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Methionine and Protein Requirements of Turkeys 8 to 16 Weeks of Age
Methionine and Protein Requirements of Turkeys 8 to 16 Weeks of Age L. M. POTTER and J. R. SHELTON Department of Poultry Science, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 (Received for publication April 4, 1979)
1980 Poultry Science 59:1268-1274 INTRODUCTION Based o n t h e National Research Council d a t a ( 1 9 7 7 ) , t h e m e t h i o n i n e requirement of male turkeys 8 to 12 weeks of age and female turkeys 8 to 11 weeks of age is .38%, and t h e methionine plus cystine (total sulfur a m i n o acid) requirement is .75%. Assuming 3,000 kcal ME/kg of diet, t h e m e t h i o n i n e requirement is then 1.27 g/Mcal of ME, and the total sulfur amino acid requirement is 2.50 g/Mcal of ME. F r o m two e x p e r i m e n t s involving a total of 7 5 0 male t u r k e y s b e t w e e n 8 and 12 weeks of age, Murillo and Jensen ( 1 9 7 6 ) reported t h a t t h e methionine requirement is between 1.27 and 1.43 g/Mcal ME. T h e m e t h i o n i n e plus cystine c o n t e n t of their corresponding diets was between 2.39 and 2.55 g/Mcal ME. Relatively little o t h e r research has been c o n d u c t e d to determine t h e t o t a l sulfur amino acid requirem e n t of t u r k e y s after eight weeks of age. The purpose of this s t u d y was t o d e t e r m i n e t h e m e t h i o n i n e or total sulfur amino acid requirements of t u r k e y s fed varying levels of protein from 8 to 12 and from 12 t o 16 weeks of age. Based u p o n t h e results of this s t u d y and of a previous s t u d y (Potter and Shelton, 1 9 7 9 ) , t h e protein requirements of male and female t u r k e y s t h r o u g h 16 weeks of age were determined.
MATERIALS AND METHODS Two series of four e x p e r i m e n t s each were c o n d u c t e d with a total of 1,420 m e d i u m size t u r k e y s from 8 to 12 weeks of age (Series 1) and from 12 to 16 weeks of age (Series 2). T u r k e y s of a m e d i u m size strain, propagated at Virginia Polytechnic Institute and State University, were used in t h e first three experiments while Alpine Medium White turkeys were used in t h e fourth experiment. At 8 weeks of age, t h e turkeys were randomized into nine experimental groups for each sex. Each group of 18 to 22 t u r k e y s was placed in a pen of 2.74 X 3.66 m dimensions with shavings as a floor covering. Feed and water were supplied ad libitum, and artificial light was provided continuously. The composition of t h e practical-type 18% protein diet is presented in Table 1. By adding increments of 7.5% dehuUed soybean meal in t h e place of an equal a m o u n t of ground yellow corn, t w o additional diets containing 21 and 24% protein were formed. T o each of these diets, DL-methionine was added at 0, .2, and .4% t o form a 3 X 3 factorial arrangement of dietary t r e a t m e n t s . Each diet was fed t o one pen of male and o n e pen of female t u r k e y s from 8 t o 12 weeks of age in each of four experiments.
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ABSTRACT Turkeys of medium size strains were fed nine diets varying in protein and added methionine content from 8 to 12 and from 12 to 16 weeks of age. Four experiments with a 3 X 3 factorial design were conducted for each age period. Changing the protein content from 18 to 21% and from 21 to 24% during the 8- to 12-week period increased body weight gain by 11.2 and 5.1%, respectively. Changing the protein content from 15 to 18% and from 1 8 t o 21% during the 12-to 16-week period increased body weight gains by 16.7 and 5.4%, respectively. Added methionine at the .2 and .4% levels increased body weight gains by 10.3 and 11.7% from 8 to 12 weeks and 3.5 to 2.3% from 12 to 16 weeks, respectively. The total sulfur amino acid requirements of Medium White turkeys during the 8- to 12- and 12- to 16-week periods were about .93 and .75%, respectively. Using data from the current and previous studies (Potter and Shelton, 1979), we calculated multiple regression analyses of percentage increase in body weight gains (Y) of males or females during 2-week periods from increasing the dietary protein content by 3% on percent protein (Xl) in the diet and average age (X 2 ) of the turkeys. From these regressions, the protein requirement of Medium White turkeys is about 30.3% at one day of age and decreases .61 and .78 percentage units per week for males and females, respectively.
METHIONINE AND PROTEIN REQUIREMENT OF TURKEYS TABLE 1. Composition of basal ration containing 18% protein Ingredients
g/kg
Ground yellow corn Hydrolyzed animal and vegetable fat Dehulled soybean meal Meat and bone scraps Corn distillers dried grains with solubles Defluorinated phosphate Iodized salt Trace mineral mix 3 Vitamin and feed additive premixb Total
649.31 60 215 25 15 30 4 .5 1.19 1,000.00
Supplied the following vitamins and feed additives per kilogram of diet: vitamin A, 6,600 IU; vitamin D 3 , 2,200 ICU; vitamin E, 2.2 IU; menadione sodium bisulfite complex, 1.76 mg; riboflavin, 3.3 mg; Dcalcium pantothenate, 21 mg; niacin, 33 mg; choline chloride, 250 mg; vitamin B 1 2 , 6.6 meg; ethoxyquin, 62.5 mg; and erythromycin thiocyanate, 11 mg.
