more fermentable barley starch increased ruminal degradation of starch (McCarthy et al.,

1989). They further reported that supplementing urea in the diet increased N intake and

percentage of dietary CP degraded in the rumen.

Limiting nutrients especially protein, reduces the intake of digestible energy due to

metabolic limitation for energy processing. On the other side, with high in protein may be

metabolized for energy (Fisher, 2002). The basic theme of this theory is that ruminant have an

optimum capacity for maximum usage of different nutrients to fulfill their productive

IX

performance. In other words, the ability of healthy animals to metabolize feed varies with animal

class and condition (Illus and Jessop, 1996). In addition, animal maintains a specific level of

body fat in body. This metabolic control through leptin and insulin is called the lipostatic

feedback (Ceddia et al., 2001).

Hoover (1986) reported that when readily fermentable carbohydrates (RFC) were added

to forage diets, fiber digestion was depressed both in vivo and in vitro. As little as, 10 to 15%

added RFC can impair fiber digestion, but severe depressions were usually associated with of

30% or more of RFC or grain of DM intake. Results of some studies suggested that attachment

involved in the depression of fiber digestion associated with moderate decrease in pH (Sarwar

and Ali, 2000). Thus, low ruminal pH appeared to prevent a tight attachment of bacteria to plant

cell walls, resulting in no overt fiber digestion.

In several other reports, the concentration of NH3-N associated with maximum microbial

output or fermentation ranged from 7 to 76 mg/dL (Allen and Miller, 1976, Edwards and Bartley,

1979). The circumstances responsible for the wide range in NH3-N reported as optimum

microbial growth or fermentation have been clearly defined. They reported that changes in

rumen environment or microbial population could influence the rate at which NH3-N was taken

up by microbes, affecting microbial production at a given NH3 concentration. This concept was

supported by observations that the major pathways of NH3 assimilation by microbes were

influenced by N source (Chalupa et al., 1970) and NH3 concentrations (Allison, 1980). Another

suggestion was proposed by Allison (1980) who speculated that the NH3 concentration

monitored in the rumen fluid might be quite different from that available to micro-colonies

intimately associated with starch granules. This view is similar to many scientists who theorized

that the NH3 concentration required by the adherent, fiber digesting organisms may be greater

than the requirements of the free floating organisms in the rumen fluid. An additional factor that

may affect NH3 requirement is the competition between fibrolytic and non-fibrolytic organisms

for various forms of N containing compounds when grown under conditions of limiting available

protein. A high requirement for amino acids or peptides has been proposed for sugar utilizing

organisms, although cellulolytic organisms require primarily NH3 as N source (Baryand, 1973,

Baryand and Robinson 1962).

Proteins are superior to urea for the maintenance of fiber digestion indicating a

requirement for amino acids or peptides in addition to NH3. Amino acids improved growth on an

X

NH3 media of one of three cellulytic species studied by Baryand and Robinson (1962). In several

of the studies in which the concentrations of NH3 required for optimum microbial growth or

fermentation exceeded 6 mg/dL (Allen and Miller, 1976; Belasco, 1954; Hume et al., 1970), the

basal diet contained less than 6% CP but sufficient readily fermentable carbohydrate to support a

vigorous non-fibrolytic population. It is suggested that under conditions of high fermentable

carbohydrate and limiting available protein, NH3 concentrations required for optimum growth of

cellulytic organisms may be increased. When the natural CP was equal to or less than 6%, NH3

associated with optimum microbial growth or nutrient digestion was 21.4 mg/dL compared with

an optimum NH3 concentration of 6.2 mg/dL when the dietary protein was over 6%. In studies in

which the dietary protein was over 6%, microbial growth was optimized at a lower NH3,

supporting the proposals that attached microbes may either require more NH3 or be exposed to a

lower NH3 concentration than the free floating organisms. It is likely that the amino acid

requirement of cellulytic organisms is associated with the requirements for the fatty acids such as

isobutyric, isovalaric and 2-methyle butyric that result from the deamination of valine, leucine

and isoleucine, respectively (Allison et al., 1973). These acids along with valaric and isoacids

were required in small amounts for growth of cellulytic microbes (Baryand 1973, Dehority et al.,

1967) and addition of valaric and isoacids to cultures of rumen microbes improved cellulose

digestion (Gorosito et al., 1985). In spite of the proven requirement of cellulolytic microbes for

these metabolites, a number of studies (Cline et al., 1966; Helimsley and Moir, 1963) failed to

show improved fibre digestion when isoacids were added to a low protein diet.

A possible explanation for the inconsistent results of isoacids additions was that the

sufficient isoacids for growth of Ruminococcus albus were produced by sequential growth of

other organisms. The lysis of Bacteroides amylophilus, which grew in the NH3-containing

medium, provided the amino acids, which were subsequently deaminated by Megasphaera

elsdenii, forming the isoacids. It can be theorized that an insufficiency of isoacids may occur

when the solids retention time of rumen contents is short enough to cause decreased ruminal

degradation of both dietary and microbial protein. About 36 h were required for bacterial lysis to

increase isoacids. In comparison mean rumen retention times of 15 to 25 h have been reported in

cattle fed large amounts of forages and grains (Cline et al., 1966) under such conditions available

protein could be further reduced by feeding protein of low ruminal degradability.

XI

The importance of protein source was shown by Gorosito et al. (1985), who added

isoacids to in vitro incubations of seven different forages and found improved fiber digestion

with alfalfa hay, orchard grass, and corn silage but not with timothy hay, canary grass or

bermuda grass. They concluded that total protein was not a reliable index of isoacid adequacy. In

an in vivo study, the competition among microbes for the various available N sources may have

been responsible for the depression in DM digestibility in a diet for lactating cattle formulated

with proteins of low degradability (Erdman and Vandersall, 1983). Although in their work, no

attempt was made to associate digestibility depression with availability of isoacids or NH3, these

were shown to be responsible for depressed digestibility in the continuous culture. They reported

that diets formulated with either normal or formaldehyde treated soybean meals were supplied to

fermentations in which the solid retention time was set at 16 h. Digestion of OM and NDF was

decreased in the diet with the treated soybean meal. Separate infusions of urea and isoacids

mixture partially restored OM and NDF digestion whereas infusion of urea and isoacids

combined restored OM and NDF digestion to amounts obtained when normal soybean meal was

fed.

Nitrogen balance

Ammoniation of WS through urea treatment may improve nitrogen intake and retention

in animals. Oltjen et al. (1968) and Oltjen and Dinius (1976) reported higher nitrogen intake and

retention when WS was treated with urea. Sarwar et al. (2003) also reported increased nitrogen

intake when WS was treated with urea and molasses. Higher nitrogen intake might be related to

higher DM intake in animals receiving urea treated WS (Staples et al., 1981). Sarwar et al.

(2006a) observed nitrogen intake increased with increasing level (0, 15, 25 and 35%) of treated

WS in the diet of growing calves, when WS was ensiled with urea (4%), molasses (4%) and

cattle manure (30%). They further stated that higher nitrogen intake in animals receiving FWS

based diets was due to better ruminal environment leading to higher DM degradation and rate of

passage which ultimately reflected increased nutrients intake. Smith and Lindahl (1978) reported

higher nitrogen intake and excretion in animals fed diets containing liquid extracted from animal

excreta, however nitrogen retention remained unaltered. Hassan (2004) reported unaltered

nitrogen intake in animals fed diets containing WS treated with urea (4%), molasses (4%) and

cattle manure (30%).

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Cornman et al. (1981) reported an increasing trend in nitrogen intake and excretion with

increasing level of cattle manure in lambs’ diets. However, Harpaster et al. (1978) reported

decreased nitrogen intake when corn crop (40%) was ensiled with animal waste (60%).

However, nitrogen retention was higher in animals fed corn crop treated with cattle manure.

Higher nitrogen retention might be related to lower fecal and urinary nitrogen. Islam et al. (2001)

reported increased nitrogen intake and urinary nitrogen when Italian grass was treated with urea.

However, N retention was lower in animals fed urea treated Italian grass. Whereas, Sarwar et al.

(2006b) reported increased N intake and retention when urea treated WS was fed to bovine

somatotropin treated buffaloes. They also found that nitrogen intake and retention can further be

increased by the ensilation of urea treated WS with enzose. Khatak et al. (2009) also reported

higher nitrogen retention in animals fed diets containing molasses treated WS. Hatch and Beeson

(1972) also reported higher nitrogen retention in steers. However, Brown et al. (1964) reported

that molasses had no effect on N intake and its retention in lactating cows.

Hatfield et al. (1959) reported that the N balance was significantly higher for the biuret

ration than for urea ration at restricted level of feed intake. However, at ad lib feed intake, the N

balances for the biuret ration was significantly lower than the urea-biuret ration but it was only

slightly lower for the urea ration. The positive N balances in the metabolic studies provided

evidence of the utilization of N in the ration. It was highly improbable that there was sufficient

non-biuret N available for metabolism and the positive N metabolism and the positive N balance

in the biuret rations. They explained that the differences in the N intake and or the N utilization

might have affected the N balances with lambs. However, it should be noted that the percent of

apparently digested N that was retained (balance) was higher in lambs on the biuret ration than in

lambs on the urea ration at both levels of feed intake.

Growth performance

Steers fed steep gained faster during the period from 28 to 68 days and during the final 41

days of the experiment conducted by Trenkle (2002). Overall gains of steers fed both diets

declined with time on feed. Feed intake when averaged by period increased up to 104 days and

then declined for the control steers and continued to increase for the steers fed corn steep liquor.

Poor growth performance and poor efficiency of feed utilization in calves fed corn steep liquor

has been observed by Gupta et al. (1990). Wagner et al. (1983) also reported weight losses in

cows fed corn steep liquor. It was reported that supplementation of corn steep liquor resulted in

XIII

higher rumen ammonia 1 h and 4 h post-feeding with a drop in rumen pH, greater soluble

carbohydrate concentration and lower ruminal acetate and higher butyrate. It is well documented

that when rumen pH is 7.2 or higher, rumen NH3 is rapidly converted to free ammonia and is

absorbed across the rumen walls. In contrast, an acidic pH combined with greater availability of

NH3 and soluble carbohydrates promotes greater microbial protein synthesis in the rumen.

Besides, excess sulphur present in the corn steep liquor (0.70% of the dry matter) could also

impair animal growth performance. The problem could arise when the sulphur is above 0.40%,

estimated to be the maximum tolerable concentration (NRC, 2001).

Oltjen et al. (1969) reported that urea appeared to be slightly superior in terms of animal

performance, under ad libitum feeding but biuret was clearly superior under twice daily feeding.

The apparent discrepancy between the metabolic and growth trial results when the steers were

fed twice daily may be explained by the fact that the steer’s in the metabolic trial were restricted

to consume an amount of feed equal to 2% of each steers’ body weight. While, steers in the

growth study consumed 2.2 and 2.5% of their body weight of the urea and biuret diets,

respectively. This increased consumption of urea in a shorter period might have resulted in high

ruminal NH3 concentrations and poor utilization of the urea N. The second reason to explain

these results could be the low dissociation of biuret molecule to NH3 per h at ruminal level as

compared to urea. This low rate of biuret dissociation per h may be the factor that could improve

the synchronization of nutrients at ruminal level for enhanced microbial growth and ultimately

productivity by the animal. Hatfield et al. (1959) reported satisfactory growth rates of lamb on

both urea and the biuret supplemented rations. The average gains by the sheep fed on the biuret

rations were slightly less than average gains by sheep fed on the urea rations for the first three

weight periods. However, the average gains of the sheep receiving the urea or biuret

supplemented rations were good and almost identical at the end of 54 d. They explained that

small amounts of urea in the saliva of animals probably promoted and maintained a sufficiently

large part of the normal rumen flora to allow quick adaptation for utilizing larger concentrations

of urea. However, a longer period may be required for the normal rumen flora in animals that

had not been previously fed biuret N to adjust to biuret containing feed than to adjust to higher

concentrations of urea.

The results of different studies concluded that urea feeding improved the animal

performance in terms of milk production and growth, importantly under those conditions where

XIV

animals were fed on poor quality roughages. Beneficial effects of urea for enhanced animal

productivity could be achieved by adopting the methodology for its slow utilization and

maximum synchronization with available energy at ruminal level.

Meat characteristics

Being the sources of nonprotein nitrogen and energy, the agro industrial byproducts also

play significant role in the dressing percentages and other meat quality parameters. All these

parameter and impact of agro industrial byproducts on these parameters have been described

below.

Dressing percentage

Forage finishing of beef has produced mixed results on carcass characteristics and

palatability attributes. Some researchers discouraged forage finishing because of deleterious

effects on carcass and beef quality, but others (Crouse et al., 1978) found no differences in

palatability attributes between forage and grain finished beef. Berthiaume et al. (2006) noted that

many studies that compared forage vs grain finishing have been confounded regarding backfat

finish and days on feed between forage- and grain-fed beef. In those studies, forage-fed cattle

often had minimal amounts of finish or were slaughtered at ages older than those of grain-fed

cattle. Our past work compared forage vs grain finishing at similar backfat finishes (Berthiaume

et al., 2006).

Armstrong (1989) had shown that microbial CP synthesis was improved to a greater

extent when a source of ruminally degradable protein was supplied at the same time as sugars

rather than when they were fed separately. Most experiments conducted on sugar and protein

supplementation had been conducted with restricted-fed animals (Huhtanen, 1991). However,

this would suggest that results from trials conducted at restricted feeding levels cannot

necessarily be applied to production situations in which animals are fed at or near ad libitum

intake.

Fish meal supplementation increases the average daily gain (ADG) of silage-fed animals

(Petit, 2002; Petit and Castonguay, 1994). Moreover, soybean meal increases microbial CP

synthesis in silage-fed animals. This could partly explain why ADG of silage-fed animals is

similar when supplemented with fish meal or soybean meal (Veira et al., 1985). However, fish

meal and soybean meal are more expensive than canola meal, which would be a good CP source.

Combining canola meal with molasses might increase microbial CP synthesis in the rumen by

XV

supplying a source of readily available energy to the microbes and decrease the need to

supplement with protein.

High carcass yield production and distribution of carcass tissue in small ruminants is well

established (Johnson et al., 1995). Sheep has 6% higher dressing percentage than goat (Riley et

al., 1989; Sen et al., 2004). Higher DP is due to higher slaughter weight (Lupton et al., 2007),

lower gastro intesetinal tract (GIT) percentage in sheep (Sen et al., 2004) and relative fatness of

the carcass (Chestnutt, 1994; Murphy et al., 1994). Dressing percentage (DP) has increasing

trend with increase of CP contents (Atti et al., 2004). Higher dressing yield is due to their higher

pre slaughter weight or relative fatness of carcass.

Carcass composition

Plane of nutrition, composition of diet (Todaro et al., 2006) and slaughter weight (Saleh,

1972) affects the chemical composition of carcass. Increasing energy levels of diet also improve

the carcass composition. Animals have maximum moisture and more protein in longissimus

dorsi muscle when fed 13% protein diets as compare of low protein (Atti et al., 2004). Dry

matter, crude protein, ether extract and ash percentage of meat are not significantly different for

different ME levels but dry matter and crude protein percentage decreases with increase of

energy level (Shadnoush et al., 2004). The CP percentage of meat decreases with increase of

slaughter weight (Kemp et al., 1980; Shadnoush et al., 2004). In all species a bone are early

developed and does not depend on feeding regimens but muscle especially fat depots depend on

nutrient utilization (Atti et al. 2004). Bone, muscle and adipose tissue weight does not depend on

the increase of CP level in diet and have maximum protein and low fat at 13% CP level of diet

(Atti et al. 2004) due to efficient use of nitrogen at this level.

Carcass mineral contents

Concentration of minerals in bone tissue especially Ca and P is influence by feeding.

According to Bellof et al (2006) the major element concentrations of all tissues (bone tissues, fat

tissues and muscles tissues) of carcass are significantly influenced by the body weight. An

influence of gender could be noticed for all elements except Ca in the muscle and fat tissues. In

bone tissues, however, only the elements Na and K were influenced by gender. The feeding

intensity had no significant effect on concentration of major elements in the tissues. In calves’

muscle tissue combined from all parts (body weight 18-45 kg, both sexes) the following

concentrations of major elements were analyzed: 323mg K, 185 mg P, 61.7 mg Na, 20.2 mg Mg

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and 10.6 mg Ca (per 100g meat, wet weight basis). The major element contents of bone ash are

on average 37.1% Ca, 18.0% P, 1.43% Na, 0.80% Mg, and 0.52% K. The mineral contents of

muscle tissue of fattening lambs are influenced by genotype (Hoffman et al., 2003)

The Ca:P ratio of 2.1:1 in bone ash corresponds to Ca:P ratio in hydroxyapatite, the most

important compound in bone tissues. According to the ARG (1980) growing calves have

between 110 and 200 g Ca and 50 and 100 g P per kg bone tissue (wet weight basis) but 18 -55

kg calf has 97.9g Ca and 46.6 g P in bone tissues (Bellof et al., 2006). Faster growing lambs (270

g daily weight gain) showed significantly lower rates of mineralization in the bone than slower

growing animals (140 g daily weight gains) of the same age. The Ca:P ratio (femur) in the slower

growing animals was with 2.31:1 significantly wider than in faster growing animals (2.20:1).

Bellof et al. (2006) founded that slower growing animals (201 g daily weight gain) showed 96.7

g Ca and 46.2 g P per kg bone (wet weight basis) while the faster growing calves (244 g daily

weight gain) retained only 94.7 g Ca and 45.7 g P per kg bone. The magnesium (Mg),

Sodium(Na) and Potassium(K) content in the bone tissue of sheep amounted to 2.0 g/kg, 3.4 g/kg

and 1.0 g/kg respectively (Bellof et al., 2006) and according to ARC (1980) 2.0 g/kg, 4 g/kg

and <0.05 g/kg in lamb respectively. The bone tissue of carcass contained 99.6% of the whole

calcium content (45 kg final body weight). For phosphorus 90.0%, for magnesium 78.4%, for

sodium 63.8% and for potassium 12.1% (Bellof et al., 2006). The ARC (1980) gives comparable

data related to empty body weight: calcium 99%, phosphorus 75-80% and magnesium 70%

Blood metabolites and hormones

Agro industry byproducts as a livestock feed play an important role in abridging the gap

between nutrient demand and availability. Normal values of different blood metabolites are

necessary for normal life of ruminants and they tell us that how different feeding regimens i.e.

non-protein nitrogen and energy, affect these blood metabolites. The role of agro industrial

byproducts has been well documented in maintaining the flow of blood metabolites. Circulating

blood in body has many blood constituents and it plays an important role in maintaining the

survivability. The following paragraphs explain the role of agro industrial byproducts in

maintaining their normal levels.

Nutritional status of ruminants can be judged metabolically with the help of circulating

thyroid hormones (Todini et al., 2007). Thyroid gland gets stimulated with the availability of

large amount of energy. Intake of energy in higher amount has a direct positive impact on total

XVII

plasma T4 concentrations compared with that of lower energy. In ruminants, the concentration of

plasma thyroid hormones i.e. T3 (triiodothyronine) and T4 (tetraiodothyronine or thyroxine) is

positively correlated with feed intake. Therefore, thyroid hormones in the circulation can indicate

a relevant metabolic index of the animal’s nutritional status. T3 and T4, both act on different

target tissues and stimulate oxygen utilization and heat production in every cell of the body. As a

result, they increase the basal metabolic rate and make more glucose available to cells, stimulate

protein synthesis, increase lipid metabolism and stimulate cardiac and neural functions (Todini et

al, 2007). In this context, Souza et al., (2002) reviewed the role of these thyroid homones. They

concluded that these hormones control the body’s metabolic activity by regulating oxidative

cellular processes and RNA and cytoplasmic protein synthesis. Thyroid hormones appear to have

a pivotal role in the regulation of seasonal reproduction in sheep. Season affects the thyroid

activity and the absence of thyroid hormones hampers the normal reproductive endocrine

function in rams. Todini et al., (2007) reviewed that T3 is directly responsible for the stimulation

of feed intake at the hypothalamic level, independent of alterations in energy expenses, while on

the other hand, type of diet may also affect the levels of plasma thyroid hormones. Blood thyroid

hormones are thought to be the good indicators of nutritional status of animals.

The pool size of plasma glucose remains unchanged but plasma glucose turnover rate

tends to increase by increasing the energy levels. It is pertinent to note that gluconeogenesis in

ruminant animals tends to increase during feeding and decrease during starvation; therefore,

precursor availability is an important factor in regulating gluconeogenesis (Sano et al., 2006).

According to Davies et al, (2007) plasma glucose, creatinine, albumin, Na, K and C remain

unaffected by any change in the diet.

Wilson et al. (1975) stated that an increase in the dietary urea level resulted in the

consequent increase in the ruminal NH3 and ultimately venous urea. Virtanen (1966) reported

that when samples were taken at 6 to 8 h post urea feeding, an increase in the levels of venous

NH3 in jugular blood was not seen. However, pouring urea into the rumen tended to increase

venous NH3 but the difference was not significant. In the liver, NH3 is converted into urea

because this compound is highly soluble and being electrically neutral, does not affect the pH

when it gets accumulated, as does the urea. However, NH3 has a tendency to pass beyond the

liver and extra systemic circulation, which depicts an increased N (BUN) in buffalo bulls when

fed diets containing urea and urea plus molasses. The BUN in all bulls increased at 6 h post

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feeding and this was probably due to higher absorption of NH3 through the walls of rumen. The

values of BUN for all the rations were almost similar at zero and increased at 6 h post feeding in

urea-based diets. It was assumed that the blood urea formed from NH3 has been absorbed

through rumen wall and was almost continuously recycled but NH3 was constantly absorbed into

the blood from rumen until high blood NH3-N resulted in a higher BUN formation. These results

were summarized by the findings of Kowalczyk et al. (1976).

Slyter et al. (1971) reported a non-significant difference in the concentration of blood

urea in steers fed urea or biuret 16 h post feeding. The difference in blood urea in steers fed diets

containing N sources has been shown to occur at earlier time intervals after feeding (Oltjen et al.,

1969). Broderick et al. (1993) reported a lower blood urea level when true protein was offered

than those when the urea was fed. These findings had probably been due to an increase in the

rate of ruminal NH3 formation when urea was offered. In other studies, Broderick et al., (1986

and 1993) reported the same urea concentrations in blood and milk. Concentrations of urea in

blood elucidates that ruminally degraded protein may have been limiting in diets containing true

protein. Those researchers had further reported that the non-essential amino acids (Proline and

Glycine) were generally in higher concentrations when true protein sources were supplemented

in the diets of lactating cows. The concentration of essential amino acids in the blood plasma

remained unchanged for both true protein and urea supplemental diets. The delayed response of

essential amino acids in blood plasma demonstrated that protein status was not improved

significantly when dietary true proteins were fed. The reduced ruminal protein degradation might

have limited microbial protein synthesis.

Blood metabolites

Blood urea nitrogen (BUN) is a measure to assess protein status of the animal. Blood urea

nitrogen and protein intake have a positive relationship indicating that BUN could be quantified

with protein intake (Preston et al., 1965; Rusche et al., 1993). Higher BUN in lambs fed

concentrate diet might be the result of incapacity of ruminal microflora to retain maximum

ammonia (Butler, 1998). Serum creatinine is a marker of kidney function and glomarular

filtration rate (Swaminanthan et al., 2000). Ponnampalam et al. (2005) reported non-significant

difference in plasma urea and glucose in crossbred lambs at d 1 of the trial due to CM, SBM and

FM supplemented to control diet (lucerne hay: oat hay; 30:70). However, at d 30 and 53 of

sampling revealed significant increase in plasma glucose and urea N concentration except for a

XIX

decrease in urea N concentration in basal treatment. Lupin supplementation as protein source on

weekly basis increased levels of urea in plasma whereas variations were found in blood glucose

levels (Master et al., 2002). Plasma glucose and urea N were unaffected in lambs fed concentrate

diets (Carro et al., 2006). Increase in glucose concentration may be due to more by-pass protein

and increased availability of glucogenic amino acids for glucose synthesis (Sano et al., 2007).

Rusche et al. (1993) observed that feeding CP source with high escape protein decreased

plasma glucose and urea N concentration. Whereas, supplementation of lucerne chaff with CSM

resulted in an increase in glucose and urea concentration in lambs indicating better energy and

protein status (Sainz et al., 1994). Paterson et al. (1983) observed lower BUN in lambs offered

escape protein supplements compared with SBM supplement (11.07 versus 16.44 mg/100ml).

However, Davies et al. (2007) noticed no difference in plasma glucose, urea N and plasma

minerals in response to various protein sources. In conclusion, feeding protein with high rumen

un-degradable value resulted in increased concentration of blood glucose due to more glucogenic

amino acids available for gluconeogenesis.

Serum minerals

Serum sodium (Na), chloride (Cl) and potassium (K) ion concentrations differed in

response to protein supplementation in sheep (Oboh and Olumese, 2008). Likewise, concentrate

diets resulted in higher serum phosphorus (P) levels in goats (Hayashida et al., 2004). However,

serum Na and K concentrations were not affected by diet composition 10 (Davies et al., 2007).

Similarly, serum Ca, P and Mg levels remained unchanged in sheep fed diets supplemented with

protein as compared to the control (Cole, 1992).

Hematology

Adequate quantity of dietary protein is essential for normal hemoglobin (Hb) formation

in animals that carries oxygen to tissue from lungs. Low protein intake may alter the absorption,

retention / or utilization of substances which is essential for normal hematopoiesis (Orten and

Orten, 1947). The protein content of diet may affect the iron absorption in intestine (El-Hawary

et al., 2008). Low protein fed animals have subnormal Hb and normal erythrocytes in blood as

compared to adequate protein fed animals (Orten and Orten, 1947; Conrad et al., 1967).

Protein increases the absorption of radioactive Fe from the gut (Higginson et al., 1965).

This promoting action on iron absorption may be partly the result of the action of free amino

acids released from dietary proteins. Supplementation with valine and histidine increased

XX

intestinal iron absorption in anaemic subjects (El-Hawary et al., 2008). Optimum Hb synthesis

increases the availability of oxygen for anabolic activity leading to increased production of

energy for muscle mass accretion. Hemoglobin, hematocrit (PCV) and mean corpuscular

hemoglobin concentration (MCHbC) are very responsive to protein deficiency / low protein

inatke (Edozien and Switzer, 1977). Therefore, a sufficient quantity of dietary protein with

efficient amino acid profile is a must for maintaing optimum concentration of blood constituents.

The MCHbC increased with increasing protein concentration in diets (Edozien and Switzer,

1977).

The protein-energy deficiency increases the plasma volume which alters the Hb

concentration and change in intracellular reduction of MCHbC (Edozien and Switzer, 1977).

Hematocrit was nonsignificant but Hb was significant among varying levels of CSM (0, 15 and

30%) in growing lambs (Nikokyris et al., 1999). The total red blood cells (TRBC), PCV, mean

corpuscular volume (MCV), Hb, white blood cells (WBC), plataletes, were nonsignificant

whereas segmented granulocytes and lymphocytes were significantly different in animals fed soy

or non-soy diets (Pastuszewska et al., 2007). Tripathi et al., (2007) observed that WBC,

lymphocytes, neutrophils, and, Hb, MCV were nonsignifcnat whereas eosinophils , red blood

cells (RBC), PCV, Hb and MCHbC were significantly different in animals fed graded levels of

feed grade damaged wheat as substitute of maize. In another study, Hb and PCV were not

influenced by diets (Matras et al., 1991). Gill et al (1987) also observed no effect of different

feedig regimens on Hb, erythrocytes and PCV.

Nikokyris et al. (1999) observed higher values for PCV (33-39.1%), Hb (94.4-120.7 g/l)

and MCHbC (27.8-30.9 g/dl) at the beginning of the trial as compared to the middle and end of

the 62 days of trial in growing fattening lambs fed diets containing 0, 15 and 30% cotton seed

cake. However, Nelson and Watkins (1967) reported that blood Hb and PCV were unaffected by

interval of CSM supplementation as protein source indicating adequate homeostatic mechanism

to prevent any change in blood constituents.

Claypool et al. (1985) observed non-significant differences in the PCV (24.4, 22.9 and

24.9%) in calves fed diets supplemented with CM, CSM and SBM, respectively. Nikokyris et al.

(1999) reported that most of the blood components were affected by varying levels of dietary

free gossypol on whole cottonseeds in the growing fattening lambs. Hematocrit values were

higher at the start of the trial but, overall, remained unchanged.

XXI

Blood Biochemistry

The serum urea concentration is closely associated with the break down and deamination

of the protein in the rumen and the rate of utilisation of NH3 for bacterial protein synthesis. An

increase in the serum urea level may reflect an accelerated rate of protein catabolism rather than

a decrease in urinary excretion (Kaneko, 1980). The serum urea level also increases in renal

tubular necrosis and decreases in hepatic insufficiency and low protein intake (Kaysen et al.,

1985).

An increase in the serum creatinine levels is generally seen in degenerative muscle

diseases (Prassee, 1986). The quantity of creatinine formed each day depends upon the creatine

content of the body, which in turn depends upon the dietary intake, inhibiting the endogenous

synthesis rate and the muscle mass (Walker, 1961). Elevated creatinine levels in the

serum/plasma are also associated with various renal diseases. Creatinine is formed during the

metabolism of creatine in the muscle and its increased concentrations in the serum are the

indicator of a decreased glomerular filtration rate.

