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Lysine and Protein Requirements of Bronze Turkeys1
884
D. K. MCLOUGHLIN, E. E. WEHR AND R. RUBIN
REFERENCES Barber, C. W., 1955. Nicarbazin in the prevention of coccidiosis in chickens. Cornell Vet. 45: 360-366. Brant, A. W., A. W. Otte and K. H. Norris, 1951. Recommended standards for scoring and measuring opened egg quality. Food Tech. 9: 356361.
Brant, A. W., and H. L. Shrader, 1952. How to measure egg I. Q. (Interior quality). U. S. Dept. Agr., PA-202, 11 pp. Clark, I., R. F. Geoffroy, J. L. Gilfillan and C. C. Porter, 1956. Absorption and elimination of carbon-14-labelled Nicarbazin by chickens. Proc. Soc. Exp. Biol. Med. 9 1 : 4-6. McClary, C. F., 1955. The restriction of ooporphyrin deposition on egg shells by drug feeding. Poultry Sci. 34: 1164-1165. Ott, W. H., S. Kuna, C. C. Porter, A. C. Cuckler and D. E. Fogg, 1955. Biological studies on nicarbazin, a new anticoccidial agent. Poultry Sci. 34: 1215. Porter, C. C , and J. F. Gilfillan, 1955. The absorption and excretion of orally administered nicarbazin by chickens. Poultry Sci. 34: 9951001. Rubin, R., D. K. McLoughlin, L. C. Costello and E. E. Wehr, 1956. The efficacy of Nicarbazin as a prophylactic drug in cecal coccidiosis of chickens. Poultry Sci. 35: 856-860. Snyder, E. S., 1956. Affects egg quality. Nicarbazin excellent for growers but not for layers. Canadian Poultry Review, 80 ( 9 ) : 13.
Lysine and Protein Requirements of Bronze Turkeys 1 S. L. BALLOUN AND R. E. PHILLIPS Department of Poultry Husbandry, Iowa State College, Ames, Iowa (Received for publication March 16, 1957)
ALMQUIST (1952) reviewed the litera-**• ture on the lysine requirement of poults to four weeks of age and concluded that, based on research from a number of sources, about 5.5 percent of the protein should be lysine. This recommendation seemed to be based on a 24 percent protein diet containing 1.3 percent lysine. However, one reference was quoted in which 1.46 percent lysine in a 28 percent protein diet gave best results with poults to 4 weeks of age. Kratzer, Davis and Marshall (1956) 'Journal Paper No. J-3160 of the Iowa Agricultural Experiment Station, Ames, Iowa. Project No. 1327.
have concluded that the lysine requirement as a percent of the protein is approximately 4.75 percent for poults from hatching to 4 weeks and then decreases to about 4 percent. They indicate that the protein requirement is about 28 percent initially, dropping to 23 percent by 6 weeks of age, 20 percent at 8 weeks, 15 percent at 16 weeks and 13.5 percent at 20 weeks. Ferguson et al. (1956) obtained the best general performance with eight-week-old poults fed a 24.8 percent protein diet supplemented with methionine. Little, if any, benefit was obtained from lysine supplementation in their trials at any protein
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stead of brown eggs. The treated hens continued to lay white eggs for two days following the withdrawal of the drug, after which the brown coloration began gradually to return. The number of eggs produced by the hens during the second week of treatment was only half that produced by controls. This difference in egg production was maintained until more than a week after nicarbazin was discontinued. No significant differences were observed in weight, shell thickness, or interior quality of eggs produced by treated and untreated hens.
LYSINE AND PROTEIN REQUIREMENTS OF TURKEYS
Ferguson et al. (1956) obtained results similar to those of Klain et al. In their trials the growth obtained with poults fed 21.7 percent protein diets supplemented with amino acids did not equal that obtained with 28.6 percent protein practical diets. In the reported trials, Baldini et al. used Jersey Buff poults and a simple corn-soybean meal type diet. Klain et al. and Ferguson et al. fed diets containing considerable animal protein products to Broad Breasted Bronze poults. Fisher et al. used Jersey Buff poults. Their low-protein diets were essentially the same as those fed by Baldini et al., but their 28 percent protein
diet contained 12 percent fish meal, 5 percent meat scraps and 5 percent dried brewers' yeasts. In all of these trials the productive energy level of the diets was reduced considerably as the protein level was increased. Type of diet, variety and sex of poults, energy level of the diet, and rate of growth obtained are no doubt important factors in determining the responses to increased protein level of the diet and amino acid supplementation. The investigations to be reported here were conducted with Broad Breasted Bronze poults fed practical diets. EXPERIMENTAL
Broad Breasted Bronze poults were housed in conventional chick starter batteries to three weeks of age, in intermediate batteries without supplementary heat from three weeks to six weeks, and in floor pens with attached sun porches, thereafter. Six-hundred seventy-two poults were randomly distributed into 48 experimental pens with four replicate pens fed each test diet for the first six weeks' period. Six protein levels, varying from 21 to 31 percent at 2 percent intervals, were fed with and without 0.1 percent added L-lysine HC11 (0.076% L-lysine) in this period. At six weeks of age, the poults were redistributed under a controlled randomization plan so that each of the 24 experimental pens in the 6 to 12 weeks' period contained two poults from each of the twelve original experimental treatments. In the second six weeks' period, six protein levels, varying from 15 to 25 percent at 2 percent intervals were fed with and without lysine to duplicate pens of 24 poults per pen. 1
95% L-lysine HC1 was used as the source of supplemental lysine in all cases. This was obtained through the courtesy of E. I. DuPont de Nemours and Co., Wilmington, Delaware.
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level. Essentially equal growth was obtained with an unsupplemented 28.6 percent protein diet as with the 24.8 percent diet supplemented with methionine or tryptophan. Recently, several papers have been published which indicate that excellent results may be obtained with diets containing as little as 20 percent protein if the diet is supplemented with lysine. Fisher, Dowling and Maddy (1956) have reported that lysine and methionine hydroxy analoguesupplemented low protein diets resulted in poult weight gains superior to those produced by a practical high-protein diet. In fact, in one case they report superior growth to six weeks for poults fed an amino acid-supplemented simple 20 percent protein diet as compared to poults fed a 28 percent protein diet supplemented with amino acids, fish meal, meat scraps and dried brewers' yeasts. These findings support the reports of Baldini et al. (1954). Klain, Hill and Slinger (1954), however, have shown that under their conditions growth was superior for poults fed diets containing 25.5 and 28 percent protein compared to a 21.8 percent protein diet supplemented with methionine and lysine.