At 12 weeks of age, t h e t u r k e y s within each sex were re-randomized into nine n e w pens. Diets containing 1 5 , 18, or 2 1 % p r o t e i n and 0, .2, or .4% added DL-methionine were fed t o one pen of male and one pen of female t u r k e y s
from 12 to 16 weeks of age in each of four additional e x p e r i m e n t s . T h e 15% protein diet was formed b y adding 7.5% g r o u n d yellow corn in t h e place of an equal a m o u n t of dehulled soybean meal of t h e 18% protein diet. T h e values used t o calculate t h e n u t r i e n t c o n t e n t of t h e diets and t h e p r o t e i n , m e t h i o nine, and cystine c o n t e n t s of t h e diets w i t h o u t added m e t h i o n i n e are presented in Table 2. T h e diets were prepared for each e x p e r i m e n t by first blending all constant ingredients, which a m o u n t e d t o 8 4 . 6 % of each diet. A p p r o p r i a t e a m o u n t s of each variable were m i x e d with t h e constant ingredients t o form each of t h e nine diets within each experiment. Analyses of samples of diets from each e x p e r i m e n t for protein c o n t e n t were found within t h e expected range. T h e t u r k e y s were weighed in groups or individually at 2-week intervals. Mortality records were k e p t daily, and average feed c o n s u m p t i o n s were calculated b y 2-week periods. Analyses of variance of average b o d y weight gains, feed c o n s u m p t i o n s , and feed efficiencies by 2- and 4-week periods were calculated. RESULTS AND DISCUSSION Series 1. Results of t h e first four experiments are presented in Table 3. Plots of t h e b o d y weights of t h e t u r k e y s on levels of added m e t h i o n i n e and o n t o t a l sulfur amino acids in
TABLE 2. Assumed composition of feed ingredients and calculated nutrient content of diets without added methionine Protein
Methionine
Cystine
TSAA a
(%)
(%)
(%)
(%)
3,307 7,005
9
.18
.16
.34
2,469 1,914 2,447
49 50 27
.72 .67 .60
.73 .35 .40
1.45 1.02 1.00
3,185 3,122 3,060 3,248 3,185 3,122
18 21 24 15 18 21
.297 .338 .379 .257 .297 .338
.276 .318 .361 .233 .276 .318
Metabolizable energy (kcal/kg) Ingredient Ground yellow corn Hydrolyzed animal and vegetable fat Dehulled soybean meal Meat and bone scraps Corn distillers dried grain with solubles Experiment number 1 through 4 5 through 8
Total sulfur amino acids.
.573 .656 .740 .490 .573 .656
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a Contained manganous oxide, zinc oxide, ferrous carbonate, ferrous sulfate, copper oxide, calcium iodate, cobalt carbonate, and calcium carbonate, and supplied the following in milligrams per kilogram of diet: manganese, 60; zinc, 60; iron, 20; copper, 2.5; iodine, 1 ;and cobalt, .225.
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POTTER AND SHELTON
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TABLE 3. Body weight gains, feed consumptions, and feed efficiencies of turkeys between 8 and 12 weeks of age (Series 1) Added methionine (%)
Protein 0
(%)
.4
Average
1.438 1.536 1.593 1.523
1.403 1.610 1.616 1.543
1.355 1.507 1.584
3.902 3.968 4.039 3.970
3.902 4.023 4.004 3.976
3.838 3.941 4.055
.2 •
1.224 1.374 1.544 1.381
18 21 24 Average
3.709 3.831 4.121 3.887 .3297 .3584 .3744 .3541
18 21 24 Average
.3681 .3872 .3940 .3831
.3578 .3984 .4021 .3861
.3519 .3813 .3902
Each value is the average of eight values representing the turkeys in four pens of males and four pens of females. Differences required for significance (P<.05) between any two values are .105 kg for body weight gain, .166 kg for feed consumption, and .0197 for feed efficiency. Body weight gain divided by feed consumption.
t h e diets at each level of protein are presented in Figure 1. Analyses of variance of t h e d a t a for b o d y weight gains, feed c o n s u m p t i o n s , and feed efficiencies are presented in Table 4. By increasing t h e p r o t e i n c o n t e n t of t h e diets from 18 to 21 and from 21 to 2 4 % during t h e period b e t w e e n 8 and 12 weeks of age, b o d y weight gains increased 11.2 and 5 . 1 % , feed c o n s u m p t i o n increased 2.7 and 2.9%, and feed efficiencies increased 8.4 and 2 . 3 % , respectively. Differences of 4 . 1 , 2.4, and 3.0% in average b o d y weight gains, feed c o n s u m p -
<9
* 1.7 z
<
^—3Z*
° 1.6 WEIGt
1-
•
/
18 U v/^^ £ / Su
•
/
£ ,, / ADDED METHIONINE,%
.5 .6 .7 .8 .9 1.0 I.I TOTAL SULFUR AMINO ACIDS, %
FIG. 1. Plot of 8- to 12-week body weight gain in kilograms on percent added methionine or percent total sulfur amino acids in the diet.
tions, and feed efficiencies, respectively, for these comparisons were required for significance (P<.05). By adding m e t h i o n i n e to t h e diets at t h e .2 and .4% levels, b o d y weight gains were increased 10.3 and 11.7% ( P < . 0 0 1 ) , respectively. Feed c o n s u m p t i o n s were increased slightly but n o t significantly ( P > . 0 5 ) b y these additions (2.1 and 2 . 3 % , respectively). Feed efficiencies were increased 8.2 and 9.0% ( P < . 0 0 1 ) , respectively. T h e interaction effects of m e t h i o n i n e x protein were small and significant only in t h e feed c o n s u m p t i o n m e a s u r e m e n t s (Table 4). Based u p o n t h e plot of 8- t o 12-week b o d y weight gains (Figure 1), t h e addition of .2% added m e t h i o n i n e t o t h e 18% protein diet significantly increased b o d y weight gains 17.5%, b u t t h e addition of .4% m e t h i o n i n e failed to increase b o d y weight gains further. It is postulated, therefore, t h a t o t h e r amino acids b e c o m e limiting in t h e 18% protein diet during this age period. F r o m t h e plots of t h e b o d y weight gains on total sulfur amino acids in t h e diet (Fig. 1), t h e b o d y weight gains of t u r k e y s during this period appear to be a function of t h e total sulfur amino acids in t h e diet, with t h e exception of t h e diet containing 18% protein and .4% added
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18 21 24 Average
a
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TABLE 4. Analyses of variance of body ;weight gains, feed consumptions, and feed efficiencies of turkeys between 8 and 12 weeks of age (Series 1) Mean squares Degrees of freedom
Source
Diet Protein Methionine Methionine X Protein Sex
Feed consumptions
Feed efficiencies
X 10~ 4
X 10~"
X 10~ 6
1,398*** 3,260*** 1,879***
1,223*** 2,801*** 603
4,461*** 9,644* ** 7,476***
30,702***
744* 127,899***
10,279***
74 135 25 68
184 125 78 267
229 330 202 191
227
3,355*** 282 110 150 69
25,848*** 303 272 364 181
361
9,301*** 1,964** 384 444 325
P<-05.