Transamination of amino acids is a synthetic function of hepatic cells and the enzyme

AST catalyses this reaction. Therefore elevation of serum AST is a highly sensitive indicator of

hepatic insufficiency (Hill and Kelly, 1974). The AST/ALT ratio is considered (ASPA, 1999) to

be of greater use, with respect to concentrations of each of the two enzymes, for evaluating

whether there are conditions of suffering or liver damage (Bovera et al., 2002). Among various

tissues and organs, higher ALP activities occur in the kidneys and intestines, while there are

moderate in the liver, lungs, bone, placenta and leukocytes (Cornelius, 1980). However, the use

of ALP as a diagnostic tool for detecting tissue damage is limited, especially in young growing

animals, where bone can be a very significant source of ALP (Evans, 1988). ALP plays an

important role in the regulation of cell division and growth (Swarup, 1981) and its activities

reach higher levels in the serum of growing animals. The result revealed that although the serum

alkaline phosphatase values were within the normal range, there was a gradual increasing trend

in the mean values of serum alkaline phosphatase (ALP), which could be attributed to the effect

of their normal physiological growth. On the contrary to this, Ahuja et al., 1977 did not find any

change in serum ALP activity in buffalo bulls fed on urea for a prolonged period. Serum GOT

and GPT are both cytoplasmic and mitochondrial enzymes and are distributed in all body tissues.

They are released by even mild degenerative changes that increase the membrane permeability

XXII

(Evans, 1988). However, the highest activities are in the liver, heart, skeletal muscle and

erythrocyte. A rise in SGOT activities occurs in acute and occasionally in chronic liver disorders

in cattle, but remarkably higher values has been recorded in muscle damage (Petrie, 1987). On

the contrary, SGPT is present in very high amounts in the liver and kidney with smaller amounts

in the skeletal muscle and heart. Its intracellular location is predominantly cytosolic. Also, trace

amounts are present in the pancreas, spleen and lungs. SGPT rises sooner, faster and higher than

SGOT in hepatocellular disorders (Oser, 1971). The transaminase activity is reported to vary

with age, productive function and day of collection (Kaneko, 1980).

The serum protein level indicates the balance between anabolism and catabolism of

protein in the body. The plasma protein concentration at any given time in turn is a function of

hormonal balance, nutritional status, water balance and other factors affecting health (Mehra et

al., 2005). The probable cause of increase in serum total proteins could be the efficiency of

protein synthesis (Mullen, 1976 and Tennant, 1997). These results clearly indicate hepatic health

and it is hereby concluded that these liver function tests can be reliable indicators of hepatic

insufficiency in buffaloes when interpreted in conjunction with clinical symptoms. Serum

albumin is synthesized by the liver. It is catabolized by a wide variety of tissues and is an

abundant plasma protein. Serum albumin supplies readily available pool of amino acids to meet

tissue needs depending upon the nutritional status. Its synthesis is diminished during fasting,

malnutrition, hormonal imbalances and poor condition of the liver and the serum globulins,

mainly the α and β globulins are increased in acute inflammatory conditions such as acute

hepatitis and glomerulonephritis and the γ globulins are mainly related with the immuno-status

of the animal (Jain, 1986).

Rosenberger (1979) stressed that total bilirubin content of bovine serum is an important

liver function test. Reports of hypoproteinaemia in liver disease in various species of domestic

animals/calves are there in literature viz. Keskar et al., 1995 (buffalo calves); Kumar and

Srivastava, 2001(sheep) and Nasare et al. 2001 (goats).

Thyroid Hormones

It is well known that T3 is physiologically more active than T4, and provides a better

indication of the metabolic status of the animal (Shukla et al., 1994). Thus the serum T3 and T4

concentrations seem to be significantly related to the growth and age of the animal. The effects

of thyroid hormones are increasing the basal metabolic rate, making more glucose available to

XXIII

meet the elevated metabolic demands by increasing glycolysis, gluconeogenesis and glucose

absorption from the intestine, stimulating new protein synthesis, increasing lipid metabolism and

conversion of cholesterol into bile acids and other substances, activation of lipoprotein lipase and

increasing the sensitivity of adipose tissue to lipolysis by other hormones, stimulating the heart

rate, cardiac output and blood flow and increasing neural transmission, cerebration and neuronal

development in young animals (McDonald and Pineda, 1989).

Elevated hormonal pattern of ruminants regulate growth and protein metabolism by

regular supply of nutrients and also altered the amino acid absorption which affect the protein

gain and improve the body weight gain (Barry et al., 1982). Growth, metabolism, lactation and

maturation are influenced by thyroid hormones reported by Akasha et al., (1987). Metabolically

nutritional status of ruminants can be identified with the help of circulating thyroid hormones

(Todini et al., 2007). Similarly, plasma thyroid hormones i.e. tetraiodothyronine or thyroxin (T4)

and 3-3-5-triiodothyronine (T3) hormone concentration is correlated with feed intake in

ruminants. So, circulating thyroid hormones represent a relevant metabolic index of the animal’s

nutritional state. An unaltered thyroid level is a n indicator of no effect of CSL on different

hormone levels in cow. Protein-deficient diets in animals increased T3 and decreased T4 and free

T4 than control diets (Portman et al., 1985) this is the indication of fulfilling the nutrients

requirements of buffaloes with CSL. Similar finding was supported by Barth et al., (1990) who

reported that feeding regimens like dietary protein unaltered T3 and free T3 concentration was

due to higher dietary protein.

Milk yield and composition

Byproducts of agro industry played a very vital role in the milk yield parameters. Nisa et

al., 2002 reported a higher yield, fat and protein contents of the cows fed on varying levels of

urea treated wheat straws ensiled with or without corn steep liquor. They further reported a

higher total bacterial count, per ml viable and cellulolytic count in animal fed diets containing

urea treated corncobs ensiled with corn steep liquor. Similar results were reported by

Kanjanaputhipong and Leng (1998). The improved synchronization of nutrients both at ruminal

and cellular levels and thus improved utilization of N from corn steep liquor plus urea treated

corncobs for milk protein synthesis may also be supported by the highest milk CP as a

percentage of total CP intake in buffaloes fed diets containing corn steep liquor.

XXIV

Cruz et al., (2005) reported that milk production increased when fed condensed corn

distillers soluble, but there was no advantage of feeding the higher instead of lower amounts.

This finding agreed with Huhtanen and Miettinen (1992), who observed increased production

when cows were fed 5.9% of their feed DM as wet distiller solubles, but no additional production

when fed up to 17.5% of the ration DM as solubles. Increased production because of added fat

diets has been observed in several studies (Palmquist and Jenkins, 1980; Schingoethe and

Casper, 1991). Fat contained in the condensed corn distiller soluble diets was likely a

contributing factor for greater production from cows fed the condensed corn distillers soluble

diets and likely contributed to the increased milk production that often occurs when cows are fed

distillers grains with solubles (Schingoethe, 2004).

Cows fed wet corn glutten feed or soybean hulls with corn steep liquor produced 9 and

6.5% more milk, respectively than cows fed the C diet, but these increases were not statistically

different, likely because of the number of cows used and the contribution of tissue mobilization

to mammary function (Wickersham et al., 2004). Wet corn gluten feed (VanBaale et al., 2001)

and soybean hulls with corn steep liquor (DeFrain et al., 2002b) have been reported to improve

milk yield by cows. The numerical increase in energy corrected milk; (Orth, 1992) across diets

was less than that observed for actual milk yield because fat concentration was lower in milk

from cows consuming wet corn glutten feed or soybean hulls with corn steep liquor. Wet corn

gluten feed has been reported to increase milk fat percentage (Staples et al., 1984) when it

replaced concentrate in the diet, likely because of an increase in dietary NDF at the expense of

non-fermentable carbohydrates. VanBaale et al. (2001) fed similar diets and reported no

differences in fat concentration in milk from primiparous cows; however, milk fat percentage,

but not yield, was depressed in milk from multiparous cows during mid-lactation when wet corn

glutten feed was included in the diet.

Feeding mid-lactation dairy cows diets containing 20.7% soybean hull with corn steep

liquor or 14.3% pelleted soybean hull (DM basis) increased the yield of milk and milk CP, solid

not fat (SNF), lactose, and urea N (De Frain et al., 2002b). The tendency for an improvement in

the efficiency of ECM production suggests soybean hull with corn steep liquor has the potential

to improve diet digestibility.

Milk yield (kg/d) and CP content in milk has been reported to be significantly higher in

cows fed urea treated corn cobs ensiled with enzose compared to those fed on control diet (Khan

XXV

et al., 2004). However, fat, solid not fat, total solid and non-protein nitrogen content in milk were

observed similar across all treatments. This was because of increased digestible NDF and ADF

intake. Cant et al. (1993) reported that cows performed better when fed highly digestible fiber by

increasing dry matter intake (DMI) and milk production. The increased CP contents in the milk

of cows fed enzose treated diets may be attributed to increased bypass protein supplied in these

diets when compared to other diets. This increased bypass protein might have supplied amino

acids in proper amount and proportion for milk protein synthesis. An increase in cellulolytic

population might have resulted after feeding of diets containing urea treated corn cobs ensiled

with enzose that might have resulted in proper synchronization and utilization of nutrients at

ruminal level (Kanjanapruthipong and Leng, 1998).

Decreased milk yield has been observed by Sarwar et al., 2007 which has been due to

decreased DM intake, which ultimately reduced milk production. These results have been

reported by many researchers, who reported increased milk fat% in response to enzose addition

in the ration.Virtanen (1966) was awarded a Nobel Prize for his fascinating work on protein free

rations in which he demonstrated almost 100% substitution of protein by urea and other NPN

sources. The best cows produced 6,576 kg of milk, calculated on protein basis and 6,980 kg milk

on energy basis annually (365 days). On an average, a 5000 kg milk yield (over 305 days

lactating period) was routinely achieved (Cheema and Muller, 1983). Cameron et al. (1991)

reported that milk yield was greater for cows fed diets containing urea, however, 4% fat

corrected milk (FCM) yield was not affected when urea was supplemented to the diet of cows

fed a more degradable source of supplemental CP (Kung et al., 1983; Wohlt et al., 1978). The

yield of CP in milk was increased but the percentage of CP was not altered by feeding urea.

Yields and percentages of fat and SNF in milk were not altered by supplementing diets with

urea.

Broderick (1986) reported that the body weight, milk yield, FCM yield, fat, protein and

lactose were the highest in cows fed diets supplemented with protein sources when compared to

those fed diets containing urea. However, milk yields and milk components were non-significant

across all diets. The concentrations of fat, protein and lactose in milk were not altered by

treatment. Body weight gain was reported significantly better in dairy cows fed diets containing

true protein sources than those fed diets containing urea.

XXVI

Supplementing diet with urea did not alter yields and percentages of fat and SNF in milk.

These results were in agreement with previous reports (Wohlt et al., 1978, Kung and Huber,

1983) showing that supplementing diets with urea did not considerably affect milk composition.

It may be concluded from these results that urea supplementation to dairy cows increases the

milk, fat and protein production but milk composition remained unaltered.

Milk urea nitrogen

Milk urea nitrogen (MUN) is directly related to BUN level (Rook and Thomas, 1985).

While passing through blood, urea can diffuse into milk. Milk urea nitrogen level can be

regulated by balancing soluble carbohydrate and protein ratio in feed. Lower MUN concentration

indicates lower ruminally degradable protein or excess of soluble carbohydrate in the ration.

Whereas, reverse is true for higher MUN concentration. Higher concentration of ruminally

degradable protein results in higher ruminal ammonia production resulting in increased BUN

which ultimately reflects in higher MUN (Broderick et al., 1993). However, despite of ruminally

degradable protein, excessive ruminally un-degradable protein or protein in general can also

result in higher MUN concentrations (Young, 2001). This might be related to deamination of

surplus amino acids resulting in higher BUN and ultimately reflecting in higher MUN. While

Broderick et al. (1990) reported MUN and BUN are the useful indices of ruminal NH3

concentration at similar dietary CP percentage.

Hassan et al. (2011) reported higher MUN level in buffalos fed diets containing WS

treated with urea 4%, molasses 4% and 30% cattle manure. They further stated that higher MUN

was due to higher NH3 production in rumen as excessive amount of NH3 is absorbed in blood

circulation and then released in milk (Hassan et al., 2011). Rook and Thomas (1985) reported a

linear increase in MUN with increasing (from 0 to 30%) cattle manure level in diet. While,

Sarwar et al. (1997) reported higher MUN in cattle fed urea treated silage as compared to the

control.

XXVII

Chapter 3

Influence of varying levels of Corn Steep Liquor on nutrients intake,

nutrients digestibility and growth response in growing nili-ravi

buffalo calves

Abstract

This study was planned to examine the influence of varying levels of corn steep liquor

(CSL) on feed intake and growth performance of growing Nili-Ravi male buffalo calves. Fifty

male buffalo calves of 9 month old were randomly divided into five groups, 10 animals in each

group, using Randomized Complete Block Design. Five isonitogenous (16% CP) and isocaloric

(2.6 Mcal/kg) diets were formulated. The control diet (C) had 0% CSL and in CSL20, CSL40,

CSL60 and CSL80 diets, 20, 40, 60 and 80% urea on nitrogen equivalent was replaced by CSL,

respectively. Animals were given weighed amount of feed twice daily at ad libitum. The daily

feed offered and refusals were recorded to calculate dry matter intake (DMI). The sample of feed

offered and refusal were used to determine dry matter (DM), crude protein (CP), neutral

detergent fiber (NDF) and acid detergent fiber (ADF). Animals fed CSL40 diets ate highest DM

(3.33 kg daily) and was the lowest (3.16 daily) by those fed CSL80 diets. The NDF and ADF

digestibility was higher (P<.05) in animals fed diets containing CSL than those fed diet

containing 0% CSL. However, DM and CP digestibility remained unaltered (P>0.05) across all

diets. Calves fed CSL40 gained more (P<0.05) weight (757 g/day) than those fed CSL80 diet

(637 g/day). Feed cost per Kg weight gained was higher (PKR 80.79) in calves fed CSL0 diet;

however feed conversion ratio was better in calves fed CSL40 diet(4.89) than those fed CSL20,

CSL60 and CSL80 diets. Pre slaughter weight of animals fed CSL40 diet was the highest (141.5

kg) and was the lowest (130 kg) in those fed CSL80 diet. Warm carcass weight was higher

(P<0.05) in animals fed CSL40 (65.8 kg) diet followed by those fed CSL60, CSL80, CSL20 and

C diets. Dressing percentage, skin, feet weight, and weight of all body organs remained unaltered

across all diets. Similarly primal cuts, ash, Na, K and Ca remained unchanged across all diets.

The red blood cell count, white blood cells, packed cell volume and hemoglobin values were also

same across all diets. In conclusion, animals fed CSL40 diet gained more weight and were cost-

effective when compared to those fed CSL0, CSL20, CSL60 and CSL80 diets.

XXVIII

Introduction

Increasing prices of feed ingredients are making livestock keeping unaffordable by the

resource poor livestock farming community of the country. This farming community is

maintaining more than 80% of country’s livestock (Garcia et al., 2003). This increased feed

ingredient cost coupled with feed shortage has not only worsened feed availability but it has also

adversely affected profitable livestock production. This situation reduces animals performance

which are already under fed (Sarwar et al., 2004a). This feed shortage situation can be improved

through many ways but addition of new feed ingredients in the national feed inventory after the

determination of their nutritional value seems promising.

Many agro industrial byproducts, including molasses, rice polishings, wheat bran,

sugarcane pith, oil cakes and meals, hulls, corn industry byproducts etc., have already been

added. Their inclusion in feed formulation has not only enhanced animal productivity but it has

also improved feed value (Khan et al., 2004) and reduced animal feeding cost (Sindhu et al.,

2002), because more than 70% cost of any livestock enterprise is incurred on feed (Nisa et al.,

2004). Thus, exploring new feedstuffs, their chemical and biological evaluation for livestock will

open new avenues to reduce the feed shortage.

One of the byproducts of corn industry is CSL which may offer a promising protein

alternate (Nisa et al., 2004) provided nutritionally evaluated. It is a byproduct of wet corn milling

industry and is high (40%) in CP. The CSL is a good source of carbohydrates, essential amino

acids, peptides, organic compounds, magnesium, phosphorous, calcium, potassium, chloride,

sodium, sulfur and myo-inositol phosphates (Nisa et al., 2004, Hull et al., 1996). It contains 50%

DM, 10% ash and 16% nitrogen free extract (NFE). Its pH is 3.7 and it contains 21% lactic acid

(Khan et al., 2004). It is high in K which limited its inclusion in ruminant feed (Andrew and

Tom, 2013) because K is bitter in taste that reduces feed consumption when high levels of CSL

are used (Andrew and Tom, 2013). However, the scientific evidence regarding the influence

feeding high level of dietary CSL on feed intake, digestibility, weight gain and meat quality in

ruminants is limited. Therefore, present study was planned to evaluate the effect of CSL on

nutrients intake and their digestibility, weight gain, hematology and carcass quality of growing

male buffalo calves.

XXIX

MATERIALS AND METHODS

This experiment was conducted at Animal Nutrition Research Centre, University of

Agriculture, Faisalabad, Pakistan. Faisalabad is located at latitude 31°25`0``North and Longitude

73°6`0``East and altitude (elevation) 214 meters. The average annual rainfall is 350 mm and

mean temperature is 24.50ºC (Aheer et al., 2008), highest in June-July and lowest in December –

January.

Animals, diets and data collection

In this experiment, 50 buffalo calves of 9 months old were randomly divided into 5

groups, 10 animals in each group, using Randomized Complete Block Design. Five isonitogenous

(16% CP) and isocaloric (2.6 Mcal/kg) diets were formulated. The control diet (C) had 0% CSL

and in CSL20, CSL40, CSL60 and CSL80 diets, 20, 40, 60 and 80% urea on nitrogen equivalent

was replaced by CSL, respectively (Table 3.1). Animals were treated against all internal and

external parasites and vaccinated against local diseases (Hemorrhagic Septicemia, Foot and

Mouth Disease) before the start of experiment. The experiment lasted for 90 days including an

adaptation period 20 days.

Calves were housed on a concrete floor in separate pens and no mechanical means were

used to control the house temperature. Relative humidity and temperature during the experiment

remained 66.27±6.11% and 38.21±4.21°C, respectively. Feed was offered twice (0600 and 1400

h) a day and calves were fed at ad libitum. Feed offered and refused were weighed to calculate

the dry matter intake (DMI). Digestibility trials were conducted for 7 days after every 30 days.

Total three digestibility trials were conducted during the whole experiment. The digestibility trial

comprised of 7 days (3 days preliminary period and 4 days for quantitative period) for complete

collection of feces and urine. During collection period, calves were fed 10% less feed in order to

avoid refusal. Samples of feed offered and refused were collected for analysis. During collection

periods, complete collections of urine and feces were made according to the procedure described

by Williams et al. (1984). The feces of each animal were collected daily in specially designed

drum, weighed; mixed thoroughly and 20% of it was sampled and dried at 55°C. At the end of

each collection period, dried fecal samples were composited by animal and 10% of the

composited samples of each animal were taken for analysis. Small special metal buckets fitted

with a plastic pipe were made for urine collection. This plastic pipe ended in a large container.

Before collection periods, the urine excreted by a calf was measured for three days to assess its

XXX

volume in 24 hours. This was done to know the amount of 50% H2SO4 to be added to maintain

urine pH at about 4.0 which minimizes the escape of urinary ammonia nitrogen (Shahzad et al.,

2008a).This measured amount of 50% H2SO4 was added into cylinders and whole day urine

excreted by a calf was recorded. After weighing the urine voided by each animal in 24 hour, 20%

of it was sampled and preserved at -20°C (Shahzad et al., 2008a). At the end of each collection

period, the frozen urine samples were thawed and composited by animal and 10% of the

composited urine sample was used for N analysis.

Feed and fecal samples were analyzed for DM (AOAC, 1990) and CP (method of micro

Kjeldhal, AOAC, 1990). ADF was determined by using acetyletrimethyle ammonium bromide

detergent in 0.5 M sulfuric acid (Goering and VanSoest, 1970) whereas NDF was determined by

using sodium sulfite (VanSoest et al., 1991).

Carcass Characteristics

At the end of the trial, three animals from each group were slaughtered for evaluation of

carcass characteristics. Calf body weight was recorded before slaughter. After slaughter, blood

was collected. Weight of different components of offal was recorded. These included external

organs (skin, head, and feet), thoracic organ (heart, lungs+trachea) and viscera (digestive tract,

liver and kidney). All organs of digestive tract (reticulo-rumen+omasum (rumen), abomasum,

and intestine) were weighed with or without digestive contents. Warm carcass weight (WCW)

was also recorded. Dressing percentage was calculated following the procedure described by Atti

et al. (2004). Carcass was split longitudinally into two halves. The left half-carcass was cut into

primal cuts according to the method described by Diaz et al. (2002). Every cut was weighed and

dissected in fat, muscles and bones. Other tissues such as tendons, lymph nodes, etc. were

separated as waste. Pelvic fat was removed from the leg and kidney fat from the thoracic region.

Samples of longissimus dorsi muscles were carefully dissected, from the left side, weighed and

stored at -20°C for chemical analysis. Samples of meat were dried at 50ºC, ground (1-mm

screen), and stored for subsequent analysis. Dry matter was determined by drying meat at 80°C

until constant weight. Mineral content were determined by ashing meat at 600°C for 8 hours.

Nitrogen in meat was determined by Kjeldahal method as described by AOAC (1990). The Na

and K contents of meat were determined according to methods as adopted by Jackson (1973)

XXXI

using flame photometer whereas Ca and Mg were determined from the dry ashed (550ºC) meat

sample according to the method as described by AOAC (1995).

Hematology

In each collection period, blood samples (10 ml) were drawn from the jugular vein in two

heparinized vacuum tubes (VT-100H, Venojet, Terumo Co., Tokyo, Japan) at 3, 6, 9 and 12 h

post- feeding and were stored in cool box packed with ice bags and transported to the laboratory

for processing and analysis. Blood sample (10 mL from each animal) was collected by

puncturing jugular vein; 2mL was collected into the vaccutainers each containing 81µL of 15%

EDTA (anticoagulant) solution, while 8mL was collected in test tube to harvest the serum for

further analysis. Plasma samples were separated and frozen at -20°C within 60 minutes of

collection. Blood sample were used for red blood cells (RBC) count, White Blood cells (WBC)

count, Packed Cell Volume (PCV). Hemoglobin concentration in the blood was determined by

method described by Benjamin (1978).

Statistical Analysis

The data were analyzed using a Randomized Complete Block Design. In case of

significance, means were separated by Duncan's Multiple Range Test (Steel et al., 1997) by

using SPSS (version 17).

RESULTS

Nutrient ingestion and digestibility

The dry matter intake was the highest (3.33 kg/day) by calves fed CSL40 diet and was

the lowest (3.16 kg//day) by those fed CSL80 (Table 3.2). The CP intake was the highest

(P<0.05) in calves fed control and CSL40 diets followed by those fed CSL20, CSL60 and CSL80

diets. The NDF intake was highest (P<0.05) in calves fed CSL60 (1082.43 g/day) diet followed

by those fed CSL80, CSL20, CSL40 and C diets.

The DM and CP digestibility remained unchanged (P>0.05) in calves fed diets with

varying levels of CSL (table 4.2). However, NDF and ADF digestibility by calves fed diets

containing CSL was (P<0.05) higher than those fed C diet (Table 3.2).

XXXII

Growth performance

The daily weight gain of calves fed CSL40 diet was 756 g and animals fed C diet had 672

g (table 4.3). Cost to produce one kg live weight was higher (p<0.05) in calves fed C diet (PKR

80.1) followed by CSL20 (PKR 70.3), CSL40 (PKR 64.4) and CSL60 (PKR 59.1) & CSL80

(PKR 58.12) diets (Table 3.3). The feed efficiency was significantly different among all diets;

however, it was the best in animals fed CSL40 diets (Table 3.3).


Pre-slaughter weight, warm carcass, dressing percentage, skin, heart, liver, kidney and

heart weights remained unchanged (p>0.05) across all diets. Half carcass separable primal cuts

and its lean, fat and bone proportions also remained unaltered (Table 3.4, 3.5, 3.6).

Mineral profile of Meat

Total meat ash and its Na, K, and Ca contents (p>0.05) remained unchanged (table 3.7).

Hematological Parameters

All hematological parameters remained unaltered (p>0.05) in calves fed diets with

gradual replacement of urea by CSL. The red blood cell, white blood cells, packed cell volume

and hemoglobin values were also non-significant (p>0.05) across all diets (Table 3.8).

DISCUSSION


Feed consumption and nutrient intake increased by calves fed diets containing CSL and

this increased feed consumption can be attributed to improved ruminal fermentation. This

improved ruminal fermentation in animals fed diets containing CSL could be because CSL

supplied minerals, peptides and amino acids when compared to those fed diet containing urea.

The sugar and starch degrading bacteria require amino acids or peptides and cellulolytic bacteria

use ammonia for their multiplication (Russell et al., 1992). The CSL being good source of amino

acid and peptides might have triggered ruminal fermentation rapidly compared to diets without

CSL. The CSL also contains some fermentable energy which on hydrolysis yields keto acids.

The ruminal ammonia nitrogen coupled with keto acids might have improved nitrogen (N) and

carbon synchrony in the rumen, enhancing microbial proliferation leading to improved feed

degradation (Sarwar et al., 1991). The CSL might have an adequate nutrient supply which not

XXXIII

only enhanced microbial synthesis in the rumen but has improved feed intake because increased

microbial efficiency has been linked to increased feed intake (Haddad et al., 2005). Some

researchers have shown that bacterial growth and fermentation in the rumen are optimized when

starch and protein are synchronized in the rumen (Nocek and Russell, 1988; Hoover and Stokes,

1991).

Nutrient ingestion like overall dry matter and fiber degradation in rumen play a pivotal

role in controlling the feed intake (Baile and Forbes, 1972). Rate of microbial degradation in

rumen helps in emptying the rumen which also helps in controlling the rate of passage of

ingested feed (Mertens, 1977). The NDF, being an most important constituent of feed and forage,

ferments and passes slowly through the reticulorumen and has a larger filling effect than other

nutrients of diets (Van Soest, 1965, Martens, 1987). Many other partially filling effects

including, chewing rate, indigestible NDF fraction, particle size and contractions of reticulum

also limit the intake (Jarrige et al., 1986; Allen, 1996). Ruminant have an optimum capacity for

maximum usage of different nutrients to fulfill their productive performance. In other words, the

ability of healthy animals to metabolize feed varies with animal class and condition (Illus and

Jessop, 1996).

There had been a significant difference in digestibility of NDF and ADF by calves fed

diets containing CSL whereas digestibility of DM and CP remained unchanged across all diets.

The replacement of urea with CSL was assumed to ferment at a rate which might have ensured

sufficient gradually availability of nitrogen unit (i.e rumen ammonia), a vital requisite for

microbial multiplication. This might have enhanced rumen microbial enzyme production leading

to increased nutrient intake and digestibility (Sarwar and Nisa, 1999; Sarwar et al., 2004). This

implies that the structural carbohydrates (cellulose and hemicellulose) will be more extensively

fermented as evident by increased ADF and NDF digestibility in the present study.

Improved ADF and NDF digestibilities in animals fed CSL diets might be attributed to

improved cellulytic and proteolysis activities in rumen. Improved fiber digestion was due to

improve cellulose digestion by inhibiting the growth of lactate producing bacteria (Russell and

Stroble, 1989). In present study CSL supplementation improved the NDF and ADF digestion but

CP digestibility was unaltered in calves. Analogous findings were observed by Dinius et al.,

(1976) who reported the non-significant CP digestibility by urea supplementation. Contrary to

these findings, Muntifering et al., (1980) reported that retained N was higher with

XXXIV

supplementation of urea. Likewise, Ding et al., (2008) reported that hemicelluloses had

significantly higher digestibility in urea supplemented diets but found unaltered digestibilities of

CP, NDF, and ADF. In contrary to findings of present study, Ding et al., (2008) reported the

unaltered NDF digestibility.

The addition of CSL might have enhanced rumen microbial count (Nisa et al., 2008) and

per unit enzyme production due to availability of N in diverse forms (ammonia N, peptides and

amino acids) and keto acids (carbon skeleton) leading to increased nutrient digestibility (Sarwar

and Nisa, 1999; Sarwar et al., 2004). Availability of ammonia N, peptides and amino acids along

with fermentable energy source in CSL60 and CSL80 diets might have enhanced rumen

microbial multiplication and more enzyme synthesis leading to improved CP degradability at

ruminal level and microbial protein proportion at post ruminal level.

Growth performance

Increased weight gain in calves fed CSL containing diets was due to increased DMI. Atti

et al. (2004) also reported that growing ruminants fed concentrate increased weight gain by

stimulating rumen microbial activity, organic matter fermentation and microbial protein

synthesis. The CSL contains macro and micro nutrients which might have influenced rumen

ecology leading to increased VFA production. This might have increased ruminal microbial

amino acid flow to intestine (Shahzad et al., 2010) and increased daily weight gain may be

attributed to improved ruminal fermentation (Sarwar et al., 2004). This improved ruminal

fermentation might have yielded increased VFA production because of enhanced microbial bio-

mass resulting in increased digestion (Sarwar et al., 2004)). This might have increased post-

ruminal flow of amino acids (Weisberg et al., 1992). Increased ruminal VFA and microbial

protein’s synchrony at cellular level might have increased muscle accretion, resulting into better

weight gain (Sarwar and Nisa, 1999). Shahzad et al. (2010) also reported improved weight gain

of ruminants because of their better ruminal fermentation and increased microbial multiplication

and microbial flow to the post ruminal supply of microbial protein and amino acids. Spicer et al.