885
886
S. L. BALLOUN AND R. E. PHILLIPS
TABLE 1.—Composition of diets
Ingredient Gr. yellow corn Soybean oil meal (44% protein) Wheat bran Wheat middlings Fish meal (65% protein) Meat & bone scrap (50% protein) Dehyd. alf. meal Dried whey Dr. Br. yeast St. bone meal Gr. oyster shell Iodized salt Mn sulphate (tech.) Pre-mix* Calculated Productive Energy (C/lb.)
0-6 wks. (21%)
6-12 wks. (15%)
12-24 wks. (10%)
44.0
59.0
78.0
15.0 5.0 10.0 5.0
0.0 5.0 10.0 5.0
0.0
4.0 5.0 5.0 2.0 1.5 2.0 0.45 0.05 1.00
4.0 5.0 5.0 2.0 1.5 2.0 0.45 0.05 1.00
—
10.0
— 2.5 2.5
— —
4.0 1.5 0.45 0.05 1.00
100.0
100.0
100.0
850
902
970
* Provides per pound of diet (mg./pound): riboflavin 2, pantothenic acid 4, niacin 10, choline 400, vitamin B12 0.006, and vitamin E 5 IU, vitamin D3 900 ICU, vitamin A 3300 IU per pound, penicillin 4 and terramycin 10 mg. per pound and methionine 0.05%.
nique is similar to that employed by previous investigators in this field, it may be criticized in that as the protein level is increased by the substitution of soybean oil meal for corn, the energy level of the diet is decreased. The calculated productive energy values for the three low protein diets are given in Table 1. In each period, each 2 percent increase in protein resulted in a decrease in energy of approximately 18 productive Calories per pound of diet. RESULTS AND DISCUSSION 1 Day to Six Weeks. The results of the first period are shown in Table 2. The addition of 0.076 percent L-lysine markedly increased the growth of poults fed a low protein diet. This is especially evident at the lowest protein level. It is also evident that the males responded more to lysine additions than did females. The protein (and lysine) requirement of the male was found to be higher than that of the female. Without supplemental lysine, maximum growth of the males was obtained when the diet contained 31 percent protein, while females grew as well on 27 percent as on 29 or 31 percent protein diets. No significant response to added lysine was obtained wtih either sex on the high protein diets, but the response to lysine supplementation increased as the protein content of the diet was decreased. The general effect, for each sex, was that the addition of lysine decreased the protein requirement for maximum growth by at least two percentage units. In no case, however, did the growth obtained to six weeks with a lysine-supplemented 21 or 23 percent protein diet equal that obtained with the higher protein diets without added lysine. Actually, the poults fed the 21 percent diet with added lysine weighed approximately 9 percent less than poults fed the 27 percent protein diet without added lysine.
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At 12 weeks, the poults were again rerandomized into 24 new experimental groups with the same number of poults from each previous dietary treatment assigned to each new experimental pen. Six protein levels, varying from 10 to 20 percent at 2 percent intervals, were fed during the 12 to 24 week period with four experimental pens per treatment. The lysinesupplementation portion of the experiment was discontinued at 12 weeks. Poults were weighed individually and feed consumption was calculated at three week intervals to 12 weeks of age and each four weeks thereafter. The basal diets for the lowest protein level ration in each period are given in Table 1. Variations in protein level were obtained by varying the corn and soybean oil meal. No attempt was made to maintain the same energy level in the diets of differing protein levels. Although this tech-
LYSINE AND PROTEIN REQUIREMENTS OF TURKEYS
TABLE 2.—Effect
887
of protein level and added lysine on weight and feed efficiency of poults 0-6 weeks1
Without added lysine
With added lysinef
Actual analyses (%)* Weight (grams) Protein
M 21.2 23.3 25.2 27.2 29.3 31.3
1.12 1.27 1.41 1.55 1.70 1.85
Weight (grams) - Feed/gain
- Feed/gain
Lysine 1023 1139 1186 1196 1183 1224
Av. 914 1006 1026 1076 1061 1077
968 1072 1106 1136 1122 1151
M 2.20 2.18 2.17 2.13 2.19 2.27
1116 1160 1237 1234 1221 1236
Av.
971 1026 1101 1101 1067 1058
1044 1093 1169 1167 1144 1147
2.20 2.09 2.05 2.17 2.20 2.22
In this respect, the results reported here differ from those of Baldini et al. (1954) and Fisher et al. (1956), but support the results reported by Klain, Hill and Slinger (1954) and Ferguson et al. (1956). It should be observed that Klain et al. and Ferguson et al. used Bronze poults and that the rate of growth was comparable to that achieved in the experiments reported here. Baldini et al. (1954) and Fisher et al. (1956) used Jersey Buff poults and it may well be that the slower gains of the poults in their experiments reflect a lower lysine and protein requirement for this variety. In the experiments reported here, lysine supplementation increased growth appreciably only when the diet contained less than 1.55 percent lysine. The addition of 0.076 percent L-lysine to the 27 percent protein diet (1.55 percent lysine) increased poult growth by only 3 percent, and lysine additions to the 29 percent protein diet (1.70 percent lysine) produced no appreciable improvement in growth. Among the lysinesupplemented diets, maximum growth was obtained with each sex on the 25 percent protein diet containing a total (bound plus added free lysine) of 1.49 percent lysine. Increasing the protein in this case to 27 percent (total lysine 1.63 percent) did not increase growth. These results indicate a
lysine requirement of at least 1.49 percent for a 25 percent protein diet containing 814 Calories and about 1.55 percent for a 27 percent protein diet containing 796 Calories productive energy per pound. This reflects a slightly higher lysine requirement than that reported by Almquist (1952) and considerably above that reported by Kratzer, Davis and Marshall (1956). It should be noted, however, that the conclusion of Kratzer et al. (1956) regarding the lysine requirement of the poult to four weeks of age was based mainly on a previously published paper by the same authors (Kratzer et al., 1955), and that in this report 13.6 percent of the poults exhibited white barring at four weeks even when fed a 26 percent protein ration containing 1.39 percent lysine (5.3 percent lysine of protein). An analysis of the data on feed required per pound of gain in the 0-6 weeks' period revealed no significant differences among lots fed lysine-supplemented and unsupplemented diets. Although lysine apparently improved the feed efficiency with 23 or 25 percent protein diets, no improvement was obtained by supplementing the 21 percent protein diet or those diets containing 2 7 or 29 percent protein. It must be concluded, therefore, that the variation in such factors
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1 Four pens of 14 Bronze poults each per experimental treatment. * Of diet before lysine supplementation. Protein by Kjeldahl analysis; lysine determined by microbiological assay. f L-lysine HC1 9 5 % equiv. to 0.076% L-lysine.
