Performance of Growing Pullets and Laying Hens Fed Low-Protein, Amino Acid-Supplemented Diets1 KAVOUS KESHAVARZ2 Department of Animal Science, Morrison Hall, Cornell University, Ithaca, New York 14853 MARK E. JACKSON Continental Grain Company, 565 Lakeview Parkway, Suite 250, Vernon Hills, Illinois 60061 (Received for publication October 4, 1991) ABSTRACT An experiment was conducted to determine the effect of feeding low-protein, amino acid-supplemented diets during growing and laying periods on performance of a commercial strain of White Leghorn chickens. The birds of the positive control were fed diets in a sequence of 20, 16, and 14% protein during 0 to 6,6 to 12, and 12 to 18 wk (growing period) and of 18,16.5, and 15% protein during 18 to 34,34 to 50, and 50 to 66 wk of age (laving period). The birds of the negative control were fed protein levels of 16,13.5, and 11.5% in the growing period and 14,13, and 12% in the laying period. Other groups were fed the negative control series supplemented with methionine, methionine plus lysine, or methionine plus lysine plus other deficient essential amino acids. An additional group was fed the negative control supplemented with methionine plus lysine during the growing period and a protein sequence of 15,14, and 13% supplemented with methionine and lysine during the laying period. At 18 wk of age, birds fed the negative control supplemented with methionine plus lysine or methionine plus lysine plus other deficient essential amino acids had comparable body weight to those fed the positive control despite significantly lower protein and lysine intake. Overall egg production and egg weight of birds fed the sequence of 14,13, and 12% protein supplemented with combination of methionine, lysine, and extra levels of tryptophan and isoleucine or of the birds fed the sequence of 15,14, and 13% protein supplemented with methionine and lysine were not different from those fed the positive control. However, egg mass and body weight were inferior to those of birds fed the positive control. (Key words: growing pullets, laying hens, protein levels, amino acid supplementation, performance) 1992 Poultry Science 71:905^918
protein sources are the most expensive component of the poultry rations. Efforts Feed is the major item of cost in the to reduce dietary protein during the production of poultry meat and eggs, and growing and laying periods by proper amino acid supplementation have been the subject of numerous investigations. Supported in part from grants from Heartland Several investigators reported that the use Lysine, Inc., Chicago, IL 60631, and Agway, Inc., Syra- of low-protein diets during the growing cuse, NY 13221. period results in lighter body weight at 20 To whom correspondence should be addressed: Dr. K. Keshavarz, 247Morrison Hall, Cornell Universi- wk of age, however, such dietary manipulation did not have an adverse effect on ty, Ithaca, NY 14853. INTRODUCTION
905
906
KESHAVARZ A N D JACKSON
subsequent performance (Bullock et ah, 1963; Lillie and Denton, 1966; Stockland and Blaylock, 1974; Leeson and Summer, 1982; Maurice et ah, 1982; Keshavarz, 1984). On the other hand, inconsistency exists in the literature regarding the effect of low-protein, amino acid-supplemented diets on performance during the laying period. Johnson and Fisher (1958) reported that a 10.4% protein diet supplemented with methionine and lysine resulted in egg production performance comparable to that obtained with a 15.7% protein diet. Bray (1964) reported that egg yield and body weight changes of hens fed a diet containing 11.97% protein and adequate levels of essential amino acids were as satisfactory as those fed an 18% protein diet. Similarly, several other investigators reported that performance of hens fed low-protein diets supplemented with methionine or methionine plus lysine was comparable to that of hens fed the higher levels of protein (Fernandez et ah, 1973; Reid and Weber, 1974; Roland, 1980). In contrast, the present authors observed in several studies that the performance of h e n s fed l o w - p r o t e i n , a m i n o acidsupplemented diets was inferior to that of h e n s fed h i g h e r levels of p r o t e i n (Keshavarz et ah, 1980; Keshavarz, 1984, 1986). Similarly, Calderon and Jensen (1990) and Jensen et al. (1990) reported that the performance of hens fed a 13 or a 14% protein diet containing adequate levels of essential amino acids was not as satisfactory as that of hens fed 16% or more protein. Until recently, only methionine and lysine were commercially available. Due to the current availability of several other essential amino acids and the promises for availability of others in the near future, the effect of low-protein, amino acidsupplemented diets on the performance and economic return of poultry warrants future experimentation. Furthermore, successful implementation of such regimens will reduce nitrogen excretion and environmental pollution. The following experiment was conducted to determine the effect of feeding low-protein, amino acidsupplemented diets during the growing and laying periods on performance of a