(1986) reported that 50% metabolizable protein from microbial crude protein (MCP) was

required for cost-effective growing beef animals; however, reduced weight gain in calves fed C

diet might be attributed to an inadequate supply of keto acids or imbalance between keto acids

and rumen ammonia or both.

XXXV

Better feed conversion in calves fed diets high in CSL was due to increased nutrient

utilization and weight gain. Similar results were reported by Kabir et al. (2004) who reported

improved FCR because of an optimum feed efficiency. Kabir et al. (2004) also reported that

animals fed concentrate had a better feed to gain ratio and attributed this to positive correlation

between feed efficiency and production efficiency.


Carcass characteristics include the hot carcass weight, cold carcass weight, dressing

percentage and bone to meat ratio. Dressing percentage is the weight of the carcass expressed as

a percentage of live weight (Oddy et al., 2000; Pethick et al., 2000). Different protein sources

affect the carcass characteristics and meat composition. Of the VFAs produced from ruminal

fermentation of carbohydrates, propionate is the major carbon substrate for gluconeogenesis

(Young, 1977; Russell and Gahr, 2000). The ruminal propionate concentration increases with the

fermentation of starch (Ciccioli et al., 2005; Huntington et al., 2006; May et al., 2009), thereby

increasing the amount of carbon substrate available for gluconeogenesis.

There had been a non-significant difference in the carcass characteristics by calves across

all diets. Non significant effects of carcass quality by calves fed CSL diets reflect the suitability

and potential of CSL as a suitable ingredient to replace urea. Furthermore, encouraging effects of

CSL also elucidates the absence of any undesirable constituent in it (Shahzad et al., 2010).

However, Oddy et al. (2000) and Pethick et al. (2000) attributed the trend for decreased intra

muscular fat to increased DMI. The results of the present study are in line with those of Salim et

al. (2014) who did not observe any difference in carcass characteristics of calves fed corn

distiller grains plus solubles (CDGS). Moreover, lean proportion was not different but fat

proportion decreased and bone proportion increased with increasing inclusion of CDGS. Shahzad

et al. (2010) reported that the carcass fatness is influenced by energy and protein density of the

finishing calves. Relationship between frame size and growth rate is affected by the energy and

protein contents of the finishing diet (Pethick et al., 2000). Smith and Crouse (1984) illustrated

that glucose was the primary energy substrate used for intramuscular adipogenesis and

hypothesized that increased ruminal propionate production may be the mechanism by which

cattle improve marbling scores compared to animals those were fed fiber in their diets. Growth

of muscle tissues and extent and site of marbling in carcass affects the value and mass of meat in

XXXVI

ruminant animals (Mahgoub et al., 1978; Butterfield et al., 1988; Hogg et al., 1992; Rayn et al.,

2007).

Primal cuts and its composition

There was non-significant difference in primal cuts and their composition of lean, meat

and bone by claves across all diets. High carcass yield and distribution of carcass tissues in

ruminants can be achieved by devising different strategies of energy and protein supplementation

(Butterfield et al., 1988; Hogg et al., 1992; Rayn et al 2007). The maturation of tissue is in the

order of bone, lean and fat (Rouse et al., 1970). Similarly, in all species, bone is early developed

tissue and does not depend on feeding regimens but muscle especially fat depots depend on

nutrient utilization (Atti et al. 2004). Likewise, bone, muscle and adipose tissue weight did not

depend on the increase of CP level in diet as reported by Negesse et al., (2001). In present study

the unaltered effect of different CSL levels in buffalo calves indicate that this ingredient has no

varying effects on fat components (Shahzad et al., 2010). The similar finding was reported by

some researchers (Soeparno and Davies, 1987; Shadnoush et al., 2004) who reported that

varying nutrients with different protein levels has no effect on meat characteristics in ruminants.

Hematological parameters

There had been a non-significant difference in hematological parameters by calves across

all diets. The non-significant difference in RBC count by calves fed CSL diets was supported by

Aboderin and Oyetayo (2006) who reported that protein levels had non-significant effect on

RBC. Similar finding was also reported by some other researchers like Belewu et al., (2008) and

Nikokyris et al. (1999) who found non-significant difference in RBC count in ruminants.

The WBC or leukocytes are immune cells (Lafleur, 2008) and play an important role in

defending the biological system against different diseases (Scholm et al., 1975). If their

concentration becomes lower, it increases chances of infectious or anomalies. The higher

concentration of WBCs had been observed in a study when different levels of energy and protein

were fed (Paryad and Mahmoudi, 2008, Belewu et al., 2008). Contrary to this, Aboderin and

Oyetayo (2006) observed significantly higher concentration of white blood cells in animals fed

different levels of protein.

The PCV of blood is useful in detecting dehydration or normocytic normochromic

anaemias that may be indicative of certain toxicities (Scholm et al., 1975). The non-significant

XXXVII

results were also reported by Bednarek et al. (1996) who observed a non-significant difference in

erythrocytes count, hemoglobin and PCV values in calves fed varying levels of proteins.

The Hb levels increased significantly in the animals offered starch supplemented diets

(Onifade et al., 1999). Galip (2006) reported non-significant difference in hemoglobin values of

calves. Increased hemoglobin value is attributed to the urea used as NPN source that possibly

triggered hematopoiesis. Contrary to the above findings, Qureshi et al. (2001) reported

significantly (P<0.05) higher hemoglobin concentration, RBC count and PCV values in calves.

Bhannasiri et al. (1961) and MacDonald et al. (1956) reported increased hemoglobin with

advanced weight and age. These results showed that CSL had no adverse effect on hematology

of buffalo calves fed diets containing CSL.


Unaltered mineral profile (Na, K and Ca) of the meat by calves fed CSL diets is due to

similar dietary mineral composition and their transformation in meat tissue. The results of the

present study are supported by the findings of Comerford et al. (1992) and Petit and Flipot

(1992), who reported that meat composition wasn’t affected by different feeding regimens in

ruminants. Similarly, in another study, ash content of the carcasses remained unaltered as noticed

by Szabo et al. (2001). Therefore, it can be concluded that CSL can be incorporated in the diets

of male buffalo calves without any ill effects on meat quality and mineral profile.

Conclusion

It can be concluded that animals fed CSL40 diet gained more weight and were cost-

effective when compared to those fed CSL0, CSL20, CSL60 and CSL80 diets. CSL can be

incorporated in the diets of male buffalo calves without any ill effects on meat quality and

mineral profile.

XXXVIII

Table 3.1 Ingredients and chemical composition of experimental diets containing different

levels of corn steep liquor in Nili Ravi buffalo calves

Ingredients (%) Diets1

C CSL20 CSL40 CSL60 CSL80

Wheat Straw 15.0 14.0 17.0 33.5 33.0

Corn Grains 35.0 20.0 20.0 15.0 5.0

Urea 4.0 3.0 2.0 1.0 0.0

CSL 0.0 5.0 10.0 15.0 20.0

Canola Meal 0.0 0.0 3.0 4.5 6.0

Sunflower Meal 0.0 0.0 3.0 4.5 6.0

Corn Glutten 60% 0.0 0.0 2.5 4.5 5.5

Rice Polishings 24.0 28.0 15.0 4.0 4.0

Maize Bran 15.0 26.0 10.0 4.0 3.0

Enzose 3.0 0.0 13.5 10.0 13.5

NaHCO3 1.0 1.0 1.0 1.0 1.0

Salt 1.0 1.0 1.0 1.0 1.0

DCP 2.0 2.0 2.0 2.0 2.0

Chemical Composition (%)

Dry Matter 91 90.1 89.9 89.8 88.8

Crude Protein 19 19 19.1 19.1 19.1

Neutral Detergent Fiber 23.0 26.5 23.4 34.7 34.2

Acid Detergent Fiber 13.5 14.6 14.7 23.5 23.6

Metabolizable Energy,

ME (Mcal/kg) 2.6 2.6 2.6 2.6 2.6

1C, CSL20, CSL40, CSL60 and CSL80 diets contained corn steep liquor as replacement of urea at the rate of 0,

20, 40, 60 and 80% on the basis of nitrogen supply by corn steep liquor, respectively.

XXXIX

Table 3.2 Effect of varying levels of corn steep liquor when replaced with urea on nutrient

intake and their digestibility in Nili Ravi buffalo calves

Parameters Diets1

C CSL20 CSL40 CSL60 CSL80 SE

Nutrient intake

Dry Matter (kg/day) 3.24bc 3.21c 3.32a 3.29ab 3.16c 11.83

Crude Protein (g/day) 638.48a 610.66b 628.43a 609.76b 582.36c 3.20

Neutral Detergent

Fiber (g/day)

745.43e 851.17c 778.05d 1143.71a 1082.43b 23.27

Acid Detergent

Fiber (g/day)

437.54e 469.25d 488.78c 774.56a 746.94b 20.89

Nutrient digestibility (%)

Dry Matter 62.6 65.6 66.3 67.7 69.7 1.8

Crude Protein 76.6 76.5 77.2 77.3 78.0 2.2

Neutral Detergent

Fiber

55b 59a 60.2a 60.2a 61.1a 1.7

Acid Detergent

Fiber

47b 56a 55a 56a 57a 1.4

1C, CSL20, CSL40, CSL60 and CSL80 diets contained corn steep liquor as replacement of urea at the rate of 0, 20,

40, 60 and 80% on the basis of nitrogen supply by corn steep liquor, respectively.

SE Standard Error

Means within row bearing different superscripts differ significantly (p<0.05)

XL

Table 3.3 Effect of varying levels of corn steep liquor when replaced with urea on

growth performance, economic appraisal and feed conversion ratio in Nili Ravi buffalo

calves

Parameters Diets1


Weight gain (g/day) 672d 677c 756a 706b 637e 10.61

Cost2 80.79a 70.30b 64.40c 59.10d 58.12d 2.24

Feed Conversion

Ratio 5.30b 5.27c 4.89e 5.20d 5.59a 0.06


40, 60 and 80% on the basis of nitrogen supply by corn steep liquor, respectively. 2Cost (Rs) of feed to product one kg live weight

SE Standard Error


XLI

Table 3.4 Effect of varying levels of corn steep liquor when replaced with urea on carcass

characteristics in Nili Ravi buffalo calves

Parameters (kg) Diets1


Pre-Slaughter

Weight 132.5c 133.4c 141.5a 137.6b 130.0d 1.11

Warm Carcass

Weight 60.8b 61.3b 65.8a 64.5a 61.3b 0.51

Dressing Percentage (%) 45.9 46 46.1 46.3 46.2 0.24

Skin weight 14.9 15 14.9 14.9 14.9 0.06

Feet weight 4.5 4.45 4.45 4.45 4.5 0.05

Heart weight 0.75 0.76 0.75 0.75 0.74 0.01

Liver weight 2.0 2.1 2.0 2.0 2.1 0.02

Kidney weight 0.5 0.49 0.49 0.5 0.49 0.03

Lung weight 2.25 2.2 2.2 2.3 2.2 0.03


40, 60 and 80% on the basis of nitrogen supply by corn steep liquor, respectively. SE Standard Error


XLII

Table 3.5 Effect of varying levels of corn steep liquor when replaced with urea on half

carcass separable primal cuts in Nili Ravi buffalo calves

Items

(kg)

Diets1


Neck 4.9 5.1 5.2 5.2 4.9 0.061

Shoulder 5.8 5.9 6.1 6.1 5.8 0.056

Breast 6.5 6.5 6.6 6.55 6.5 0.052

Loin 3.9 3.8 4 3.9 3.8 0.074

Leg 9.9 9.9 10.1 10 9.8 0.073



SE Standard Error Means within row bearing different superscripts differ significantly (p<0.05)

XLIII

Table 3.6 Effect of varying levels of corn steep liquor when replaced with urea on primal

cuts with respective proportion of lean meat, fat and bone (as %age of primal cut) in Nili

Ravi buffalo calves

Items2 Diets1


Neck

Lean 69 67.5 66.8 68.1 68.9 1.41

Fat 6 6.9 6.4 6.4 6.2 0.21

Bone 25 25.6 26.8 25.5 24.9 1.34

Shoulder

Lean 68.35 68 67.6 67.45 67.1 1.63

Fat 6.1 6.6 6.3 6.1 6.2 0.99

Bone 25.55 25.4 26.1 26.45 26.7 0.92

Breast

Lean 59.45 58.15 58.3 57.9 58 0.62

Fat 13.9 13.5 12.25 11.85 12 0.94

Bone 26.65 28.35 29.45 30.25 30 0.78

Loin

Lean 60 62.3 63 61.4 62 0.56

Fat 11.5 11 10 10.9 10 0.81

Bone 28.5 26.7 27 27.7 28 0.79

Leg

Lean 67.1 68 68.5 67.5 67 0.99

Fat 10.50 10.9 11.1 11 10.8 1.52

Bone 22.4 21.1 20.4 21.5 22.2 0.76


40, 60 and 80% on the basis of nitrogen supply by corn steep liquor, respectively. 2Lean, fat and bone proportions expressed as %age of respective primal cut

SE Standard Error


XLIV

Table 3.7 Effect of varying levels of corn steep liquor when replaced with urea on mineral

profile of meat in Nili Ravi buffalo calves

Minerals % Diets1


Ash 1 1.1 1.1 1.1 1.15 0.029

Na 0.4 0.4 0.4 0.41 0.41 0.029

K 0.85 0.9 0.95 0.93 1.01 0.026

Ca 0.23 0.24 0.28 0.29 0.3 0.023

Mg 0.34 0.35 0.35 0.35 0.35 0.03




XLV


hematological characteristics in Nili Ravi buffalo calves

Blood

Parameter

Diets1


RBC /µL 9.3×106 9.3×106 9.5×106 9.5×106 9.4×106 0.27

WBC /µL 8.9×103 8.8×103 8.8×103 8.8×103 8.9×103 0.19

PCV % 29 29 30 30 30 0.44

Hb mg/dL 10 11 11 11 11 0.31



SE Standard Error

RBC-Red Blood Cell, WBC-White Blood Cell, PCV-Packed Cell Volume, Hb-Hemoglobin


XLVI

Chapter 4

Influence of varying levels of enzose on nutrients intake, nutrients

digestibility and growth response in growing Nili Ravi buffalo calves

Abstract

This study was conducted to examine the influence of varying levels of enzose on feed

intake and growth performance of growing Nili-Ravi male buffalo calves. Thirty five male

buffalo calves of 1 year old were randomly divided into five groups, 7 animals in each group,

using Randomized Complete Block Design. Five isonitogenous (17.5% CP) and isocaloric (2.6

Mcal/kg) diets were formulated. The control diet (C) had 0% enzose and in E20, E40, E60 and

E80 diets, 20, 40, 60 and 80% corn on energy equivalent was replaced by enzose, respectively.

Animals were given weighed amount of feed twice daily at ad libitum. The daily feed offered

and refusals were recorded to calculate dry matter intake (DMI). The sample of feed offered and

refusal were used to determine dry matter (DM), crude protein (CP), neutral detergent fiber

(NDF) and acid detergent fiber (ADF). Animals fed control diet ate highest (7.65 kg/day) DM

and was the lowest (7.39 kg/day) in animals fed E80 diets. Similarly, CP intake was higher

(P<0.05) in animals fed C diet followed by those fed E20, E60, E40 and E80 diets, respectively.

NDF and ADF intake was higher (P<0.05) in animals fed C diet followed by those fed E30, E40,

E60 and E80 diets, respectively. The DM and CP digestibility remained unaltered (p>0.05)

across all diets. The NDF digestibility was higher (P<0.05) in animals fed E40 diets followed by

those fed E20, E60, E80 and C diets, respectively. Similarly, ADF digestibility was higher

(P<0.05) in animals fed E20 diets followed by those fed E40, E60, E80 and C diets, respectively.

Calves fed control diet gained more (P<0.05) weight (801 g/day) than those fed E80 diet (770

g/day). Feed cost per Kg weight gained was higher in calves fed E40 (PKR 109.32) diet and

lowest in calves fed E80 (PKR 79.62) diet; however feed conversion ratio was better (P<0.05) in

calves fed E80 diet (6.08) than those fed other diets. Pre-slaughter weights had been non-

significant (p>0.05) across all diets. The warm carcass weight was higher (P<0.05) in calves fed

E80 diet followed by those fed C, E20, E60 and E40 diets, respectively. Dressing percentage,

skin, feet weight, all body organs, primal cuts, lean, fat and bone proportion remained unchanged

(p>0.05) across all diets. The red blood cells, white blood cells, packed cell volume, hemoglobin

XLVII

and mineral profile of meat by claves fed enzose diets remained unchanged (p>0.05) across all

diets. In conclusion, increased nutrient ingestion, utilization and weight gain reflect the

suitability and potential of enzose as an economical energy source when used to replace corn

grains upto 80% of the diet of growing male buffalo calves.

INTRODUCTION

Feed resources such as cereal grains and concentrates are not economically feasible to

feed the animals, in Pakistan, due to their high price and competitive supply for human

consumption (Tauqir et al., 2012). The feedstuffs like wheat straw, rice straw, rice husk,

sugarcane pith and other agro industrial byproudcts are low in energy and protein (Sindhu et al.,

2002). The energy and protein contents of low quality feedstuffs can be enhanced with the

supplementation of concentrates (Galloway et al., 1993). This is, however, a costly approach for

resource poor farmers. An alternative system is required to employ those feed ingredients into

the feed inventory which do not have any direct human competition (FAO, 2004). Therefore, it is

imperative to explore new livestock feed resources like corn byproducts, which could be utilized

efficiently for livestock feeding (Tauqir et al., 2012).

In order to increase profitability and reduce the demand for cereals, an alternative

approach may be the replacement of concentrates with cheaper agro industrial byproducts.

However, high cost and irregular supply of available feed ingredients not only limit animal

productivity but also increases cost of production and decreases profit margin (Sarwar et al.,

2007). This situation invites ruminant nutritionists to explore new economical suitable feedstuffs

for ruminants to alleviate the influence of costly energy feed ingredients. Agro-industrial

byproducts are good source of energy and protein and may have great potential as a feed stuff for

ruminants (Sarwar et al., 2002).

Enzose is a liquid derived from the enzymatic conversion of corn starch to dextrose. It is

a light amber color liquid. Unlike other fermentable sugars, enzose has high lactic acid (18%)

content and is a cheaper source of dextrose (Khan et al., 2004). Enzose contains 85% dextrose,

with a pH of 3.5-4.5. It is a rich source of fermentable carbohydrates and is usually inexpensive

(Sarwar et al., 2007). High buildup of lactic acid in enzose has caused the conversion of free

NH3 to NH4+ which is highly reactive and binds with fiber material (Khan et al., 2004). Enzose

can be a promising substitute of concentrate (Khanum et al., 2007) for other expensive energy

XLVIII

sources like corn grains (Khan et al., 2004) if nutritionally evaluated. In order to determine its

suitability and extent of its possible inclusion in animal diets requires a biological evaluation.

However, very less scientific information is available about the usage of enzose in animal diets

as an energy source. Therefore, the present study was conducted to evaluate the nutritive value of

enzose as an energy source to replace corn grains on nutrients intake and their digestibility,

weight gain, feed conversion ratio and hematology of growing nili-ravi male buffalo calves.






January.


In this experiment, 35 male buffalo calves of 1 year old were randomly divided into 5


(17.5% CP) and isocaloric (2.6 Mcal/kg) diets were formulated. The control diet (C) had 0%

enzose and in E20, E40, E60 and E80 diets, 20, 40, 60 and 80% corn on energy equivalent was

replaced by enzose, respectively (Table 4.1). Animals were treated against all internal and

external parasites and vaccinated against local diseases (Hemorrhagic Septicemia, Foot and

Mouth Disease) before the start of experiment. The experiment lasted for 90 days including an

adaptation period of 20 days.

Calves were housed on a concrete floor in separate pens and no mechanical means were



h) a day and calves were fed at ad libitum. Samples of feed offered and refused were collected

for analysis. Feed offered and refused were weighed to calculate the DMI. Digestibility trials

were conducted for 7 days after every 30 days. Total three digestibility trials were conducted

during the whole experiment. The digestibility trial comprised of 7 days (3 days preliminary

period and 4 days for quantitative period) for complete collection of feces and urine. During

collection period, calves were fed 10% less feed in order to avoid refusal. During collection

XLIX

periods, complete collections of urine and feces were made according to the procedure described

by Williams et al. (1984). The feces of each animal were collected daily in specially designed

drum, weighed; mixed thoroughly and 20% of it was sampled and dried at 55°C. At the end of

each collection period, dried fecal samples were composited by animal and 10% of the

composited samples of each animal were taken for analysis. Small special metal buckets fitted

with a plastic pipe were made for urine collection. This plastic pipe ended in a large container.

Before collection periods, the urine excreted by a calf was measured for three days to assess its

volume in 24 hours. This was done to know the amount of 50% H2SO4 to be added to maintain

urine pH at about 4.0 which minimizes the escape of urinary ammonia nitrogen (Shahzad et al.,

2008a).This measured amount of 50% H2SO4 was added into cylinders and whole day urine

excreted by a calf was recorded. After weighing the urine voided by each animal in 24 hour, 20%

of it was sampled and preserved at -20°C (Shahzad et al., 2008a). At the end of each collection

period, the frozen urine samples were thawed and composited by animal and 10% of the

composited urine sample was used for N analysis.

Feed and fecal samples were analyzed for DM (AOAC, 1990) and CP (method of micro

Kjeldhal, AOAC, 1990). ADF was determined by using acetyletrimethyle ammonium bromide


using sodium sulfite and amylase (VanSoest et al., 1991).


At the end of the trial, three animals from each group were slaughtered for evaluation of

carcass characteristics. Calf body weight was recorded before slaughter. After slaughter, blood

was collected. Weight of different components of offal was recorded. These included external

organs (skin, head, and feet), thoracic organ (heart, lungs+trachea) and viscera (digestive tract,

liver and kidney). All organs of digestive tract (reticulo-rumen+omasum (rumen), abomasum,

and intestine) were weighed with or without digestive contents. The WCW was also recorded.

Dressing percentage was calculated following the procedure described by Atti et al. (2004).

Carcass was split longitudinally into two halves. The left half-carcass was cut into primal cuts

according to the method described by Diaz et al. (2002). Every cut was weighed and dissected in

fat, muscles and bones. Other tissues such as tendons, lymph nodes, etc. were separated as waste.

L

Pelvic fat was removed from the leg and kidney fat from the thoracic region. Samples of

longissimus dorsi muscles were carefully dissected, from the left side, weighed and stored at -

20°C for chemical analysis. Samples of meat were dried at 50ºC, ground (1-mm screen), and

stored for subsequent analysis. Dry matter was determined by drying meat at 80°C until constant

weight. Mineral content were determined by ashing meat at 600°C for 8 hours. Nitrogen in meat

was determined by Kjeldahal method as described by AOAC (1990). The Na and K contents of

meat were determined according to methods as adopted by Jackson (1973) using flame

photometer whereas Ca and Mg were determined from the dry ashed (550ºC) meat sample

according to the method as described by AOAC (1995).

Hematology

In each collection period, blood samples (10 ml) were drawn from the jugular vein in two

heparinized vacuum tubes (VT-100H, Venojet, Terumo Co., Tokyo, Japan) at 3, 6, 9 and 12 h

post- feeding and were stored in cool box packed with ice bags and transported to the laboratory

for processing and analysis. Blood sample (10 mL from each calf) was collected by puncturing

jugular vein; 2mL was collected into the vaccutainers each containing 81µL of 15% EDTA

(anticoagulant) solution, while 8mL was collected in test tube to harvest the serum for further

analysis. Plasma samples were separated and frozen at -20°C within 60 minutes of collection.

Blood sample were used for RBC count, WBC count and PCV. Hemoglobin concentration in the

blood was determined by method described by Benjamin (1978).

Statistical Analysis




RESULTS


Animals fed control diet ate highest (7.65 kg/day) DM and was the lowest (7.39 kg/day)

in animals fed E80 diets. Similarly, CP intake was higher (p<0.05) by animals fed C diet

followed by those fed E20, E60, E40 and E80 diets, respectively. The DMI was the highest

(p<0.05) by (7.65 kg/day) calves fed C diet and was the lowest (7.39 kg/day) by those fed E80

diet (Table 4.2). NDF and ADF intake was higher (p<0.05) by animals fed C diet followed by

LI

those fed E30, E40, E60 and E80 diets, respectively. The DM and CP digestibility remained

unaltered (p>0.05) across all diets. The NDF digestibility was higher (p<0.05) by animals fed

E40 diets followed by those fed E20, E60, E80 and C diets, respectively. Similarly, ADF

digestibility was higher (p<0.05) by animals fed E20 diets followed by those fed E40, E60, E80

and C diets, respectively (Table 4.2).

Growth performance

The daily weight gain by calves fed E0 diet was 801 g and animals fed E40 had 604 g

(Table 4.3). Cost to product one kg live weight was the highest (p>0.05) in calves fed E40 diet

(PKR 109.32) as compared to those fed other diets with gradual replacement of corn grains by

enzose. Better FCR was observed in calves fed diets containing higher concentration of enzose

as replacement of corn grains (Table 4.3).


Pre-slaughter weight, warm carcass, dressing percentage, skin, heart, liver, kidney and

heart weights remained unchanged (p>0.05) across all diets. Half carcass separable primal cuts

and its lean, fat and bone proportions also remained unaltered (Table 4.4, 4.5, 4.6) in animals

across all diets.


Total meat ash and its Na, K, and Ca contents (p>0.05) remained unchanged (Table 4.7).

Hematological Values

All hematological parameters remained unaltered (p>0.05) in calves fed diets with

varying levels of enzose. The red blood cell, white blood cells, packed cell volume and

hemoglobin values were also non-significant (p>0.05) across all diets (Table 4.8).

DISCUSSION


The dry matter intake is the steadfast index of nutrient intakes in ruminants and it plays

an important role in determining the feed intake of ruminants (Ketelaars and Tolkamp, 1992).

There had been a significant difference in nutrient intake by calves fed enzose supplemented

diets. Higher nutrient intake by calves fed enzose diets may be attributed to enhanced

digestibility of these nutrients and thereby improved voluntary feed intake (Hogon, 1996). A

faster digestion rate of the potentially digestible feed promoted DMI in ruminants (Sarwar et al.,

LII

1991). In present study, the replacement of enzose with corn grains was expected to ferment

rapidly in the rumen that might have ensued sufficient availability of keto acids (i.e. carbon

skeleton), a vital requisite for microbial multiplication which might have enhanced rumen

microbial enzyme production leading to increased nutrient digestibility and intake (Nisa et al.,

2004a; Nisa et al., 2004b; Sarwar et al., 2004). Moreover, high feed intake was due to more

microbial protein synthesis in the rumen and more flow of amino acids toward duodenum

(Weisbjerg et al., 1992).

Nutrient ingestion like overall dry matter and fiber degradation in rumen play a pivotal

role in controlling the feed intake (Baile and Forbes, 1972). Rate of microbial degradation in

rumen helps in emptying the rumen which also helps in controlling the rate of passage of

ingested feed (Mertens, 1977). The NDF, being an most important constituent of feed and forage,

ferments and passes slowly through the reticulorumen and has a larger filling effect than other

nutrients of diets (VanSoest, 1965, Martens, 1987). Many other partially filling effects including,

chewing rate, indigestible NDF fraction, particle size and contractions of reticulum also limit the

intake (Jarrige et al., 1986; Allen, 1996). Ruminant have an optimum capacity for maximum

usage of different nutrients to fulfill their productive performance. In other words, the ability of

healthy animals to metabolize feed varies with animal class and condition (Illus and Jessop,

1996).

A higher trend had been observed in NDF and ADF digestibility by calves fed enzose

diets. This increased digestibility may be due to readily fermentable carbohydrates supplied by

enzose which might have resulted in increased ruminal fermentation and ruminal microbial

activity which subsequently increased nutrient digestibility. Doyle and Panday (1990) also

reported an increased digestibility of DM, CP and NDF by supplementation of readily

fermentable carbohydrates (molasses). Findings of this study are in concordance with Kozloski

et al. (2006) who noticed that readily fermentable carbohydrates improved DM and organic

matter (OM) digestibility in ruminants. An enhanced fiber digestion has also been reported by

some other workers who stated that supplementation of readily fermentable carbohydrates

stimulate fiber digestion by reducing the lag time (Cheng et al., 1977; Hiltner and Dehority,

1983; Wanapat et al., 1985; Galloway et al., 1991). O’Kiely (1991) and Moore and Kennedy

(1994) also reported that fermentable carbohydrates (molasses) stimulated better microbial

LIII

activity which resulted in improved Organic matter digestibility (Nisa et al., 2004; Sarwar et al.,

2004).

Growth performance

There had been a significant difference in growth performance by claves across all diets.

This increasing trend in weight gain may be attributed to better volatile fatty acid production by

rumen microbes (Nisa et al., 2004a). Another reason may be the post rumen supply of amino

acids due to efficient microbial proliferation and feed utilization (Nisa et al., 2004a; Nisa et al.,

2004b; Sarwar et al., 2004: Mukhtar et al., 2010; Khalid et al., 2011). Results of this study

supported the findings of Brooks and Iwanaga (1967) who reported enhanced weight gain in

animals fed diets containing a fermentable energy source (molasses). Houdijk (1998) noticed that

incorporating fermentable carbohydrates in an animal’s diet results in efficient utilization of

excess indigestible protein which would otherwise be used to produce energy. It also results in

beneficial alteration in composition of microbial population as indicated by lower ammonia and

higher VFA concentrations (Konstantinov et al., 2004). Microorganisms may have retained a

greater quantity of N in the gut for their own growth (Sauer et al., 1980) resulting in utilization

of N in the cecum and colon (Kass et al., 1980; Rowan et al., 1992) which results in improved

weight gain by the animal.

