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Experiments were designed to investigate the effect of feeding diets deficient in one or more of the three branched-chain amino acids (BCAA) on the performance of 3-wk-old male broilers. In the first experiment, levels of .96 and 1.46% Leu, .52 and .82% Ile, and .65 and .95% Val were used. Feeding the lowest combination of the three BCAA resulted in weight gain (WG) and feed conversion ratio (FC) of 344 g and 1.59 g:g, respectively. These parameters were not improved by adding dietary increments of the three BCAA individually. The greatest response, however, for both WG (435 g) and FC (1.41 g:g) was obtained by the addition of the three BCAA simultaneously. Chicks fed the low-Val diets in combinations with added levels of Ile and Leu exhibited feather and leg abnormalities. A second experiment was designed to investigate the effect of Val deficiency on feather protein, feather amino acids, and calcium content of the bone. Three treatments were used: a BCAA-deficient diet with .96% Leu, .52% Ile, and .63% Val; a Val-deficient diet, which contained 1.37, .82, and .63% of Leu, Ile, and Val, respectively; and a Val-supplemented diet, which was the same as the previous diets except that the Val content was .83%. Valine deficiency significantly decreased WG (243 g), FC (1.69 g:g), bone calcium (134 mg/g dry bone), and feather protein (82.7% of wet weight). Valine deficiency also decreased the level of Cys in feathers, but increased those of Asp, Glu, Met, Tyr, His, and Lys.(ABSTRACT TRUNCATED AT 250 WORDS)

Two experiments were conducted to study the effect of feeding raw or treated common vetch seeds (V) on BW, feed intake (FI), egg production (EP), feed conversion (FC), egg weight (EW), shell thickness (ST), yolk color score (YC), and Haugh unit score (HU) of Single Comb White Leghorn hens for 56 d. In Experiment 1, diets contained 0, 7.5, 15, and 22.5% raw V. Compared with the control, the 22.5% V diet decreased (P < .05) BW, FI, and EP. In Experiment 2, intact or ground (G) V were either soaked (S) in water (1:5) for 24 h or autoclaved (A) at 103.5 x 10(3) Pa for 8 h, and then dried (D) at 55 C for 24 h. Eight diets were used, a corn soybean (control) and seven others, each containing 25% V, previously subjected to the forementioned treatments as follows: untreated V (UV), SDV, GSDV, ADV, GADV, SADV, and GSADV. Compared with the control, the UV diet decreased (P < .05) FI (75 vs 98 g) and EP (47.3 vs 88.7%), increased FC (1.99 vs 1.4 kg feed per dozen eggs), and induced BW loss (-63 vs 49 g). Soaking intact V improved (P < .05) FI (85 g) and EP (69%). Remaining treatments resulted in further improvement. Hens fed all V diets produced eggs with HU score 13 points better than that of the control (P < .05). In both experiments, EW, YC, and ST were not different among treatments. Results indicated that autoclaved V at 25% level was not detrimental to layers' performance.

Broiler breeders display high levels of aggressive activity as a result of feed restriction. The objective of this study was to determine if aggressive activity in developing and mature broiler breeder males is influenced by increased dietary L-tryptophan (Trp). Broiler breeder males were raised using a skip-a-day feed restriction regimen. In Experiment 1, three levels of dietary Trp, .19 (control), .75, and 1.5%, were fed from the start of feed restriction at 4 wk of age and throughout development. All occurrences of aggressive behavior were recorded during three 20-min observation sessions per week on mornings on which feed was not delivered through Week 20. The Trp significantly decreased (P less than .05) aggressive pecking in birds fed supplemental Trp as compared to controls. No differences in threatening behavior were found. In the second part of Experiment 1, the effect of continued Trp supplementation on mature flocks of male broiler breeders and time-of-day effects on aggression were investigated. A depressing effect of supplemental Trp on pecking and threatening was observed. Maximum aggressive activity in all treatment groups occurred on mornings when feed was delivered. In Experiment 2, four levels of Trp, .19 (control), .38, .75, and 1.5%, were fed to developing birds as in Experiment 1. Birds fed supplemental Trp pecked less (P less than .05) than controls and .38% Trp was as effective in decreasing pecking as was 1.5%. It was concluded that increased levels of dietary Trp decrease aggression in both developing and mature, socially stable flocks of broiler breeder males.

Day-old Arbor Acre male broiler chicks were fed 55%-rye diets with or without antibiotic supplements in three 14-day experiments. Procaine penicillin, chlortetracycline, or bacitracin methylene disalycilate were added individually to the rye basal diet at a concentration of 55 p.p.m. Weight gain and feed consumption were calculated at two-day intervals in all experiments. Chicks fed the antibiotic supplemented diets grew better than chicks on the basal diet. In each experiment chicks fed the unsupplemented diet gained weight at a linear rate for about the first eight days and exponentially thereafter. Feed conversion ratios (feed/gain) for chicks on the basal diet, calculated for each two-day interval, increased rapidly reaching a peak after eight days on the diet. Thereafter, the feed conversion ratios of the chicks on the unsupplemented diet declined until the 13—14 day interval when the experiments were terminated. All chicks exhibited a sticky feces condition regardless of the presence of antibiotics in their diet. It is concluded that young chicks adapt to diets containing rye. The adaptive response in these experiments occurred after the chicks had been on the diet for about eight days. Since the adaptation occurred only in chicks fed the unsupplemented diets, it is suggested that the adaptation is due to a change in the gut bacterial population.