1 + +a + •fcj "551i5 + "5
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+ + +H+H
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TABLE 2. Composition of growing rations
908
KESHAVARZ AND JACKSON
commercial strain of White Leghorn chickens. MATERIALS AND METHODS Fourteen hundred day-old chicks of a commercial strain were used in the present experiment. Groups of 20 day-old chicks were randomly placed in the top cage (61 x 51 cm) in a two-tier, windowless growing house with controlled ventilation and lighting. Two adjacent cages were considered an experimental replicate and each dietary treatment was fed to five such replicates (200 birds per treatment). At 6 wk of age, the group size was halved by transferring 10 pullets to the bottom tier. The feeding regimens used in the growing period are shown in Table 1 a nd the composition of the growing diets are shown in Table 2. The birds of the positive control (Tl) were fed a sequence of 20, 16, and 14% protein for the age period of 0 to 6, 6 to 12, and 12 to 18 wk, respectively. The essential amino acid content of these diets were adequate to satisfy the requirements as suggested by National Research Council (NRC, 1984). The birds of the negative control (T2) were fed a sequence of 16, 13.5, and 11.5% protein for similar age periods. The negative control regimen was deficient in several essential amino acids for growing pullets. The birds of T3, T4, and T5 were fed the negative control supplemented with methionine (T3), methionine and lysine (T4), and methionine, lysine, and the other deficient essential amino acids (T5) to satisfy the need for these amino acids in the growing period (NRC, 1984). The birds of T6 and T7 were fed diets similar to those of T4 and Tl, respectively, and were considered for further treatments in the laying period. Supplemental methionine and threonine were replaced with glutamic acid and supplemental lysine and arginine were replaced with glycine (on a weight for weight basis) to keep the nitrogen content of grower diets T2 to T5 approximately equal. Birds of each replicate were weighed in groups at 6, 12, and 18 wk of age. Feed consumption was recorded on a group basis at the weighing dates. At 18 w k of age, 30 birds from each
replicate were randomly selected and transferred to a high-rise, environmentally controlled, three-tier cage laying house. The pullets of each replicate were housed five per deep-designed cage (38.1 X 50.8 cm) in six adjacent cages. Each laying regimen was fed to five replicates (150 pullets per treatment). The birds of Tl of the growing regimen were fed a sequence of 18, 16.5, and 15% protein for age periods of 18 to 34 wk (Phase 1), 34 to 50 wk (Phase 2), and 50 to 66 wk (Phase 3), respectively (Table 1). This protein sequence was considered as the positive control in the laying period. The essential amino acid content of the positive control diets were calculated to be adequate to satisfy the NRC (1984) requirement (Table 3). The pullets of T2 of the growing regimen were fed a sequence of 14,13, and 12% protein for similar age periods as those fed the positive control. This dietary regimen was considered the negative control in the laying period. The 14 and 13% protein diets of the negative control contained adequate levels of all essential amino acids with the exception of total sulfur amino acids and lysine. However, the 12% protein diet was deficient in several essential amino acids. With the exception of methionine and lysine, the other essential amino acids were increased in this diet to satisfy their requirements. The birds of the T3 and T4 were fed the negative control used in the laying period supplemented with adequate levels of methionine (T3) and methionine plus lysine (T4). The birds of T5 were fed similar diets to those used by the birds of T4 in the laying period with the exception that the levels of tryptophan and isoleucine were increased further in this regimen (.17 and .68%, respectively). The birds of T6 were fed a sequence of 15, 14, and 13% protein supplemented with adequate levels of methionine and lysine for age periods of 18 to 34, 34 to 50, and 50 to 66 wk, respectively. The birds of T7 were fed diets similar to those used by the birds of T4 during the laying period. Supplemental methionine, tryptophan, and isoleucine were replaced with glutamic acid and supplemental lysine was replaced with glycine in diets T2 to T5 to keep the
Tl
.