Better feed conversion in calves fed diets high in enzose was due to increased nutrient

utilization and weight gain. Similar results were reported by Kabir et al. (2004) who reported

improved FCR because of an optimum feed efficiency. Kabir et al. (2004) also reported that

animals fed concentrate had a better feed to gain ratio and attributed this to positive correlation

between feed efficiency and production efficiency.


Carcass characteristics include the warm carcass weight, cold carcass weight, dressing

percentage and bone to meat ratio (Atti et al., 2004). Dressing percentage is the weight of the

carcass expressed as a percentage of live weight (Shahzad et al., 2010). Unchanged effects of

carcass quality reflect the suitability and potential of enzose as a suitable ingredient to replace

corn. Furthermore, encouraging effects of enzose also imitate the absence of any undesirable

constituent of this complex carbohydrate source. Of the VFAs produced from ruminal

fermentation of carbohydrates, propionate is the major carbon substrate for gluconeogenesis

(Young, 1977; Russell and Gahr, 2000). The ruminal propionate concentration increases with the

LIV

fermentation of starch (Ciccioli et al., 2005; Huntington et al., 2006; May et al., 2009), thereby

increasing the amount of carbon substrate available for gluconeogenesis. Apart from age and

weight, different protein sources affect the carcass characteristics and meat composition (Nasir et

al., 2010). Relationship between frame size and growth rate is affected by the energy contents of

the finishing diet (Khalid et al., 2011). Growth of muscle tissues and extent and site of marbling

in carcass affects the value and mass of meat in ruminants (Mahgoub et al., 1978). Strategic

supplementation may be helpful in achieving better carcass yield in ruminants (Butterfield et al.,

1988; Hogg et al., 1992; Rayn et al., 2007). For this purpose enzose is the best options as an

energy source.

Primal cuts and its composition

High carcass yield and distribution of carcass tissues in ruminants can be achieved

through strategic feeding (Butterfield et al., 1988; Hogg et al., 1992; Rayn et al 2007). The

maturation of tissue is in the order bone, lean and fat (Rouse et al., 1970). Similarly, in all

species, bone is early developed tissue and does not depend on feeding regimens but muscle

especially fat depots depend on nutrient utilization (Atti et al. 2004). A non-significant

difference had been observed in primal cuts and their composition of lean, bone and meat

contents by claves across all diets. The similar findings were also reported by (Soeparno and

Davies, 1987; Shadnoush et al., 2004) who reported that varying nutrients with different ME

levels has no effect on meat characteristics in ruminants. In present study the unaltered effect of

different enzose levels indicate that this ingredient has no varying effect on fat components.

Likewise, bone, muscle and adipose tissue weight did not depend on the increase of CP level in

diet as reported by Negesse et al., (2001).


The hematological parameters remained unchanged in claves across all diet. The non-

significant difference in RBC by calves was supported by Aboderin and Oyetayo (2006) who

reported that protein levels had non-significant effect on RBC. Similar finding was also reported

by some other researchers like Belewu et al., (2008) and Nikokyris et al. (1999) who found non-

significant difference in RBC count in ruminants.

White blood cells or leukocytes are immune cells (Lafleur, 2008) and play an important

role in defending the biological system against different diseases (Scholm et al., 1975). If their

concentration becomes lower, it increases chances of infectious or anomalies. The higher

LV

concentration of WBCs had been observed in a study when different levels of energy and protein

were fed (Paryad and Mahmoudi, 2008, Belewu et al., 2008). Contrary to this, Aboderin and

Oyetayo (2006) observed significantly higher concentration of white blood cells in animals fed

different levels of protein.

The PCV of blood is useful in detecting dehydration or normocytic normochromic

anaemias that may be indicative of certain toxicities (Scholm et al., 1975). The non-significant

results were also reported by Bednarek et al. (1996) who observed a non-significant difference in

erythrocytes count, hemoglobin and PCV values in calves fed varying levels of energy and

protein.

The Hb levels increased significantly in the animals offered starch supplemented diets

(Onifade et al., 1999). Galip (2006) reported non-significant difference in hemoglobin values of

calves. Contrary to the above findings, Qureshi et al. (2001) reported significantly (P<0.05)

higher hemoglobin concentration, RBC count and PCV values in calves. Bhannasiri et al. (1961)

and MacDonald et al. (1956) reported increased hemoglobin with advanced weight and age.

These results showed that enzose had no adverse effect on hematology of buffalo calves fed diets

containing enzose.

Mineral profile of meat

A non-significant effect had been observed in mineral profile of meat by claves across all

diets. Unaltered mineral profile (Na, K, Ca, and Mg) of the meat is due to similar dietary

minerals composition and their transformation in meat tissue. The results of the present study

are supported by the findings of Comerford et al. (1992) and Petit and Flipot (1992), who

reported that meat composition wasn’t affected by different feeding regimens in ruminants.

Similarly, in another study, ash content of the carcasses remained unaltered as noticed by Szabo

et al. (2001).

Conclusion

The results of the present study revealed that there is nothing wrong with enzose as an

ingredient and it can be incorporated in the fattening diets upto a level of 80% without any

adverse effects on growth performance, digestibility, meat quality and mineral profile.

LVI

Table 4.1 Ingredients and chemical composition of experimental diets with varying levels of

enzose fed to Nili Ravi buffalo calves

Ingredients (%) Experimental Diets1

C E20 E40 E60 E80

Wheat Straw 20.0 20.0 20.0 20.0 20.0

Corn Grains 24.0 18.0 12.0 6.0 0.0

Urea 2.0 2.0 2.0 2.0 2.0

Canola Meal 5.0 5.5 5.5 7.0 8.0

Corn Glutten 30% 12.0 13.0 15.0 15.0 15.5

Rice Polishings 18.0 18.0 15.0 16.0 14.0

Maize Bran 14.5 13.0 15.0 11.5 12.0

Enzose 0.0 6.0 12.0 18.0 24.0

Maize Oil 1.0 1.0 0.0 1.0 1.0

NaHCO3 0.5 0.5 0.5 0.5 0.5

Salt 1.0 1.0 1.0 1.0 1.0


Dry Matter 90.0 89.5 89.1 88.6 88.0

Crude Protein 17.5 17.5 17.5 17.5 17.5




ME (Mcal/kg) 2.6 2.6 2.6 2.6 2.6

1E0, E20, E40, E60 and E80 diets contained enzose as replacement of corn grains at the rate of 0, 20, 40, 60 and

80% on the basis of energy supply by corn grains, respectively.

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Table 4.2 Effect of varying levels of enzose when replaced with corn grains on nutrient

intake and their digestibility in Nili Ravi buffalo calves

Parameters Diets1

C E20 E40 E60 E80 SE

Nutrient intake (kg/day)

Dry Matter 7.65a 7.60b 7.39d 7.53c 7.39d 28.32

Crude Protein 1.39a 1.33ab 1.29c 1.31b 1.29c 5.43

Neutral

Detergent Fiber

2.37a 2.29b 2.31b 2.21c 2.18d 18.12

Acid Detergent

Fiber

1.36a 1.33b 1.30c 1.30c 1.27d 7.8

Nutrient digestibility (%)

Dry Matter 68.2 70 69.8 70.4 69.7 2.1

Crude Protein 75.4 75.2 76.2 76.9 78.2 2.6

Neutral

Detergent Fiber

59b 61a 61.8a 60.9a 60.9a 2.1

Acid Detergent

Fiber

45b 57.2a 56.7a 55.9a 55.1a 1.8

1C, E20, E40, E60 and E80 diets contained enzose as replacement of corn grains at the rate of 0, 20, 40, 60 and 80%

on the basis of energy supply by corn grains, respectively.

SE Standard Error


LVIII

Table 4.3 Effect of varying levels of enzose when replaced with corn grains on growth

performance in Nili Ravi buffalo calves

Parameters Diets1

C E20 E40 E60 E80 SE

Weight gain (g/day) 801a 681c 604d 758b 770b 19.19

Cost2 93.22ab 105.11ab 109.32a 86.23bc 79.62c 3.7

Feed Conversion

Ratio (FCR) 5.93d 6.98b 7.70a 6.27c 6.08d 0.18


on the basis of energy supply by corn grains, respectively. 2Cost (Rs) of feed to produce one kg live weight

SE Standard Error


LIX

Table 4.4 Effect of varying levels of enzose when replaced with corn grains on carcass

characteristics in Nili Ravi buffalo calves

Parameters (kg) Diets1

C E20 E40 E60 E80 SE

Pre-Slaughter

weight

189.6 185.5 185.0 183.4 188.6 2.27

Warm Carcass

weight

91.0ab 90.9ab 88.8b 90.8ab 91.8a 0.35

Dressing Percentage 48 49 48 49.5 48.7 0.32

Skin weight 15.7 15.7 15.6 15.6 15.6 0.06

Feet weight 5.7 5.7 5.8 5.8 5.8 0.04

Heart weight 0.84 0.84 0.85 0.85 0.86 0.02

Liver weight 2.45 2.5 2.5 2.45 2.45 0.04

Kidney weight 0.6 0.6 0.59 0.58 0.6 0.01

Lung weight 2.51 2.52 2.52 2.5 2.5 0.03


on the basis of energy supply by corn grains, respectively. SE Standard Error


LX

Table 4.5 Effect of varying levels of enzose when replaced with corn grains on half carcass

separable primal cuts in Nili Ravi buffalo calves

Items

(kg)

Diets1

C E20 E40 E60 E80 SE

Neck 6.8 6.75 6.8 6.8 6.9 0.32

Shoulder 7.8 7.9 7.6 7.7 7.9 0.04

Breast 10.6 10.6 10.55 10.5 10.5 0.04

Loin 3.5 3.2 3.1 3.3 3.45 0.05

Leg 16.9 16.8 16.7 17.0 17.15 0.05




LXI

Table 4.6 Effect of varying levels of enzose when replaced with corn grains on primal cuts

with respective proportion of lean meat, fat and bone (as %age of primal cut) in Nili Ravi

buffalo calves

Items2

Diets1

C E20 E40 E60 E80 SE

Neck

Lean 63 62.5 62.8 63.1 62.9 1.46

Fat 7 7.1 6.9 7 6.95 0.31

Bone 30 30.4 30.3 29.9 30.15 1.39

Shoulder

Lean 63.55 63.15 63.6 63.65 64.1 1.83

Fat 6.90 7 6.95 6.8 7.05 1.19

Bone 29.55 29.85 29.45 29.55 28.85 1.02

Breast

Lean 56.25 56.15 56.3 56.1 56 0.82

Fat 14.1 14 14.25 14.05 14.5 0.91

Bone 29.65 29.85 29.45 29.85 29.5 0.83

Loin

Lean 62 62.3 63 63.4 62.9 0.66

Fat 10.5 10 9.9 10.9 10.65 0.91

Bone 27.5 27.7 27.1 25.7 26.45 0.86

Leg

Lean 67.1 67 66.5 67.5 67.8 1.08

Fat 11.50 11 12.1 11.35 11.9 1.62

Bone 21.4 22 21.4 21.15 20.3 0.89


on the basis of energy supply by corn grains, respectively. 2Lean, fat and bone proportions expressed as %age of respective primal cut

SE Standard Error


LXII

Table 4.7 Effect of varying levels of enzose when replaced with corn grains on mineral

profile of meat in Nili Ravi buffalo calves

Minerals % Diets1

C E20 E40 E60 E80 SE

Total ash 1.1 1.2 1.15 1.05 1.2 0.03

Na 0.4 0.4 0.45 0.45 0.5 0.02

K 0. 93 0.95 0.97 0.97 0.98 0.03

Ca 0.25 0.25 0.3 0.3 0.3 0.02

Mg 0.34 0.35 0.35 0.35 0.35 0.03




LXIII

Table 4.8 Effect of varying levels of enzose when replaced with corn grains on

hematological characteristics in Nili Ravi buffalo calves

Blood Parameter Diets1

C E20 E40 E60 E80 SE

RBC /µL 9.03x106 9x106 9.21x106 9.9x106 9.5x106 0.2

WBC /µL 9.7x103 9.8x103 9.9x103 9.7x103 9.9x103 0.1

PCV % 30 29 30 30 30 0.38

Hb mg/dL 11 11 11 11 12 0.28



RBC-Red Blood Cell, WBC-White Blood Cell, PCV-Packed Cell Volume, Hb-Hemoglobin

SE Standard Error


LXIV

Chapter 5

Influence of varying levels of corn steep liquor on nutrients intake,

nutrients digestibility, nitrogen balance, blood biochemistry and

milk composition in early lactating nili-ravi buffaloes

Abstract

This study was planned to examine the influence of varying levels of corn steep liquor

(CSL) on feed intake, nutrient digestibility, nitrogen balance, milk composition and blood

biochemistry in early lactating Nili-Ravi buffaloes. Twenty five early lactating buffaloes were

randomly divided into five groups, 5 animals in each group, using Randomized Complete Block

Design. Five isonitogenous (17% CP) and isocaloric (2.82 Mcal/kg) diets were formulated. The

control diet (C) had 0% CSL and in CSL20, CSL40, CSL60 and CSL80 diets, 20, 40, 60 and

80% urea on nitrogen equivalent was replaced by CSL, respectively. Animals were fed twice

daily at ad libitum. The daily feed offered and refusals were recorded to calculate dry matter

intake (DMI). The sample of feed offered and refusal were used to determine dry matter (DM),

crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF). The DM, CP,

NDF and ADF intake by buffaloes fed all diets remained unchanged (P>0.05). The DM and NDF

digestibility were higher (P<.05) in animals fed diets containing CSL than those fed C diet.

However, CP and ADF digestibility remained unaltered (P>0.05) across all diets. Plasma urea

nitrogen (PUN) was lowest in buffaloes fed CSL80, CSL60 and CSL40 diets and was highest in

buffaloes fed C diet. Nitrogen balance remained significant (P<0.05) higher in buffaloes fed

CSL diets as compared to those fed C diet. However, there had been a non-significant difference

in nitrogen balance in animals fed CSL20, CSL40 and CSL60 diets. Nitrogen intake, fecal

nitrogen and urinary nitrogen values remained unchanged across all diets. The blood mineral

profile remained (P>0.05) unaffected across all diets. The blood urea, alanine aminotransferase

(ALT), albumin:globulin (A/G), bilirubin direct (BD) and bilirubin indirect (BI) values remained

unchanged (P>0.05) across all diets. The creatinine, alkaline phosphatase (ALP), serum glutamic

oxaloacetic transaminase (SGOT), total protein, albumin, globulin and bilirubin total (BT) value

were higher (p<0.05) in animals fed CSL60 and CSL80than those fed C, CSL20 and CSL40

LXV

diets. The T3, T4 and their ratio remained unchanged (P>0.05) across all diets. Milk production,

its fat, protein, true protein, NPN and solid not fat values remained unaltered across all diets. The

4% fat corrected milk and lactose were higher (P<.05) in milk of buffaloes fed CSL40, CSL60

and CSL80 diets than those fed CSL20 and C diets. In conclusion, buffaloes fed diets containing

CSL ate more DMI, had higher digestibility, better nitrogen balance, produced more milk and

lower PUN than those fed C diet.

INTRODUCTION

The dairy animals require maximum DMI to meet the increased nutrient requirement for

enhanced milk yield. This increased DMI supports maximum milk production by providing

required amount of precursors for milk synthesis. In developing countries, dairy animals derive

their nutrient needs mainly from fibrous feed (Khan et al., 1999, Sarwar et al., 2002). Crop

residues especially wheat and rice straws are being recognized most important contributors to

dairy diets in developing regions of the world (Mehra et al., 2001, Man and Wiktorsson, 2001).

However, their poor nutritive value and digestibility limit their intake and adversely affect

animal performance.

In view of increasing prices of feed ingredients, dairy animals which are already energy

and protein deficient (Sarwar et al., 2004a), has further worsened the feed availability situation.

This ever widening gap can only be narrowed down by adding more nutrients in feedstuff

inventory through nutritional evaluation. This will not only help abridge the nutrient shortage

gap but will also make ration formulation more versatile. Ruminants are generally raised on

natural pasture and crop residues which are of low protein, fermentable energy and other

nutrients (Adugna and Sundstol, 2000). This results into low animal productivity because of

reduced feed intake, digestibility, fermentation and microbial nitrogen. Unless we improve

inherent poor nutritive characteristics of these feed resources (Nsahlai et al., 2000; Adugna and

Sundstol, 2000), the animal productivity cannot be improved.

In developing countries, urea is generally fed to ruminants as an economical replacement

for a part of protein in a ration. The amount of urea a ruminant animal can use depends on the

digestible energy or TDN content of the ration (Whittier, 2014). Usage of urea as a source of

NH3 is not a perfect method, as the NH3 liberated from urea because of action of ureolytic

organism is not fully fixed in the straw. The urea treated wheat straw only retained about 30-

LXVI

35% of NH3 added to the straw during treatment and the remaining 65-70% was lost to the

atmosphere (Saadullah et al., 1981). This escaped NH3 is not only a significant nitrogen (N) loss

but it also causes atmospheric pollution. Thus, it is imperative to devise some methods, which

can help save or minimize this major loss of NH3 to the atmosphere. To overcome these

problems, some researchers have tried to fix the excess NH3 in the straw by spraying some

organic acids (like formic acids and acetic acid) or inorganic acids (like H2SO4 and HCl) with

different degree of NH3 fixation (Borhami et al., 1982). However, fixing excess NH3 with acid is

costly and hazardous and thus, its use by farmers seems impracticable.

One of the byproducts of corn industry is CSL which may offer a promising protein

alternate (Nisa et al., 2004) provided nutritionally evaluated. It is a byproduct of wet corn milling

industry and is high (40%) in CP. The CSL is a good source of carbohydrates, essential amino

acids, peptides, organic compounds, magnesium, phosphorous, calcium, potassium, chloride,

sodium, sulfur and myo-inositol phosphates (Nisa et al., 2004, Hull et al., 1996). It contains 50%

DM, 10% ash and 16% NFE. Its pH is 3.7 and it contains 21% lactic acid (Khan et al., 2004). It

is high in K which limited its inclusion in ruminant feed (Andrew and Tom, 2013) because K is

bitter in taste that reduces feed consumption when high levels of CSL are used (Andrew and

Tom, 2013). However, the scientific evidence regarding the influence feeding high level of

dietary CSL on feed intake, digestibility and milk quality parameters in buffaloes is limited.

Therefore, present study was planned to evaluate the effect of CSL on nutrients intake and their

digestibility, nitrogen balance blood biochemistry, hormonal profile and milk composition in

early lactating nili-ravi buffaloes.






January.


25 early lactating Nili-Ravi buffaloes (15+5 days in milk) were randomly divided into 5

groups, 5 animals in each group, using Randomized Complete Block Design. Five isonitogenous (17%

LXVII

CP) and isocaloric (2.82 Mcal/kg) diets were formulated. The control diet (C) had 0% CSL and

in CSL20, CSL40, CSL60 and CSL80 diets, 20, 40, 60 and 80% urea on nitrogen equivalent was

replaced by CSL, respectively (Table 5.1). Animals were treated against all internal and external

parasites and vaccinated against local diseases (Hemorrhagic Septicemia, Foot and Mouth

Disease) before the start of experiment. The experiment lasted for 90 days including an

adaptation period of 20 days.

Feeding management and data collection

Animals were housed on a concrete floor in separate pens and no mechanical means were


remained 66.27±6.11% and 38.21±4.21°C, respectively. Animals were fed twice daily (0600 and

1400 h) at ad libitum. Samples of feed offered and refused were collected for analysis. Feed

offered and refused were weighed to calculate the DMI. Digestibility trials were conducted for 7

days after every 30 days. Total three digestibility trials were conducted during the whole

experiment. The digestibility trial comprised of 7 days (3 days preliminary period and 4 days for

quantitative period) for complete collection of feces and urine. During collection period, animals

were fed 10% less feed in order to avoid refusal. During collection periods, complete collections

of urine and feces were made according to the procedure described by Williams et al. (1984).

The feces of each animal were collected daily in specially designed drum, weighed; mixed

thoroughly and 20% of it was sampled and dried at 55°C. At the end of each collection period,

dried fecal samples were composited by animal and 10% of the composited samples of each

animal were taken for analysis. Small special metal buckets fitted with a plastic pipe were made

for urine collection. This plastic pipe ended in a large container. Before collection periods, the

urine excreted by an animal was measured for three days to assess its volume in 24 hours. This

was done to know the amount of 50% H2SO4 to be added to maintain urine pH at about 4.0

which minimizes the escape of urinary ammonia nitrogen (Shahzad et al., 2008a). This measured

amount of 50% H2SO4 was added into cylinders and whole day urine excreted by a buffalo was

recorded. After weighing the urine voided by each animal in 24 hour, 20% of it was sampled and

preserved at -20°C (Shahzad et al., 2008a). At the end of each collection period, the frozen urine

samples were thawed and composited by animal and 10% of the composited urine sample was

used for N analysis. Buffaloes were milked twice daily and individual milk weights were

recorded.

LXVIII

Laboratory Analysis

Dry matter was analyzed by drying it at 135°C until a constant weight was reached

(AOAC, 1990). Protein-N of the diets was analyzed using an acidified extract (20 g of fresh

sample in 200 ml of 0.01 N HCl, agitated at 21°C for 22 h) and deproteinized with trichloracetic

acid (TCA; Novozamsky et al., 1974). Nitrogen fractions (Total-N, TCA insoluble-N) were done

by the Kjeldahl method (AOAC, 1990). Crude protein was calculated by multiplying %N with

factor 6.25 (AOAC, 1990). The ADF was determined using acetyl-trimethyl ammonium bromide

detergent in 0.5 M sulfuric acid (Goering and Van Soest, 1970) whereas NDF was determined

using sodium sulfite (Van Soest et al., 1991). The analysis of milk constituent was performed on

Milko-Scan 33 for the determination of fat, protein, true protein, NPN, lactose and SNF.

Blood Sampling and Biochemical Analysis

Blood samples were collected six hours after the last feeding on this trial. Blood sample

(10 mL from each animal) was collected by puncturing jugular vein; 2mL was collected into the

vaccutainers each containing 81µL of 15% EDTA (anticoagulant) solution, while 8mL was

collected in test tube to harvest the serum for further analysis. Plasma samples were separated

and frozen at -20°C within 60 minutes of collection. Blood samples were analyzed for BUN

using Breurer & Breuer Diagnostic kit Germany (Bull et al., 1991) and creatinine according to

method described by Davies et al. (2007). Serum minerals were determined following

procedures described by AOAC (1990). Hematological analyses (complete blood count) and

blood biochemistry parameters were done by Auto Analyser BST 30 using Biometra kit.

Statistical analysis




RESULTS


The DMI, CP, NDF and ADF intakes remained unchanged (p>0.05) across all diets

(Table 5.2). The DM and NDF digestibility were the highest (p<0.05) in animals fed diets

CSL80 diets followed by CSL60, CSL40, CSL20 and C (Table 5.2) diets, respectively. However,

the DM digestibility remained unchanged in animals fed CS80, CSL60 and CSL40 diets.

LXIX

Similarly, the DM digestibility remained unchanged for animals fed CSL20 and C diets.

However, CP and ADF digestibility by buffaloes fed diets containing CSL remained (p<0.05)

unchanged (Table 5.2) across all diets.

Nitrogen balance

Plasma urea nitrogen (PUN) was lowest in buffaloes fed CSL80, CSL60 and CSL40 diets

and was highest (p<0.05) in buffaloes fed C diet (Table 5.3). Nitrogen balance higher (p<0.05) in

buffaloes fed CSL diets than those fed C diet. However, there had been a non-significant

difference in nitrogen balance in animals fed CSL20, CSL40 and CSL60 diets. Nitrogen intake,

fecal nitrogen and urinary nitrogen values remained unchanged across all diets (Table 5.3).


There had been a non-significant (p<0.05) difference in erythrocytes, absolute, white

blood cells and thrombocyte values in buffaloes across all diets (Table 5.4). A significant

difference was observed in lymphocytes, monocytes and eosinophils values in buffaloes fed CSL

diets. The highest values had been found in animals fed CSL80 diets followed by those fed

CSL60, CSL40, CSL20 and C diets, respectively. However, the values of neutrophils remained

unchanged in buffaloes across all diets (Table 5.4).

Serum Minerals

The blood mineral profile showed a non-significant (p>0.05) difference in buffaloes

across all diets. The Na, K, Ca, P, Cl and HCO3 concentration was non-significant across all

diets but the higher values of these minerals had been found in CSL supplemented diets than

those fed C diet (Table 5.5).

Blood Biochemistry

There had been a non-significant (p>0.05) difference in blood urea concentration in

animals across all diets. Similarly, alanine aminotransferase (ALT), albumin globulin ration

(A/G), bilirubin direct (BD) and bilirubin indirect (BI) remained unaltered (p>0.05) in buffaloes

across all diet. The concentration of creatinine was significantly (p<0.05) higher in animals fed

CSL diet than those fed C diet (Table 5.6). The alkaline phosphatase (ALP, serum glutamic

oxaloacetic transaminase (SGOT), total protein, albumen, globulin and bilirubin total (BT)

values were found to be significantly (p<0.05) different in animals across all diets. These values

had been noticed to be higher in animals fed CSL diets than those fed C diet. The highest B.T

LXX

value was found in animals fed CSL40 diet followed by CSL60, CSL0, CSL40 and CSL80

(Table 5.6) diets, respectively.

Thyroid hormones

The T3, T4 and their ratio remained unaltered (p>0.05) in animals across all diets (Table

5.7). The higher values had been found in animals fed CSL diets as compared to those fed C diet.

Milk yield and composition

A non-significant (p>0.05) difference had been noticed in milk yield, milk fat, milk

protein, milk true protein, milk NPN and milk SNF by animals fed CSL diets (Table 5.8).

However, 4% FCM and lactose showed a significant difference in animals across all the diet.

The higher (p<0.05) FCM value was observed in animals fed CSL60 and CSL80 diets followed

by CSL40, CSL20 and C diets. The lactose value was higher (p<0.05) in buffaloes fed CSL80

diet followed by those fed CSL60, CSL40, CSL20 and C diet, respectively.

DISCUSSION


The DM, CP, NDF and ADF intake by lactating buffaloes fed diets containing CSL

remained unchanged across all diets. Similar findings were reported by Yadave and Virk (1994),

Sarwar et al. (1994), Dass et al. (2001) and Mehra et al. (2001). This lack of difference in

nutrient intake may be because of similarity among dietary nutrients. However, Saadullah et al.

(1981), Al-Rabbat et al. (1978), Prasad et al. (1998) and Wanapat et al. (2000) reported higher

DMI by cattle fed diets containing urea. Number of factors controlled DMI in ruminants (Forbes,

1996), including physical fill (Allen, 1997; Mertens, 1994) and many metabolic-feeding factors

(Illius and Jessop, 1996). Feeds low in digestibility reduced DMI because of their slow passage

rate through the digestive tract. The reticulo-rumen and possibly the abomasum stretch and touch

receptors in their walls affecting DMI negatively as the weight and volume of digesta accumulate

(Allen, 1997). Thus, each factor might operate under some conditions, but it is most likely the

additive effect of several stimuli that regulate DMI (Forbes, 1996).

The increased DM and NDF digestibility by buffaloes fed diets containing CSL may be

because of its rapidly fermentable nature. The CSL might have ensured constant and sufficient

nitrogen availability in the rumen compared to C diet containing only urea. This might have

enhanced ruminal fermentation through increased microbial enzyme production leading to

LXXI

increased nutrient digestibility (Sarwar and Nisa, 1999; Sarwar et al., 2004). This implies that

dietary cellulose and hemicellulose get extensively fermented, enhancing NDF and ADF

digestibility in present study. The improved NDF and ADF digestibility can also be attributed to

improved cellulytic activities in rumen. Mahr-un-Nisa et al. (2004) reported that the increased

NDF digestibility could be because of its increased rate of degradation and shorter lag time of

diets containing CSL than that of control diet. Improved fiber digestion was due to improved

cellulose digestion by inhibiting the growth of lactate producing bacteria (Russell and Stroble,

1989). Dinius et al., (1976) reported the non-significant CP digestibility by urea supplementation

in ruminants. Contrary to these findings, Muntifering et al. (1980) reported that retained N was

higher with supplementation of urea. Likewise, Ding et al. (2008) reported that hemicelluloses

had higher digestibility in urea supplemented diets but remained unaltered CP, NDF and ADF

digestibility. In contrast to findings of present study, Ding et al., (2008) reported an unaltered

NDF digestibility. The addition of CSL might have enhanced rumen microbial count (Nisa et al.,

2008) and per unit enzyme production due to availability of N in diverse forms (ammonia N,

peptides and amino acids) and keto acids (carbon skeleton) leading to increased nutrient

digestibility (Sarwar and Nisa, 1999; Sarwar et al., 2004). Availability of ammonia N, peptides

and amino acids along with fermentable energy source in diets might have enhanced rumen

microbial multiplication and more enzyme synthesis leading to improved CP degradability.