** P<.01. * ** P<.001.
methionine. However, considering only diets containing 0 and .2% added methionine, it appears that the increased body weight gain was greater from protein than expected from its sulfur amino acid contribution when compared to the increased body weight gain from added methionine per se. Based on multiple regressions of 8- to 10-week (YO, 10- to 12-week (Y 2 ), and 8- to 12-week (Y 3 ) body weight gain in kilograms on percent added methionine (X!) and percent protein (X 2 ) in the diets, using only the diets containing 0 and .2% added methionine, the following equations were obtained: Y, = .186 + .263 X! + .0218 X 2 Y 2 = .365 + .446 X! + .0177 X 2 Y 3 = .551 + .710X! + .0395 X 2 By dividing the value for b 2 by the value for b ! , the growth promoting effects of protein in comparison to that from methionine were 8.3, 4.0, and 5.6% from the respective three equations. The growth promoting effect of protein was expected to be 1.35 or 2.77% of that from added methionine if methionine or total sulfur amino acids, respectively, was the limiting
nutrient. Because the b 2 to b t ratios are significantly larger than expected, it is possible that the sulfur amino acid content of dehulled soybean meal was underestimated or that the dehulled soybean meal is contributing another growth promoting compound. If a regression line is calculated from the 8to 12-week body weight gains in kilograms on total sulfur amino acids in percent of the diet using only the diets containing 0 and .2% added methionine, the following equation is obtained: Y = .748 + .926X Using the diets containing 21 and 24% protein and .4% added methionine as providing the optimum body weight gain (Y = 1.613 kg), the total sulfur amino acid requirement of turkeys between 8 and 12 weeks of age was .93% or 3.04 g/Mcal ME. These values differ from .75% or 2.50 g/Mcal ME as estimated by the NRC (1977). Series 2. The results from the second series of four experiments are presented in Table 5. Plots of body weights of the turkeys on levels of added methionine and on total sulfur amino acids in the diets at each level of protein are presented in Figure 2. Analyses of variance of the data for body weight gains, feed consump-
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Sex X Diet Sex X Protein Sex X Methionine Sex X Methionine X Protein Experiment Experiment X Sex Error Experiment X Diet Experiment X Diet X Sex
8 2 2 4 1 8 2 2 4 3 3 48 24 24
Body weight gains
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TABLE 5. Body weight gains, feed consumptions, and feed efficiencies of turkeys between 12 and 16 weeks of age (Series 2) Added methionine (%)
(%)
0
.2
.4
Average
15 18 21 Average
1.359 a 1.559 1.680 1.533
1.400 1.646 1.713 1.587
1.381 1.624 1.699 1.568
1.380 1.610 1.697
15 18 21 Average
5.251 5.505 5.751 5.502
5.250 5.570 5.534 5.451
5.304 5.555 5.560 5.473
5.268 5.543 5.615
Feed c
.2647 .2923 .3067 .2879
.2584 .2893 .3026 .2834
.2601 .2873 .2991
Each value is the average of eight values representing the turkeys in four pens of males and four pens of females. Differences required for significance (P<.05) between any two values are .116 kg for body weight gain, .224 kg for feed consumption, and .0145 for feed efficiency. Body weight gain divided by feed consumption.
tions, and feed efficiencies are presented in Table 6. Body weight gains were increased 16.7 and 5.4% by increasing the protein level of the diet from 15 to 18% and from 18 to 21%, respectively, during the 12- to 16-week period. Accompanying increases in feed consumption of 5.2 and 1.3% and in feed efficiency of 10.5 and 4.1%, respectively, were observed. Differences of 4.3, 2.4, and 3.0% in average body weight gains, feed consumptions, and feed
~
0 .2 .4 ADDED METHIONINES
.4 .5 .6 .7 .8 .9 1.0 I.I TOTAL SULFUR AMINO ACIDS, 1.
FIG. 2. Plot of 12- to 16-week body weight gain in kilograms on percent added methionine or percent total sulfur amino acids in the diet.
efficiencies, respectively, for the protein comparisons were necessary for significance. Body weight gains and feed consumptions were not significantly affected by the addition of methionine to the diets. Feed efficiency was increased 4.6% (P<.05) by the addition of .2% methionine to the diets. Based on a plot of the body weight gains on total sulfur amino acids (Fig. 2), one or more amino acids other than methionine and cystine appear limiting in the 15 and 18% protein diets. A requirement for total sulfur amino acids can not be precisely measured from the data in this series of experiments but appears to be about .75% or 2.40 g/Mcal ME compared to .65% or 2.16 g/Mcal ME as estimated by the NRC (1977). An interaction of protein x sex was also observed in this series (Table 6). The increases in body weight gain from increasing the protein content of the diet from 15 to 18% and from 18 to 21% were 21.1 and 5.8% for males in contrast to 10.4 and 4.8% for females, respectively. The body weight gains of the male turkeys fed the 15, 18, and 21% protein diets from 14 to 16 weeks of age were .869, 1.004, and 1.061 kg in contrast to .572, .583 and .579 kg for female turkeys, respectively. This lack of
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.2573 .2803 .2881 .2752
15 18 21 Average
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TABLE 6. Analysis of variance of body weight gains, feed consumptions, and feed efficiencies of turkeys between 12 and 16 weeks of age (Series 2) Mean squares Degrees of freedom
Source
8 2 2 4 1 8 2 2 4 3 3 48 24 24
Feed consumptions
Feed efficiencies
X 10~"
X 10""
X 10~6
1,667*** 6,445*** 181 21 74,080*** 366 1,290*** 21 76 9,074*** 692** 134 184 84
2,330*** 8,029*** 156 568 379,306*** 306 554 148 262 24,535*** 4,250*** 495 608 382
2,703*** 9,605*** 993* 106 30,160*** 461 1,710*** 19 57 29,070*** 141 207 293 122
P<.05.
