SUPPLEMENTATION OF AVIZYME ® 1502 TO CORN/SBM/WHEAT DIETS FED TO TURKEY TOM POULTS FROM 0-56 DAYS OF AGE CATALINA TROCHE Thesis submitted to the faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE in Animal and Poultry Sciences (Poultry Nutrition) APPROVED _________________________________ Dr. C. Novak __________________________ ______________________ Dr. A. McElroy Dr. F.W.Pierson December 12, 2005 Blacksburg, VA Keywords: Poult, Avizyme ® 1502, Performance, Ileal digestibilities, Histology Copyright, 2005, Catalina Troche
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SUPPLEMENTATION OF AVIZYME®1502 TO CORN/SBM/WHEAT
DIETS FED TO TURKEY TOM POULTS FROM 0-56 DAYS OF AGE
CATALINA TROCHE
Thesis submitted to the faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of
MASTER OF SCIENCE in
Animal and Poultry Sciences (Poultry Nutrition)
APPROVED
_________________________________ Dr. C. Novak
__________________________ ______________________ Dr. A. McElroy Dr. F.W.Pierson
CHAPTER 2: The effects of Avizyme1502 on poult production, ileal digestibility and intestinal parameters, days 0-21............................................................................. 27
CHAPTER 3: The effects of Avizyme1502 on poult production, ileal digestibility and intestinal parameters, days 0-56............................................................................. 49
and amylase Bacillus subtilis 800 units/gram) would increase metabolizable energy by
140 kcal/kg from corn (matrix value for ME was increased from 3418 to 3558 kcal/kg).
Three additional dietary treatments consisted of the NC supplemented with the microbial
enzyme mixture, AZ1502®, at the respective levels: 250, 500 and 750 g/MT.
1 Meat and bone meal was replaced with Propak after 21 days of age.
30
Table 1. Composition and nutrient content of basal diets 0 to 21 days1
1Table lists Positive Control (treatment 1) and Negative Control (treatment 2). Treatments 3, 4 and 5 were formulated though addition of Avizyme®1502 (xylanase, Trichoderma longibrachiatum 600 units/gram; protease, Bacillus subtilis 8000 units/gram and amylase Bacillus subtilis 800 units/gram) at 250, 500 and 750 g/MT, respectively
2For the duration of the trial: Coban 60 included at 0.06% Positive Control and 0.05% Negative Control; BMD 50 included at 0.05%; Chromic oxide (Cr2O3) included at 0.30% 3Blend of meat and bone meals and blood, Valley Protein, Winchester, VA. 4Supplied per kilogram of mix: iron (FeSO4·H2O), 33.5 g; zinc (ZnO), 214 g; manganese (MnO), 300 g; copper (CuSO4·5H2O), 3.4 g; iodine (Ca Iodate), 2.1 g; selenium (Na2SeO3), 500 μg. 5Supplied per kilogram of mix: vitamin A (retinyl acetate), 30,870,000 IU; vitamin D3, 13,230,000 IU; vitamin E (DL-α-tocopheryl acetate), 66,150 IU; vitamin K3 (menadione dimethypyrimidinol bisulfite), 6,006 mg; thiamin 6,174 mg; riboflavin, 26,460 mg; pyridoxine, 11,025 mg; pantothenic acid (D-calcium pantothenate), 39,690 mg; niacin, 154,350 mg; folic acid, 3,528 mg; biotin, 264 mg; vitamin B12 (cyanocobalamin), 53 mg.
and 5A (16-21 days) as well as a cumulative A (0-21 days).
Apparent Ileal Digestibilities
On days 4 (n=19/pen), 8 (n=14/pen), 12 (n=14/pen), 16 (n=9/pen) and 21 birds
(n=9/pen) were killed by cervical dislocation. Ileal sections, defined as the region from
the Meckel’s diverticulum to the ileocecal junction, were immediately harvested and
contents were obtained through squeezing. Apparent ileal digestibilities of both energy
(E) and protein (P) were estimated using chromic oxide as an inert dietary marker. Prior
to analysis, ileal contents were frozen, freeze dried2 and ground using a Wiley® Mini
2 Labconco FreeZone Plus 12 at -10°C for 48 hours Labconco Corporation, Kansas City, MO
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Mill3 with 40-mesh screen. Diet and ileal samples were prepared according to Williams et
al. (1962) and Cr2O3 levels were analyzed using atomic absorption spectrometry4.