S. L. BALLOUN AND R. E. PHILLIPS TABLE 3.—Effect of protein level and added lysine on weight gains ant efficiency of poults in the 6-12 weeks' period1 Without added ly jne
Calculateci analyses Protein
Lysine
With added lysine*
Weight (grams)
Weight (grams) - Feed/gain
- Feed/gain
(%)
(%)
M
F
Av.
15 17 19 21 23 25
0.68 0.80 0.93 1.07 1.21 1.34
1285 1807 2246 2508 2710 2593
1043 1455 1802 2009 2064 2091
1164 1631 2024 2258 2387 2342
3.76 3.17 2.84 2.66 2.65 2.58
M
F
Av.
1564 2092 2388 2620 2708 2627
1252 1657 1852 2054 2010 2136
1408 1875 2120 2337 2359 2381
3.50 2.86 2.73 2.66 2.66 2.62
as feed wastage and individual variations made it impossible to measure precisely the feed utilization differences due to lysine supplementation in this phase of the experiment. 6 to 12 weeks. As shown in Table 3, the protein requirement for maximum growth in the 6-12 week period was not over 23 percent for males and 21 percent for females without lysine supplementation since growth rates reached a practical plateau at these levels. When the diets were supplemented with
lysine, there was an appreciable improvement in both feed conversion and in weight gains for the lower protein diets. No further improvements in weight gains or feed conversion were obtained by increasing the protein above 21 percent in a lysine-supplemented diet. Figure 1 shows graphically the effect of lysine supplementation at the various protein levels in the 6 to 12 weeks' period. The general effect of adding lysine was to reduce the protein required for maximum growth and feed conversion approximately
3000]
15
17
19 21 PROTEIN IN RATION
23
25
FIG. 1. Effect of protein level and added lysine on poult gains and feed efficiency in the 6-12 week period.
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Duplicate pens of 24 poults each per experimental treatment. ' L-lysine HC1 9 5 % equiv. to 0.076% L-lysine.
•
LYSINE AND PROTEIN REQUIREMENTS OF TURKEYS
Since toms and hens were housed together, feed conversion could not be cal^ k u l a t e d for the separate sexes. However, for ^ ^ h e mixed-sex pens, a significant improvement in feed efficiency was obtained by adding lysine to diets containing 19 percent or less protein in the 6-12 week period (Figure 1). No improvement in feed efficiency was realized by increasing the protein of the diet above 21 percent. These results verify the observations of Yacowitz et al. (1956) as to protein requirements of turkeys at this age. These authors did not use diets with less than 20 percent protein, but they showed that no improvement was obtained by using more than 20 percent protein in the diets of turkeys between 9 and 16 weeks. The increased response of males in our trials to 23 percent protein diets as compared to 21 percent was probably due to the younger age (6-12 weeks). These results also agree with those of Kratzer, Davis and Marshall (1956) as to protein requirements, but indicate a con-
•
siderably higher lysine requirement for poults at this age. Kratzer et al. concluded that lysine requirement is approximately 4.75 percent of the protein to four weeks of age and then drops to approximately 4.00. In the trials reported here, growth of males in the 6-12 weeks' period was improved nearly 22 percent by lysine supplementation when the diet contained 15 percent protein and approximately 5 percent of this was lysine. Even with a diet containing 19 percent protein and 0.93 percent lysine significant growth response was obtained with males by supplementing the diet with lysine. The results of Kratzer et al. would indicate that one should not expect lysine supplementation to improve a diet containing this much lysine. It must be remembered, however, that Kratzer et al indicate average requirements of males and females, but even for a mixed flock the results presented here indicate that the lysine requirement is at least 5 percent of the protein for the rapidly growing poult at 6 weeks of age. 12 to 24 weeks. At 12 weeks of age the turkeys were re-randomized into new experimental lots as described previously. Lysinesupplementation was discontinued at this time and emphasis was placed on determining optimum protein levels for maximum gain, feed efficiency and least-cost. Six protein levels ranging from 10 to 20 percent were fed in this period with 4 replicate lots per each experimental diet. The results otbtained in the period are shown in Table 4. The requirement for maximum growth of males was 20 and for females 18 percent protein during the 1216 week period. As the birds grew older, the protein requirement decreased rapidly so that by the 20-24 week period females fed 12 percent protein and males fed 14 percent protein were rapidly making up earlier deficiencies in gains and were approaching the weights of birds fed higher
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2 percentage units. This figure also illustrates the higher requirement of males for lysine and protein. Growth response to lysine supplementation was obtained with males when the diet contained 21 percent or less protein. With females, the addition of lysine did not improve growth significantly when the diet contained 19 percent or more protein. Calculation of the lysine content of the diets indicates that for males, 1.21 percent lysine was sufficient for maximum growth in a diet containing 23 percent protein and 830 Calories productive energy per pound in this period. For females, since only slight increases in growth resulted from adding lysine to diets containing 19 percent or more protein, 0.93 percent lysine appears sufficient in a diet containing this level of protein and 866 Calories productive energy per pound.
889
890
S. L. BALLOUN AND R. E. PHILLIPS TABLE 4.—Effect
16-20 wks.
12-16 wks. Protein in ration
(%) 10 12 14 16 18 20
conversion of poults
of protein level on growth m in the period, 12-24 weeks1
20-24 wks. Gain
Gain
Gain M
F
Av.