.. .021. .06 .
.077 .067
1.13 25 .15 1.7
60.6 10.716 13.27 3 .4 8.64
Tl
.052.
1.1 .25 .15 1.9
1.13 25 .15 1.9 266 .158 .166
1.13 25 .15 1.9 .10 .158.
A 8.65
.4 8.65
.4 8.585
22.02
63.656 11.6 11.84
63.656 11.6 11.84
(%)
.158 .166
T6
.. .017. .083.
.158 .166
1.13 25 .15 1.9
.4 8.65
63.656 11.6 11.84
T5
1.13 .25 .15 1.9 .10 .
.4 8.65
63.656 11.6 11.84
T4
34 to 50 wk T3
65.543
T2
.05 .132
1.13 25 .15 1.9
.4 8.64
63.618 8.82 14.91
2,901 2,900 2,901 2,904 2,906 2,901 2,899 2,901 2,903 2,906 2,908 2,898 18 14 14 15 163 13 13 13 13 14 14 14 .7 .7 .876 .7 .7 .7 376 .7 .552 .858 376 .552 359 38 341 376 376 232 397 397 397 376 341 .274 .6 .6 .6 .628 .6 .6 .6 .6 .6 .436 .6 .498 .153 .17 .17 211 .149 .149 .17 .166 .207 .153 .153 .149 394 323 323 323 323 57 .722 346 .546 346 .676 346 .822 .919 1.177 1.138 .822 .822 .822 .814 .814 .814 .912 .814 .686 397 397 .597 .68 .662 .863 .62 .62 .68 .808 .62 33 3.5 33 33 33 33 33 33 3.5 33 3.5 33 32 32 32 .32 32 32 32 .32 32 .32 32 32 13.4 133 14.7 14.0 153 16.5 13.3 13.2 14.1 183 143 14.1
..
.189 .103
.189 .103
.103
1.13 25 .15 1.7
1.13 .25 .15 1.7 .081.
1.13 .25 .15 1.7 .081 .189.
1.13 .25 .15 1.7 .184 .189
60 14.247 10.1 3 .4 8.65
T6
60 14.247 10.1 3 .4 8.65
T5
60 14.247 10.1 3 .4 8.65
T4
18 to 34 wk
T3
60 14.247 10.1 3 .4 8.65
T2
TJased on National Research Council (1984) tables of feed composition.
Mineral mix provided the following per kilogram of diet: Mn, 60 mg; Zn, 50 mg; Fe, 30 mg; Cu, 5 mg; I, 1.06 mg; Se, .1
Vitamin mix provided the following per kilogram of diet: vitamin A, 8,800 IU; cholecaldferol, 2,200 ICU; vitamin E, 11IU; menadion add, 8.8 mg; niadn, 44 mg; vitamin Bg, 2.2 mg; folic add, .55 mg; d-biotin, .11 mg; thiamine, 22 mg; vitamin Bj2, 6.6 ng; chol
Calculated analysis Energy, kcal ME/kg Protein Lysine Methionine Methionine + cystine Tryptophan Threonine Arginine Isoleudne Calcium Available phosphorus Protein (determined)
Corn 62.955 Barley . . . Soybean meal, dehulled 21.85 Corn gluten meal 3 Salt .4 Limestone 8395 Mono-dicaldum phosphate 1.1 Vitamin mixture," .25 Mineral mixture^ .15 Blended fat 1.7 L-ghitamic add L-glydne L-lysine HC1 DL-methionine L-arginine HC1 L-threonine L-tryptophan L-isoleudne
and analysis
Tn£**w4iAnfo
TABLE 3. Composition of laying rations
KESHAVARZ AND JACKSON
910
nitrogen content equal during the layer phase. Daily egg production and weekly feed consumption records were kept during the laying period and were summarized on a 28-day basis. Egg weight and shell strength were determined for all eggs laid during the last day of every 8-wk period during the laying cycle. Eggshell strength was determined by a mechanical press as described by Scott et al. (1971). Body weight was determined at the termination of the experiment. Birds were exposed to continuous light for the first 3 days in the growing period followed by 9 h light/day up to 18 wk of age. In the laying period, birds were exposed to 16 h of light/day. Feed and water were provided for ad libitum consumption during the growing and laying periods. All data were analyzed by a one-way analysis of variance (Steel and Torrie, 1960) and treatment means were compared using Duncan's (1955) multiple range test. The protein intake in the growing and laying periods was based on determined values, and essential amino acid intake was based on calculated values using NRC (1984) tables of feed composition. A representative sample from each finished feed was saved after each mix. The samples were then blended at the end of each period (6, 12, and 18 wk) during the growing stage and at the end of each phase (34, 50, and 66 wk) during the laying stage of the experiment. The nitrogen content of feed samples were determined by the Association of Official Analytical Chemists (1980) method.