** P<.01. ** *
P<.001.
increase in b o d y weight gains of females for added protein from 14 t o 16 weeks was responsible for t h e interaction of p r o t e i n X sex in t h e b o d y weight gains (Table 6 ) . Females were n o t gaining weight as rapidly during t h e 14- to
16-week period as in t h e 1 2 - t o 14-week period (.579 as compared to . 6 6 4 kg, respectively). As a result, t h e apparent protein requirement for females was n o t as great as for males during this period.
TABLE 7. Percentage increase in body weight gain from adding protein to the diet3 Age (weeks) in diet (%)
Sex
0-2
2-4
4-6
6-8 • Increase
30 over 27
27 over 24
24 over 21
21 over 18
18 over 15
Males Females Both Males Females Both Males Females Both Males Females Both Males Females Both
3.7 3.1 3.2 8.4 15.8 11.9 15.2 12.6 13.8
7.9 4.8 6.4 14.6 17.3 15.8 26.2 20.5 23.6
8.1 5.6 7.0 12.8 12.2 12.5 20.7 25.2 22.7
3.7 3.8 3.8 15.0 9.9 12.7 17.0 23.7 20.0
8-10
10-12
12-14
14-16
6.1 9.5 7.5 27.5 18.9 23.8
5.6 -.7 3.3 15.5 1.8 10.1
,
7.1 5.9 6.6 12.1 14.0 12.9
5.9 1.3 3.9 9.6 9.8 9.7
Includes data to eight weeks of age from one previous study (Potter and Shelton, 1979).
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Diet Protein Methionine Methionine X Protein Sex Sex X Diet Sex X Protein Sex X Methionine Sex X Methionine X Protein Experiment E x p e r i m e n t X Sex Error E x p e r i m e n t X Diet E x p e r i m e n t X Diet X Sex
Body weight gains
POTTER AND SHELTON
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in Table 7. These d a t a for male and female t u r k e y s are presented graphically in Figures 3 and 4. By calculating multiple regressions of percent increase in average b o d y weight gain of males ( Y , ) or females ( Y 2 ) on age of t u r k e y s in weeks ( X i ) and percent protein in diet ( X 2 ) , t h e following e q u a t i o n s were o b t a i n e d :
Yi = 71.5 - 1.407 Xi - 2.378 X 2 Y 2 = 79.3 - 2.040 Xi - 2.602 X 2
Protein Requirement of Medium White Turkeys at Various Ages. T h e percentage increase in b o d y weight gain from adding protein t o diets of male and female t u r k e y s by 2-week periods o b t a i n e d in a previous s t u d y to 8 weeks of age (Potter and Shelton, 1979) and in this study from 8 to 16 weeks of age are presented
ACKNOWLEDGMENTS Vitamins were supplied by Agricultural Processing Corporation, Salem, VA, and by Hoffmann-LaRoche, Inc., Nutley, NJ.
REFERENCES
2
4
6
8
10
12
AGE AT END OF P E R I O D ,
14
16
WEEKS
FIG. 4. Plot of percent increase in body weight gain from increasing the protein content of the diet on age of female turkeys by 2-week periods.
Murillo, M. G., and L. S. Jensen, 1976. Methionine requirement of developing turkeys from 8-12 weeks of age. Poultry Sci. 55:1414—1418. National Research Council, 1977. Nutrient requirements of domestic animals. Number 1. Nutrient requirements of Poultry. Nat. Acad. Sci., Washington, DC. Potter, L. M., and J. R. Shelton, 1979. Methionine and protein requirements of young turkeys. Poultry Sci. 58:609-615.
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AGE AT END OF PERIOD, WEEKS FIG. 3. Plot of percent increase in body weight gain from increasing the protein content of the diet on age of male turkeys by 2-week periods.
T h e mid-point of t h e range in age and t h e lower protein level given in Table 7 were used in t h e regression. Where t h e p e r c e n t increase in b o d y weight gain of t u r k e y s from feeding a given level of protein over a lower level becomes zero, t h e lower level of protein is considered t h e protein requirement at t h e stated age. T h e p r o t e i n requirement of male turkeys at t h e older ages is significantly ( P < . 0 5 ) higher t h a n of female t u r k e y s . T h e d a t a of Series 2 and also the pooled d a t a r e p o r t e d in Table 7 and Figures 3 and 4 s u p p o r t this conclusion. Based u p o n these multiple regressions, protein requirements for M e d i u m White male t u r k e y s at 0, 4, 8, 12, and 16 weeks are 3 0 . 1 , 27.7, 2 5 . 3 , 2 3 . 0 , and 20.6%, respectively, and for female t u r k e y s 30.5, 2 7 . 3 , 2 4 . 2 , 2 1 . 1 , and 17.9%, respectively. Within the limits of these studies, t h e protein requirement of Medium White t u r k e y s is a b o u t 30.3% at one day of age and decreases .61 and .78 percentage units per week for males and females, respectively.