0.57 3.16 4.16 5.05 5.41 5.72
0.58 2.48 3.24 3.70 4.03 4.08
0.57 2.82 3.70 4.37 4.72 4.90
15.7 4.5 3.9 3.6 3.4 3.3
F/g
F/g
F/g M
F
Av.
1.49 3.82 4.95 5.63 5.54 5.84
1.51 3.20 3.65 3.48 3.53 3.45
1.50 3.51 4.30 4.56 4.54 4.65
8.7 5.3 4.7 4.8 5.2 5.0
M
F
Av.
2.95 5.66 6.05 5.20 5.25 4.68
2.53 3.53 3.06 2.76 2.64 2.67
2.74 4.60 4.56 3.98 3.94 3.67
7.2 6.0 6.6 7.8 8.4 8.8
protein levels throughout the 12-24 weeks' period. While the 20-24 weeks' data cannot be statistically evaluated alone, evidence seems clear that at this age, a 12 percent protein diet will produce satisfactory gains and feed efficiency. The extreme deficiency of the 10 percent protein ration caused a severe retardment of development in the 12-16 week period which was not overcome by the 24th week. The possibility remains, however, that very low-protein, high-energy rations (10-12 percent protein) could be successfully fed in a finishing period if the birds had been grown to 20 weeks at a normal rate of gain. Calculations of least-cost rations based on the data obtained in these experiments (Heady et al., 1956; and Balloun et al., 1957) show that for most normal soybean oil meal: corn price ratios, the least-cost ration for any given period is somewhat lower in protein than is required for maximum growth. For example, with a soy bean oil meal: corn price ratio of 1.4 (soybean oil meal $70 per ton and corn $50 per ton) the least-cost ration would have been 24 percent protein in the 0-6 weeks' period while a 2 7 percent protein ration produced maximum gains. For the 6-12 weeks' period, with the same price ratio, the least-cost ration was 21 percent protein while the maximum growth was obtained with a 23 percent protein ration.
SUMMARY
The protein requirement of Broad Breasted Bronze poults was found to be at least 27 percent to six weeks of age. When diets were supplemented with lysine, maximum growth and feed efficiency was obtained with 25 percent protein diets. Added lysine improved growth and feed efficiency in the 0-6 weeks' period when the diet contained less than 1.55 percent lysine. In the 6-12 weeks' period, maximum growth was achieved when the males were fed 23 and the females 21 percent protein. Lysine supplementation reduced this requirement by about 2 percentage units. The protein requirement of the poult at 12 weeks was 20 percent, decreasing rapidly thereafter to about 12 percent at 24 weeks. At all ages, the optimum protein level for best feed efficiency and least-cost was somewhat lower than that for maximum weight gains. REFERENCES Almquist, H. J., 1952. Amino acid requirements of chickens and turkeys—a review. Poultry Sci. 3 1 : 966-981. Baldini, J. T., H. R. Rosenberg and J. Wadell, 1954. The protein requirement of the turkey poult. Poultry Sci. 33: 539-543. Balloun, S. L., G. W. Dean and E. O. Heady, 19S7. Least-cost rations for turkeys. Farm Sci. 11: 433-436. Ferguson, T. M., H. P. Vaught, B. L. Reid and
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Four pens of 24 Bronze poults each per experimental treatment.
LYSINE AND PROTEIN REQUIREMENTS OF TURKEYS
Supplementation of poult diets with lysine. Poultry Sci. 33 : 1280-1282. Kratzer, F. H., P. N. Davis and B. J. Marshall, 1955. Cottonseed meal in rations for starting poults, growing turkeys and turkey breeder hens. Poultry Sci. 34: 462-468. Kratzer, F. H., P. N. Davis and B. J. Marshall, 1956. The protein and lysine requirements of turkeys at various ages. Poultry Sci. 35: 197202. Yacowitz, H., R. D. Carter, J. Wyne and M. G. McCartney, 1956. Effects of varying protein and fat levels in a finishing ration for turkey broilers. Poultry Sci. 35: 227-229.
Mechanisms of Shell Egg Deterioration: Comparisons of Chicken and Duck Eggs 12 MARVIN
B.
R H O D E S AND ROBERT E.
FEENEY
Department of Biochemistry and Nutrition, College of Agriculture, University of Nebraska, Lincoln, Nebraska (Received for publication March 20, 1957)
INTRODUCTION
to a basic understanding ONEof approach biological systems is through a comparative study of the physical and biochemical properties of closely related species. It is the purpose of such studies to utilize the subtle differences provided by nature to determine the relative significances and roles of the individual components of the systems. An attempt has been made to utilize such an approach in the present investigation. A comparative study of certain properties of chicken and duck eggs has been made in order to obtain information basic to the understanding of the causes and mechanisms of the deteriora1
Published with the approval of the Director as Paper 808, Journal Series, Nebraska Agricultural Experiment Station. 2 This work supported in part by RMA funds through the Regional Research Project under the NCM-7 Technical Committee.
tions of quality of chicken eggs during storage. Chicken and duck eggs have been reported to have closely similar compositions. Chemically, they apparently differ primarily in the relative amounts of their various constituents and in minor (but important) differences in the molecular structure of the individual components. Most of the information available on this subject refers to the egg whites. Bain and Deutsch (1947) in an electrophoretic study found important differences in the ovalbumin, conalbumin and lysozyme contents. These differences were confirmed by means of chemical and biochemical analyses by MacDonnell, Ducay, Sugihara and Feeney (1954) who also reported a significant difference in the content of ovomucoid and in the nature of the sulfhydryl groups. In a further study, Sugihara, MacDonnell, Knight and Feeney (1955) found large differences in the contents of virus antihemagglutinin activity
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J. R. Couch, 1956. The effect of amino acid supplements to the diet of Broad Breasted Bronze turkey poults fed various levels of protein and productive energy. Poultry Sci. 35: 1069-1073. Fisher, H., J. Dowling, Jr. and K. H. Maddy, 1956. Low protein diets for turkeys raised under practical conditions. Poultry Sci. 35: 239241. Heady, E. O., S. Balloun and G. W. Dean, 1956. Least-cost rations and optimum marketing weights for turkeys. Iowa Agr. Exp. Sta. Res. Bui. 443. Klain, G. J., D. C. Hill and S. J. Slinger, 1954.