Nitrogen balance

The highest nitrogen balance in buffaloes fed diet containing 80% CSL is an indication of

better nitrogen utilization. Plasma urea nitrogen (PUN) is a reliable indicator of protein status of

animals (Sykes, 1978) and it reflects ruminal NH3-N concentration because the liver removes 70

to 80% portal absorption of urea-N secreted by the liver during abnormal hepatic function

(Huntington, 1990). Higher PUN was related to ammonia absorption from rumen and

deamination of amino acids (AA) and increased the N retention (Adams et al., 1981). The PUN

was lower (P<0.05) in buffaloes fed diets with varying levels of CSL. Similarly, fecal N and

urinary nitrogen were also non-significant in animals across all diets. Significantly less values of

PUN in buffaloes fed varying levels of CSL has indicated maximum utilization of NH3 for

ruminal microbial growth (Sarwar et al., 2004). The slower release of fiber bound N was

synchronized with fiber fermentation and thus utilized by the rumen micro-flora (Nisa et al.,

2004). Slow release of NH3-N resulted in less NH3 absorption through ruminal walls that

http://jds.fass.org/cgi/content/full/90/12/5714#HUNTINGTON-1990

LXXII

consequently lowered the plasma urea N and urinary N loss and thus higher N retention in

buffaloes. Sarwar et al. (1994) reported that rapid release of NH3 in rumen was not efficiently

utilized by ruminal microbes and absorbed into the blood through the ruminal walls thereby

increasing plasma urea N and urinary N loss (Sarwar et al., 1994). Aziz et al. (1983) reported

that blood urea N increased in bulls fed diets containing urea and this high blood urea N was

presumably due to more absorption of NH3 through the rumen wall. The increased blood urea

values after feeding the urea diets probably indicated the conversion of NH3 to urea in the liver.

Broderick et al. (1993) reported that blood urea was lower (3.8 vs. 5.2 mm) when true protein

was fed than when the urea diet was fed. This finding probably was due to increased rate of

ruminal NH3 formation when urea was fed. Other researchers (Broderick et al., 1986, 1993)

described that concentrations of urea in blood implied that rumen degraded protein may have

been limiting in diets containing true protein. The diets containing CSL promoted the greatest N

retention. These results suggest that ruminal utilization of N was the lowest in animals fed diet

containing urea diets than those fed diets without urea. This indicated that N from diet containing

CSL was less rapidly available than that without CSL. The present results indicate that CSL is

very effective in enhancing utilization of N by minimizing N loss at ruminal level. The low

plasma N levels with CSL diets provide explanation of results of present study. It can be

concluded that CSL diets slow down the release of ruminal NH3 that maximizes N

synchronization with carbon skeleton and this consequently minimizes N loss from the rumen.


A non-significant effect had been observed on hematological parameters in animals

across all diets. Blood profile is an important indicator of animal health (Cheesbrough, 1991).

Packed cell volume of blood is very useful in detecting dehydration or normocytic

normochromic anemia that may be indicative of certain toxicities (Scholm et al., 1975). Platelets

are important circulating constituents of the blood and have important functions i.e. blood

clotting and hemostasis (Sunitha and Munirathnam, 2008). Platelets also release natural growth

promoters’ i.e. platelet-derived growth factor, transforming growth factor-β that helps repair and

regeneration of connective tissues. In biological system monocytes defend the tissues against

microbial agents (Scholm et al., 1975; Cheesbough, 1991). Lymphocytes play an important role

in the formation of cellular immunity and defensive system of the body (Baker and Silver, 1985).

Similar finding was supported by Nelson and Watkins (1967) who reported that blood

LXXIII

hemoglobin and hematocrit were unaffected by different feeding regimens. A non-significant

effect had been observed in differential leukocytes counts (DLC) by animals fed CSL diet as

compared to those fed C diet. These findings were supported by Khalid et al. (2011) who

reported that different feeding regimens have significant effect on different DLC values in lambs.

Likewise, Nasir et al. (2010) observed non-significant increase in neutrophils, eosinophils,

basophils, monocytes and lymphocytes. Unaltered hematology is an indicator that there are no

deleterious effects of CSL on hematology. In conclusion, hematologic picture remained

unaffected by buffaloes fed varying levels of CSL however; experimental values fell within

range value as reported by Merck Veterinary Manual (2005).

Serum Minerals

Unaltered serum minerals had been observed in animals across all diets. The result of

present study supported the findings of Cole (1992) who reported that serum Ca, P and Mg were

unaffected under different feeding regimens. Davies et al. (2007) also reported that serum Na

and K remained unaffected in ruminants.

Blood Biochemistry

The blood urea, ALT, albumin:globulin, BD and BI values remained unchanged (P>0.05)

across all diets. The creatinine, ALP, SGOT, total protein, albumin, globulin and BT values

showed a significant (p<0.05) difference in buffaloes fed CSL diets.


of the protein in the rumen and the rate of utilization of NH3 for bacterial protein synthesis. An

increase in the serum urea level may reflect an accelerated rate of protein catabolism rather than

a decrease in urinary excretion (Kaneko, 1980). The serum urea level also increases in renal


1985).

An increase in the serum creatinine levels is generally seen in degenerative muscle

diseases (Prassee, 1986). The quantity of creatinine formed each day depends upon the creatine

content of the body, which in turn depends upon the dietary intake, inhibiting the endogenous

synthesis rate and the muscle mass (Walker, 1961). Elevated creatinine levels in the

serum/plasma are also associated with various renal diseases. Creatinine is formed during the

metabolism of creatine in the muscle and its increased concentrations in the serum are the

indicator of a decreased glomerular filtration rate.

LXXIV

Transamination of amino acids is a synthetic function of hepatic cells and the enzyme

AST catalyses this reaction. Therefore elevation of serum AST is a highly sensitive indicator of

hepatic insufficiency (Hill and Kelly, 1974). The AST/ALT ratio is considered (ASPA, 1999) to

be of greater use, with respect to concentrations of each of the two enzymes, for evaluating

whether there are conditions of suffering or liver damage (Bovera et al., 2002). Among various

tissues and organs, higher ALP activities occur in the kidneys and intestines, while there are

moderate in the liver, lungs, bone, placenta and leukocytes (Cornelius, 1980). However, the use

of ALP as a diagnostic tool for detecting tissue damage is limited, especially in young growing

animals, where bone can be a very significant source of ALP (Evans, 1988). ALP plays an

important role in the regulation of cell division and growth (Swarup, 1981) and its activities

reach higher levels in the serum of growing animals. The result revealed that although the serum

alkaline phosphatase values were within the normal range, there was a gradual increasing trend

in the mean values of serum alkaline phosphatase (ALP), which could be attributed to the effect

of their normal physiological growth. On the contrary to this, Ahuja et al., 1977 did not find any

change in serum ALP activity in buffalo bulls fed on urea for a prolonged period.

Serum GOT and GPT are both cytoplasmic and mitochondrial enzymes and are

distributed in all body tissues. They are released by even mild degenerative changes that increase

the membrane permeability (Evans, 1988). However, the highest activities are in the liver, heart,

skeletal muscle and erythrocyte. A rise in SGOT activities occurs in acute and occasionally in

chronic liver disorders in cattle, but remarkably higher values has been recorded in muscle

damage (Petrie, 1987). On the contrary, SGPT is present in very high amounts in the liver and

kidney with smaller amounts in the skeletal muscle and heart. Its intracellular location is

predominantly cytosolic. Also, trace amounts are present in the pancreas, spleen and lungs.

SGPT rises sooner, faster and higher than SGOT in hepatocellular disorders (Oser, 1971). The

transaminase activity is reported to vary with age, productive function and day of collection

(Kaneko, 1980).






LXXV

and it is hereby concluded that these liver function tests can be reliable indicators of hepatic

insufficiency in buffaloes when interpreted in conjunction with clinical symptoms.

Serum albumin is synthesized by the liver. It is catabolized by a wide variety of tissues

and is an abundant plasma protein. Serum albumin supplies readily available pool of amino acids

to meet tissue needs depending upon the nutritional status. Its synthesis is diminished during

fasting, malnutrition, hormonal imbalances and poor condition of the liver and the serum

globulins, mainly the α and β globulins are increased in acute inflammatory conditions such as

acute hepatitis and glomerulonephritis and the γ globulins are mainly related with the immuno-

status of the animal (Jain, 1986).

Rosenberger (1979) stressed that total bilirubin content of bovine serum is an important

liver function test. Reports of hypoproteinaemia in liver disease in various species of domestic

animals/calves are there in literature viz. Keskar et al., 1995 (buffalo calves); Kumar and

Srivastava, 2001(sheep) and Nasare et al. 2001 (goats).

Thyroid Hormones

The T3, T4 and their ratio remained unaltered by buffaloes across all diets. The mean

values of serum T3 and T4 found in this experiment were within the normal physiological range

(Table 6.7). The serum T3 values were similar in all five groups. However, the values of T4 were

higher in animals fed CSL60 and CSL80 diets as compared to those fed other diets. This

indicated a higher basal metabolic rate in animals fed CSL60 and CSL80 diets as compared to

those fed other diets. It is well known that T3 is physiologically more active than T4, and

provides a better indication of the metabolic status of the animal (Shukla et al., 1994). Thus the

serum T3 and T4 concentrations seem to be significantly related to the growth and age of the

animal. The effects of thyroid hormones are increasing the basal metabolic rate, making more

glucose available to meet the elevated metabolic demands by increasing glycolysis,

gluconeogenesis and glucose absorption from the intestine, stimulating new protein synthesis,

increasing lipid metabolism and conversion of cholesterol into bile acids and other substances,

activation of lipoprotein lipase and increasing the sensitivity of adipose tissue to lipolysis by

other hormones, stimulating the heart rate, cardiac output and blood flow and increasing neural

transmission, cerebration and neuronal development in young animals (McDonald and Pineda,

1989). Elevated hormonal pattern of ruminants regulate growth and protein metabolism by

regular supply of nutrients and also altered the amino acid absorption which affect the protein

LXXVI

gain and improve the body weight gain (Barry et al., 1982). Growth, metabolism, lactation and

maturation are influenced by thyroid hormones reported by Akasha et al., (1987).

Metabolically nutritional status of ruminants can be identified with the help of circulating

thyroid hormones (Todini et al., 2007). Similarly, plasma thyroid hormones i.e. T4 and T3

hormone concentration is correlated with feed intake in ruminants. So, circulating thyroid

hormones represent a relevant metabolic index of the animal’s nutritional state. An unaltered

thyroid hormone level in animals across all diets is an indicator of no deleterious effect of CSL

on different hormone levels in cow. Protein-deficient diets in animals increased T3 and decreased

T4 and free T4 than control diets (Portman et al., 1985) this is the indication of fulfilling the

nutrients requirements of buffaloes with CSL. Similar finding was supported by Barth et al.,

(1990) who reported that feeding regimens like dietary protein, unaltered T3 and free T3

concentration was due to higher dietary protein.

Milk yield and Composition

The highest milk yield (13.83 Kg/day) in buffalos fed CLS80 diet than those fed C (12.73

kg/day) diet supported the findings of Wanapat et al. (1985), Man and Wiktorsson (2001); Sutton

(1989) and Cann et al. (1991) Sarwar et al. (1992) also reported that increasing dietary CSL

might have provided a better nutrient synchrony at cellular level that helps synthesized more

milk and milk constituents. The higher milk production by buffaloes may also be attributed to

increased digestible NDF intake which provided sufficient energy to support the increased milk

yield.

Milk urea nitrogen (MUN) is milk quality indicator which equilibrates with and is

proportion to blood urea nitrogen. So, this also indicates urea nitrogen status in dairy cows

(Ahlam et al., 2010). Milk urea nitrogen is the major single contributor to milk NPN. Milk urea

is derived primarily from blood urea which is produced from excess ruminal ammonia and amino

acids catabolism in liver (De Peters and Ferguson, 1992). In the mammary gland, urea diffuses

into and out of mammary gland cells, equilibrating with urea in the blood. Because of this

process, MUN equilibrates with and is proportional to BUN. The increased MUN generally

results when blood urea nitrogen is high which adversely affects animal’s reproductibility. The

findings of present study were concordant to those reported by Sutton (1989) who noticed no

change in milk protein concentration in buffaloes fed diets containing CSL. However, an

increased milk protein tendency was noticed in buffalos fed diets containing high amount of

LXXVII

CSL. This may be because of an increased cellulolytic population in rumen of those animals fed

CSL diets, improving synchronization and utilization of nutrients at ruminal level

(Kanjanapruthipong and Leng (1998). The improved synchronization and utilization of N from

CSL for milk protein synthesis was also supported by the highest milk CP as a percentage of

total CP intake in animals fed CSL based diets. However, true protein and NPN, as percentage of

milk protein did not show any treatment effect. Percent milk fat, SNF and total solid remained

unchanged across all treatments whereas lactose percentage showed a significant difference. The

results of present study were consistent to those reported by Man and Wiktorsson (2001).

Conclusion

In conclusion, buffaloes fed diets containing CSL ate more DMI, had higher digestibility,

better nitrogen balance, and produced more milk and lower PUN than those fed C diet.


corn steep liquor fed to early lactating Nili Ravi buffaloes


LXXVIII

C CSL20 CSL40 CSL60 CSL80

Wheat Straw 30.0 30.0 30.0 30.0 30.0

Corn Grains 25.0 24.0 22.0 22.0 20.0

Urea 4.0 3.0 2.0 1.0 0.0

CSL 0.0 5.0 10.0 15.0 20.0

Canola Meal 0.0 0.0 3.0 4.5 5.0

Sunflower Meal 0.0 0.0 3.0 4.5 4.0

Corn Glutten 30% 0.0 0.0 2.0 4.5 5.0

Rice Polishings 17.0 15.0 10.0 4.0 4.0

Maize Bran 15.0 14.0 9.0 4.0 3.0

Enzose 5.0 5.0 5.0 6.5 5.0

NaHCO3 1.0 1.0 1.0 1.0 1.0

Salt 1.0 1.0 1.0 1.0 1.0

DCP 2.0 2.0 2.0 2.0 2.0


Dry Matter 90 90 89.9 89.8 88.8

Crude Protein 17 17 17 17 17

Neutral Detergent Fiber 32 32.1 32.1 32.2 32.3


Non Structural

Carbohydrates 30 30 30 30 30

Metabolizable Energy

ME (Mcal/kg) 2.82 2.82 2.82 2.82 2.82

1 C, CSL20, CSL40, CSL60 and CSL80 diets contained corn steep liquor as replacement of urea at the rate of 0,


Table 5.2 Effect of varying levels of corn steep liquor when replaced with urea on nutrient

intake and their digestibility in early lactating Nili Ravi buffaloes

Parameters Diets2

LXXIX



Dry matter 17.61 17.50 17.52 17.45 17.50 0.026

Crude protein 3.00 2.98 2.98 2.97 2.98 0.022

Neutral detergent

fiber

8.51 8.57 8.56 8.50 8.62 0.025

Acid detergent

fiber

5.82 5.79 5.83 5.85 5.87 0.023

Nutrient digestibilities (%)

Dry matter 64.6b 66.3ab 67.1ab 67.9a 68.5a 0.423

Crude protein 79.9 78.2 78.2 78.3 78.0 0.287

Neutral detergent

fiber

58c 59ab 60bc 61b 62.3a 0.457

Acid detergent

fiber

43 43 44 44 44.5 1.021




SE Standard Error

Table 5.3 Effect of varying levels of corn steep liquor when replaced with urea on nitrogen

balance in early lactating Nili Ravi buffaloes

Parameters

(g/day)

Diets1


LXXX

Plasma Urea

Nitrogen, mg/dL

17.8a 16.8b 16.2bc 15.9c 15.1c 0.628

Nitrogen Intake 480 476.8 476.8 475.2 476.8 0.941

Fecal Nitrogen 416 412.8 412.8 411.2 411.2 0.233

Urinary Nitrogen 48.0 47.68 47.68 47.52 47.68 2.925

Nitrogen Balance 16c 16.32b 16.32b 16.48b 17.92a 2.845


1 C, CSL20, CSL40, CSL60 and CSL80 diets contained corn steep liquor as replacement of urea at the rate of 0,


SE Standard Error


hematological characteristics in early lactating Nili Ravi buffaloes



Erythrocytes

LXXXI

Hemoglobin (g/dl) 12.3 12.2 12.4 12.5 12.5 0.048

Hematocrit (%) 35.5 35.4 35.5 35.5 35.6 0.231

Absolute Values

Total RBC count

(m/ul)

7 7.1 7.2 7.1 7.2 0.219

MCV (fl) 59.9 55.2 61.5 59.9 58.7 0.606

MCH (Pg) 19.3 19.3 19.5 19.5 19.5 0.350

MCHC (g/dl) 34.0 34.1 34.0 34.1 34.3 0.512

White Blood Cells

(k/ul)

Total WBC Count 8.0 8.0 8.1 8.0 8.1 0.025

DLC (%)

Neutrophiles 72 74 75 76 76 0.455

Lymphocytes 45d 50c 50c 60b 65a 1.976

Monocytes 02b 02b 03a 03a 03a 0.132

Eosinophile 04c 05c 07b 07a 9a 0.561

Thrombocyte (k/ul)

Platelets Count 170 169 170 170 170 2.000

Means within row bearing different superscripts differ significantly (p<0.05) 1C, CSL20, CSL40, CSL60 and CSL80 diets contained corn steep liquor as replacement of urea at the rate of 0, 20,


RBC-Red Blood Cell, WBC-While Blood Cell, DLC-Differential Leukocyte Count, MCV-Mean Corpuscular Hemoglobin, MCHC- Mean Corpuscular Hemoglobin Concentration

SE Standard Error

Table 5.5 Effect of varying levels of corn steep liquor when replaced with urea on blood

mineral profile in early lactating Nili Ravi buffaloes

Parameter Diets1


Na (mEq/L) 133 134 133 134 134 0.702

K (mEq/L) 5.3 5.4 5.1 5.3 5.6 0.080

LXXXII

Ca (mg/dL) 9.8 9.9 9.8 9.8 9.9 0.025

P (mg/dL) 5.4 5.4 5.4 5.5 5.45 0.024

Cl (mEq/L) 106 106 104 106 105 0.305

HCO3 (mEq/L) 23 23 24 24 23 0.350



SE Standard Error

Table 5.6 Effect of varying levels of corn steep liquor when replaced with urea on blood

biochemistry in early lactating Nili Ravi buffaloes

Parameter

Diets1


Blood Urea (mg/dL) 60 62 65 72 76 2.718

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Creatinine (mg/dL) 1.4b 1.4b 1.3c 1.5ab 1.6a 0.035

Enzymes (U/L)

ALT 45 55 56 48 71 3.25

ALP 110b 102c 165a 120b 176a 8.325

SGOT 124c 146ab 169b 165ab 178a 5.594

Blood Protein (g/dL)

Total Protein 6.8c 7.6a 6.9c 7.6a 7.2b 0.092

Albumin 2.4b 2.3b 2.3b 2.4b 2.8a 0.054

Globulin 4.4b 5.3a 4.6b 5.2a 4.4b 0.107

A/G 0.5 0.4 0.5 0.5 0.6 0.027

Bilirubin (mg/dL)

B.T 0.7ab 0.6ab 0.8a 0.7ab 0.5b 0.035

B.D 0.3 0.2 0.3 0.3 0.2 0.023

B.I 0.4 0.4 0.5 0.4 0.3 0.023



ALT- alanine aminotransferase, ALP- alkaline phosphatase, SGOT- serum glutamic oxaloacetic transaminase, B.T- bilirubin total, B.D- bilirubin direct, B.I- bilirubin indirect

SE Standard Error

Table 5.7 Effect of varying levels of corn steep liquor when replaced with urea on thyroid

hormone profile in early lactating Nili Ravi buffaloes

Parameter

(nmol/L)

Diets1


LXXXIV

T3 1.75 1.8 1.85 1.9 1.8 0.025

T4 40.41 41.13 41.7 42.32 43.17 0.335

T3/T4 23.1 22.85 22.54 22.27 23.98 0.269



T3- triiodothyronine, T4- thyroxine

SE Standard Error

Table 5.8 Effect of varying levels of corn steep liquor when replaced with urea on weight

gain, milk quantity and milk composition in early lactating Nili Ravi buffaloes

Parameter Diets1


Volume (kg/d) 7.6 7.6 7.7 7.7 7.8 0.277

4% FCM 12.73c 12.92bc 13.09b 13.48a 13.84a 0.521

LXXXV

Milk Constituents (%)

Fat 6.7 6.8 6.8 7.0 7.1 0.236

Protein 3.6 3.6 3.7 3.75 3.9 0.220

True Protein 3.38 3.38 3.40 3.41 3.44 0.030

Non-Protein Nitrogen 0.22 0.23 0.24 0.24 0.24 0.004

Lactose 5.6b 5.65b 5.70ab 5.80a 5.95a 0.039

SNF 10.5 10.7 10.8 11.0 11.5 0.236



FCM-Fat Corrected Milk, SNF- Solid Not Fat

SE Standard Error

Chapter 6

Effect of varying levels of enzose on nutrient intake, nutrient

digestibility, nitrogen balance, milk composition, hormonal profile

and blood biochemistry in lactating buffalos

LXXXVI

Abstract

This study examined the influence of varying levels of enzose on feed intake, nutrient

digestibility, nitrogen balance, milk composition and blood biochemistry of early lactating Nili-

Ravi buffaloes. Twenty five early lactating buffaloes were randomly divided into five groups, 5

animals in each group, using Randomized Complete Block Design. Five isonitogenous (17% CP)

and isocaloric (2.82 Mcal/kg) diets were formulated. The control diet (C) had 0% enzose and in

E20, E40, E60 and E80 diets, 20, 40, 60 and 80% corn on energy equivalent was replaced by

enzose, respectively. Animals were fed twice daily at ad libitum. The daily feed offered and

refusals were recorded to calculate dry matter intake (DMI). The sample of feed offered and

refusal were used to determine dry matter (DM), crude protein (CP), neutral detergent fiber

(NDF) and acid detergent fiber (ADF). The DM, CP and ADF intake by buffalos fed all diets

remained unchanged (p>0.05). However, NDF intake by buffaloes was higher (p<0.05) in

animals fed C diets followed by those fed E40, E20, E60 and E80 diets, respectively. The DM,

NDF and ADF digestibility was higher (p<0.05) in buffalos fed E80 and E60 diets than those fed

E40, E20 and C diets, respectively. However, CP digestibility remained unaltered (p>0.05)

across all diets. Plasma urea nitrogen and nitrogen balance was higher (p<0.05) in buffaloes fed

E80 and E60 diets than those fed E40, E20 and C diets, respectively. Nitrogen intake, fecal

nitrogen, urinary nitrogen and blood mineral profile remained unchanged (p>0.05) across all

diets. The blood urea, creatinine, alanine aminotransferase, albumin:globulin and bilirubin direct

also remained unaltered (p>0.05) across all diets. However, alkaline phosphatase, serum

glutamic oxaloacetic transaminase, total protein, albumin, globulin, bilirubin total and bilirubin

indirect were higher (p<0.05) in animals fed E60 and E80 diets followed by those fed E40, E20

and C diets, respectively. The triiodothyronine, thyroxine and their ratio remained unchanged

(p>0.05) across all diets. Milk production, its fat, protein, true protein, non-protein nitrogen

(NPN) and solids not fat (SNF) remained unaltered across all diets. However, 4% fat corrected

milk (FCM) and lactose remained higher in animals fed E80 and E60 diets followed by those fed

E40, E20 and C diets, respectively. In conclusion, buffaloes fed diets containing enzose had

higher digestibility, better nitrogen balance, produced more milk and lower PUN than those fed

C diet.

INTRODUCTION

LXXXVII

In Pakistan, buffalo population is more than 30 million heads and is increasing at the rate

of 2% per annum (Sarwar et al., 2012). Currently more than 40 billion liters of milk is being

produced annually in the country out of which 70% comes from buffaloes (PES, 2013). The

buffalo productivity is very low and this low productivity can be ascribed to imbalance nutrition,

reproductive inefficiency, delayed maturity and poor animal growth (Shahzad et al., 2011). The

crude protein and energy are two critical nutrients and their inadequate supply adversely affects

animal productivity (Sarwar et al., 2002).

The dairy animals require maximum DMI to meet the increased nutrient requirement for

enhanced milk yield. This increased DMI supports maximum milk production by providing

required amount of precursors for milk synthesis. In developing countries, dairy animals derive

their nutrient needs mainly from fibrous feed (Khan et al., 1999, Sarwar et al., 2002). Crop

residues especially wheat and rice straws are being recognized most important contributors to

dairy diets in developing regions of the world (Mehra et al., 2001, Man and Wiktorsson, 2001).

However, their poor nutritive value and digestibility limit intake and thus, adversely affect

animal performance.

Many agro industrial byproducts have been nutritionally evaluated and are being used as

feedstuffs for ruminant feeding (Nisa et al., 2010). To make the nutrient deficiency good, new

feed byproducts need to be added into national feed inventory after the determination of their

nutritional worth. Incorporating these feed byproducts into animal‘s diet not only reduces the

nutrient gap but it will also help in cost effective ruminant production. So it is imperative to

evaluate new agro industrial byproducts for usage as livestock feed (Nisa et al., 2010).

Enzose, derived from the enzymatic conversion of corn starch, is a byproduct of corn

milling industry which contains 85% dextrose (Sarwar et al., 2007). It can be a promising

substitute of concentrate (Khanum et al., 2007) and other expensive energy sources like corn

grains, if nutritionally evaluated. However, suggesting enzose as a potential replacement of any

energy feed ingredient needs it biological evaluation. The scientific information about the use of

enzose in animal diet as an energy source is limited. Therefore, present study was planned to

examine the dietary effects of enzose on nutrient intake, nutrient digestibility, nitrogen balance,

blood biochemistry, hormonal profile and milk production in early lactating nili-ravi buffaloes.


LXXXVIII




mean temperature ranges from 24 to 50ºC (Aheer et al., 2008), highest in June-July and lowest in

December –January.

Animals and Diets

25 early lactating Nili-Ravi buffaloes (15+5 days in milk) were randomly divided into 5


(17% CP) and isocaloric (2.82 Mcal/kg) diets were formulated. The control diet (C) had 0%

enzose and in E20, E40, E60 and E80 diets, 20, 40, 60 and 80% corn on energy equivalent was

replaced by enzose, respectively (Table 6.1). Enzose was obtained from the Rafhan Maize

Products (Pvt.) Faisalabad, Pakistan, a multinational maize processing company. Animals were

treated against all internal and external parasites and vaccinated against local diseases

(Hemorrhagic Septicemia, Foot and Mouth Disease) before the start of experiment. The

experiment lasted for 90 days including an adaptation period of 20 days.

Feeding management and data collection

Animals were housed on a concrete floor in separate pens and no mechanical means were



h) a day and animals were fed at ad libitum. Samples of feed offered and refused were collected

for analysis. Feed offered and refused were weighed to calculate DMI. Digestibility trials were

conducted for 7 days after every 30 days. Total three digestibility trials were conducted during

the experiment. The digestibility trial comprised of 7 days (3 days preliminary period and 4 days

for quantitative period) for complete collection of feces and urine. During collection period,

animals were fed 10% less feed in order to avoid refusal. During collection periods, complete

collections of urine and feces were made according to the procedure described by Williams et al.

(1984). The feces of each animal were collected daily in specially designed drum, weighed;

mixed thoroughly and 20% of it was sampled and dried at 55°C. At the end of each collection

period, dried fecal samples were composited by animal and 10% of the composited samples of

each animal were taken for analysis. Small special metal buckets fitted with a plastic pipe were

made for urine collection. This plastic pipe ended in a large container. Before collection periods,

LXXXIX

the urine excreted by an animal was measured for three days to assess its volume in 24 hours.

This was done to know the amount of 50% H2SO4 to be added to maintain urine pH at about 4.0

which minimizes the escape of urinary ammonia nitrogen (Shahzad et al., 2008a). This measured

amount of 50% H2SO4 was added into cylinders and whole day urine excreted by a buffalo was

recorded. After weighing the urine voided by each animal in 24 hour, 20% of it was sampled and

preserved at -20°C (Shahzad et al., 2008a). At the end of each collection period, the frozen urine

samples were thawed and composited by animal and 10% of the composited urine sample was

used for N analysis. Buffaloes were milked twice daily and individual milk weights were

recorded.

Laboratory Analysis

Feed and fecal samples were analyzed for DM, CP and urine samples were analyzed for

N (AOAC, 1990). The ADF was determined by using acetyletrimethyle ammonium bromide


using sodium sulfite (VanSoest et al., 1991). The analysis of milk constituent was performed on

Milko-Scan 33 to determine fat, protein, true protein, NPN, lactose and SNF.

Blood Sampling and Biochemical Analysis

Blood samples were collected six hours after the last feeding on this trial. Blood sample

(10 mL from each animal) was collected by puncturing jugular vein; 2mL was collected into

vaccutainers each containing 81µL of 15% EDTA (anticoagulant) solution, while 8mL was

collected in test tube to harvest the serum for further analysis. Plasma samples were separated

and frozen at -20°C within 60 minutes of collection. Blood samples were analyzed for plasma

urea nitrogen (PUN) using Breuer & Breuer Diagnostic kit, Germany (Bull et al., 1991) and

creatinine according to methods described by Davies et al. (2007). Serum minerals were

determined following procedures described by AOAC (1990). Hematological analyses (complete

blood count) and blood biochemistry parameters were done by Auto Analyser BST 30 using

Biometra kit.

Statistical analysis


significance, means were separated by Duncan's Multiple Range Test by using the software,

SPSS (version 17).