Two studies were conducted in floor pen facilities to evaluate broiler diets containing various protein and amino acid levels. In Study #1 at 48 and 56 and at 49 and 59 days of age in Study #2, the number of body and flight feathers onthe litter in two separate 0.37 sq. meter areas located in the same place in each pen was recorded. In Study #1 Hubbard × Hubbard broiler crosses were employed. There were very few body feathers on the litter at 48 or 56 days of age. At 56 days the birds that had been on a high protein finisher ration had significantly (P

Two floor pen studies were conducted to determine the minimum arginine level needed to support maximum weight gain and optimum feed conversion during the 4-7 week period of growth for both males and females. Floor feather counts were used as an additional criteria for determining the arginine requirement. The basal diets were calculated to contain 0.74 and 0.80% arginine based on the analyzed values for corn, corn gluten meal, skimmilk and soybean meal. Regression equations were calculated from the data obtained for the males only. Based on the regression equations, the calculated requirement for maximum weight gain, optimum feed conversion, and floor feathers is 1.09, 1.10, and 1.13% arginine, respectively. When expressed as a function of energy, the requirements would be 0.329, 0.332, and 0.341% arginine per megacalorie of metabolizable energy per kg. of diet, respectively. The differences in rate of gain data for the females were non-significant, indicating the requirement of the females to be less than the males. The female requirement, based on floor feathers, would appear to be 0.98% dietary arginine.

A crude extract with a high proportion of pectic substances was prepared from rye. This was fed to chicks in two studies to determine if rye pectic substances are responsible for the growth depression of chicks fed rye. The growth of chicks was significantly (P greater than .01) depressed when fed a diet containing this extract. Addition of penicillin to the diet improved the growth of chicks. Increasing the concentration of the extract in the diet produced an incremental depression in weight gain. The intestines of chicks fed this extract contained large quantities of gas that were reduced by penicillin supplementation. These results suggest that rye pectic substances may be responsible for the growth depression of chicks fed rye.

Chicks which were hatch-mates were placed in rearing facilities 4 hr and 24 hr after removal from the hatchers. One-half of the birds placed at each of these times received only water for 12 hr before being given access to feed. The other half received both water and feed simultaneously. Birds that were placed in the pens 4 hr after removal from the hatchers were significantly (P≤.01) heavier at 28, 49, and 56 days of age than birds which were held in the hatchery for 24 hr prior to placement. There were no significant effects on the birds’ weight or feed conversion which could be attributed to the birds receiving only water for 12 hr or initially receiving both water and feed. There were no significant interactions between the time the birds were placed and whether they initially received only water or water and feed. Three studies were conducted to evaluate the effect of adding various supplements to the drinking water for the first 24 to 72 hr on the weight and feed conversion of broiler chickens. There were no benefits from adding 10% sucrose for 24 hr or 5% sucrose for 72 hr. In one trial, there was a significant (P

The sensitivity of several bioassays was determined using soybean meal and two autoclaved soybean meals. Chick growth study results revealed that a four percent difference in weight gain was sufficient to show statistical significance (P less than .05) between the diets. Lysine quantities and digestibility values were compared using excreta obtained from intact (excreta collected on mats or in bags), cecectomized. and ileal-cannulated roosters. A 30% difference in lysine quantity in the excreta (collected on mats) was required to detect statistically significant effects of different diets fed to intact birds. Using intact birds (excreta collected in bags), cecectomized, and cannulated birds, differences in lysine quantity of 41, 42, and 67% were required to show statistically significant effects. Results showed that altering birds did not significantly change lysine values obtained nor reduce variability among birds (P greater than .05).

Six experiments were conducted with broiler cross male chicks to determine the available lysine requirement during the 7–9 week growing period. The birds were reared from day-old to 7 weeks of age on commercial type broiler rations. At 7 weeks of age the birds were group-weighed by pens and the pens ranked according to average weight and blocked on this basis. The treatments were randomly assigned within each block. Graded levels of lysine from L-lysine · HCl were added to lysine deficient basal rations which had been formulated based on available lysine values of 0.26, 3.09, 0.71 and 1.04% for corn, soybean meal, corn gluten meal and sesame meal, respectively. Using regression analysis the minimum available lysine requirement was calculated for this period. The minimum lysine requirement for male broilers during this period was 0.68% under optimum growing conditions. In one experiment the requirement appeared to increase under summer stress conditions. When expressed as a function of energy this would be 0.201% available lysine per mega Calorie M.E. per kg. of diet.

Microbial determinations were made on excreta obtained from intact, cecectomized, and ileal-cannulated roosters. Mean diaminopimelic acid (DAP) quantities in the excreta from intact and cecectomized birds did not differ significantly. The DAP value was greater in excreta from intact and cecectomized birds when they were fed 30 g of either soybean meal or autoclaved soybean meal than when fed cornstarch (P

Studies with broiler type chickens were conducted to determine the minimum tryptophan requirement for maximum growth, optimum feed efficiency and molted body feather count for the 4–7 week period of growth for both males and females. Basal diets analyzed to contain 0.158, 0.157, and 0.147% tryptophan using analyzed tryptophan values of 0.09, 0.01, 0.31, 0.70, 0.40, and 0.46% for corn, gelatin, corn gluten meal, soybean meal, peanut meal-45, and peanut meal-50, respectively. Based on the regression equations for males, the calculated tryptophan requirement for maximum growth, optimum feed efficiency, and molted body feather count for the 4–7 week period is 0.179, 0.170, and 0.172%, respectively for 3300 Kcal. of M.E. per kg. of diet. When expressed as a function of energy, these requirements would be 0.054, 0.052, and 0.052% tryptophan per megacalorie of M.E. per kg. of diet, respectively. Based on the equations for females, the calculated tryptophan requirement for maximum growth, optimum feed efficiency, and molted body feather count is 0.173, 0.163, and 0.172%, respectively for 3300 Kcal. of M.E. per kg. of diet, respectively.