891
D. K. MCLOUGHLIN, E. E. WEHR AND R. RUBIN
REFERENCES Barber, C. W., 1955. Nicarbazin in the prevention of coccidiosis in chickens. Cornell Vet. 45: 360-366. Brant, A. W., A. W. Otte and K. H. Norris, 1951. Recommended standards for scoring and measuring opened egg quality. Food Tech. 9: 356361.
Brant, A. W., and H. L. Shrader, 1952. How to measure egg I. Q. (Interior quality). U. S. Dept. Agr., PA-202, 11 pp. Clark, I., R. F. Geoffroy, J. L. Gilfillan and C. C. Porter, 1956. Absorption and elimination of carbon-14-labelled Nicarbazin by chickens. Proc. Soc. Exp. Biol. Med. 9 1 : 4-6. McClary, C. F., 1955. The restriction of ooporphyrin deposition on egg shells by drug feeding. Poultry Sci. 34: 1164-1165. Ott, W. H., S. Kuna, C. C. Porter, A. C. Cuckler and D. E. Fogg, 1955. Biological studies on nicarbazin, a new anticoccidial agent. Poultry Sci. 34: 1215. Porter, C. C , and J. F. Gilfillan, 1955. The absorption and excretion of orally administered nicarbazin by chickens. Poultry Sci. 34: 9951001. Rubin, R., D. K. McLoughlin, L. C. Costello and E. E. Wehr, 1956. The efficacy of Nicarbazin as a prophylactic drug in cecal coccidiosis of chickens. Poultry Sci. 35: 856-860. Snyder, E. S., 1956. Affects egg quality. Nicarbazin excellent for growers but not for layers. Canadian Poultry Review, 80 ( 9 ) : 13.
Lysine and Protein Requirements of Bronze Turkeys 1 S. L. BALLOUN AND R. E. PHILLIPS Department of Poultry Husbandry, Iowa State College, Ames, Iowa (Received for publication March 16, 1957)
ALMQUIST (1952) reviewed the litera-**• ture on the lysine requirement of poults to four weeks of age and concluded that, based on research from a number of sources, about 5.5 percent of the protein should be lysine. This recommendation seemed to be based on a 24 percent protein diet containing 1.3 percent lysine. However, one reference was quoted in which 1.46 percent lysine in a 28 percent protein diet gave best results with poults to 4 weeks of age. Kratzer, Davis and Marshall (1956) 'Journal Paper No. J-3160 of the Iowa Agricultural Experiment Station, Ames, Iowa. Project No. 1327.
have concluded that the lysine requirement as a percent of the protein is approximately 4.75 percent for poults from hatching to 4 weeks and then decreases to about 4 percent. They indicate that the protein requirement is about 28 percent initially, dropping to 23 percent by 6 weeks of age, 20 percent at 8 weeks, 15 percent at 16 weeks and 13.5 percent at 20 weeks. Ferguson et al. (1956) obtained the best general performance with eight-week-old poults fed a 24.8 percent protein diet supplemented with methionine. Little, if any, benefit was obtained from lysine supplementation in their trials at any protein
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stead of brown eggs. The treated hens continued to lay white eggs for two days following the withdrawal of the drug, after which the brown coloration began gradually to return. The number of eggs produced by the hens during the second week of treatment was only half that produced by controls. This difference in egg production was maintained until more than a week after nicarbazin was discontinued. No significant differences were observed in weight, shell thickness, or interior quality of eggs produced by treated and untreated hens.
LYSINE AND PROTEIN REQUIREMENTS OF TURKEYS
Ferguson et al. (1956) obtained results similar to those of Klain et al. In their trials the growth obtained with poults fed 21.7 percent protein diets supplemented with amino acids did not equal that obtained with 28.6 percent protein practical diets. In the reported trials, Baldini et al. used Jersey Buff poults and a simple corn-soybean meal type diet. Klain et al. and Ferguson et al. fed diets containing considerable animal protein products to Broad Breasted Bronze poults. Fisher et al. used Jersey Buff poults. Their low-protein diets were essentially the same as those fed by Baldini et al., but their 28 percent protein
diet contained 12 percent fish meal, 5 percent meat scraps and 5 percent dried brewers' yeasts. In all of these trials the productive energy level of the diets was reduced considerably as the protein level was increased. Type of diet, variety and sex of poults, energy level of the diet, and rate of growth obtained are no doubt important factors in determining the responses to increased protein level of the diet and amino acid supplementation. The investigations to be reported here were conducted with Broad Breasted Bronze poults fed practical diets. EXPERIMENTAL
Broad Breasted Bronze poults were housed in conventional chick starter batteries to three weeks of age, in intermediate batteries without supplementary heat from three weeks to six weeks, and in floor pens with attached sun porches, thereafter. Six-hundred seventy-two poults were randomly distributed into 48 experimental pens with four replicate pens fed each test diet for the first six weeks' period. Six protein levels, varying from 21 to 31 percent at 2 percent intervals, were fed with and without 0.1 percent added L-lysine HC11 (0.076% L-lysine) in this period. At six weeks of age, the poults were redistributed under a controlled randomization plan so that each of the 24 experimental pens in the 6 to 12 weeks' period contained two poults from each of the twelve original experimental treatments. In the second six weeks' period, six protein levels, varying from 15 to 25 percent at 2 percent intervals were fed with and without lysine to duplicate pens of 24 poults per pen. 1
95% L-lysine HC1 was used as the source of supplemental lysine in all cases. This was obtained through the courtesy of E. I. DuPont de Nemours and Co., Wilmington, Delaware.
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level. Essentially equal growth was obtained with an unsupplemented 28.6 percent protein diet as with the 24.8 percent diet supplemented with methionine or tryptophan. Recently, several papers have been published which indicate that excellent results may be obtained with diets containing as little as 20 percent protein if the diet is supplemented with lysine. Fisher, Dowling and Maddy (1956) have reported that lysine and methionine hydroxy analoguesupplemented low protein diets resulted in poult weight gains superior to those produced by a practical high-protein diet. In fact, in one case they report superior growth to six weeks for poults fed an amino acid-supplemented simple 20 percent protein diet as compared to poults fed a 28 percent protein diet supplemented with amino acids, fish meal, meat scraps and dried brewers' yeasts. These findings support the reports of Baldini et al. (1954). Klain, Hill and Slinger (1954), however, have shown that under their conditions growth was superior for poults fed diets containing 25.5 and 28 percent protein compared to a 21.8 percent protein diet supplemented with methionine and lysine.