XC

RESULTS


The DM, CP and ADF intakes remained unchanged (p>0.05) across all diets (Table

6.2). Maximum DMI was recorded in buffaloes fed C diet followed by those fed E20, E40, E60

and E80 diets, respectively (Table 6.2). There had been a lower (p<0.05) NDF intake in animals

fed E80, E60 and C diets followed by those fed E40 and E20 diets, respectively. The DM, NDF

and ADF digestibilities were higher (p<0.05) in animals fed E80 and E60 diets followed by those

fed E40, E20 and C diets, respectively (Table 6.2).

Nitrogen balance

The PUN were higher (p<0.05) in animals fed C and E20 diets followed by those fed

E40, E60 and E80 diets, respectively (Table 6.3). The highest (p<0.05) nitrogen balance had

been observed in buffaloes fed E80 and E60 diets followed by those fed E40, E20 and C diets,

respectively. The nitrogen intake fecal N and urinary nitrogen remained unchanged (p>0.05)

across all diets. The nitrogen balance was higher (p<0.05) in buffaloes fed E80 and E60 diets

followed by those fed E40, E20 and C diets, respectively (Table 6.3).


The erythrocyte count, absolute values, white blood cell count and DLC remained

unchanged (p>0.05) across all diets. However, the eosinophil concentration was higher (p<0.05)

in animals fed E60 and E80 diets followed by those fed E60, E40, E20 and C diet, respectively.

The platelets count was higher (p<0.05) in animals fed E80, E60 and E40 diets followed by those

fed E20 and C diets, respectively (Table 6.4).

Serum Minerals

The serum mineral profile remained unaltered (p>0.05) across all diets (Table 6.5).

Blood Biochemistry

The blood urea, creatinine, ALT, A/G and BD remained unaltered (P>0.05) across all

diets. However, ALP, SGOT, total protein, albumin, globulin, BT and BI showed a higher

(p<0.05) trend in buffaloes fed enzose diets as compared to those fed C diet (Table 6.6). The

ALP concentration was higher (p<0.05) in animals fed E80, 60 and E40 diets followed by those

XCI

fed E20 and C diets, respectively. Similarly, SGOT and albumin values also followed the same

trend across all diet. However, total protein, globulin, BT and BI remained higher (p<0.05) in

animals fed E40 and E60 diets followed by those fed E20, E80, and C diets, respectively (Table

6.6).

Thyroid Hormones

The T3, T4 and their ratio remained unaltered (p>0.05) across all diets (Table 6.7).


Milk production, its fat, protein, true protein, NPN and SNF values remained unaltered

(p>0.05) across all diets. However, 4% FCM and lactose values remained higher in animals fed

E80 and E60 diets followed by those fed E40, E20 and C diets, respectively (Table 6.8).

DISCUSSION


The DMI, CP and ADF intake by lactating buffaloes fed diets containing enzose

remained unchanged across all diets. Similar findings were also reported by Yadave and Virk

(1994), Sarwar et al. (1994), Dass et al. (2001) and Mehra et al. (2001). This lack of difference

in nutrient intake may be because of similarity among dietary nutrients. There are many factors,

including physical fill (Allen, 1997; Mertens, 1994) and many metabolic-feeding factors (Illius

and Jessop, 1996), which are responsible to control DMI in ruminants (Forbes, 1996),. Feeds low

in digestibility reduced DMI because of their slow passage rate through the digestive tract. The

reticulo-rumen and possibly the abomasum stretch and touch receptors in their walls affecting

DMI negatively as the weight and volume of digesta accumulate (Allen, 1997). Thus, each factor

might operate under some conditions, but it is most likely the additive effect of several stimuli

that regulate DMI (Forbes, 1996). Nutrients and their ingestion are the important constituent of

daily ration of ruminants (Mukhtar et al., 2010: Khalid et al., 2011). The concept of nutrients

rich diets with varying ingredients levels has linear relationship on feed intake and their ingestion

(Negesse et al., 2001).

The increased DM, NDF and ADF digestibility by buffaloes fed diets containing enzose

may be because of its rapidly fermentable nature. The replacement of enzose with corn grains

was thought to ferment rapidly in the rumen that might have ensured sufficient availability of

XCII

keto acids (i.e. carbon skeleton), a vital requisite for microbial multiplication which might have

enhanced rumen microbial enzyme production leading to increased nutrient digestibilities and

intake (Nisa et al., 2004a; Nisa et al., 2004b; Sarwar et al., 2004; Khan et al., 2004; Mukhtar et

al., 2010; Khalid et al., 2011). This implies that dietary cellulose and hemicellulose get

extensively fermented, enhancing NDF and ADF digestibility in the present study. The improved

NDF and ADF digestibility can also be attributed to improved cellulytic activities in rumen.

Khan et al. (2004) reported that the increased NDF digestibility could be because of its increased

rate of degradation and shorter lag time of diets containing enzose. Improved fiber digestion was

due to improved cellulose digestion by inhibiting the growth of lactate producing bacteria

(Russell and Stroble, 1989; Khan et al., 2004, Khanum et al., 2010; Shahzad et al., 2010). This

finding was also supported by Sarwar et al. (1991), Mukhtar et al. (2010) and Khalid et al.

(2011) who reported that different feeding regimens have positive effect on nutrient digestibility

in ruminants.

Nitrogen balance

The highest nitrogen balance in buffaloes fed E60 and E80 diets is an indication of better

nitrogen utilization. The PUN was lower (P<0.05) in buffaloes fed diets with varying levels of

enzose. Similarly, fecal N and urinary nitrogen also remained unaltered in animals across all

diets. The PUN is a reliable indicator of protein status of animals (Sykes, 1978) and it reflects

ruminal NH3-N concentration because the liver removes 70 to 80% portal absorption of urea-N

secreted by the liver during abnormal hepatic function (Huntington, 1990). Some researchers

have defined PUN concentration as bio-indicator of renal tubular function, CP intake and CP

metabolism in animals (Oltner and Wiktorsson., 1983; Roseler et al., 1993). Higher PUN was

related to ammonia absorption from rumen and deamination of amino acids (AA) and increased

N retention (Adams et al., 1981). The slower release of fiber bound N was synchronized with

fiber fermentation and thus utilized by the rumen micro-flora (Nisa et al., 2004). Slow release of

NH3-N resulted in less NH3 absorption through the ruminal walls that consequently lowered the

plasma urea N and urinary N loss and thus higher N retention in buffaloes (Khan et al., 2004).

The higher values of nitrogen balance in buffaloes fed E80 and E60 diets in current study were

supported by Mukhtar et al. (2010) who reported that different feeding regimens have significant

effect on nitrogen balance in ruminants. Similarly Mukhtar et al. (2010) also reported that the

http://jds.fass.org/cgi/content/full/90/12/5714#HUNTINGTON-1990

XCIII

different feeding regimens have significant effect on nitrogen balance in small ruminants.

Findings of the present study was in contrast to the findings of Khalid et al. (2011) who reported

that different feeding regimens has no any effect on PUN.


A non-significant effect had been observed on hematological parameters in animals

across all diets. Unaltered hematological values in animals fed enzose supplemented diets is

supported by Nelson and Watkins (1967) who reported that blood hemoglobin and hematocrit

were unaffected by different feeding regimens. The same observation had been noted by

Mukthar et al. (2010) and Khalid et al. (2011). Blood profile is an important indicator of animal

health (Cheesbrough, 1991). In biological system, monocytes defend the tissues against

microbial agents (Scholm et al., 1975). Packed cell volume of blood is useful in detecting

dehydration or normocytic normochromic anemia that may be indicative of certain toxicities

(Scholm et al., 1975). Lymphocytes play an important role in the formation of cellular immunity

and defensive system of the body (Baker and Silver, 1985). These cells proliferate and their

interferon production increase with oral probiotics supplementation. The DLC values remained

unchanged across all diets. The findings of present study were supported by Ghulf (2006) who

observed non-significant increase in neutrophils, eosinophils, basophils, monocytes and

lymphocytes. However experimental value fall within normal range value reported by Merk

Veterinary Manul (2005). The increased platelets in animals fed diets containing enzose was

concordant to findings of Aboderin and Oyetayo, (2006) who reported that the increasing levels

of different energy sources have significant effect on platelets counts. On the other hand,

platelets are important circulating constituents of the blood and have important functions i.e.

blood clotting and hemostasis (Sunitha and Munirathnam, 2008). Platelets also release natural

growth promoters’ i.e. platelet-derived growth factor, transforming growth factor-β that helps

repair and regeneration of connective tissues. In conclusion, hematologic picture remained

unaffected by various enzose levels.

Serum Minerals

Serum minerals are involved in maintaining fluid osmotic pressure, water balance,

nervous and muscular functions and acid base balance (Juniper et al., 2009). The availability and

retention of minerals are influenced by feed supplementation (Mukhtar et al., 2010; Khalid et al.,

2011). Unaltered effect of enzose on serum minerals was supported by Galip, (2006) and

XCIV

Mateova et al. (2009) who reported that different feeding regimens had no influence on serum

Ca concentration. In relation to thyroid, many mineral like Ca concentration may be influenced

by parathyroid hormone (Brown, 1991) which is responsible to synthesize 1, 25 di-

hydroxycholecalciferol in kidneys that is involved in Ca absorption from the intestine (Hurwitz,

1996). In contrary to present findings, Panda et al (2001) reported that feeding regimens had

significant effect on serum minerals.

Blood Biochemistry


of protein in the rumen and the rate of utilization of NH3 for bacterial protein synthesis. An

increase in serum urea level may reflect an accelerated rate of protein catabolism rather than a

decrease in urinary excretion (Kaneko, 1980). The serum urea level also increases in renal


1985).

An increase in serum creatinine levels is generally seen in degenerative muscle diseases

(Prassee, 1986). The quantity of creatinine formed each day depends upon the creatinine content

of the body, which in turn depends upon the dietary intake, inhibiting the endogenous synthesis

rate and the muscle mass (Walker, 1961). Elevated creatinine levels in the serum/plasma are also

associated with various renal diseases. Creatinine is formed during the metabolism of creatinine

in the muscle and its increased concentrations in the serum are the indicator of a decreased

glomerular filtration rate. Serum creatinine concentration is a quantitative marker of renal

function (Butani et al., 2002). No change in serum creatinine due to different is supported by

Street (2001) who observed no effect of dietary protein source on creatinine. Unaltered serum

creatinine is in agreement with the results of Antunovic et al. (2006) and Galip, (2006). The

increasing (P>0.05) trend in creatinine concentration in buffaloes across all diets in the present

study is supported by the findings of Mukhtar et al. (2010) and Khalid et al. (2011).

Among various tissues and organs, a higher ALP activity occurs in kidneys and

intestines, and is moderate in the liver, lungs, bone, placenta and leukocytes (Cornelius, 1980).

However, the use of ALP as a diagnostic tool for detecting tissue damage is limited, especially in

young growing animals, where bone can be a very significant source of ALP (Evans, 1988). The

ALP plays an important role in the regulation of cell division and growth (Swarup, 1981) and its

activity attains higher levels in the serum of growing animals. The result of the present study

XCV

revealed that there had been higher ALP values in animals fed enzose diets which could be

attributed to the enhanced metabolic activities. In contrast to this, Ahuja et al. (1977) did not find

any change in serum ALP activity in buffalo bulls.

Both SGOT and ALT are cytoplasmic and mitochondrial enzymes and are distributed in

all body tissues (Evans, 1988). A rise in SGOT activities occurs in acute and occasionally in

chronic liver disorders in cattle, but remarkably higher values has been recorded in muscle

damage (Petrie, 1987). The SGOT catalyzes amino groups and ketone between α amino acid and

α ketone acid. This enzyme is usually produced in heart, body muscle, brain and lungs, less of it

is found in liver (Pratt and Kaplan, 2000; Rochling, 2001; Murray et al., 2003). The findings of

the present study revealed that there had been higher values of SGOT in animals fed enzose diets

which could be attributed to the better effect of normal metabolic process. Enzose might have

enhanced metabolic process which improved productive performance of buffaloes. However, the

ALT remained unchanged in buffaloes fed diets containing enzose.






of buffaloes fed diets containing enzose. In conclusion, these liver function tests can be reliable

indicators of hepatic functionality in buffaloes which are generally interpreted in conjunction

with clinical symptoms.

Serum albumin is synthesized by the liver and is catabolized by a wide variety of tissues.

Serum albumin supplies readily available pool of amino acids to meet tissue needs depending

upon the nutritional status. Its synthesis is diminished during fasting, malnutrition, hormonal

imbalances and poor condition of the liver and the serum globulins, mainly the α and β globulins

are increased in acute inflammatory conditions such as acute hepatitis and glomerulonephritis

and the γ globulins are mainly related with the immuno-status of animal (Jain, 1986). The higher

values of serum albumin and globulin in buffaloes fed diets containing enzose elucidate its

positive impact on physiological health of animals. The similar findings had been noticed by

other workers (Ahuja et al., 1977; Daas et al., 2001; Nair et al., 2002 and Naik et al., 2004).

XCVI

Rosenberger (1979) stressed that total bilirubin content of bovine serum was an important

liver function test. The higher values of bilirubin and bilirubin indirect in buffaloes across all

diets demonstrated that enzose had a positive impact on overall health status of animals.

Thyroid hormones

Blood thyroid hormones are considered to be a good indicator of nutritional status of

animals (Forshthe, 1995). Thyroxin plays a key role in the partitioning of nutrients to different

body compartments (Beard et al., 1998). The thyroid hormones, T3 and T4 act on different target

tissues and stimulate the oxygen utilization and also increased the heat production in every cell

of the body. These hormones increase the basal metabolic rate, to make more glucose available

to cells, stimulate protein synthesis, increase the lipid metabolism (Todini et al, 2007) and also

speed up the diastolic relaxation of heart (Kahaly and Dillmann, 2005). The T3 is physiologically

more active than T4, and provides a better indication of the metabolic status of the animal

(Shukla et al., 1994; McDonald and Pineda, 1989). Thus the serum T3 and T4 concentrations

seem to be significantly related to the growth and age of the animal (Guyton and Hall, 2000).

The mean values of serum T3 and T4 found in this experiment were within the normal

physiological range. Unaltered effect of enzose with similar nutrients profile shows that enzose

does not have any detrimental effects on metabolic hormones. Cree and Schalch (1985) reported

that T4 and T3 concentration were higher in wheat gluten diets than casein protein. Similar

findings have also observed by Mukhtar et al. (2010) and Khalid et al. (2011).


Varying enzose levels had non-significant effect on many milk components. Such

findings were previously described by other workers (Sutton, 1989; Cant et al., 1991; Khanum,

et al., 2010; Sarwar et al., 1992). Increasing levels of enzose in the diets might have provided a

better synchronization of nutrients at cellular level that helps synthesize more milk. The higher

milk production by buffaloes may also be attributed to increased digestible NDF intake.

Milk urea nitrogen (MUN) is an excellent indicator of urea nitrogen status in dairy cows

(Ahlam et al., 2010; Roseler et al., 1993). The MUN is the major single contributor to milk

NPN. Milk urea is derived primarily from blood urea which is produced from excess ruminal

ammonia and amino acids catabolism in the liver (De Peters and Ferguson, 1992). In the

mammary gland, urea diffuses into and out of the mammary gland cells, equilibrating with urea

XCVII

in the blood. Because of this process, milk urea nitrogen (MUN) equilibrates with and is

proportional to blood true protein and NPN, as percentage of milk protein did not show any

treatment effect. Percent milk fat, SNF and total solid remained unchanged across all treatments.

Conclusion

In conclusion, buffaloes fed diets containing enzose had higher digestibility, better

nitrogen balance, produced more milk and lower PUN than those fed C diet.


enzose fed to early lactating Nili Ravi buffaloes


C E20 E40 E60 E80

Wheat Straw 30.0 30.0 30.0 30.0 30.0

Corn Grains 24.0 18.0 12.0 6.0 0.0

Enzose 0.0 6.0 12.0 18.0 24.0

XCVIII

Urea 2.0 2.0 2.0 2.0 2.0

Canola Meal 5.0 5.5 5.5 5.5 8.0

Corn Glutten 30% 12.0 13.0 13.0 13.0 10.5

Rice Polishings 14.0 13.0 13.0 13.0 11.0

Maize Bran 10.5 10.0 10.0 10.0 12.0

Maize Oil 1.0 1.0 1.0 1.0 1.0

NaHCO3 0.5 0.5 0.5 0.5 0.5

Salt 1.0 1.0 1.0 1.0 1.0


Dry Matter 90.0 89.5 89.1 88.6 88.0

Crude Protein 17.1 17.15 17.1 17.1 17.15



Non Structural

Carbohydrates 33.0 35.0 35.0 35.0 35.0


ME (Mcal/kg) 2.82 2.82 2.82 2.82 2.82

1, C, E40, E60 and E80 diets contained enzose as replacement of corn grains at the rate of 0, 20, 40, 60 and 80%


Table 6.2 Effect of varying levels of enzose when replaced with corn grains on nutrient

intake and their digestibility in early lactating Nili Ravi buffaloes

Parameters Diets1

C E 20 E 40 E 60 E 80 SE


Dry matter 16.91 16.89 16.87 16.81 16.80 0.025

Crude protein 2.87 2.87 2.88 2.89 2.89 0.22

XCIX

Neutral detergent

fiber

8.31a 8.17bc 8.26b 8.0bc 7.72c 0.061

Acid detergent

fiber

4.91 4.85 4.76 4.7 4.68 0.032

Nutrient digestibilities (%)

Dry matter 62.4c 65.3bc 66.1b 67.3b 68.7a 0.606

Crude protein 78.9 77.5 77.2 77.3 78.0 0.275

Neutral detergent

fiber

56c 58bc 60ab 60.2b 62.3a 0.612

Acid detergent

fiber

47d 48cd 50c 53b 57a 0.985


1C, E20, E40, E60 and E80 diets contained enzose as replacement of corn grains at the rate of 0, 20, 40, 60 and


SE Standard Error

Table 6.3 Effect of varying levels of enzose when replaced with corn grains on nitrogen

balance in early lactating Nili Ravi buffaloes

Parameters

(g/day)

Diets1

C E20 E40 E60 E80 SE

Plasma Urea

Nitrogen, mg/dL

16.7a 15.9ab 14.9abc 14.1c 13.9c 0.406

Nitrogen Intake 459.2 459.2 459.20 462.4 462.4 1.115

Fecal Nitrogen 401.6 401.6 400.0 400.0 398.4 0.282

C

Urinary Nitrogen 45.92 45.92 45.92 46.24 46.24 2.018

Nitrogen Balance 11.6c 11.68c 13.28b 16.16a 17.76a 2.756




SE Standard Error

Table 6.4 Effect of varying levels of enzose when replaced with corn grains on blood

hematological characteristics in early lactating Nili Ravi buffaloes


C E20 E40 E60 E80 SE

Erythrocytes

Hemoglobin (g/dl) 11.3 11.2 11.4 11.6 11.6 0.048

Hematocrit (%) 39.7 39.0 39.1 39.5 39.6 0.075

CI

Absolute Values

Total RBC count

(m/ul)

6.8 6.8 6.9 7.1 7.2 0.176

MCV (fl) 65 65.2 65.5 66.9 68.7 1.375

MCH (Pg) 20.5 20.8 21.2 21.5 21.5 0.302

MCHC (g/dl) 33.8 33.0 34.4 33.1 34.3 0.76

White Blood Cells (k/ul)

Total WBC Count 8.8 8.6 8.7 8.8 8.7 0.03

DLC (%)

Neutrophiles 75 74 75 74 76 0.28

Lymphocytes 50 55 55 60 65 1.666

Monocytes 02 02 03 03 03 0.163

Eosinophile 03d 05c 06bc 07b 8a 0.480

Thrombocyte (k/ul)

Platelets Count 170b 170b 175ab 180ab 185a 1.838

Means within row bearing different superscripts differ significantly (p<0.05) 1C, E20, E40, E60 and E80 diets contained enzose as replacement of corn grains at the rate of 0, 20, 40, 60 and


RBC-Red Blood Cell, WBC-While Blood Cell, DLC-Differential Leukocyte Count, MCV-Mean Corpuscular

Hemoglobin, MCHC- Mean Corpuscular Hemoglobin Concentration

SE Standard Error


mineral profile in early lactating Nili Ravi buffaloes

Parameter Diets1

C E20 E40 E60 E80 SE

Na (mEq/L) 135 135 137 139 139 1.191

K (mEq/L) 5.3 5.9 5.5 5.6 5.8 0.064

Ca (mg/dL) 9.8 9.9 9.8 9.8 9.9 0.023

CII

P (mg/dL) 5.5 5.55 5.6 5.5 5.55 0.024

Cl (mEq/L) 107 105 108 108 110 0.486

HCO3 (mEq/L) 25 27 27 26 27 0.363


80% on the basis of energy supply by corn grains, respectively. SE Standard Error


biochemistry in early lactating Nili Ravi buffaloes

Parameter Diets1

C E20 E40 E60 E80 SE

Urea (mg/dL) 56 58 65 75 80 3.174

Creatinine (mg/dL) 1.4 1.4 1.45 1.55 1.6 0.029

Enzymes (U/L)

ALT 50 51 50 52 50 2.81

CIII

ALP 120b 135b 165a 170a 176a 6.22

SGOT 135c 146bc 169b 165ab 178a 4.641

Blood Protein (g/dL)

Total Protein 6.9c 7.7a 7.8a 7.9a 7.2b 0.104

Albumin 2.3b 2.4b 2.4b 2.5b 2.8a 0.05

Globulin 4.6b 5.5a 5.6a 5.5a 5.4a 0.099

A/G 0.5 0.4 0.5 0.6 0.6 0.026

Bilirubin (mg/dL)

B.T 0.7ab 0.6ab 0.8a 0.7ab 0.5b 0.033

B.D 0.3 0.2 0.3 0.3 0.2 0.016

B.I 0.4ab 0.4ab 0.5a 0.4ab 0.3b 0.021



ALT- alanine aminotransferase, ALP- alkaline phosphatase, SGOT- serum glutamic oxaloacetic transaminase, B.T-

bilirubin total, B.D- bilirubin direct, B.I- bilirubin indirect

SE Standard Error

Table 6.7 Effect of varying levels of enzose when replaced with corn grains on thyroid

hormone profile in early lactating Nili Ravi buffaloes

Parameter (nmol/L) Diets1

C E20 E40 E60 E80 SE

T3 1.75 1.8 1.8 1.8 1.8 0.019

T4 41.45 41.43 41.71 41.52 41.57 0.355

T3/T4 23.1 23.85 23.54 23.27 23.98 0.235


CIV



T3- triiodothyronine, T4- thyroxine

SE Standard Error

Table 6.8 Effect of varying levels of enzose when replaced with corn grains on weight gain,

milk quantity and milk composition in early lactating Nili Ravi buffaloes

Parameter Diets1

C E20 E40 E60 E80 SE

Quantity (kg/d) 7.4 7.9 8.2 8.5 9.2 0.252

4% FCM 12.0c 13.43bc 14.15b 15.3b 17.25a 0.521

Milk Constituents

(%)

CV

Fat 6.5 6.8 6.9 7.2 7.5 0.215

Protein 3.7 3.7 3.7 3.8 3.8 0.055

True Protein 3.58 3.57 3.6 3.68 3.65 0.053

Non-Protein Nitrogen 0.22 0.23 0.2 0.22 0.23 0.004

Lactose 5.55b 5.6b 5.8ab 5.9a 5.9a 0.045

SNF 10.2 10.3 10.3 10.35 10.5 0.034



SNF- Solid Not Fat, FCM-Fat Corrected Milk

SE Standard Error

Chapter 7 SUMMARY

Four independent experiments were conducted to examine the influence of varying levels

of corn steep liquor (CSL) and enzose on feed intake, growth performance and carcass

characteristics of growing nili-ravi male buffalo calves and blood biochemistry, milk yield and

its composition in early lactating nili-ravi buffaloes.

CVI

In first experiment, fifty male buffalo calves of 9 month old were randomly divided into

five groups, 10 animals in each group. Five isonitogenous (16% CP) and isocaloric (2.6 Mcal/kg)

diets were formulated. The control diet (C) had 0% CSL and in CSL20, CSL40, CSL60 and

CSL80 diets, 20, 40, 60 and 80% urea on nitrogen equivalent was replaced by CSL, respectively.

Animals fed CSL40 diets ate highest DM (3.33 kg daily) and was the lowest (3.16 daily) by

those fed CSL40 diets. The NDF and ADF digestibility was higher (P<.05) in animals fed diets

containing CSL than those fed diet containing 0% CSL. However, DM and CP digestibility

remained unaltered (P>0.05) across all diets. Calves fed CSL40 gained more (P<0.05) weight

(757 g/day) than those fed CSL80 diet (637 g/day). Feed cost per Kg weight gained was higher

(PKR 80.79) in calves fed CSL0 diet; however feed conversion ratio was better in calves fed

CSL40 diet(4.89) than those fed CSL20, CSL60 and CSL80 diets. The red blood cell count,

white blood cells, packed cell volume and hemoglobin values were also same across all diets. Pre

slaughter weight of animals fed CSL40 diet was the highest (141.5 kg) and was the lowest (130

kg) in those fed CSL80 diet. Warm carcass weight was higher (P<0.05) in animals fed CSL40

(65.8 kg) diet followed by those fed CSL60, CSL80, CSL20 and C diets. Dressing percentage,

skin, feet weight, and weight of all body organs remained unaltered across all diets. Similarly

primal cuts, ash, Na, K and Ca remained unchanged across all diets.

In second experiment, thirty five male buffalo calves of one year old were randomly

divided into five groups, 7 animals in each group, using Randomized Complete Block Design.

Five isonitogenous (17.5% CP) and isocaloric (2.6 Mcal/kg) diets were formulated. The control

diet (C) had 0% enzose and in E20, E40, E60 and E80 diets, 20, 40, 60 and 80% corn on energy

equivalent was replaced by enzose, respectively. Animals fed control diet ate highest (7.65

kg/day) DM and was the lowest (7.39 kg/day) in animals fed E80 diets. The same trend of intake

had also been observed for CP, NDF and ADF. The NDF and ADF digestibility was higher in

animals fed diets containing enzose than those fed C diet. The DM and CP digestibility remained

unaltered (p>0.05) across all diets. However, there had been significant different (p<0.05) in

NDF and ADF digestibility. The highest NDF digestibility (61.8%) was observed in calves fed

E40 diet whereas the lowest NDF digestibility (59%) was noticed in calves fed control diet. The

same trend had also been observed in ADF digestibility. Calves fed control gained more

(P<0.05) weight (801 g/day) than those fed E80 diet (770 g/day). Feed cost per Kg weight gained

was higher in calves fed E40 (PKR 109.32) diet and lowest in calves fed E80 (PKR 79.62) diet;

CVII

however feed conversion ratio was better in calves fed diets containing 80% enzose (6.08) than

those fed other diets. The red blood cells, white blood cells, packed cell volume, hemoglobin and

mineral profile of meat by claves fed enzose diets remained unchanged (p>0.05) across all diets.

Pre-slaughter weights had been non-significant (p>0.05) across all treatment groups. A

significant difference in warm carcass weight was (P<0.05) observed. The highest value (91.8

kg) was noticed in calves fed E80 diets and the lowest value (88.8 kg) was found in those fed

E40 diet. Dressing percentage, skin, feet weight, all body organs, primal cuts, lean, fat and bone

proportion remained unchanged (p>0.05) across all diets.

In third experiment, twenty five early lactating buffaloes were randomly divided into

five groups, 5 animals in each group, using Randomized Complete Block Design. Five

isonitogenous (17% CP) and isocaloric (2.82 Mcal/kg) diets were formulated. The control diet

(C) had 0% CSL and in CSL20, CSL40, CSL60 and CSL80 diets, 20, 40, 60 and 80% urea on

nitrogen equivalent was replaced by CSL, respectively. The DM, CP, NDF and ADF intakes

remained unchanged (P>0.05) in buffaloes fed CSL diets. The DM and NDF digestibility were

higher (P<.05) in animals fed diets containing CSL than those fed C diet. However, CP and ADF

digestibility remained unaltered (P>0.05) across all diets. PUN and nitrogen balance showed a

significant (P<0.05) difference in buffaloes fed CSL diets whereas; nitrogen intake, fecal

nitrogen and urinary nitrogen values remained unchanged across all diets. The blood mineral

profile remained (P>0.05) unaffected across all diets. The blood urea, ALT, A/G, BD and BI

values remained unchanged (P>0.05) across all diets. The creatinine, ALP, SGOT, total protein,

albumin, globulin and BT values showed a significant (p<0.05) difference in buffaloes fed CSL

diet. The thyroid hormones, T3, T4 and T3:T4 remained unchanged (P>0.05) across all diets. Milk

production, its fat, protein, true protein, NPN and SNF values remained unaltered across all diets.

4% FCM and lactose values showed a significant difference in buffaloes fed CSL diets.