Samples were analyzed in duplicate for gross energy5 in (cal / g) (AOAC, 1990).
Combustion analysis6 was used to determine percent nitrogen which went towards the
calculation of protein digestibility (AOAC, 1990). Apparent digestibilities were
calculated using the following equation (Williams et al., 1962):
Apparent digestibility = 100 – [ 100 * (Cr2O3 of feed / Cr2O3 of ileum)
x (nutrient7 content of ileum / nutrient content of feed)]
Intestinal morphology
On days 4, 8, 12, 16 and 21 an additional bird per pen (n=7/treatment) was killed
by cervical dislocation and five-centimeter sections of the ascending duodenum (prior to
the pancreatic bile ducts), jejunum (medial portion posterior to the bile ducts and anterior
to the Meckel’s diverticulum) and ileum (medial portion posterior to the Meckel’s
diverticulum and anterior to the ileocecal junction) were removed, rinsed in TRIS
buffered saline (Sun et al., 2005), cut into five equal pieces and fixed in 10% neutral
buffered formalin. Each intestinal piece was subsequently cut into 5 mm sections and
placed into cassettes. Cassettes were sent to Histo-Scientific Research Laboratories8
embedded in paraffin, cut to 5 μm thickness and mounted onto slides. Tissue slides were
stained using 0.02% toluidine blue (Churuklan and Schneck, 1981). Pictures were
3 Thomas Scientific, Swedesboro, NJ 4 Perkin Elmer AAnalyst 800 Spectrometer, Perkin Elmer Inc., Wellesley, MA 5 Parr 1271 Automatic Bomb Calorimeter, Parr Instrument Company, Moline, IL 6 Perkin Elmer Series II Nitrogen Analyzer 2410, Perkin Elmer Inc., Wellesley, MA 7 Nutrient in this case, refers to either energy or protein. 8 Histo-Scientific Research Laboratories Inc., Woodstock, VA
33
obtained using either, an Olympus DP 10 camera9, for duodenums from days 16 and 21
(magnification 20x or 40x) mounted to a SZ60 dissecting scope9 or an Olympus DP 709
(magnification 40x) mounted to a BX50 photomicroscope9; all measurements were made
using SigmaScan Pro 510. Measurements of villi height and crypt depth were obtained for
the duodenum (magnification 20x), jejunum and ileum (magnification 40x). Three of the
five possible tissue samples were selected at random for villi height and crypt depth
measurements. Each parameter was measured four times per tissue sample (Figure 1,
n=12 measurements/bird, 7 birds/treatment) (Sun et al., 2005).
9 Olympus America Inc., Melville, NY 10 SPSS Inc., Chicago, IL
34
Figure 1. Measurement of ileum villus height and crypt depth with 40X
magnification. The longer solid line indicates villus height and the shorter one crypt
depth. Each arrow head indicates points of measurement.
Villus Height
Crypt Depth
35
Statistical analysis
Production and digestibility data were analyzed through the MIXED procedure of
SAS (SAS Institute, Cary, NC, 1999) for a randomized complete block design. The
statistical model was as follows: yij = μ + αi + βj + εij with yij = observed dependent
variable, μ = grand mean, αi = ith dietary treatment effect, βj = jth random block effect, εij =
error for treatment i of block j ~ N (0, σε). The lsmeans procedure of SAS was used to
determine dietary treatment means with significance established at P ≤ 0.05. The proc
FREQ function of SAS was used to analyze mortality. Villus heights and crypt depths
were evaluated using the MIXED procedure of a two factorial design with days of age
and diet as factors. The model used was: yijk = μ + αi + βj + (αβ)ij +εijk with yijk = observed
dependent variable, μ = grand mean, αi = days of age treatment effect for level αi, βj =
dietary treatment effect for level βj, (αβ)ij = interactions between levels αi and βj, εijk =
error for kth replicate of (αi,Bj) ~ N (0, σε).
Results
Growth performance
ADG was influenced by treatment within the first twelve days of life (Table 2).
During the period 1A, ADG of poults consuming 500g/MT and 750g/MT supplemented
diets gained significantly less than birds consuming the positive control diet. Birds fed
supplemented diets during periods 2A and 3A had improved ADG compared to those fed
the PC diet. There were no significant differences in ADG past twelve days of age. Prior
to 16 days of age FI remained insignificant (Table 3). Poults fed either enzyme
supplemented diets or NC had increased FI during period 5A compared to those fed PC.