885
886
S. L. BALLOUN AND R. E. PHILLIPS
TABLE 1.—Composition of diets
Ingredient Gr. yellow corn Soybean oil meal (44% protein) Wheat bran Wheat middlings Fish meal (65% protein) Meat & bone scrap (50% protein) Dehyd. alf. meal Dried whey Dr. Br. yeast St. bone meal Gr. oyster shell Iodized salt Mn sulphate (tech.) Pre-mix* Calculated Productive Energy (C/lb.)
0-6 wks. (21%)
6-12 wks. (15%)
12-24 wks. (10%)
44.0
59.0
78.0
15.0 5.0 10.0 5.0
0.0 5.0 10.0 5.0
0.0
4.0 5.0 5.0 2.0 1.5 2.0 0.45 0.05 1.00
4.0 5.0 5.0 2.0 1.5 2.0 0.45 0.05 1.00
—
10.0
— 2.5 2.5
— —
4.0 1.5 0.45 0.05 1.00
100.0
100.0
100.0
850
902
970
* Provides per pound of diet (mg./pound): riboflavin 2, pantothenic acid 4, niacin 10, choline 400, vitamin B12 0.006, and vitamin E 5 IU, vitamin D3 900 ICU, vitamin A 3300 IU per pound, penicillin 4 and terramycin 10 mg. per pound and methionine 0.05%.
nique is similar to that employed by previous investigators in this field, it may be criticized in that as the protein level is increased by the substitution of soybean oil meal for corn, the energy level of the diet is decreased. The calculated productive energy values for the three low protein diets are given in Table 1. In each period, each 2 percent increase in protein resulted in a decrease in energy of approximately 18 productive Calories per pound of diet. RESULTS AND DISCUSSION 1 Day to Six Weeks. The results of the first period are shown in Table 2. The addition of 0.076 percent L-lysine markedly increased the growth of poults fed a low protein diet. This is especially evident at the lowest protein level. It is also evident that the males responded more to lysine additions than did females. The protein (and lysine) requirement of the male was found to be higher than that of the female. Without supplemental lysine, maximum growth of the males was obtained when the diet contained 31 percent protein, while females grew as well on 27 percent as on 29 or 31 percent protein diets. No significant response to added lysine was obtained wtih either sex on the high protein diets, but the response to lysine supplementation increased as the protein content of the diet was decreased. The general effect, for each sex, was that the addition of lysine decreased the protein requirement for maximum growth by at least two percentage units. In no case, however, did the growth obtained to six weeks with a lysine-supplemented 21 or 23 percent protein diet equal that obtained with the higher protein diets without added lysine. Actually, the poults fed the 21 percent diet with added lysine weighed approximately 9 percent less than poults fed the 27 percent protein diet without added lysine.
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At 12 weeks, the poults were again rerandomized into 24 new experimental groups with the same number of poults from each previous dietary treatment assigned to each new experimental pen. Six protein levels, varying from 10 to 20 percent at 2 percent intervals, were fed during the 12 to 24 week period with four experimental pens per treatment. The lysinesupplementation portion of the experiment was discontinued at 12 weeks. Poults were weighed individually and feed consumption was calculated at three week intervals to 12 weeks of age and each four weeks thereafter. The basal diets for the lowest protein level ration in each period are given in Table 1. Variations in protein level were obtained by varying the corn and soybean oil meal. No attempt was made to maintain the same energy level in the diets of differing protein levels. Although this tech-
LYSINE AND PROTEIN REQUIREMENTS OF TURKEYS
TABLE 2.—Effect
887
of protein level and added lysine on weight and feed efficiency of poults 0-6 weeks1
Without added lysine
With added lysinef
Actual analyses (%)* Weight (grams) Protein
M 21.2 23.3 25.2 27.2 29.3 31.3
1.12 1.27 1.41 1.55 1.70 1.85
Weight (grams) - Feed/gain
- Feed/gain
Lysine 1023 1139 1186 1196 1183 1224
Av. 914 1006 1026 1076 1061 1077
968 1072 1106 1136 1122 1151
M 2.20 2.18 2.17 2.13 2.19 2.27
1116 1160 1237 1234 1221 1236
Av.
971 1026 1101 1101 1067 1058
1044 1093 1169 1167 1144 1147
2.20 2.09 2.05 2.17 2.20 2.22
In this respect, the results reported here differ from those of Baldini et al. (1954) and Fisher et al. (1956), but support the results reported by Klain, Hill and Slinger (1954) and Ferguson et al. (1956). It should be observed that Klain et al. and Ferguson et al. used Bronze poults and that the rate of growth was comparable to that achieved in the experiments reported here. Baldini et al. (1954) and Fisher et al. (1956) used Jersey Buff poults and it may well be that the slower gains of the poults in their experiments reflect a lower lysine and protein requirement for this variety. In the experiments reported here, lysine supplementation increased growth appreciably only when the diet contained less than 1.55 percent lysine. The addition of 0.076 percent L-lysine to the 27 percent protein diet (1.55 percent lysine) increased poult growth by only 3 percent, and lysine additions to the 29 percent protein diet (1.70 percent lysine) produced no appreciable improvement in growth. Among the lysinesupplemented diets, maximum growth was obtained with each sex on the 25 percent protein diet containing a total (bound plus added free lysine) of 1.49 percent lysine. Increasing the protein in this case to 27 percent (total lysine 1.63 percent) did not increase growth. These results indicate a
lysine requirement of at least 1.49 percent for a 25 percent protein diet containing 814 Calories and about 1.55 percent for a 27 percent protein diet containing 796 Calories productive energy per pound. This reflects a slightly higher lysine requirement than that reported by Almquist (1952) and considerably above that reported by Kratzer, Davis and Marshall (1956). It should be noted, however, that the conclusion of Kratzer et al. (1956) regarding the lysine requirement of the poult to four weeks of age was based mainly on a previously published paper by the same authors (Kratzer et al., 1955), and that in this report 13.6 percent of the poults exhibited white barring at four weeks even when fed a 26 percent protein ration containing 1.39 percent lysine (5.3 percent lysine of protein). An analysis of the data on feed required per pound of gain in the 0-6 weeks' period revealed no significant differences among lots fed lysine-supplemented and unsupplemented diets. Although lysine apparently improved the feed efficiency with 23 or 25 percent protein diets, no improvement was obtained by supplementing the 21 percent protein diet or those diets containing 2 7 or 29 percent protein. It must be concluded, therefore, that the variation in such factors
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1 Four pens of 14 Bronze poults each per experimental treatment. * Of diet before lysine supplementation. Protein by Kjeldahl analysis; lysine determined by microbiological assay. f L-lysine HC1 9 5 % equiv. to 0.076% L-lysine.