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Body weight, feed intake, and nutrient intake of birds fed the negative control diets were lower (P
protein sources are the most expensive component of the poultry rations. Efforts Feed is the major item of cost in the to reduce dietary protein during the production of poultry meat and eggs, and growing and laying periods by proper amino acid supplementation have been the subject of numerous investigations. Supported in part from grants from Heartland Several investigators reported that the use Lysine, Inc., Chicago, IL 60631, and Agway, Inc., Syra- of low-protein diets during the growing cuse, NY 13221. period results in lighter body weight at 20 To whom correspondence should be addressed: Dr. K. Keshavarz, 247Morrison Hall, Cornell Universi- wk of age, however, such dietary manipulation did not have an adverse effect on ty, Ithaca, NY 14853. INTRODUCTION
905
906
KESHAVARZ A N D JACKSON
subsequent performance (Bullock et ah, 1963; Lillie and Denton, 1966; Stockland and Blaylock, 1974; Leeson and Summer, 1982; Maurice et ah, 1982; Keshavarz, 1984). On the other hand, inconsistency exists in the literature regarding the effect of low-protein, amino acid-supplemented diets on performance during the laying period. Johnson and Fisher (1958) reported that a 10.4% protein diet supplemented with methionine and lysine resulted in egg production performance comparable to that obtained with a 15.7% protein diet. Bray (1964) reported that egg yield and body weight changes of hens fed a diet containing 11.97% protein and adequate levels of essential amino acids were as satisfactory as those fed an 18% protein diet. Similarly, several other investigators reported that performance of hens fed low-protein diets supplemented with methionine or methionine plus lysine was comparable to that of hens fed the higher levels of protein (Fernandez et ah, 1973; Reid and Weber, 1974; Roland, 1980). In contrast, the present authors observed in several studies that the performance of h e n s fed l o w - p r o t e i n , a m i n o acidsupplemented diets was inferior to that of h e n s fed h i g h e r levels of p r o t e i n (Keshavarz et ah, 1980; Keshavarz, 1984, 1986). Similarly, Calderon and Jensen (1990) and Jensen et al. (1990) reported that the performance of hens fed a 13 or a 14% protein diet containing adequate levels of essential amino acids was not as satisfactory as that of hens fed 16% or more protein. Until recently, only methionine and lysine were commercially available. Due to the current availability of several other essential amino acids and the promises for availability of others in the near future, the effect of low-protein, amino acidsupplemented diets on the performance and economic return of poultry warrants future experimentation. Furthermore, successful implementation of such regimens will reduce nitrogen excretion and environmental pollution. The following experiment was conducted to determine the effect of feeding low-protein, amino acidsupplemented diets during the growing and laying periods on performance of a
1 + +a + •fcj "551i5 + "5
2 2 2 frS% in
+ + +H+H
•9 a.