In fourth experiment, twenty five early lactating buffaloes were randomly divided into

five groups, 5 animals in each group, using Randomized Complete Block Design. Five

isonitogenous (17% CP) and isocaloric (2.82 Mcal/kg) diets were formulated. The control diet

(C) had 0% enzose and in E20, E40, E60 and E80 diets, 20, 40, 60 and 80% corn on energy

equivalent was replaced by enzose, respectively. The DM, CP and ADF intake remained

unchanged (P>0.05) in buffaloes fed enzose diets. However, the NDF intake was significantly

(P<.05) different across all diets. The DM, ADF and NDF digestibilities were higher (P<.05) in

CVIII

animals fed enzose diets than those fed C diet. However, CP digestibility remained unaltered

(P>0.05) across all diets. PUN and nitrogen balance showed a significant (P<0.05) difference in

buffaloes fed enzose diets whereas; nitrogen intake, fecal nitrogen and urinary nitrogen values

remained unchanged across all diets. The blood mineral profile remained (P>0.05) unaffected

across all diets. The blood urea, creatinine, ALT, A/G and BD values remained unaltered

(P>0.05) across all diets. The ALP, SGOT, total protein, albumin, globulin, BT and BI value

showed a significant (p<0.05) difference in buffaloes fed enzose diets. The thyroid hormones, T3,

T4 and T3:T4 remained unchanged (P>0.05) across all diets. Milk production, its fat, protein, TP,

NPN and SNF values remained unaltered across all diets. 4% FCM and lactose values showed a

significant difference in buffaloes fed enzose diets. In conclusion, increased nutrient ingestion,

utilization and weight gain reflect the suitability and potential of enzose and CSL as an

economical energy and protein sources when used to replace corn grains and urea, respectively.

Similarly, buffaloes fed enzose and CSL supplemented diets had higher nutrient intake and

digestibility. The animals had better nitrogen balance, blood biochemistry, hormonal profile and

they produced milk with better quantity and quality when fed enzose and CSL in their diets.

In conclusion, male buffalo calves fed CSL40 diet gained more weight and were cost-

effective. Likewise, increased nutrient ingestion, utilization and weight gain reflect the suitability

and potential of enzose as an economical energy source when used to replace corn grains upto

80% of the diet of growing male buffalo calves. In case of early lactating buffaloes, animals fed

diets containing CSL ate more DMI, had higher digestibility, better nitrogen balance, produced

more milk and lower PUN than those fed C diet. Similarly buffaloes fed diets containing enzose

had higher digestibility, better nitrogen balance, produced more milk and lower PUN than those

fed C diet. These results reflect the nutritive potential of enzose and corn steep liquor as

economical energy and nitrogen sources when used to replace corn grains and urea, respectively

in the diets of growing male buffalo calves and early lactating buffaloes.

CIX

LITERATURE CITED

Adugna, T. and F. Sundstol. 2000. Supplementation of graded levels of Desmidian intortum hay

to sheep feeding on maize stover harvested at three stages of maturity 2. Rumen

fermentation and nitrogen metabolism. Animal Feed Sci. Technol. 87:215-229.

Aguilera, J. F. 1989. Use of Agro-industiral by-products in the feeding of ruminants. Revista

Argentina de production animal. 9:253-267.

CX

Ahmad, I., K. Javed, R. H. Mirza, A. Sattar and F. Ahmad. 2004. Effect of feeding sunflower

meal as a substitute of cotton seed cakes on growth and age at maturity in Holstein

Friesian heifers. Pakistan Vet. J. 24:95-97.

Akram, M. 1990. Pakistan: Animal Feed Resources in Asia and Pacific. Asian Productivity

Organization, Tokyo.

Ali, C. S., M. Sarwar, R. H. Siddiqi, R. F. Husain, T. Khaliq, S. U. R. Chaudhary and A. R.

Barque. 1993. Effect of urea treatment of wheat straw on disappearance and rate of

passage through reticulo-rumen of buffalo. Pakistan Vet. J. 13:74.

Ali, I., R. Fairbairn, B. E. Baker, L. E. Philips and H. Garino. 1983. Effects of anhydrous

ammonia on fermentation of chopped, high-moisture ear corn. J. Dairy Sci. 66:2343.

Allen, M. S. 1996. Physical constraints on voluntary intake of forage by ruminants. J. Anim. Sci.

74:3063-3075.

Allen, M. S. 1997. Relationship between fermentation acid production in the rumen and the

requirement for physical effective fiber. J. Dairy Sci. 80:1447-1462.

AOAC, 1995. Official methods of analysis (16th ed.). Association of Official Analysis Chemists

International. Arlington, Virginia, USA.

AOAC, Association of Official Analytical Chemists. 2002. Official Method of Analysis.15th ed.

Arlington.

Armstrong, J. D. and J. W. Spears. 1988. Intravenous administration of ionophores in ruminants:

Effects on metabolism independent of the rumen. J. Anim. Sci. 66:1807.

Atti, N., H. Rouissi and M. Mahouachi. 2004. The effect of dietary protein level on growth,

carcass and meat composition of male goat kids in Tunisia. Small Rumin. Res. 54:89-

97.

Baile, C. A. and J. M. Forbes. 1974. Control of feed intake and regulation of energy balance in

ruminants. Physiol. Rev. 54:160.

Barry, T. N., D. I. Menna, M. E. Webb and P. R. Parle. 1980. Some observations, aerobic

deterioration in untreated silages and in silages made with formaldehyde containing

additives. J. Sci. Food Agri. 31:133.

CXI

Baumann, T.A., G. P. Lardy, J. S. Caton and V. L. Anderson. 2004. Effect of energy source and

ruminally degradable protein addition on performance of lactating beef cows and

digestion characteristics of steers. J. Anim. Sci. 82:2667-2678.

Bednarek, D., M. Kondracki and S. Cakla. 1996. Investigation into the influence of selenium

and vitamin E on red and white blood pictures, on concentration of several minerals and

microelements in blood serum, and on immunological parameters in calves. Deut.

Tierarztl. Wochenschr. 103:457-459.

Bellof, G., E. Most and J. Pallauf. 2006. Concentration of Ca, P, Mg, Na and K in muscle, fat

and bone tissue of lambs of the breed German Merino Landsheep in the course of

growing period. J. A. Phys. A. Nutr. 90:385-393.

Benerjee, G. C. 1993. Animal Husbandry. Oxford and IBH Publishing Co. Pvt. Ltd. New Delhi.

Benjamin, M. M. 1978. Outline of Veterinary Clinical Pathology. 3rd ed. The Iowa State

University Press, Ames, 351p.

Bergen, W. G., T. M. Byrem and R. J. Grant. 1991. Ensiling characteristics of whole crop small

grains harvested at milk and dough stages. J. Anim. Sci. 69:176.

Berthiaume, R., I. Mandell, L. Faucitano and C. Lafreniere. 2006. Comparison of alternative

beef production systems based on forage finishing or grain-forage diets or without

growth promotants: I. Feedlot performance, carcass quality and production costs. J.

Anim. Sci. 84:2168-2177.

Bhannasiri, Tim., R. Bogart and H. Krueger. 1961. Hemoglobin and blood cells of growing beef

cattle. J. Animal Sci. 20:18.

Bhatti, M. B. and S. Khan. 1996. Fodder Production in Pakistan. FAO, PARC, Islamabad.

Bilal, M. Q., M. Abdullah and M. Lateef. 2001. Effect of varying levels of nitrogen application

and stage of maturity on the digestibility of Mott grass. J. Anim. Plant Sci. 11:62.

Bilal, M. Q., M. Abdullah and M. Lateef. 2001b. Effect of Mott dwarf elephant grass

(Pennisetum purpureum) silage on dry matter intake, milk production, digestibility and

rumen characteristics in Nili-Ravi buffaloes. In: Proc. 54th Annual reciprocal meat

conference (Vol. II). Indianapolis, Indiana, July 24-28, 2001.

Borhami, B. E. A., F. Sundstol and T. H. Garmo. 1982. Studies on ammonia treated straw. II

fixation of ammonia in treated straw by spraying with acids. Anim. Feed Sci. Technol.

7:53.

CXII

Bowman, J. G. P., C. W. Hunt, M. S. Kerley and J. A. Paterson. 1991. Effects of grass maturity

and legume substitution on large particle size reduction and small particle flow from the

rumen of cattle. J. Anim. Sci. 69:369.

Bragg, D. S., M. R. Murphy and C. L. Davis. 1986. Effect of source of carbohydrate and

frequency of feeding on rumen parameters in dairy steers. J. Dairy Sci. 69:392-402.

Britt, D. G. and J. T. Huber. 1975. Fungal growth during fermentation and re-fermentation of

non-protein nitrogen treated corn silage. J. Dairy Sci. 58:1666.

Broderick, G. A., N. D. Luchini, S. M. Reynal, G. A. Varga and V. A. Ishler. 2008. Effect on

production of replacing dietary starch with sucrose in lactating dairy cows. J. Dairy Sci.

91:4801-4810.

Broderick, G. A., W. M. Craig and D. B. Ricker. 1993. Urea versus true protein as supplement

for lactating dairy cows fed grown plus mixture of alfalfa and corn silages. J. Dairy Sci.

76:2266.

Brown, W.F. and D. D. Johnson. 1991. Effects of energy and protein supplementation of

ammoniated tropical grass hay on the growth and carcass characteristics of cull cows. J.

Anim. Sci. 69:348-357.

Cameron, M. R., T. H. Klumeyer, G. L. Lynch and J. H. Clark. 1991. Effect of urea and starch

on rumen fermentation nutrient passage to the duodenum, and performance of cows. J.

Dairy Sci. 74:1321.

Campbell, T. C., J. K. Loosli, R. G. Warner and F. Tosaki. 1963. Utilization of biuret by

ruminants. J. Anim. Sci. 22:136.

Campbell, C. P. and J. G. B. Smith. 1991. Effect of alfalfa grass silage dry matter content on

ruminal digestion and milk production in lactating dairy cow. Canadian J. Anim. Sci.

71: 457.

Chamberlain, D. G., S. Robertson and J. J. Choung. 1993. Sugars versus starch as supplements

to grass silage: effects on ruminal fermentation and the supply of microbial protein to

the small intestine, estimated from the urinary excretion of purine derivatives, in sheep.

J. Sci. Food Agric. 63:189-194.

Chamberlain, D. G. and S. Robertson. 1992. The effects of the addition of various enzyme

mixtures on the fermentation of perennial rye grass silage and on its nutritional value

for milk production in dairy cows. Anim. Feed Sci. Technol. 37:257.

CXIII

Changula, P., A. Mesang and S. Pongprayoon. 2010. Effects of dietary inclusion of palm kernel

cake on nutrient utilization, rumen fermentation characteristics and microbial

populations of goats fed Paspalum plicatulum hay-based diet. Songklanakarin J. Sci.

Technol. 32:527-536.

Chestnutt, D. M. B. 1994. Effect of lamb growth rate and growth pattern on carcass fat levels.

Anim. Prod. 58:77-85.

Clevenger, T.E., V. Singh, R. L. Belyea, D. B. Johnston, M. E. Tumbleson and K. D. Rausch.

Year. Element concentrations in dry grind corn processing streams. In: Proc. Corn Util.

Technol. Conf. (Tumbleson, M.E., ed.) (Abstr. no. 24). NCGA, St. Louis, MO.

Comerford, J. W., R. B. House, H. W. Harpster, W. R. Henning and J. B. Cooper. 1992. Effects

of forage and protein source on feedlot performance and carcass traits of Holstein and

crossbred beef steers. J. Anim. Sci. 70:1022-1031.

Crouse, J. D., R. A. Field, J. L. Chant, C. L. Ferrell, G. M. Smith and V. L. Harrison. 1978.

Production, carcass and palatability characteristics of stress produced by different

management systems. J. Anim. Sci. 46:333-340.

Crowder, L. V. 1988. Fodder Crop Research in Pakistan. A Review, PARC/USAID/MART-

Winrock, USA.

Cruz, C. R. D., M. J. Brouk and D. J. Schingoethe. 2005. Lactational response of cows fed

Ccondensed corn distillers soluble. J. Dairy Sci. 88:4000-4006.

Cushanhan, A. and F. J. Gordon. 1995. The effects of grass preservation on intake, apparent

digestibility and rumen degradation characteristics. J. Anim. Sci. 60:429.

Cushanhan, A., C. S. Mayne and E. F. Unsworth. 1995. Effect of ensilage of grass on

performance and nutrient utilization by dietary cattle. 2. Nutrient metabolism and

rumen fermentation. J. Anim. Sci. 60:347.

Davies, D. R., R. J. Merry, A. P. Williams, E. L. Bakewell, D. K. Lemans and J. K. S. Tweed.

1997. Proteolysis during ensiling of forages varying in soluble sugar content. J. Dairy

Sci. 81: 444.

Davies, H. L., T. F. Robinson, B. L. Roeder, M. E. Sharp, N. P. Johnston, A. C. Christensen, and

G. B. Schaalje. 2007. Digestibility, nitrogen balance, and blood metabolites in Llama

(Lama glama) and alpaca (lama pacos) fed barley or barley alfalfa diets. Small Rumin.

Res. 73:1-7.

CXIV

DeFrain, J. M., J. E. Shirley, E. C. Titgemeyer, A. F. Park, and R. T. Ethington. 2002b. Impact

of feeding a raw soybean hullcondensed corn steep liquor pellet on induced subacute

ruminal acidosis in lactating cows. J. Dairy Sci. 85:2000-2008.

DeFrain, J. M., J. E. Shirley, E. C. Titgemeyer, A. F. Park and R. T. Ethington. 2002a.

Apelletedcombination of raw soyhulls condensed corn steep liquor for lactating cows.

J. Dairy Sci. 85:3403–3410.

DeFrain, J. M., A. R. Hippen, K. F. Kalscheur and D. J. Schingoethe. 2004. Feeding lactose

increases ruminal butyrate and plasma b-hydroxybutyrate in lactating dairy cows. J.

Dairy Sci. 87:2486-2494.

DeFrain, J. M., A. R. Hippen, K. F. Kalscheur and D. J. Schingoethe. 2006. Feeding lactose to

increase ruminal butyrate and the metabolic status of transition dairy cows. J. Dairy Sci.

89: 267-276.

DeHaan, K., T. Klopfenstein, R. Stock, S. Abrams and R. Britton. 1982. Wet distillers co-

products for growing ruminants. Nebraska Beef Rep. MP_43:33.

DeHaan, K., T. Klopfenstein and R. Stock. 1983. Corn gluten feed protein and energy source for

ruminants. Neb. Beef Rep. MP 44:19.

DePeters, E. J. and J. D. Ferguson. 1992. Non protein nitrogen and protein distribution in the

milk of cows. J. Dairy Sci. 75:3192.

Deschard, G., V. C. Mason and R. W. Tetlow. 1988. Treatment of whole crop cereals with

alkali. 4 voluntary intake and growth in steers given wheat ensiled with sod hydroxide,

urea and ammonia. Anim. Feed Sci. Technol. 19:55-66.

Doreau, M., D. Bauchart and A. Kindler. 1987. Effect of fat and lactose supplementation on

digestion in dairy cows. 1. Non lipid components. J. Dairy Sci. 70:64-70.

El Shewy, A., S. Kholif and T. Morsy. 2010. Determination of milk urea nitrogen for the

Egyptian cattle fed the summer and winter diets. J. Ami. Sci. 6(12)

Erdman, R. A. 1988. Dietary buffering requirements of the lactating dairy cow: A review. J.

Dairy Sci. 71: 3246.

Erfle, J. D., S. Mahadevan, R. M. Teather and F. D. Saure. 1983. The performance of lactating

cows fed urea treated corn silage in combination with soybean or fishmeal containing

concentrates. Can. J. Animal Sci. 63:191.

CXV

FAO, 2011a. World Livestock 2011. Livestock in food security. Food and Agriculture

Organization of the United Nations.

Farlin, S.D. 1981.Wet distillers grains for finishing cattle. Anim. Nutr. Health 36:35.

Fanning, K., T. Milton, T. Klopfenstein and M. Klemesrud. 1999. Corn and sorghum distillers

grains for finishing cattle. Nebraska Beef Rep. MP_71_A:32.

Fenderson, C. L. and W. G. Bergen. 1974. Effect of excess dietary protein on steers. J. Anim.

Sci. 39:998-1007.

Forbes, J. M. 1995. Voluntary food intake and diet selection in farm animals. CAB International,

Wallingford, U.K.

Firkins, J.L., L.L. Berger and G.C. Fahey. 1985. Evaluation of wet and dry distillers grains and

wet and dry corn gluten feeds for ruminants. J. Anim. Sci. 60:847.

Firkins, J. L., L. L. Berger, N. R. Merchen and G. C. Fahey. 1986. Effect of forage particles size,

level of feed intake and supplemental protein synthesis and site of nutrient digestion in

steers. J. Anim. Sci. 62: 1081.

Galloway, D. L., A. L. Goetsch, L. A. Forster, A. C. Brake and Z. B. Johnson. 1993. Feed intake

and digestibility by cattle consuming bermudagrass or orchardgrass hay supplemented

with soybean hulls and (or) corn. J. Anim. Sci. 71:3087-3095.

Gill, C. 1997. More value from imported maize. Feed International, August, 23-26.

Glewen, M. J. and A. W. Young. 1982. Effect of ammoniation on the re-fermentation of corn

silage. J. Anim. Sci. 54: 713.

Goering, H. K., D. R. Waldo, H. F. Tyrell and D. J. Thomson. 1991. Composition of

formaldehyde and formic acid treated alfalfa and orchard grass silage harvested at two

maturities and their effects on intake and growth by Holstein heifers. J. Anim. Sci. 69:

4634.

GOP. 2009. Economic Survey of Pakistan 2008-09. Ministry of Food, Agriculture and

Livestock, Islamabad. 17-22.

Gorosito, A. R., J. B. Russell and P. J. Van Soest. 1985. Effect of carbon-4 and carbon-5 volatile

fatty acids on digestion of plant cell walls in vitro. J. Dairy Sci. 68:840.

Grovum, W. L. 1979. Factors affecting the voluntary intake of food by sheep. 2. The role of

distension and tactile input from compartments of the stomach. Br. J. Nutr. 42:425.

CXVI

Gupta, R. S., M. C. Desai, P. M. Talpada and P. C. Shukala. 1990. Effect of corn steep liquor

feeding on growth of crossbred calves. Indian J. Anim. Nutr. 7:279-282.

Haddad, S. and S. Goussous. 2005. Effect of yeast culture supplemented on nutrient intake,

digestibility and growth performance of Awassi lambs. Animal Feed sci. Technol. 118:

343-348.

Hall, M. B. 2004. Short communication: Effect of carbohydrate fermentation rate on estimates

of mass fermented and milk response. J. Dairy Sci. 87:1455-1456.

Hall, M. B. and C. Herejk. 2001. Differences in yields of microbial crude protein from in vitro

fermentation of carbohydrates. J. Dairy Sci. 84:2486-2493.

Hall, M. B. and P. J. Weimer. 2007. Sucrose concentration alters fermentation kinetics,

products, and carbon fates during in vitro fermentation with mixed ruminal microbes. J.

Anim. Sci. 85:1467-1478.

Ham, G. A., R. A. Stock, T. J. Klopfenstein, and R. P. Huffman. 1995. Determining the net

energy value of wet and dry corn gluten feed in beef growing and finishing diets. J.

Anim. Sci. 73:353.

Hanjra, S. H., J. B. David and M. J. A. Akhtar. 1995. Fodder Production. FAO, PAK/88/072.

Smallholders Dairy Development in Punjab. Gujranwala, Pakistan.

Hannah, S. M., R. C. Cochran, E. S. Vanzant, and D. L. Harmon. 1991. Influence of protein

supplementation on site and extent of digestion, forage intake, and nutrient flow

characteristics in steers consuming dormant bluestem-range forage. J. Anim. Sci.

69:2624-2633.

Harris, J.M., E. H. Cash, L. L. Wilson and W. R. Stricklin. 1979. Effects of concentrate level,

protein source and growth promotant: growth and carcass traits. J. Anim. Sci. 49: 613-

619.

Haskins, B. R., M. B. Wise, H. B. Craig and E. R. Barrick. 1967. Effects of levels of protein,

sources of protein and an antibiotic on performance, carcass characteristics, rumen

environment and liver abscesses of steers fed all-concentrate rations. J. Anim. Sci. 26:

430-434.

Hatfield, R. D. 1993. Cell wall polysaccharide interactions and degradability. J. Crop Sci. 285.

Hatfield, E. E., U. S. Ganigus, R. Forbes, A. L. Numann and W. Gaither. 1959. Biuret a source

of NPN for ruminants. J. Anim. Sci. 18:1208.

CXVII

Heldt, J. S., R. C. Cochran, G. K. Stokka, C. G. Farmer, C. P. Mathis, E. C. Tigemeyer and T.

G. Nagaraja. 1999. Effects of different supplemental sugars and starch fed in

combination with degradable intake protein on low-quality forage use by beef steers. J.

Anim. Sci. 77:2793-2802.

Hogan, J. 1996. Feed intake ruminant nutrition and production in the tropic and subtropics.

ACIAR, Canbera, Australia. pp. 47.

Hoover, W. H. 1986. Chemical factors involved in ruminal fiber digestion. J. Dairy Sci. 69:

2755.

Hristov, N. A. and G. A. Broderick. 1996. Synthesis of microbial protein in ruminally-

cannulated cows fed alfalfa silage, alfalfa hay or corn silage. J. Dairy Sci. 79:1627.

Hull, S. R., B. Y. Yang, D. Venzke, K. Kulhavy and R. Montgomery. 1996. Composition of

corn steep water during steeping. J. Agric. Food Chem. 44:1857-1863.

Iqbal, Z., M. Sarwar, M. S. Sajid, R. Z. Abbas, M. K. Khan, M. A. Shahzad and M. N. Khan.

2010. For and against the use of condensed tannins for small ruminant production – a

critical analysis. Egypt. J. Sheep and Goat Sci. 5:147-163.

Javaid, A., M. A. Shahzad, M. Nisa and M. Sarwar. 2011. Ruminal dynamics of ad libitum

feeding in buffalo bulls receiving different level of rumen degradable protein.

Livestock Sci. 135:98–102.

Johnson, R. R., E. W. Klosterman and O. G. Bentley. 1962. Energy value of lactic acid and corn

steepwater and their effects on digestibility of ruminant rations. J. Anim. Sci. 21:887-897.

Kalscheur, K. F., B. B. Teter, L. S. Piperova and R. A. Erdman. 1997. Effect of dietary forage

concentration and buffer addition on duodenal flow of Trans-C18-1 fatty acids and milk

fat production in dairy cows. J. Dairy Sci. 80:2104-2114.

Khalid, M. F., M. A. Shahzad, M. Sarwar, A. U. Rehman, M. Sharif and N. Mukhtar. 2011.

Probiotics and lamb performance: A review. African J. Agric. Research. 6:5198-5203.

Khalid, M. F., M. Sarwar, M. Nisa and Z. Rehman. 2011. Response of growing lambs fed on

different vegetable protein sources with or without probiotics. Int. J. Agric. Biol. 13:

332-338.

Kowalczyk, J., A. Ramirez and C. M. Geerken. 1970. Nitrogen and carbohydrate metabolism in

the rumen and duodenum of young bulls given diets based on molasses/urea. Rev.

Cubana Cienc Agric (Eng ed). 4:187.

CXVIII

Keady, T. W. J. 1996. A review on the effects of molasses treatment of unwilted grass at

ensiling on silage fermentation, digestibility and intake, and on animal performance.

Irish J. Agric. Feed Res. 35:141.

Kellogg, D. W. and F. G. Owen. 1969a. Relation of ration sucrose level and grain content to

lactation performance and rumen fermentation. J. Dairy Sci. 52:657-662.

Kellogg, D. W. and F. G. Owen. 1969b. Alterations of in vitro rumen fermentation patterns with

various levels of sucrose and cellulose. J. Dairy Sci. 52:1458-1460.

Kemp, J. D., M. Mahyuddin, D. G. Ely, J. D. Fox, and W. G. Moody. 1980. Effect of feeding

systems, slaughter weight, and sex on organoleptic properties, and fatty acid

composition of lamb. J. Anim. Sci. 51:321-330.

Kempster, A. J., A. Cuthbcrtson and G. Hanington. 1982. Carcass Evaluation in Livestock

Breeding, Production and Marketing. London: Granada.

Ketelaars, J. J. and B. J. Tolkamp. 1996. Oxygen efficiency and the control of energy flow in

animals and humans. J Anim. Sci. 74:3036-3051.

Khan, M. A., M. Sarwar, M. Nisa and M. S. Khan. 2004. Feeding value of urea treated corncobs

ensiled with or without enzose (corn dextrose) for lactating cross cows. Asian-Aust. J.

Anim. Sci. 17:1093-1097.

Khan, M. A., M. Sarwar, M. Nisa and M. S. Khan. 2004. Feeding value of urea treated corncobs

ensiled with or without enzose (corn dextrose) for lactating crossbred cows. Asian-Aust.

J. Anim. Sci. 7:70.

Knox, M. R. and J. W. Steel. 1999. The effects of urea supplementation on production and

parasitological responses of sheep infected with Haemonchus contartus and

trichostrongylus coubriformis. Vet. Parasitology. 83:123.

Klusmeyer, T. H., G. L. Lynch, J. H. Clark and D. R. Nelson. 1991. Effects of calcium salts of

long chain fatty acids and proportion of forage in diet on ruminal fermentation and

nutrient flow to the duodenum of cows. J. Dairy Sci. 74:2220-2232.

Krishnamoorthy, U. C., T. V. Muscato, C. J. Sniffen. and P. J. Van Soest. 1982. Nitrogen

fractions in selected feedstuffs. J. Dairy Sci. 65:217.

Larson, E. M., R. A. Stock, T. J. Klopfenstein, M. H. Sindt and R. P. Huffman. 1993. Feeding

value of wet distillers co-products from finishing ruminants. J. Anim. Sci. 71:2228.

CXIX

Leek, B. F. 1993. Digestion in the ruminant stomach. M. J. Swenson and W. O. Reece, eds.

Dukes’ physiology of domestic animals. 11th ed. Cornell University Press, Ithaca, NY.

Pages 387-416.

Leng, R. A., N. Jessop and J. Kanjanapruthipong. 1993. Control of feed intake and the efficiency

of utilization of feed by ruminants. Recent Advances in Animal Nutrition in Australia.

Univ. of New England, Armidale, Australia. pp: 70.

Llamas L. G. and D. K. Combs. 1991. Effect of forage to concentrate ratio and intake level on

utilization of early vegetative alfalfa silage by dairy cows. J. Dairy Sci. 74: 526.

Ludden, P.A., J. M. Jones, M. J. Cecava and K. S. Hendrix. 1995. Supplemental protein sources

for steers fed corn based diets: II. Growth and estimated metabolizable amino acid

supply. J. Anim. Sci. 73:1476-1486.

Lupton, C. J., J. E. Huston, B. F. Craddock, F. A. Pfeffer, W. L. Polk. 2007. Comparison of

lamb meat and wool. Small Rumin. Res. 72:133-140.

MacDonald, M. A., H. Krueger and R. Bogart. 1956. Rate and efficiency of gains in beef cattle.

IV. Blood hemoglobin, glucose, urea, amino-acid nitrogen, creatinine, and uric acid of

growing Hereford and Angus calves. Ore. Agr. Exp. Sta. Tech. Bul. 36.

McLaren, G. A., G. C. Anderns, J. A. Welch, C. D. Campbell and G. S. Smith. 1959.

Diethylstilbestrol and length of preliminary period in the utilization of crude biuret and

urea by lambs. J. Anim. Sci. 18:1319.

Mahmood, K. 1988. Effect of alkali and urea treatment on the nutritive value of corn cobs.

M.Sc. Thesis, University of Agriculture, Faisalabad.

Man V. N. and H. Wiktrosson. 2001. The effect of replacing grass with urea treated fresh rice

straw in dairy cow diet. J. Anim. Sci. 14: 1090.

Man, N. V., H. Wiktorsson. 2001. Cassava tops ensiled with or without molasses as additive

effect on quality, feed intake and digestibility by heifers. Asian-Aust. J. Anim. Sci. 14:

624.

Masson, F. M. and A. E. Oxford. 1951. The action of the ciliates of the sheep’s rumen upon

various water-soluble carbohydrates, including polysaccharides. J. Gen. Microbiol. 5:

664-672.

CXX

McCarthy, R. D. Jr., T. H. Klusmeyer, J. L. Vicini and J. H. Clarck. 1989. Effects of source of

protein and carbohydrates on ruminal fermentation and passage of nutrients to small

intestine of lactating cows. J. Dairy Sci. 72:2002.

McCormick, M. E., D. D. Redfearn, J. D. Ward and D. C. Blouin. 2001. Effect of protein source

and soluble carbohydrate addition on rumen fermentation and lactation performance of

Holstein cows. J. Dairy Sci. 84:1686-1697.

McDonald, P. 1981. The biochemistry of silage. John Wiley and Sons, New York, NY.

McDonald, P. and R. Whittenbury. 1977. The ensiling process. In: Chemistry biochemistry of

herbage (Ed. G. W. Butler and R. W. Bailey) Academic Press, NY. pp. 333.

McDonald, P., A. R. Henderson and S. J. E. Heron. 1991. The biochemistry of silage (2nd ed.).

Chalcombe PubI., Church Lane, Kingston, Canterbury, Kent, UK.

McLaren, G. A., G. C. Anderns, J. A. Welch, C. D. Campbell and G. S. Smith. 1959.

Diethylstilbestrol and length of preliminary period in the utilization of crude biuret and

urea by lambs. J. Anim. Sci. 18:1319.

Mekasha, Y. A. Tegegne, A. Yami, N. N. Umunna and I. V. Nsahlai. 2003. Effects of

supplementation of grass hay with non-conventional agro-industrial by-products on

rumen fermentation characteristics and microbial nitrogen supply in rams. Small

Rumin. Res. 50:141-151.

Milton, C. T., R. T. Brandt, Jr. E. C. Titgemeyer and G. L. Kuhl. 1997. Effect of degradable and

escape protein and roughage type on performance and carcass characteristics of

finishing yearling steers. J. Anim. Sci. 75:2834-2840.