S. L. BALLOUN AND R. E. PHILLIPS TABLE 3.—Effect of protein level and added lysine on weight gains ant efficiency of poults in the 6-12 weeks' period1 Without added ly jne
Calculateci analyses Protein
Lysine
With added lysine*
Weight (grams)
Weight (grams) - Feed/gain
- Feed/gain
(%)
(%)
M
F
Av.
15 17 19 21 23 25
0.68 0.80 0.93 1.07 1.21 1.34
1285 1807 2246 2508 2710 2593
1043 1455 1802 2009 2064 2091
1164 1631 2024 2258 2387 2342
3.76 3.17 2.84 2.66 2.65 2.58
M
F
Av.
1564 2092 2388 2620 2708 2627
1252 1657 1852 2054 2010 2136
1408 1875 2120 2337 2359 2381
3.50 2.86 2.73 2.66 2.66 2.62
as feed wastage and individual variations made it impossible to measure precisely the feed utilization differences due to lysine supplementation in this phase of the experiment. 6 to 12 weeks. As shown in Table 3, the protein requirement for maximum growth in the 6-12 week period was not over 23 percent for males and 21 percent for females without lysine supplementation since growth rates reached a practical plateau at these levels. When the diets were supplemented with
lysine, there was an appreciable improvement in both feed conversion and in weight gains for the lower protein diets. No further improvements in weight gains or feed conversion were obtained by increasing the protein above 21 percent in a lysine-supplemented diet. Figure 1 shows graphically the effect of lysine supplementation at the various protein levels in the 6 to 12 weeks' period. The general effect of adding lysine was to reduce the protein required for maximum growth and feed conversion approximately
3000]
15
17
19 21 PROTEIN IN RATION
23
25
FIG. 1. Effect of protein level and added lysine on poult gains and feed efficiency in the 6-12 week period.
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Duplicate pens of 24 poults each per experimental treatment. ' L-lysine HC1 9 5 % equiv. to 0.076% L-lysine.
•
LYSINE AND PROTEIN REQUIREMENTS OF TURKEYS
Since toms and hens were housed together, feed conversion could not be cal^ k u l a t e d for the separate sexes. However, for ^ ^ h e mixed-sex pens, a significant improvement in feed efficiency was obtained by adding lysine to diets containing 19 percent or less protein in the 6-12 week period (Figure 1). No improvement in feed efficiency was realized by increasing the protein of the diet above 21 percent. These results verify the observations of Yacowitz et al. (1956) as to protein requirements of turkeys at this age. These authors did not use diets with less than 20 percent protein, but they showed that no improvement was obtained by using more than 20 percent protein in the diets of turkeys between 9 and 16 weeks. The increased response of males in our trials to 23 percent protein diets as compared to 21 percent was probably due to the younger age (6-12 weeks). These results also agree with those of Kratzer, Davis and Marshall (1956) as to protein requirements, but indicate a con-
•
siderably higher lysine requirement for poults at this age. Kratzer et al. concluded that lysine requirement is approximately 4.75 percent of the protein to four weeks of age and then drops to approximately 4.00. In the trials reported here, growth of males in the 6-12 weeks' period was improved nearly 22 percent by lysine supplementation when the diet contained 15 percent protein and approximately 5 percent of this was lysine. Even with a diet containing 19 percent protein and 0.93 percent lysine significant growth response was obtained with males by supplementing the diet with lysine. The results of Kratzer et al. would indicate that one should not expect lysine supplementation to improve a diet containing this much lysine. It must be remembered, however, that Kratzer et al indicate average requirements of males and females, but even for a mixed flock the results presented here indicate that the lysine requirement is at least 5 percent of the protein for the rapidly growing poult at 6 weeks of age. 12 to 24 weeks. At 12 weeks of age the turkeys were re-randomized into new experimental lots as described previously. Lysinesupplementation was discontinued at this time and emphasis was placed on determining optimum protein levels for maximum gain, feed efficiency and least-cost. Six protein levels ranging from 10 to 20 percent were fed in this period with 4 replicate lots per each experimental diet. The results otbtained in the period are shown in Table 4. The requirement for maximum growth of males was 20 and for females 18 percent protein during the 1216 week period. As the birds grew older, the protein requirement decreased rapidly so that by the 20-24 week period females fed 12 percent protein and males fed 14 percent protein were rapidly making up earlier deficiencies in gains and were approaching the weights of birds fed higher
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2 percentage units. This figure also illustrates the higher requirement of males for lysine and protein. Growth response to lysine supplementation was obtained with males when the diet contained 21 percent or less protein. With females, the addition of lysine did not improve growth significantly when the diet contained 19 percent or more protein. Calculation of the lysine content of the diets indicates that for males, 1.21 percent lysine was sufficient for maximum growth in a diet containing 23 percent protein and 830 Calories productive energy per pound in this period. For females, since only slight increases in growth resulted from adding lysine to diets containing 19 percent or more protein, 0.93 percent lysine appears sufficient in a diet containing this level of protein and 866 Calories productive energy per pound.
889
890
S. L. BALLOUN AND R. E. PHILLIPS TABLE 4.—Effect
16-20 wks.
12-16 wks. Protein in ration
(%) 10 12 14 16 18 20
conversion of poults
of protein level on growth m in the period, 12-24 weeks1
20-24 wks. Gain
Gain
Gain M
F
Av.