1980 Poultry Science 59:1268-1274 INTRODUCTION Based o n t h e National Research Council d a t a ( 1 9 7 7 ) , t h e m e t h i o n i n e requirement of male turkeys 8 to 12 weeks of age and female turkeys 8 to 11 weeks of age is .38%, and t h e methionine plus cystine (total sulfur a m i n o acid) requirement is .75%. Assuming 3,000 kcal ME/kg of diet, t h e m e t h i o n i n e requirement is then 1.27 g/Mcal of ME, and the total sulfur amino acid requirement is 2.50 g/Mcal of ME. F r o m two e x p e r i m e n t s involving a total of 7 5 0 male t u r k e y s b e t w e e n 8 and 12 weeks of age, Murillo and Jensen ( 1 9 7 6 ) reported t h a t t h e methionine requirement is between 1.27 and 1.43 g/Mcal ME. T h e m e t h i o n i n e plus cystine c o n t e n t of their corresponding diets was between 2.39 and 2.55 g/Mcal ME. Relatively little o t h e r research has been c o n d u c t e d to determine t h e t o t a l sulfur amino acid requirem e n t of t u r k e y s after eight weeks of age. The purpose of this s t u d y was t o d e t e r m i n e t h e m e t h i o n i n e or total sulfur amino acid requirements of t u r k e y s fed varying levels of protein from 8 to 12 and from 12 t o 16 weeks of age. Based u p o n t h e results of this s t u d y and of a previous s t u d y (Potter and Shelton, 1 9 7 9 ) , t h e protein requirements of male and female t u r k e y s t h r o u g h 16 weeks of age were determined.
MATERIALS AND METHODS Two series of four e x p e r i m e n t s each were c o n d u c t e d with a total of 1,420 m e d i u m size t u r k e y s from 8 to 12 weeks of age (Series 1) and from 12 to 16 weeks of age (Series 2). T u r k e y s of a m e d i u m size strain, propagated at Virginia Polytechnic Institute and State University, were used in t h e first three experiments while Alpine Medium White turkeys were used in t h e fourth experiment. At 8 weeks of age, t h e turkeys were randomized into nine experimental groups for each sex. Each group of 18 to 22 t u r k e y s was placed in a pen of 2.74 X 3.66 m dimensions with shavings as a floor covering. Feed and water were supplied ad libitum, and artificial light was provided continuously. The composition of t h e practical-type 18% protein diet is presented in Table 1. By adding increments of 7.5% dehuUed soybean meal in t h e place of an equal a m o u n t of ground yellow corn, t w o additional diets containing 21 and 24% protein were formed. T o each of these diets, DL-methionine was added at 0, .2, and .4% t o form a 3 X 3 factorial arrangement of dietary t r e a t m e n t s . Each diet was fed t o one pen of male and o n e pen of female t u r k e y s from 8 t o 12 weeks of age in each of four experiments.
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ABSTRACT Turkeys of medium size strains were fed nine diets varying in protein and added methionine content from 8 to 12 and from 12 to 16 weeks of age. Four experiments with a 3 X 3 factorial design were conducted for each age period. Changing the protein content from 18 to 21% and from 21 to 24% during the 8- to 12-week period increased body weight gain by 11.2 and 5.1%, respectively. Changing the protein content from 15 to 18% and from 1 8 t o 21% during the 12-to 16-week period increased body weight gains by 16.7 and 5.4%, respectively. Added methionine at the .2 and .4% levels increased body weight gains by 10.3 and 11.7% from 8 to 12 weeks and 3.5 to 2.3% from 12 to 16 weeks, respectively. The total sulfur amino acid requirements of Medium White turkeys during the 8- to 12- and 12- to 16-week periods were about .93 and .75%, respectively. Using data from the current and previous studies (Potter and Shelton, 1979), we calculated multiple regression analyses of percentage increase in body weight gains (Y) of males or females during 2-week periods from increasing the dietary protein content by 3% on percent protein (Xl) in the diet and average age (X 2 ) of the turkeys. From these regressions, the protein requirement of Medium White turkeys is about 30.3% at one day of age and decreases .61 and .78 percentage units per week for males and females, respectively.
METHIONINE AND PROTEIN REQUIREMENT OF TURKEYS TABLE 1. Composition of basal ration containing 18% protein Ingredients
g/kg
Ground yellow corn Hydrolyzed animal and vegetable fat Dehulled soybean meal Meat and bone scraps Corn distillers dried grains with solubles Defluorinated phosphate Iodized salt Trace mineral mix 3 Vitamin and feed additive premixb Total
649.31 60 215 25 15 30 4 .5 1.19 1,000.00
Supplied the following vitamins and feed additives per kilogram of diet: vitamin A, 6,600 IU; vitamin D 3 , 2,200 ICU; vitamin E, 2.2 IU; menadione sodium bisulfite complex, 1.76 mg; riboflavin, 3.3 mg; Dcalcium pantothenate, 21 mg; niacin, 33 mg; choline chloride, 250 mg; vitamin B 1 2 , 6.6 meg; ethoxyquin, 62.5 mg; and erythromycin thiocyanate, 11 mg.