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FCR was unaffected by treatment throughout the duration of the trial (Table 4).
Cumulatively (0-21 days) ADG was improved (P=0.005) with the addition of enzyme at
the 250g/MT and 500 g/MT level (Table 5). However, this improvement in ADG was
coupled with an increase in FI (P=0.006). Cumulative FCR differences were not observed
(P=0.132).
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Table 2. Effect of enzyme supplementation on period ADG (kg/bird/day)1
1 a, b Means within a column without common superscript are significantly different at P <
0.05; 2Positive control (PC), basal diet; 3Negative control (NC), reformulated basal with
140 kcal/kg energy reduction; 4NC with 250 g/MT Avizyme® 1502(xylanase,
1Table lists Positive Control (treatment 1) and Negative Control (treatment 2) for respective periods. Treatments 3, 4 and 5 were formulated though addition of Avizyme®1502 (xylanase, Trichoderma longibrachiatum 600 units/gram; protease, Bacillus subtilis 8000 units/gram and amylase Bacillus subtilis 800 units/gram) at 250, 500 and 750 g/MT, respectively
2For the duration of the trial: Coban 60 included in Positive Control at 0.06% and Negative Control at 0.05%; BMD 50 included at 0.05%; Cr2O3 included at 0.30% 3Soybean meal (SBM) 48% 4Blend of meat and bone meals (MBM) and blood, Valley Protein, Winchester, VA. 5ProPak™ marine and animal protein concentrate. Crude protein no less than 60.00%, crude fat not less than 6.00%, crude fiber not more than 2.00%, calcium not less than 5.75% not more than 6.90%, phosphorus not less than 2.75%
Figure 3. Interaction of age and diet on ileum villus height.
Positive control (PC), basal diet; Negative control (NC), reformulated basal with 140
kcal/kg energy reduction; NC with 250 g/MT Avizyme®1502(xylanase, Trichoderma
longibrachiatum 600 units/gram; protease, Bacillus subtilis 8000 units/gram and amylase
Bacillus subtilis 800 units/gram); NC with 500 g/MT Avizyme®1502; NC with 750 g/MT
Avizyme®1502
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Discussion
No significant differences between treatments were observed in ADG. This is in
contrast to reported increases in broiler ADG and FCR due to enzyme supplementation.
Gracia et al. (2003) reported a 9.4% improvement in ADG coupled with a 4.5%
improvement in feed conversion, when corn-SBM diets were supplemented with α-
amylase. Similarly, when corn-SBM diets (24% crude protein) were supplemented with
an Avizyme-protease mixture growth, feed utilization was improved (Ritz et al., 1995).
Though not significant, there was a tendency for NC and enzyme supplemented diets to
have improved ADG over the PC. One may conclude that the enzyme cocktail was
limited by the high quality substrate utilized in this trial given that the impact of enzyme
is more pronounced when lower quality feedstuffs such as wheat are utilized (Choct et
al., 1995; Dänicke et al., 1999; Bedford et al., 2001). This corn utilized during this trial
was slightly higher in oil and protein over 1999’s U.S. average (Danisco,
correspondence). A 1% increase in oil content is estimated to increase the available
energy in corn by 4.5 kcal/kg (Summers, 2001). The use of corn high in oil and
ultimately, metabolizable energy, may suggest that a more intense matrix drop was
required to elicit treatment differences.
An alternative explanation may lie in a negative interaction between CuSO4 and
Avizyme (Marron et al., 2001). Marron et al. (2001) found that 7-28 day old broilers fed
298 mg/kg of CuSO4 in addition to enzyme (Avizyme 1300 at 1g/kg) had depressed
production, decreased starch and fat digestibility as well as an increase in in vivo digesta
viscosity. CuSO4 may interfere with a number of feed additives including; antibiotics,
arsenicals, histomoniastats and Bio Mos® (Waldroup et al. 2003). The negative impact of
71
copper inclusion may be due to copper’s potential to act as a heavy metal toxin, binding
to exogenous enzymes and effectively causing a change in protein conformation
ultimately leading to enzyme deactivation (Marron et al., 2001).