0.57 3.16 4.16 5.05 5.41 5.72
0.58 2.48 3.24 3.70 4.03 4.08
0.57 2.82 3.70 4.37 4.72 4.90
15.7 4.5 3.9 3.6 3.4 3.3
F/g
F/g
F/g M
F
Av.
1.49 3.82 4.95 5.63 5.54 5.84
1.51 3.20 3.65 3.48 3.53 3.45
1.50 3.51 4.30 4.56 4.54 4.65
8.7 5.3 4.7 4.8 5.2 5.0
M
F
Av.
2.95 5.66 6.05 5.20 5.25 4.68
2.53 3.53 3.06 2.76 2.64 2.67
2.74 4.60 4.56 3.98 3.94 3.67
7.2 6.0 6.6 7.8 8.4 8.8
protein levels throughout the 12-24 weeks' period. While the 20-24 weeks' data cannot be statistically evaluated alone, evidence seems clear that at this age, a 12 percent protein diet will produce satisfactory gains and feed efficiency. The extreme deficiency of the 10 percent protein ration caused a severe retardment of development in the 12-16 week period which was not overcome by the 24th week. The possibility remains, however, that very low-protein, high-energy rations (10-12 percent protein) could be successfully fed in a finishing period if the birds had been grown to 20 weeks at a normal rate of gain. Calculations of least-cost rations based on the data obtained in these experiments (Heady et al., 1956; and Balloun et al., 1957) show that for most normal soybean oil meal: corn price ratios, the least-cost ration for any given period is somewhat lower in protein than is required for maximum growth. For example, with a soy bean oil meal: corn price ratio of 1.4 (soybean oil meal $70 per ton and corn $50 per ton) the least-cost ration would have been 24 percent protein in the 0-6 weeks' period while a 2 7 percent protein ration produced maximum gains. For the 6-12 weeks' period, with the same price ratio, the least-cost ration was 21 percent protein while the maximum growth was obtained with a 23 percent protein ration.
SUMMARY
The protein requirement of Broad Breasted Bronze poults was found to be at least 27 percent to six weeks of age. When diets were supplemented with lysine, maximum growth and feed efficiency was obtained with 25 percent protein diets. Added lysine improved growth and feed efficiency in the 0-6 weeks' period when the diet contained less than 1.55 percent lysine. In the 6-12 weeks' period, maximum growth was achieved when the males were fed 23 and the females 21 percent protein. Lysine supplementation reduced this requirement by about 2 percentage units. The protein requirement of the poult at 12 weeks was 20 percent, decreasing rapidly thereafter to about 12 percent at 24 weeks. At all ages, the optimum protein level for best feed efficiency and least-cost was somewhat lower than that for maximum weight gains. REFERENCES Almquist, H. J., 1952. Amino acid requirements of chickens and turkeys—a review. Poultry Sci. 3 1 : 966-981. Baldini, J. T., H. R. Rosenberg and J. Wadell, 1954. The protein requirement of the turkey poult. Poultry Sci. 33: 539-543. Balloun, S. L., G. W. Dean and E. O. Heady, 19S7. Least-cost rations for turkeys. Farm Sci. 11: 433-436. Ferguson, T. M., H. P. Vaught, B. L. Reid and
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Four pens of 24 Bronze poults each per experimental treatment.
LYSINE AND PROTEIN REQUIREMENTS OF TURKEYS
Supplementation of poult diets with lysine. Poultry Sci. 33 : 1280-1282. Kratzer, F. H., P. N. Davis and B. J. Marshall, 1955. Cottonseed meal in rations for starting poults, growing turkeys and turkey breeder hens. Poultry Sci. 34: 462-468. Kratzer, F. H., P. N. Davis and B. J. Marshall, 1956. The protein and lysine requirements of turkeys at various ages. Poultry Sci. 35: 197202. Yacowitz, H., R. D. Carter, J. Wyne and M. G. McCartney, 1956. Effects of varying protein and fat levels in a finishing ration for turkey broilers. Poultry Sci. 35: 227-229.
Mechanisms of Shell Egg Deterioration: Comparisons of Chicken and Duck Eggs 12 MARVIN
B.
R H O D E S AND ROBERT E.
FEENEY
Department of Biochemistry and Nutrition, College of Agriculture, University of Nebraska, Lincoln, Nebraska (Received for publication March 20, 1957)
INTRODUCTION
to a basic understanding ONEof approach biological systems is through a comparative study of the physical and biochemical properties of closely related species. It is the purpose of such studies to utilize the subtle differences provided by nature to determine the relative significances and roles of the individual components of the systems. An attempt has been made to utilize such an approach in the present investigation. A comparative study of certain properties of chicken and duck eggs has been made in order to obtain information basic to the understanding of the causes and mechanisms of the deteriora1
Published with the approval of the Director as Paper 808, Journal Series, Nebraska Agricultural Experiment Station. 2 This work supported in part by RMA funds through the Regional Research Project under the NCM-7 Technical Committee.
tions of quality of chicken eggs during storage. Chicken and duck eggs have been reported to have closely similar compositions. Chemically, they apparently differ primarily in the relative amounts of their various constituents and in minor (but important) differences in the molecular structure of the individual components. Most of the information available on this subject refers to the egg whites. Bain and Deutsch (1947) in an electrophoretic study found important differences in the ovalbumin, conalbumin and lysozyme contents. These differences were confirmed by means of chemical and biochemical analyses by MacDonnell, Ducay, Sugihara and Feeney (1954) who also reported a significant difference in the content of ovomucoid and in the nature of the sulfhydryl groups. In a further study, Sugihara, MacDonnell, Knight and Feeney (1955) found large differences in the contents of virus antihemagglutinin activity
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J. R. Couch, 1956. The effect of amino acid supplements to the diet of Broad Breasted Bronze turkey poults fed various levels of protein and productive energy. Poultry Sci. 35: 1069-1073. Fisher, H., J. Dowling, Jr. and K. H. Maddy, 1956. Low protein diets for turkeys raised under practical conditions. Poultry Sci. 35: 239241. Heady, E. O., S. Balloun and G. W. Dean, 1956. Least-cost rations and optimum marketing weights for turkeys. Iowa Agr. Exp. Sta. Res. Bui. 443. Klain, G. J., D. C. Hill and S. J. Slinger, 1954.
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