Mirza, M. A. and T. Mushtaq. 2006. Effect of supplementing different levels of corn steep liquor

on the post-weaning growth performance of Pak-karacul lambs. Pakistan Vet. J. 26(3):

135-137.

Morrison, I. M. and R.E. Brice. 1984. The digestion of untreated and ammonia-treated barley

straw in an artificial rumen. Anim. Feed Sci. Technol. 10:229-38.

Morse, D., H. H. Head, C. J. Wilcox, H. H. Van Horn, C. D. Hissem and Jr. B. Harris. 1992.

Effects of concentration of dietary phosphorus on amount and route of excretion. J.

Dairy Sci. 75:3039-3049.

Mukhtar, N., M. Sarwar, M. A. Shahzad, S. A. Bhatti and M. Nisa. 2011. Blood dynamics,

carcass characteristics and weight gain in post weaned lohi lambs raised under

CXXI

traditional and high input feeding system. 31st Pakistan Congress of Zoology

(International), 19-21 April, 2011.University of Azad Jammu & Kashmir,

Muzaffarabad.

Mukhtar, N., M. Sarwar, Mahr-un-Nisa and M. A. Sheikh. 2010. Growth response of growing

lambs fed on concentrate with or without ionophores and probiotics. Int. J. Agric. Biol.

12:734-738.

Murphy, T. A., S. C. Loerch, K. E. McClure and M. B. Solomon. 1994. Effects of restricted

feeding on growth performance and carcass composition of lambs subjected to different

nutritional treatments. J. Anim. Sci. 72:3131-3137.

Nisa, M., M. A. Khan, M. Sarwar, W. S. Lee, H. J. Lee, K. S. Ki, B. S. Ahn and H. S. Kim.

2006. Influence of corn steep liquor on feeding value of urea treated wheat straw in

buffaloes fed at restricted diets. Asian-Aust. J. Anim. Sci. 19:1610-1616.

Nisa, M., M. Sarwar and M. A. Khan. 2004a. Influence of ad libitum feeding of urea treated

wheat straw with or without corn steep liquor on intake, in situ digestion kinetics,

nitrogen metabolism, and nutrient digestion in Nili-Ravi buffalo bulls. Aust. J. Agric.

Res. 55:235-241.

Nisa, M., M. Sarwar and M. A. Khan. 2004b. Nutritive value of urea treated wheat straw ensiled

with or without corn steep liquor for lactating Nili-Ravi buffaloes. Asian-Aust. J. Anim.

Sci. 17:825-829.

Nisa, M., M. Sarwar, and M. A. Khan. 2004. Influence of ad libitum feeding of urea treated

wheat straw with or without corn steep liquor on intake, in situ digestion kinetics,

nitrogen metabolism and nutrient digestion in Nili-Ravi buffalo bulls. Aust. J. Agric.

Res. 55:235-239.

NRC. 2001. Nutrient requirements of dairy cattle. 7th revised edition. National Academy Press,

Washington, D. C.

Nsahlai, I. V, M. L. K. Bonsi, N. N. Umunna, Z. Sileshi and S. Bediye. 1998. Feed utilisation

strategies for improved ruminant production in the arid region. Ann. Arid Zone. 37:

283-310.

Oba, M. 2011. Review: Effects of feeding sugars on productivity of lactating dairy cows. Can. J.

Anim. Sci. 91:37-46.

CXXII

Oltjen, R. R. and P. A. Putnam. 1966. Plasma amino acids and nitrogen retention by steers fed

purified diets containing urea or isolated soy protein. J. Nutr. 89:385.

Oltjen, R. R., G. R. Waller, A. B. Nelson and A. D. Timeline. 1963. Ruminant studies with

diammonium phosphate and urea. J. Anim. Sci. 22:36.

Oltjen, R. R., L. L. Slyter, A. R. Koral and E. E. Williams Jr. 1968. Evaluation of biuret, urea,

urea phosphate and uric acid as NPN sources for cattle. J. Nutr. 94:193.

Oltjen, R. R., E. E. Williams, Jr. L. L. Slyter and G. V. Richardson. 1969. Urea versus Biuret in

a Roughage Diet for steers. J. Anim. Sci. 29:816.

Onkuwa, C. F., I. O. A. Isah, A. O. Oni and R. Y. Aderinboye. 2012. Ruminant Animal

Nutrition. University of Nebraska, Lincoln, USA.

Ono, K., B. W. Berry, H. K. Johnson, E. Russek, C. F. Parker, V. R. Cahill and P. G. Althouse.

1984. Nutrient composition of lamb two age groups. J. Food Sci. 49:1233-1239, 1257.

Ortigues, I., J. P. Fontenot and J. G. Ferry. 1988. Digesta flows in sheep fed poor quality hay

supplemented with urea and concentrates. J. Anim. Sci. 66:975.

Owens, F. N. and A. L. Goetsch. 1988. Ruminal fermentation. in D. C. Church, ed. The

ruminant animal digestive physiology and nutrition. Waveland Press Inc., Prospect

Heights, IL. Pages 145_171

Owens, F. N., W. M. Knight and K. O. Nimik. 1973. Intraruminal urea infusion and abomasal

amino acid passage. J. Anim. Sci. 66:975.

Oxford, A. E. 1951. The conversion of certain soluble sugars to a glucosan by holotrich ciliates

in the rurnen of sheep. J. Gen. Microbiol. 5:83-90.

Pakistan Economic Survey. 2012-13. Economic Advisors Wing, Ministry of Finance.

Government of Pakistan, Islamabad.

Penner, G. B., L. L. Guan and M. Oba. 2009. Effect of feeding Fermenten on ruminal

fermentation in lactating Holstein cows fed two dietary sugar concentrations. J. Dairy

Sci. 92:1725-1733.

Penner, G. B. and M. Oba. 2009. Increasing dietary sugar concentration may improve dry matter

intake, ruminal fermentation, and productivity of dairy cows in the postpartum phase of

the transition period. J. Dairy Sci. 92:3341-3353.

Petit, H. V. 2002. Digestion, milk production, milk composition, and blood composition of dairy

cows fed whole flaxseed. J. Dairy Sci. 85:1482-1490.

CXXIII

Petit, H. V. and F. Castonguay. 1994. Growth and carcass quality of prolific cross bred lambs

fed silage with fish meal or different amounts of concentrate. J. Anim. Sci. 72:1849-

1856.

Petit, H. V. and P. M. Flipot. 1992. Sources and feeding levels of nitrogen on growth and

carcass characteristics of beef steers fed grass and hay silage. J. Anim. Sci. 70:867-875.

Plaisance, R., H. V. Petit, J. R. Seoance and R. Rioux. 1997. The nutritive value of canola, heat

treated canola and fish meals as protein supplements for lambs fed grass silage. Anim.

Feed Sci. Tecnol. 68:139-152.

Polan, C. E., D. E. Stieve and J. L. Garrett. 1998. Protein preservation and ruminal degradation

of ensiled forage treated with heat, formic acid, ammonia, or microbial inoculants. J.

Dairy Sci. 81:765.

Ponnampalam, E. N., A. R. Egan, A. J. Sinclair, and B.J. Leury. 2005. Feed intake, growth,

plasma glucose and urea nitrogen concentration, and carcass traits of lambs fed

isoenergetic amounts of canola meal, soybean meal, and fish meal with forage based

diet. Small Rumi. Res. 58:245-252.

Qureshi, Z. I., L. A. Lodhi, H. A. Samad, N. A. Naz and M. Nawaz. 2001. Hematological profile

following immunomodulation during late gestation in buffaloes. Pakistan Vet. J. 21:

148-151.

Ranjhan, S. K. 1993. Animal Nutrition in Tropics, 3rd Ed. New Delhi.

Rausch, K. D. and R. L. Belyea. 2006. The future of co products from corn processing. Appl.

Biochem. Biotechnol. 128:47-86.

Ribeiro, C. V. D. M., S. K. R. Karnati and M. L. Eastridge. 2005. Biohydrogenation of fatty

acids and digestibility of fresh alfalfa or alfalfa hay plus sucrose in continuous culture.

Journal. pages.

Riley, R. R., J. W. Savell, D. D. Johnson, G. C. Smith and M. Shelton. 1989. Carcass grades

rack composition and tenderness of sheep and goats as influenced by market class and

breed. Small Rumin. Res. 2:273-280.

Roseler D. K ., J. D. Ferguson, C. J. Sniffen and J. Herrema. 1993. Dietary protein degradability

effect on plasma and milk urea nitrogen and milk nonprotein nitrogen in Holstein cows.

J. Dairy Sci. 76:525-534.

CXXIV

Ruig, W.G. DE. 1986. Atomic absorption spectrophotometeric determination of calcium,

copper, iron, manganese, potassium, sodium, and zinc in animal feeding stuffs inter

laboratory collaborative studies. J.Asso. official analytical chemists. 69:175-187.

Russel, J. B., H. J. Strobel and S. A. Martin. 1990. Strategies of nutrient transport by ruminal

bacteria. J. Dairy Sci. 73:2996.

Saadullah, M., M. Haque and F. Dolberg. 1981. Effectiveness of ammonification through urea

in improving the feeding value of rice straw in ruminants. Tropical Anim. Prod. 6:30.

Saleh B. A. 1972. Effect of castration on liveweight gains and carcass composition of Kizil

lambs. Technical Report No. 30. Animal Husbandry Research Institute, Haydarabad,

Karaj, Iran.

Sanderson, M. A., J. S. Hornstein and W. F. Wedin. 1989. Alfalfa morphological stage and its

relation to in situ digestibility of detergent fiber fractions of stems. Crop Sci. 29:1315.

Sano, H., H. Sawada, A. Takenami, S. Oda and M. Al-Mamun. 2006. Effects of dietary energy

intake and cold exposure on kinetics of plasma glucose metabolism in sheep. L. Anim.

Phy. Anim. Nutr. 91:1-5.

Sarwar, M., M. A. Shahzad, M. Nisa, S. Amjad. 2011. Nutrient intake, acid base status and

weight gain in water buffalo calves fed different dietary concentrations of sodium

bicarbonate. South African J. Anim. Sci. 41:94-103.

Sarwar, M., M. A. Shahzad, M. Nisa, D. Afzal, M. Sharif and H. A. Saddiqi. 2011. Feeding

value of urea molasses treated wheat straw ensiled with fresh cattle manure for growing

crossbred cattle calves. Tropical Anim. Health and Prod. 43:543-548.

Sarwar, M. M. A. Shahzad, M. Nisa and A. Sufyan. 2007. Influence of bovine somatotropin and

replacement of corn dextrose with concentrate on the performance of mid-lactating

buffaloes fed urea-treated wheat straw. Turk. J. Vet. Anim. Sci. 31:259-265.

Sarwar, M., M. A. Khan and M. Nisa. 2004a. Effect of organic acids or fermentable

carbohydrates on nitrogen fixation and chemical composition of urea treated wheat

straw. Asian-Aust. J. Anim. Sci. 1:98.

Sarwar, M., M. A. Khan and M. Nisa. 2004a. Effect of urea treated wheat straw ensiled with

organic acids or fermentable carbohydrates on ruminal parameters, digestion

kinetics,digestibility, and nitrogen metabolism in Nili-Ravi buffalo bulls fed restricted

diets. Austr. J. Agric. Res. 1:87.

CXXV

Sarwar, M., M. Khan and M. A. Nisa. 2004b. Effect of organic acids or fermentable

carbohydrates on digestibility and nitrogen utilization of urea treated wheat straw in

buffalo bulls. Austr. J. Agric. Res. 55:229.

Sarwar, M., M. A. Khan and M. Nisa. 2003. Nitrogen retention and chemical composition of

urea treated wheat straw ensiled with organic acids or fermentable carbohydrates.

Asian-Aust. J. Anim. Sci. 16:1583-1589.

Sarwar, M., M. A. Khan and Z. Iqbal. 2002a. Feed Resources for Livestock in Pakistan: Status

Paper. Int. J. Agri. Biol. 4:186-192.

Sarwar, M., M. A. Khan, M. Nisa and Z. Iqbal. 2002b. Dairy Industry in Pakistan: A Scenario.

Int. J. Agri. Biol. 3:420

Sarwar, M. and Z. U. Hasan. 2001. Nutrient metabolism in ruminants. Friends science

publishers, Faisalabad, Pakistan.

Sarwar, M and S. A. Chaudhry. 2000. The Rumen: Digestive Physiology and Feeding

Management. Friends Science Publishers, 399-B, Peoples colony 1, Faisalabad,

Pakistan. ISBN # 969-8490-01-9.

Sarwar, M., M. U. Nisa and M. N. Saeed. 1999. Influence of nitrogen fertilization and stage of

maturity of Mott grass (pennisetum purpureum) on its composition, dry matter intake,

ruminal characteristics and digestion kinetics in cannulated buffalo bulls. Anim. Feed

Sci. Technol. 82:121.

Sarwar, M. and M. U. Nisa. 1999. Effect of nitrogen fertilization and stage of maturity of Mott

grass (Penisetum perpureum) on its chemical composition, dry matter intake, ruminal

characteristics and digestibility in buffalo bulls. Asian-Aust. J. Anim. Sci.12: 1035.

Sarwar, M. S. Mahmood, W. Abbas and C. S. Ali. 1996. In situ ruminal degradation kinetics of

forages and feed by products in male Nili-Ravi buffalo calves. Asian-Aust. J. Anim.

Sci. 9:107.

Sarwar, M., M. A. Iqbal, C. S. Ali and T. Khaliq. 1994. Growth performance of male buffalo

calves as affected by using cowpeas and soybean seeds as a source of urease during

urea treated wheat straw ensling process. Egypt. J. Anim. Prod. 2:179.

Sarwar, M., J. L. Firkins and M. L. Eastridge. 1992. Effects of varying forage and concentrate

carbohydrates on nutrient digestibilities and milk production by dairy cows. J. Dairy

Sci. 75:1533–1542.

CXXVI

Sarwar, M., J. L. Firkins and M. L. Eastridge. 1991. Effect of replacing neutral detergent fiber of

forage with soy hulls and corn gluten feed for dairy heifers. J. Dairy Sci. 74:1006-1017.

Schingoethe, D. J. 2004. Corn coproducts for cattle. In Proc. 40th Eastern Nutr. Conf., Ottawa,

ON, Canada. Animal Nutrition Association of Canada. 39-47.

Schingoethe, D. J., E. W. Skyberg and R. W. Bailey. 1980. Digestibility, mineral balance, and

rumen fermentation by steers of rations containing large amounts of lactose or dried

whey. J. Dairy Sci. 63:762-774.

Schingoethe, D. J., and D. P. Casper. 1991. Total lactational response to added fat during early

lactation. J. Dairy Sci. 74:2617-2622.

Scott, T. L., C.T. Milton, G. E. Erickson, T. J. Klopfenstein and R. A. Stock. 2003. Corn

processing method in finishing diets containing wet corn gluten feed. J. Anim. Sci.

81:3182-3190.

Scott, T., T. Klopfenstein, R. Stock and M. Klemesrud. 1997. Evaluation of corn bran and corn

steep liquor for finishing steers. Neb. Beef Rep. MP 67-A:72-74.

Sen, A. R., A. Santra and S. A. Karim. 2004. Carcass yield, composition and meat quality

attributes of sheep and goat under semiarid conditions. Meat Sci. 66:757-763.

Shadnoush, G. H., G. R. Ghorbani and M. A. Edris. 2004. Effect of different energy levels in

feed and slaughter weights on carcass and chemical composition of Lori-Bakhtiari ram

lambs. Small Rumin. Res. 51:243-249.

Shahzad, M. A., N. A.Tauqir, M. Nisa, M. Sarwar, M. Fayyaz and M. A. Tipu. 2011. Effects of

feeding different dietary protein and energy levels on the performance of 12-15 month

old buffalo calves. Tropical Anim. Health and Prod. 43:685-693.

Shahzad, M. A., M. Nisa and M. Sarwar. 2011. Influence of replacing corn grains by enzose

(corn dextrose) on nutrient utilization, thyroid hormones, plasma metabolites and

weight gain in growing lambs. Asian-Aust. J. Anim. Sci. 24:946-951.

Shahzad, M. A., M. Sarwar and M. Nisa. 2011. Evaluation of corn steep liquor as potential

substitute of urea in growing buffalo calves. XXII Animal Production Latin-American

Meeting, October 24-26, Radisson Montevideo Victoria Plaza, Montevideo, Arch.

Lactinoam Prod.Anim.19:1-19.

Shahzad, M. A., M. Sarwar, Mahr-un-Nisa and M. Sharif. 2010. Corn steep liquor, a potential

substitute of urea for growing lambs. Egypt. J. Sheep and Goat Sci. 5:177-190.

CXXVII

Shaver, R. D., L. D. Satter and N. A. Jorgensen. 1988. Impact of forages fiber content on

digestion and digesta passage in lactating dairy cows. J. Dairy Sci. 71:1556.

Shiver, B. J., W. H. Hoover, J. P. Sargent, R. J. Crawford Jr. and W. V. Thayne. 1986.

Fermentation of a high concentrate diet as affected by ruminal pH and digesta flow. J. Dairy

Sci. 69: 413.

Sindhu A. A., M. A. Khan, M. Nisa and M. Sarwar. 2002. Agro-industrial byproducts as a

potential source of livestock feed - Review. Int. J. Agri. Biol. 4:307-310.

Slabbert, N., J. P. Campher, T. Shelby, G. P. Khun and H. H. Meissner. 1992. The influence of

dietary concentration and feed intake level on feedlot steers.1. Digestibility of diets and

rumen parameters. J. Anim. Sci. 6:101.

Slyter, L. L., R. R. Oltjen, E. E. Williams and R. L. Wilson. 1971. Influence of urea, biuret and

starch on amino acid patterns in ruminal bacteria and blood plasma on nitrogen balance of

steers fed high fiber purified diets. J. Nutr. 101:839.

Soderholm, C. G., D. E. Otterby, J. G. Linn, W. P. Hansen, D. G. Johnson and R. G. Lundquist.

1988. Addition of ammonia and urea plus molasses to high moisture snapped ear corn at

ensiling. J. Dairy Sci. 71: 712.

Souza, M. I. L., S. D.Bicudo, L. F. Uribe-Velasquez and A. A. Ramos. 2002. Circadian and

circannual rhythms of T3 and T4 secretios in Polwarth-Ideal rams. Small Rumin. Res.

46:1-5.

Spears, R. A., A. J. Young, and R. A. Kohn. 2003. Whole-farm phosphorus balance on western

dairy farms. J. Dairy Sci. 86:688-695.

Sutton, J. D., J. A. Bines, S. V. Morant and D. J. Napper. 1987. A comparison of starchy and

fibrous concentrates for milk production, energy utilization and hay intake by Friesian

Cows. J. Agric. 109: 375.

SPSS, 1996. Statistical Packages for Social Sciences, Ver. 17, SPSS Inc. Illinois (USA)

Staples, C. R., C. L. Davis, G. C. McCoy and J. H. Clark. 1984. Feeding value of wet corn

gluten feed for lactating dairy cows. J. Dairy Sci. 67:1214-1220.

Steel, R. G. D., J. H. Torrie and D. A. Dickey. 1996. Principles and procedures of Statistics, A

biometrical approach. 3rd Ed. Mc Graw Hills Book, Co. Inc, New York.

Stensig, T. and P. H. Robinson. 1997. Digestion and passage kinetics of forage fiber in dairy

cows as affected by fiber-free concentrate in the diet. J. Dairy Sci. 80:1339.

CXXVIII

Stock, R. A., J. M. Lewis, T. J. Klopfenstein and C.T. Milton. 1999. Review of new information

on the use of wet and dry milling feed co-products in feedlot diets. Proc. Am. Soc.

Anim. Sci. Available at: http://www.asas.org/jas/symposia/proceedings/0924.pdf.

Stock, R. A. and R. A. Britton. 1993. Acidosis in Feedlot Cattle. In: Scientific Update on

Rumensin/Tylan for the Profession Feedlot Consultant. Elanco Animal Health,

Indianapolis. IN. p A_1.

Sutoh, M., Y. Obara and S. Miyamoto. 1996. The effect of sucrose supplementation on kinetics

of nitrogen, ruminal propionate and plasma glucose in sheep. J. Agri. Sci. 126:99-105.

Sutton, J. D. 1968. The fermentation of soluble carbohydrates in rumen contents of cows fed

diets containing a large proportion of hay. Br. J. Nutr. 22:689-712.

Szabo, C., A. J. Jansman, L. Babinszky, E. Kanis and M.W. Verstegen. 2001. Effect of dietary

protein source and lysine: DE ratio on growth performance, meat quality, and body

composition of growing-finishing pigs. J. Anim. Sci. 79:2857-2865.

Talpada, P. M., M. C. Desai, H. B. Desai, Z. N. Patel and P. C. Shukala. 2002. Nutritive value of

corn steep liquor. Indian J. Anim. Nutr. 4:124-125.

Talpada, P. M., M. C. Desai, H. B. Desai, Z. N. Patel and P. C. Shukala. 1987. Nutritive value of

corn steep liquor. Indian J. Anim. Nutr. 4:124-125.

Tariq, M. 1988. Effect of urea-treated wheat and rice straws on nitrogen fractions of ruminal

fluid. M.Sc. Thesis, University of Agriculture, Faisalabad.

Tauqir, N. A., M. A. Shahzad, Mahr-un-Nisa, M. Fayyaz, A. Tipu and M. Sarwar. 2011.

Response of growing buffalo calves to various energy and protein concentrations. Livestock

Sci. 137:66-72.

Tauqir, N. A., M. Sarwar, M. Fayyaz, M. A. Tipu and I, Hussain. 2012. Influence of substitution

of concentrate with molasses and corn steep liquor on nutrient intake, weight gain and feed

conversion efficiency of buffalo calves. J. Anim. Plant Sci. 22:296-300.

Teller, E., M. Vanbelle, M. Foulon, G. Collignon and B. Matatu. 1992. Nitrogen metabolism in

rumen and whole digestive tract of lactating dairy cows fed grass silage. J. Dairy Sci. 75:

1296.

Teller, E., M. Vanbelle, P. Kamatali, G. Collignon, P. Delfosse and S. Hadjiandreou. 1990.

Differences between animals and effect of basal diet for the in situ degradability of grass

silage. J. Anim. Physiol. Anim. Nutr. 64: 233.

CXXIX

Todaro, M., A. Corrao, C. M. A. Barone, M. L. Alicata, R. Schinelli, and P. Giaccone. 2006.

Use of weaning concentrate in the feeding of suckling kids: Effects on meat quality.

Small Rumin. Res. 66:44-50.

Todini, L., A. Malfatti, A. Valbonesi, M. Trabalza-Marinucci and A. Debenedetti. 2007. Plasma

total T3 and T4 concentration in goats at different physiological stages, as affected by

the energy intake. Small Rumin. Res. 68:285-290.

Trenke, A. and C. Ribeiro. 2002. Evaluation of a mixture of corn steep liquor and distillers

solubles as a replacement for corn and supplement in cattle finishing diets. Beef

Research Report. Iowa State University. pages

Trenkle, A. 1997a. Evaluation of wet distillers grains in finishing diets for yearling steers. Beef

Research Report- Iowa State Univ. ASRI 450. pages

Trenkle, A. 1997b. Substituting wet distillers grains or condensed solubles for corn grain in

finishing diets for yearling heifers. Beef Research Report - Iowa State Univ. ASRI 451.

pages

Vallimont, J. E., F. Bargo, T. W. Cassidy, N. D. Luchini, G. A. Broderick and G. A. Varga.

2004. Effects of replacing dietary starch with sucrose on ruminal fermentation and nitrogen

metabolism in continuous culture. J. Dairy Sci. 87:4221-4229.

Van Soest, P. J. 1965. Symposium on factors influencing the voluntary intake of herbage by

ruminants: Voluntary intake in relation to chemical composition and digestibility. J. Anim.

Sci. 24: 834.

Van Soest, P. J., J. B. Robertson, and B. A. Lewis. 1991. Method for dietary fiber, neutral

detergent fiber, and nonstarch polysaccharides in relation to animal nutrition. J. Dairy

Sci. 74:3583-3597.

VanBaale, M. J., J. E. Shirley, E. C. Titgemeyer, A. F. Park, M. J. Meyer, R. U. Lindquist and

R. T. Ethington. 2001. Evaluation of wet corn gluten feed in diets for lactating dairy

cows. J. Dairy Sci. 84:2478-2485.

Vander Pol, K. J., G. Erickson, T. Klopfenstein and M. Greenquist. 2005a. Effect of level of wet

distillers grains on feedlot performance of finishing cattle and energy value relative to

corn. J. Anim. Sci. 83(Suppl. 2):25.

Vander Pol, K. J. G. Erickson and T. Klopfenstein. 2005b. Economics of wet distillers grains

use in feedlot diets. J. Anim. Sci. 83(Suppl. 2):67.

CXXX

Verma, D. N. 1997. A text book of animal nutrition. 1st Ed. R. 814, New Rajinder nagar, New

Delhi.

Virtanen, A. I. 1938. Cattle fodder and human nutrition with special reference to biological

nitrogen fixation. Cambridge University Press, Cambridge.

Virtanen, A. I. 1966. Milk production of cows on protein free feed. Sci. 153:1603.

Waagepeterson, J. and V. K. Thomson. 1977. Effect on digestibility and nitrogen content of

barley straw of different ammonia treatments. Anim. Feed Sci. Technol. 2:131.

Wagner, J. J., K. S. Lusby and G. W. Horn. 1983. Condensed molasses, soluble corn steep

liquor, fermented ammoniated condensed whey as protein sources for beef cattle

grazing dormant native range. J. Anim. Sci. 57:542-552.

Waldo, D. R. and N. A. Jorgensen. 1981. Forages for high animal production: Nutritional factors

and effects of conservation. J. Dairy Sci. 64:1207.

Walker, D. K., E. C. Titgemeyer, J. S. Drouillard, E. R. Loe, B. E. Depenbusch and A. S. Webb.

2006. Effects of ractopamine and protein source on growth performance and carcass

characteristics of feedlot heifers. J. Anim. Sci. 84:2795-2800.

Wanapat, M., F. Sundstol and T. H. Garmo. 1985. A comparison of alkali treatment methods to

improve the nutritive value of straw. I. Dig. and Meta. Anim. Feed Sci. Technol. 12:

295-309.

Weimer, P. J., J. M. Lopez G. and A. D. French. 1990. Effect of cellulose fine structure on

kinetics of its digestion by mixed ruminal microorganisms in vitro. Appl. Environ. Microbiol.

56: 2421.

Wertz, A. E., L. L. Berger, D. B. Faulkner and T.G. Nash. 2001. Intake restriction strategies and

sources of energy and protein during the growing period affect nutrient disappearance,

feedlot performance, and carcass characteristics of crossbred heifers. J. Anim. Sci. 79: 1598-

1610.

West, J. W., P. Mandebvu, G. M. Hill and R. N. Gates. 1998. Intake, milk yield and digestion

by dairy cows fed diets with increasing fiber content from Bermuda grass hay or silage. J.

Dairy Sci. 81: 1599.

Wickersham, E. E., J. E. Shirley, E. C. Titgemeyer, M. J. Brouk, J. M. DeFrain, A. F. Park, D.

E. Johnson and R. T. Ethington. 2004. Response of lactating dairy cows to diets

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containing wet corn gluten feed or a raw soybean hull-corn steep liquor pellet. J. Dairy

Sci. 87:3899-3911.

Wiese, S. C., C. L. White, D. G. Masters, J. T. B. Milton and R. H. Davidson. 2003. Growth and

carcass characteristics of prime lambs fed diets containing urea, lupins or canola meal as a

crude protein source. Aust. J. Exp. Agri. 43:1193-1197.

Williams, P. E. V., G. M. Innes and A. Brewer. 1984. Ammonia treatment of straw via the

hydrolysis of urea. Effect of dry matter and urea concentrations on the rate of

hydrolysis of urea. Anim. Feed Sci. Technol. 11:103.

Wilson, R. K. 1985. Laboratory studies on chemical, electrical resistance and physical changes in

grass silage over the first 14 days. Ir. J. Agri. Res. 24: 39.

Wohlt, J. E. 1989. Use of an inoculant to improve feeding stability and intake of a corn silage

grain diet. J. Dairy Sci. 72: 545.

Wohlt, J. E. and J. H. Clark. 1978. Nutritional value of urea versus preformed protein for

ruminants. J. Dairy Sci. 61:902.

Wohlt, J. E., J. H. Clark and F. S. Blaisdell. 1978. Nutritional value of urea versus preformed

protein for ruminants. II. Nitrogen utilization by dairy cows fed corn based diets containing

supplemental nitrogen from urea or soybean meal. J. Dairy Sci. 61:916.

Wright, K. N. 1987. Nutritional properties and feeding value of corn and its by-products. Pages

447-477 in: Corn Chemistry and Technology. S. A. Watson and P. E. Ramstad, eds. Am.

Assoc. Cereal Chem.: St. Paul, MN.

Younas, M and M. Yaqoob. 2005. Feed resources of livestock in the Punjab, Pakistan. Livest.

Res. Rural Devel. http://www.cipav.org.co/lrrd/lrrd17/2/youn17018.htm.

MUHAMMAD SHAHBAZ QAMAR M.Sc. (Hons.) Animal Nutrition …prr.hec.gov.pk/jspui/bitstream/123456789/7962/1... · I am grateful to Professor Dr. Muhammad Sarwar, Distinguished National

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