At 12 weeks of age, t h e t u r k e y s within each sex were re-randomized into nine n e w pens. Diets containing 1 5 , 18, or 2 1 % p r o t e i n and 0, .2, or .4% added DL-methionine were fed t o one pen of male and one pen of female t u r k e y s
from 12 to 16 weeks of age in each of four additional e x p e r i m e n t s . T h e 15% protein diet was formed b y adding 7.5% g r o u n d yellow corn in t h e place of an equal a m o u n t of dehulled soybean meal of t h e 18% protein diet. T h e values used t o calculate t h e n u t r i e n t c o n t e n t of t h e diets and t h e p r o t e i n , m e t h i o nine, and cystine c o n t e n t s of t h e diets w i t h o u t added m e t h i o n i n e are presented in Table 2. T h e diets were prepared for each e x p e r i m e n t by first blending all constant ingredients, which a m o u n t e d t o 8 4 . 6 % of each diet. A p p r o p r i a t e a m o u n t s of each variable were m i x e d with t h e constant ingredients t o form each of t h e nine diets within each experiment. Analyses of samples of diets from each e x p e r i m e n t for protein c o n t e n t were found within t h e expected range. T h e t u r k e y s were weighed in groups or individually at 2-week intervals. Mortality records were k e p t daily, and average feed c o n s u m p t i o n s were calculated b y 2-week periods. Analyses of variance of average b o d y weight gains, feed c o n s u m p t i o n s , and feed efficiencies by 2- and 4-week periods were calculated. RESULTS AND DISCUSSION Series 1. Results of t h e first four experiments are presented in Table 3. Plots of t h e b o d y weights of t h e t u r k e y s on levels of added m e t h i o n i n e and o n t o t a l sulfur amino acids in
TABLE 2. Assumed composition of feed ingredients and calculated nutrient content of diets without added methionine Protein
Methionine
Cystine
TSAA a
(%)
(%)
(%)
(%)
3,307 7,005
9
.18
.16
.34
2,469 1,914 2,447
49 50 27
.72 .67 .60
.73 .35 .40
1.45 1.02 1.00
3,185 3,122 3,060 3,248 3,185 3,122
18 21 24 15 18 21
.297 .338 .379 .257 .297 .338
.276 .318 .361 .233 .276 .318
Metabolizable energy (kcal/kg) Ingredient Ground yellow corn Hydrolyzed animal and vegetable fat Dehulled soybean meal Meat and bone scraps Corn distillers dried grain with solubles Experiment number 1 through 4 5 through 8
Total sulfur amino acids.
.573 .656 .740 .490 .573 .656
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a Contained manganous oxide, zinc oxide, ferrous carbonate, ferrous sulfate, copper oxide, calcium iodate, cobalt carbonate, and calcium carbonate, and supplied the following in milligrams per kilogram of diet: manganese, 60; zinc, 60; iron, 20; copper, 2.5; iodine, 1 ;and cobalt, .225.
1269
POTTER AND SHELTON
1270
TABLE 3. Body weight gains, feed consumptions, and feed efficiencies of turkeys between 8 and 12 weeks of age (Series 1) Added methionine (%)
Protein 0
(%)
.4
Average
1.438 1.536 1.593 1.523
1.403 1.610 1.616 1.543
1.355 1.507 1.584
3.902 3.968 4.039 3.970
3.902 4.023 4.004 3.976
3.838 3.941 4.055
.2 •
1.224 1.374 1.544 1.381
18 21 24 Average
3.709 3.831 4.121 3.887 .3297 .3584 .3744 .3541
18 21 24 Average
.3681 .3872 .3940 .3831
.3578 .3984 .4021 .3861
.3519 .3813 .3902
Each value is the average of eight values representing the turkeys in four pens of males and four pens of females. Differences required for significance (P<.05) between any two values are .105 kg for body weight gain, .166 kg for feed consumption, and .0197 for feed efficiency. Body weight gain divided by feed consumption.
t h e diets at each level of protein are presented in Figure 1. Analyses of variance of t h e d a t a for b o d y weight gains, feed c o n s u m p t i o n s , and feed efficiencies are presented in Table 4. By increasing t h e p r o t e i n c o n t e n t of t h e diets from 18 to 21 and from 21 to 2 4 % during t h e period b e t w e e n 8 and 12 weeks of age, b o d y weight gains increased 11.2 and 5 . 1 % , feed c o n s u m p t i o n increased 2.7 and 2.9%, and feed efficiencies increased 8.4 and 2 . 3 % , respectively. Differences of 4 . 1 , 2.4, and 3.0% in average b o d y weight gains, feed c o n s u m p -
<9
* 1.7 z
<
^—3Z*
° 1.6 WEIGt
1-
•
/
18 U v/^^ £ / Su
•
/
£ ,, / ADDED METHIONINE,%
.5 .6 .7 .8 .9 1.0 I.I TOTAL SULFUR AMINO ACIDS, %
FIG. 1. Plot of 8- to 12-week body weight gain in kilograms on percent added methionine or percent total sulfur amino acids in the diet.
tions, and feed efficiencies, respectively, for these comparisons were required for significance (P<.05). By adding m e t h i o n i n e to t h e diets at t h e .2 and .4% levels, b o d y weight gains were increased 10.3 and 11.7% ( P < . 0 0 1 ) , respectively. Feed c o n s u m p t i o n s were increased slightly but n o t significantly ( P > . 0 5 ) b y these additions (2.1 and 2 . 3 % , respectively). Feed efficiencies were increased 8.2 and 9.0% ( P < . 0 0 1 ) , respectively. T h e interaction effects of m e t h i o n i n e x protein were small and significant only in t h e feed c o n s u m p t i o n m e a s u r e m e n t s (Table 4). Based u p o n t h e plot of 8- t o 12-week b o d y weight gains (Figure 1), t h e addition of .2% added m e t h i o n i n e t o t h e 18% protein diet significantly increased b o d y weight gains 17.5%, b u t t h e addition of .4% m e t h i o n i n e failed to increase b o d y weight gains further. It is postulated, therefore, t h a t o t h e r amino acids b e c o m e limiting in t h e 18% protein diet during this age period. F r o m t h e plots of t h e b o d y weight gains on total sulfur amino acids in t h e diet (Fig. 1), t h e b o d y weight gains of t u r k e y s during this period appear to be a function of t h e total sulfur amino acids in t h e diet, with t h e exception of t h e diet containing 18% protein and .4% added
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18 21 24 Average
a
METHIONINE AND PROTEIN REQUIREMENT OF TURKEYS
1271
TABLE 4. Analyses of variance of body ;weight gains, feed consumptions, and feed efficiencies of turkeys between 8 and 12 weeks of age (Series 1) Mean squares Degrees of freedom
Source
Diet Protein Methionine Methionine X Protein Sex
Feed consumptions
Feed efficiencies
X 10~ 4
X 10~"
X 10~ 6
1,398*** 3,260*** 1,879***
1,223*** 2,801*** 603
4,461*** 9,644* ** 7,476***
30,702***
744* 127,899***
10,279***
74 135 25 68
184 125 78 267
229 330 202 191
227
3,355*** 282 110 150 69
25,848*** 303 272 364 181
361
9,301*** 1,964** 384 444 325
P<-05.
