TALLOW FOR LAYING HENS (POULTRY, FAT ......Finally, deepest appreciation to my wife, Bushra, for her sacrifice, support, understanding and encouragement throughout my academic program.
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TALLOW FOR LAYING HENS (POULTRY,FAT, PERFORMANCE, AMINO ACIDS).
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Baco, Abdul·Aziz Ishak
TALLOW FOR LAYING HENS
The University of Arizona
University Microfilms
International 300 N. Zeeb Road, Ann Arbor, MI48106
8603334
PH.D. 1985
TALLOW FOR LAYING HENS
by
Abdul-Aziz Ishak Baco
A Dissertation Submitted to the Faculty of the
COMMITTEE ON NUTRITIONAL SCIENCES (GRADUATE)
In Partial Fulfillment of the Requirements for the Degree of
DOCTOR OF PHILOSOPHY
In the Graduate College
THE UNIVERSITY OF ARIZONA
1 985
THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE
As members of the Final Examination Committee, we certify that we have read
the dissertation prepared by Abdul-Aziz Ishak Baco --------------------------------------------
entitled TALLOW FOR LAYING HENS ------------------------------------------------------------
and recommend that it be accepted as fulfilling the dissertation requirement
for the Degree of Doctor of Philosophy
~~ss(L ~ ,K g~i2
Date
Date
Date
Date" /
Final approval and acceptance of this dissertation is contingent upon the candidate's submission of the final copy of the dissertation to the Graduate College.
I hereby certify that I have read this dissertation prepared under my direction and recommend that it be accepted as fulfilling the dissertation requirement.
Dissertation Director Date
STATEMENT BY AUTHOR
This dissertation has been submitted in partial fulfillment of requirements for an advanced degree at the University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library.
Brief quotations from this dissertation are allowable without special permission, provided that accurate acknowledgment of source is made. Request for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his or her judgment the proposed use of the materials is in the interests of scholarship. In all other instances, however, permission must be obtained from the author.
SIGNED
DEDICATION
In the name of ALLAH (God),
the most merciful,
the most compassionate
01 ~ 1 ii 'J \
01 I . 'L......... ~Yr' ... ..)
If .L;~1 .. ~ l\ ~ . U--
·0 . ?" '1
To my parents to whom lowe everything,
To my three daughters (Amena, Asma and Alaa)
with them I shall ask Allah to protect me from the hell fire,
To my lovely wife
iii
ACKNOWLEDGEMENTS
The author is sincerely grateful to Dr. Bobby L. Reid for his
guidance, encouragement and continued moral support throughout the
entire graduate program and the accomplishment of this project.
Appreciation is also due to the committee members, Drs. J. A.
Marchello, R. L. Price, W. H. Brown, and M. R. Selke for their
suggestions and constructive criticisms.
Special thanks to Phyllis Maiorino for her contribution in
editing this dissertation, and to Rebecca Mitchell and Angelo Longo as
well as to the staff of the Poultry Research Center for their technical
assistance during the research period.
The author would like to thank his family members, parents
and brothers, Abdul-Sattar, Mohammad Ali, for their help and
encouragement.
Finally, deepest appreciation to my wife, Bushra, for her
sacrifice, support, understanding and encouragement throughout my
academic program.
I.
II.
III.
TABLE OF CONTENTS
LIST OF TABLES • • • •
LIST OF ILLUSTRATIONS
ABSTRACT • • •
INTRODUCTION
LITERATURE REVIEW
EFFECTS OF ADDED TALLOW ON DIETARY NUTRIENT UTILIZATION Introduction • • • • • Experimental Procedure • Results and Discussion • S UIIIIIla ry . . . . . . . . . . . .
IV. EFFECTS OF TALLOW SUPPLEMENTATION IN MINIMAL AMINO ACID DIETS
HI + Activitl (kcal/d) 90.4cd 92.8c 88.0cde 82.8def 94.8bc 107.2a 102.6ab 79.5 f 92.3X House 10 (19.0°C)
House II (21.6°C) S8.3cde 80.gef 81.2ef 67.3h 79.1 fg 93.8c 91.4c 71.3gh 81. 7Y
a-j,X-YM ' h' h ' •. 'f' d'ff ( < OS) eans W1t 1n a parameter not aV1ng common letter super9cr1pts are 91gn1 1cantly 1 erent P.