i
+ +CJ + 1u "S "S3 + %
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§
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+ + + E- + H 00 T* T* •Hi*»T»tR
TABLE 2. Composition of growing rations
908
KESHAVARZ AND JACKSON
commercial strain of White Leghorn chickens. MATERIALS AND METHODS Fourteen hundred day-old chicks of a commercial strain were used in the present experiment. Groups of 20 day-old chicks were randomly placed in the top cage (61 x 51 cm) in a two-tier, windowless growing house with controlled ventilation and lighting. Two adjacent cages were considered an experimental replicate and each dietary treatment was fed to five such replicates (200 birds per treatment). At 6 wk of age, the group size was halved by transferring 10 pullets to the bottom tier. The feeding regimens used in the growing period are shown in Table 1 a nd the composition of the growing diets are shown in Table 2. The birds of the positive control (Tl) were fed a sequence of 20, 16, and 14% protein for the age period of 0 to 6, 6 to 12, and 12 to 18 wk, respectively. The essential amino acid content of these diets were adequate to satisfy the requirements as suggested by National Research Council (NRC, 1984). The birds of the negative control (T2) were fed a sequence of 16, 13.5, and 11.5% protein for similar age periods. The negative control regimen was deficient in several essential amino acids for growing pullets. The birds of T3, T4, and T5 were fed the negative control supplemented with methionine (T3), methionine and lysine (T4), and methionine, lysine, and the other deficient essential amino acids (T5) to satisfy the need for these amino acids in the growing period (NRC, 1984). The birds of T6 and T7 were fed diets similar to those of T4 and Tl, respectively, and were considered for further treatments in the laying period. Supplemental methionine and threonine were replaced with glutamic acid and supplemental lysine and arginine were replaced with glycine (on a weight for weight basis) to keep the nitrogen content of grower diets T2 to T5 approximately equal. Birds of each replicate were weighed in groups at 6, 12, and 18 wk of age. Feed consumption was recorded on a group basis at the weighing dates. At 18 w k of age, 30 birds from each
replicate were randomly selected and transferred to a high-rise, environmentally controlled, three-tier cage laying house. The pullets of each replicate were housed five per deep-designed cage (38.1 X 50.8 cm) in six adjacent cages. Each laying regimen was fed to five replicates (150 pullets per treatment). The birds of Tl of the growing regimen were fed a sequence of 18, 16.5, and 15% protein for age periods of 18 to 34 wk (Phase 1), 34 to 50 wk (Phase 2), and 50 to 66 wk (Phase 3), respectively (Table 1). This protein sequence was considered as the positive control in the laying period. The essential amino acid content of the positive control diets were calculated to be adequate to satisfy the NRC (1984) requirement (Table 3). The pullets of T2 of the growing regimen were fed a sequence of 14,13, and 12% protein for similar age periods as those fed the positive control. This dietary regimen was considered the negative control in the laying period. The 14 and 13% protein diets of the negative control contained adequate levels of all essential amino acids with the exception of total sulfur amino acids and lysine. However, the 12% protein diet was deficient in several essential amino acids. With the exception of methionine and lysine, the other essential amino acids were increased in this diet to satisfy their requirements. The birds of the T3 and T4 were fed the negative control used in the laying period supplemented with adequate levels of methionine (T3) and methionine plus lysine (T4). The birds of T5 were fed similar diets to those used by the birds of T4 in the laying period with the exception that the levels of tryptophan and isoleucine were increased further in this regimen (.17 and .68%, respectively). The birds of T6 were fed a sequence of 15, 14, and 13% protein supplemented with adequate levels of methionine and lysine for age periods of 18 to 34, 34 to 50, and 50 to 66 wk, respectively. The birds of T7 were fed diets similar to those used by the birds of T4 during the laying period. Supplemental methionine, tryptophan, and isoleucine were replaced with glutamic acid and supplemental lysine was replaced with glycine in diets T2 to T5 to keep the
Tl
.
.. .021. .06 .
.077 .067
1.13 25 .15 1.7
60.6 10.716 13.27 3 .4 8.64
Tl
.052.
1.1 .25 .15 1.9
1.13 25 .15 1.9 266 .158 .166
1.13 25 .15 1.9 .10 .158.
A 8.65
.4 8.65
.4 8.585
22.02
63.656 11.6 11.84
63.656 11.6 11.84
(%)
.158 .166
T6
.. .017. .083.
.158 .166
1.13 25 .15 1.9
.4 8.65
63.656 11.6 11.84
T5
1.13 .25 .15 1.9 .10 .