** P<.01. * ** P<.001.
methionine. However, considering only diets containing 0 and .2% added methionine, it appears that the increased body weight gain was greater from protein than expected from its sulfur amino acid contribution when compared to the increased body weight gain from added methionine per se. Based on multiple regressions of 8- to 10-week (YO, 10- to 12-week (Y 2 ), and 8- to 12-week (Y 3 ) body weight gain in kilograms on percent added methionine (X!) and percent protein (X 2 ) in the diets, using only the diets containing 0 and .2% added methionine, the following equations were obtained: Y, = .186 + .263 X! + .0218 X 2 Y 2 = .365 + .446 X! + .0177 X 2 Y 3 = .551 + .710X! + .0395 X 2 By dividing the value for b 2 by the value for b ! , the growth promoting effects of protein in comparison to that from methionine were 8.3, 4.0, and 5.6% from the respective three equations. The growth promoting effect of protein was expected to be 1.35 or 2.77% of that from added methionine if methionine or total sulfur amino acids, respectively, was the limiting
nutrient. Because the b 2 to b t ratios are significantly larger than expected, it is possible that the sulfur amino acid content of dehulled soybean meal was underestimated or that the dehulled soybean meal is contributing another growth promoting compound. If a regression line is calculated from the 8to 12-week body weight gains in kilograms on total sulfur amino acids in percent of the diet using only the diets containing 0 and .2% added methionine, the following equation is obtained: Y = .748 + .926X Using the diets containing 21 and 24% protein and .4% added methionine as providing the optimum body weight gain (Y = 1.613 kg), the total sulfur amino acid requirement of turkeys between 8 and 12 weeks of age was .93% or 3.04 g/Mcal ME. These values differ from .75% or 2.50 g/Mcal ME as estimated by the NRC (1977). Series 2. The results from the second series of four experiments are presented in Table 5. Plots of body weights of the turkeys on levels of added methionine and on total sulfur amino acids in the diets at each level of protein are presented in Figure 2. Analyses of variance of the data for body weight gains, feed consump-
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Sex X Diet Sex X Protein Sex X Methionine Sex X Methionine X Protein Experiment Experiment X Sex Error Experiment X Diet Experiment X Diet X Sex
8 2 2 4 1 8 2 2 4 3 3 48 24 24
Body weight gains
POTTER AND SHELTON
1272
TABLE 5. Body weight gains, feed consumptions, and feed efficiencies of turkeys between 12 and 16 weeks of age (Series 2) Added methionine (%)
(%)
0
.2
.4
Average
15 18 21 Average
1.359 a 1.559 1.680 1.533
1.400 1.646 1.713 1.587
1.381 1.624 1.699 1.568
1.380 1.610 1.697
15 18 21 Average
5.251 5.505 5.751 5.502
5.250 5.570 5.534 5.451
5.304 5.555 5.560 5.473
5.268 5.543 5.615
Feed c
.2647 .2923 .3067 .2879
.2584 .2893 .3026 .2834
.2601 .2873 .2991
Each value is the average of eight values representing the turkeys in four pens of males and four pens of females. Differences required for significance (P<.05) between any two values are .116 kg for body weight gain, .224 kg for feed consumption, and .0145 for feed efficiency. Body weight gain divided by feed consumption.
tions, and feed efficiencies are presented in Table 6. Body weight gains were increased 16.7 and 5.4% by increasing the protein level of the diet from 15 to 18% and from 18 to 21%, respectively, during the 12- to 16-week period. Accompanying increases in feed consumption of 5.2 and 1.3% and in feed efficiency of 10.5 and 4.1%, respectively, were observed. Differences of 4.3, 2.4, and 3.0% in average body weight gains, feed consumptions, and feed
~
0 .2 .4 ADDED METHIONINES
.4 .5 .6 .7 .8 .9 1.0 I.I TOTAL SULFUR AMINO ACIDS, 1.
FIG. 2. Plot of 12- to 16-week body weight gain in kilograms on percent added methionine or percent total sulfur amino acids in the diet.
efficiencies, respectively, for the protein comparisons were necessary for significance. Body weight gains and feed consumptions were not significantly affected by the addition of methionine to the diets. Feed efficiency was increased 4.6% (P<.05) by the addition of .2% methionine to the diets. Based on a plot of the body weight gains on total sulfur amino acids (Fig. 2), one or more amino acids other than methionine and cystine appear limiting in the 15 and 18% protein diets. A requirement for total sulfur amino acids can not be precisely measured from the data in this series of experiments but appears to be about .75% or 2.40 g/Mcal ME compared to .65% or 2.16 g/Mcal ME as estimated by the NRC (1977). An interaction of protein x sex was also observed in this series (Table 6). The increases in body weight gain from increasing the protein content of the diet from 15 to 18% and from 18 to 21% were 21.1 and 5.8% for males in contrast to 10.4 and 4.8% for females, respectively. The body weight gains of the male turkeys fed the 15, 18, and 21% protein diets from 14 to 16 weeks of age were .869, 1.004, and 1.061 kg in contrast to .572, .583 and .579 kg for female turkeys, respectively. This lack of
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.2573 .2803 .2881 .2752
15 18 21 Average
METHIONINE AND PROTEIN REQUIREMENT OF TURKEYS
1273
TABLE 6. Analysis of variance of body weight gains, feed consumptions, and feed efficiencies of turkeys between 12 and 16 weeks of age (Series 2) Mean squares Degrees of freedom
Source
8 2 2 4 1 8 2 2 4 3 3 48 24 24
Feed consumptions
Feed efficiencies
X 10~"
X 10""
X 10~6
1,667*** 6,445*** 181 21 74,080*** 366 1,290*** 21 76 9,074*** 692** 134 184 84
2,330*** 8,029*** 156 568 379,306*** 306 554 148 262 24,535*** 4,250*** 495 608 382
2,703*** 9,605*** 993* 106 30,160*** 461 1,710*** 19 57 29,070*** 141 207 293 122
P<.05.