Zanella et al., (1999) theorized that the improvement in growth seen with the
addition of exogenous enzymes was most likely due to the increased digestibility of the
diets. Increasing the efficiency of digestion would allow more energy to be partitioned
towards growth. In the current trial, digestibility was decreased with the addition of
enzyme in the prestarter (0-21 days) phase. The high inclusion rate of copper sulfate may
have affected the digesta passage rate within the bird. However, by 42 days of age
improvements in digestion were observed with AZ addition, indicating that digestibility
may have been increased without a corresponding response in production values. A
previous study (Pesti et al., 1996) found that copper inclusion of 250mg/kg in excess of
nutritional requirement resulted in significant improvements in body weight gain and
feed efficiency. Thus, there is a possibility that CuSO4 is responsible for the production
improvement, independent of AZ.
Tarachai and coworkers (2000) found that villus growth was regulated by neither
parenteral alimentation nor physical stimulation of the gut. Only enteral absorption of
nutrients would stimulate an increase in villus height. If enteral absorption stimulates
morphological changes in the gut one could conclude that increasing available substrate
for absorption (through the action of endogenous enzyme) would further increase villus
size. Ritz et al., (1995) reported similar findings in poults (0-21d) when fed corn-SBM
diets supplemented with either amylase or xylanase. They found that villus length within
the jejunum and ileum was increased with amylase supplementation (Ritz et al., 1995).
72
These findings were in contrast to the current study. Between 21 and 42 days of age
increase in villus height was similar, however from days 42 to 56 villus height
dramatically increased in the PC diet over that in the other treatments. During the first
seven days of life, lipid digestibility in the bird is low due to limiting rates of bile-salt
production and a lag in the developmental increase in pancreatic lipase secretion
(Klasing, 1998). These effects may be even more pronounced in poults which have a
lower intestinal growth rate than that of chicks (Uni et al., 1999). However, once the
efficiency of bile acid production improves, a diet higher in fat, such as the PC treatment,
may have increased mucosal production and villus height (Sell et al., 1989; Klasing,
1989). Sell et al. (1989) reported that birds fed tallow and corn oil at 10% of their diet,
had increased ADG from 2-28 days over poults fed high carbohydrate, low fat diets. In
addition, poults with 10% dietary fat inclusion tended to have heavier mucosa at 21 days
of age.
The role of AZ remains inconclusive, but upon first glace enzymatic inclusion
appears to improve ADG. However, no significant differences were present between the
NC and the enzyme treatments. One could argue that increasing the amount of corn while
decreasing SBM in the NC created a more metabolically available diet to the bird as
compared to the PC. Another enzyme related improvement occurred on day 42 with E
and P digestibilites improving in those treatments which included enzyme. However, any
further interpretations are limited by the inclusion of CuSO4 in these diets, which has
potential to improve performance independent of AZ.
73
SUMMARY AND CONCLUSIONS
Average daily gain appeared to improve with the addition of enzyme during
periods 2A (8-12 d), 3A (12-16 d), A (0-21 d) and B (21-42 d); ADG dropped with the
addition of enzyme during period 1A. Because previous literature has not reported
negative outcomes of enzyme inclusion, one can only theorize that the depression in
ADG during period 1A had to do with the high inclusion of carbohydrate feedstuffs
compared to fat in the negative control diets. Feed intake increased with the addition of
enzyme during periods 5A (16-21d), A, and B. Period B was the only period in which
depressions in FCR were noted with AZ inclusion. A possible explanation for the
similarity of production between NC and PC fed birds may lie in the birds’ ability to
quickly adjust to high quality carbohydrate diets. A greater adjustment in the dietary
matrix may alleviate this problem. Another may be the potential of CuSO4 to interact with
dry AZ, rendering the enzyme cocktail ineffective.
Ileal digestibility of both E and P appeared to be depressed with the addition of
enzyme during periods 1A, 2A, 3A, 4A, A and B. While literature has reported various
production and digestibility differences with the addition of AZ, none have reported
depressions in digestibility. Marron et al. (2001) suggested that CuSO4 negatively
interacted with dry AZ, though the mechanism by which this depression in digestibility
occurs is not understood.
Morphological measurements observed during this trial revealed no differences
between dietary treatments. This could indicate that nutrient availability was similar
across treatments. Furthermore, a lack of response due to increased enzyme levels could
suggest an interaction with CuSO4.
74
The effects of AZ1502 on poult production are confounded by a number of
factors within this trial including stage of production, type of feedstuff, and feed additive
interactions. However, one goal of this project was to mimic industry production as
closely as possible. If anything, this trial has successfully highlighted potential problems
associated with enzyme use in relation to production.
75
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