.4 8.65
63.656 11.6 11.84
T4
34 to 50 wk T3
65.543
T2
.05 .132
1.13 25 .15 1.9
.4 8.64
63.618 8.82 14.91
2,901 2,900 2,901 2,904 2,906 2,901 2,899 2,901 2,903 2,906 2,908 2,898 18 14 14 15 163 13 13 13 13 14 14 14 .7 .7 .876 .7 .7 .7 376 .7 .552 .858 376 .552 359 38 341 376 376 232 397 397 397 376 341 .274 .6 .6 .6 .628 .6 .6 .6 .6 .6 .436 .6 .498 .153 .17 .17 211 .149 .149 .17 .166 .207 .153 .153 .149 394 323 323 323 323 57 .722 346 .546 346 .676 346 .822 .919 1.177 1.138 .822 .822 .822 .814 .814 .814 .912 .814 .686 397 397 .597 .68 .662 .863 .62 .62 .68 .808 .62 33 3.5 33 33 33 33 33 33 3.5 33 3.5 33 32 32 32 .32 32 32 32 .32 32 .32 32 32 13.4 133 14.7 14.0 153 16.5 13.3 13.2 14.1 183 143 14.1
..
.189 .103
.189 .103
.103
1.13 25 .15 1.7
1.13 .25 .15 1.7 .081.
1.13 .25 .15 1.7 .081 .189.
1.13 .25 .15 1.7 .184 .189
60 14.247 10.1 3 .4 8.65
T6
60 14.247 10.1 3 .4 8.65
T5
60 14.247 10.1 3 .4 8.65
T4
18 to 34 wk
T3
60 14.247 10.1 3 .4 8.65
T2
TJased on National Research Council (1984) tables of feed composition.
Mineral mix provided the following per kilogram of diet: Mn, 60 mg; Zn, 50 mg; Fe, 30 mg; Cu, 5 mg; I, 1.06 mg; Se, .1
Vitamin mix provided the following per kilogram of diet: vitamin A, 8,800 IU; cholecaldferol, 2,200 ICU; vitamin E, 11IU; menadion add, 8.8 mg; niadn, 44 mg; vitamin Bg, 2.2 mg; folic add, .55 mg; d-biotin, .11 mg; thiamine, 22 mg; vitamin Bj2, 6.6 ng; chol
Calculated analysis Energy, kcal ME/kg Protein Lysine Methionine Methionine + cystine Tryptophan Threonine Arginine Isoleudne Calcium Available phosphorus Protein (determined)
Corn 62.955 Barley . . . Soybean meal, dehulled 21.85 Corn gluten meal 3 Salt .4 Limestone 8395 Mono-dicaldum phosphate 1.1 Vitamin mixture," .25 Mineral mixture^ .15 Blended fat 1.7 L-ghitamic add L-glydne L-lysine HC1 DL-methionine L-arginine HC1 L-threonine L-tryptophan L-isoleudne
and analysis
Tn£**w4iAnfo
TABLE 3. Composition of laying rations
KESHAVARZ AND JACKSON
910
nitrogen content equal during the layer phase. Daily egg production and weekly feed consumption records were kept during the laying period and were summarized on a 28-day basis. Egg weight and shell strength were determined for all eggs laid during the last day of every 8-wk period during the laying cycle. Eggshell strength was determined by a mechanical press as described by Scott et al. (1971). Body weight was determined at the termination of the experiment. Birds were exposed to continuous light for the first 3 days in the growing period followed by 9 h light/day up to 18 wk of age. In the laying period, birds were exposed to 16 h of light/day. Feed and water were provided for ad libitum consumption during the growing and laying periods. All data were analyzed by a one-way analysis of variance (Steel and Torrie, 1960) and treatment means were compared using Duncan's (1955) multiple range test. The protein intake in the growing and laying periods was based on determined values, and essential amino acid intake was based on calculated values using NRC (1984) tables of feed composition. A representative sample from each finished feed was saved after each mix. The samples were then blended at the end of each period (6, 12, and 18 wk) during the growing stage and at the end of each phase (34, 50, and 66 wk) during the laying stage of the experiment. The nitrogen content of feed samples were determined by the Association of Official Analytical Chemists (1980) method.
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Body weight, feed intake, and nutrient intake of birds fed the negative control diets were lower (P