** P<.01. ** *
P<.001.
increase in b o d y weight gains of females for added protein from 14 t o 16 weeks was responsible for t h e interaction of p r o t e i n X sex in t h e b o d y weight gains (Table 6 ) . Females were n o t gaining weight as rapidly during t h e 14- to
16-week period as in t h e 1 2 - t o 14-week period (.579 as compared to . 6 6 4 kg, respectively). As a result, t h e apparent protein requirement for females was n o t as great as for males during this period.
TABLE 7. Percentage increase in body weight gain from adding protein to the diet3 Age (weeks) in diet (%)
Sex
0-2
2-4
4-6
6-8 • Increase
30 over 27
27 over 24
24 over 21
21 over 18
18 over 15
Males Females Both Males Females Both Males Females Both Males Females Both Males Females Both
3.7 3.1 3.2 8.4 15.8 11.9 15.2 12.6 13.8
7.9 4.8 6.4 14.6 17.3 15.8 26.2 20.5 23.6
8.1 5.6 7.0 12.8 12.2 12.5 20.7 25.2 22.7
3.7 3.8 3.8 15.0 9.9 12.7 17.0 23.7 20.0
8-10
10-12
12-14
14-16
6.1 9.5 7.5 27.5 18.9 23.8
5.6 -.7 3.3 15.5 1.8 10.1
,
7.1 5.9 6.6 12.1 14.0 12.9
5.9 1.3 3.9 9.6 9.8 9.7
Includes data to eight weeks of age from one previous study (Potter and Shelton, 1979).
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Diet Protein Methionine Methionine X Protein Sex Sex X Diet Sex X Protein Sex X Methionine Sex X Methionine X Protein Experiment E x p e r i m e n t X Sex Error E x p e r i m e n t X Diet E x p e r i m e n t X Diet X Sex
Body weight gains
POTTER AND SHELTON
1274
in Table 7. These d a t a for male and female t u r k e y s are presented graphically in Figures 3 and 4. By calculating multiple regressions of percent increase in average b o d y weight gain of males ( Y , ) or females ( Y 2 ) on age of t u r k e y s in weeks ( X i ) and percent protein in diet ( X 2 ) , t h e following e q u a t i o n s were o b t a i n e d :
Yi = 71.5 - 1.407 Xi - 2.378 X 2 Y 2 = 79.3 - 2.040 Xi - 2.602 X 2
Protein Requirement of Medium White Turkeys at Various Ages. T h e percentage increase in b o d y weight gain from adding protein t o diets of male and female t u r k e y s by 2-week periods o b t a i n e d in a previous s t u d y to 8 weeks of age (Potter and Shelton, 1979) and in this study from 8 to 16 weeks of age are presented
ACKNOWLEDGMENTS Vitamins were supplied by Agricultural Processing Corporation, Salem, VA, and by Hoffmann-LaRoche, Inc., Nutley, NJ.
REFERENCES
2
4
6
8
10
12
AGE AT END OF P E R I O D ,
14
16
WEEKS
FIG. 4. Plot of percent increase in body weight gain from increasing the protein content of the diet on age of female turkeys by 2-week periods.
Murillo, M. G., and L. S. Jensen, 1976. Methionine requirement of developing turkeys from 8-12 weeks of age. Poultry Sci. 55:1414—1418. National Research Council, 1977. Nutrient requirements of domestic animals. Number 1. Nutrient requirements of Poultry. Nat. Acad. Sci., Washington, DC. Potter, L. M., and J. R. Shelton, 1979. Methionine and protein requirements of young turkeys. Poultry Sci. 58:609-615.
Downloaded from http://ps.oxfordjournals.org/ at Simon Fraser University on June 1, 2015
AGE AT END OF PERIOD, WEEKS FIG. 3. Plot of percent increase in body weight gain from increasing the protein content of the diet on age of male turkeys by 2-week periods.
T h e mid-point of t h e range in age and t h e lower protein level given in Table 7 were used in t h e regression. Where t h e p e r c e n t increase in b o d y weight gain of t u r k e y s from feeding a given level of protein over a lower level becomes zero, t h e lower level of protein is considered t h e protein requirement at t h e stated age. T h e p r o t e i n requirement of male turkeys at t h e older ages is significantly ( P < . 0 5 ) higher t h a n of female t u r k e y s . T h e d a t a of Series 2 and also the pooled d a t a r e p o r t e d in Table 7 and Figures 3 and 4 s u p p o r t this conclusion. Based u p o n these multiple regressions, protein requirements for M e d i u m White male t u r k e y s at 0, 4, 8, 12, and 16 weeks are 3 0 . 1 , 27.7, 2 5 . 3 , 2 3 . 0 , and 20.6%, respectively, and for female t u r k e y s 30.5, 2 7 . 3 , 2 4 . 2 , 2 1 . 1 , and 17.9%, respectively. Within the limits of these studies, t h e protein requirement of Medium White t u r k e y s is a b o u t 30.3% at one day of age and decreases .61 and .78 percentage units per week for males and females, respectively.