.j::-\D
50
increased significantly for both the low protein and Met supplemented
diets (Diets 2 and 3) due to fat supplementation at both temperatures.
In the case of hens fed the 13.6% protein diet (Diet 2), this
improvement in ME intake with tallow supplementation may account for
the increases in egg production through higher amounts of ME available
for production. However, the extra ME consumed by hens fed the Met
supplemented basal diet appeared primarily as gains in body weight.
Average ME intakes for birds housed at 19.0°C were significantly
higher than those at 21.6°C, suggesting that birds housed at 19.0°C
needed around 3% more energy to maintain their body temperature than
those at 21.6°c.
In the conventional cage house (House 10), energy balance was
significantly higher for birds fed the Met supplemented basal diet
(Diet 3) than for those fed the NRC basal diet (Diet 1), indicating a
higher requirement for TSAA under these conditions. Energy balance was
not significantly affected by tallow supplementation in either house
nor by both diet in the insulated and evaporatively cooled house (House
11) (Table 14). Average energy balance was significantly higher at
21.6°C (House 11) than at 19.0°C (House 10).
Gross energetic efficiency dropped significantly from 26 to
23.4% when fat was added to the Met supplemented basal diet (Diet 3) at
19.0°C (House 10) and no significant differences occurred with the
other diets at either temperature. Hens housed at 21.6°C (House 11)
had higher gross energetic efficiencies than those at 19.0°C (House
10). Net energetic efficiency followed the same trend as gross
energetic efficiency.
51
The average maintenance energy requirement of birds housed at
19.0°C (House 10) was 204.2 kcal/d, while those at 21.6°C (House 11)
had a maintenance requirement of. 192.4 kcal/d, about 5.8% less. ME
consumption above maintenance did not differ significantly due to
housing temperature.
No change in starch retention was observed due to diet, fat
addition, or to housing. Protein retention decreased slightly from
27.7 to 25% as fat was added to the diets. On the other hand, fat
retention increased significantly from 58.9 to 73.9% with tallow
supplementation.
Summary
An experiment was conducted to evaluate the effects of
dietary formulation and tallow supplementation on laying hen
performance in two types of housing. Although there are economic
benefits which may be realized from feeding low dietary protein levels,
the results of this study show that reducing the total protein level
below that recommended by the NRC (1984) produced a significant
reduction in egg production in birds housed in a conventional open cage
house (House 10). Met supplementation to provide a total of .60% TSAA
was required for maximum egg production for hens housed in the open
house. A significant increase in egg production was obtained with the
low protein diet (Diet 2) when 3% tallow was added, suggesting that
lower protein levels may be used for laying hens under some conditions
if fat is incorporated in the diet. However, the level of egg
production supported by this combination was significantly below that
obtained with the 17% protein diet (Diet 4), either with or without
added tallow. The limiting nutrient in all of the diets, other than
the 17% protein formulation, appeared to be Lys. The highest egg
production rates were associated with the highest intakes of Lys and
the response appeared to be limited by TSAA intakes iu some of the
diets.
52
For birds housed in the insulated and evaporatively cooled
house (House 11) the diet based on the NRC amino acid requirements
(Diet 2) appeared to be optimal for performance even with a lower
protein level. No additional benefits were obtained in egg production
with the feeding of 3% tallow in any of the diets under these housing
conditions. The main effects of added tallow were improved feed
conversions which, of course, reduce feed costs of producins eggs.
The results of this study indicate that formulation of laying
hen diets based on amino acid requirements without consideration of
total protein level may be used to reduce feed costs of egg production
provided care is taken to maintain adequate intake levels of amino
acids with variation in environmental temperature. The impFovement in
production with added tallow in the conventional house suggests the
need for further research to determine an explanation. TSAA and lysine
intake did not increase as the environmental temperature increased.
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