Versazyme supplementation of broiler diets improves market growth performance.

Day-old male broiler chicks were randomly assigned to 32 floor pens in a completely randomized block design and grown to 6 wk of age. Birds in experiment 1 were fed 1 of 2 basal diets supplemented with or without a protease containing feed additive, Versazyme (VZ). The 4 treatments were 1) control (C), a corn-soybean meal diet that contained 95% of amino acids recommended by NRC except for threonine and isoleucine; 2) C + 0.1% VZ (wt/wt) (C+) in the starter diet only; 3) high (HP) amino acid diet, a corn-soybean meal diet with 100 to 105% of amino acid recommended by NRC except for threonine and isoleucine; and 4) HP + 0.1% VZ (wt/wt) (HP+) in starter diet only. Supplementing both diets with VZ improved BW and feed conversion ratio (FCR) at 21 d of age and BW at 42 d of age. Cumulative 42-d FCR was only improved in birds fed the HP+ diet. Birds in experiment 2 received the following treatments: 1) HP, 2) HP + 0.1% VZ batch A (wt/wt) (A) in starter diet only, and 3) HP + 0.1% VZ batch B (wt/wt) (B) in starter diet only. Enzyme supplementation improved 22-d BW and FCR. There was no significant difference in BW at 43 d of age. Both A and B improved overall FCR (1.758 and 1.751 vs. 1.79 for A and B vs. HP, respectively). In conclusion, supplementation of starter broiler diets with VZ resulted in improved market growth performance.

Glucose and electrolyte supplementation of drinking water improve the immune responses of poults with inanition.

Enteric disorders predispose poultry to malnutrition. The objectives of this paper were 1) to simulate the inanition of poult enteritis mortality syndrome by restricting feed intake and 2) to develop a drinking water supplement that supports the immune functions of poults with inanition. Poults were restricted to 14 g of feed/d for 7 d beginning at 14 d of age then fed ad libitum until 36 d (recovery). The control was fed ad libitum. During the feed-restriction period, duplicate groups of 6 poults received 1 of 5 drinking water treatments: 1) restricted feed, unsupplemented water; 2) restricted feed + electrolytes (RE); 3) RE + glucose + citric acid (REGC); 4) REGC + betaine (REGCB); or 5) REGCB + zinc-methionine (REGCBZ). Immunological functions were assessed by inoculating poults with SRBC and B. abortus (BA) antigen at 15, 22, and 29 d of age. Antibody (Ab) titers were determined 7 d later for primary, secondary, and recovery responses. The primary and secondary total Ab titers to SRBC for restricted feed were 4.71 and 6.16 log3, which where lower (P < 0.05) than for controls (8.00 and 9.66 log3) and the other treatments. The recovery Ab titer for controls was 10.7, significantly higher than restricted feed (8.71) and RE (8.10) groups but not different from other treatments. The primary total Ab responses to BA were significantly lower in the restricted feed and RE groups as compared with the control and other treatments. Although feed restriction of poults to maintenance reduces the humoral immune responses, these responses can be significantly improved by drinking water containing electrolytes and especially sources of energy such as glucose and citric acid.

Keratinase in starter diets improves growth of broiler chicks.

The objective of this study was to determine the efficacy of a broad-spectrum protease enzyme, PWD-1 keratinase, upon supplementation to corn-soy starter diets on growth performance of broiler chickens. Three experiments were conducted. In each experiment, 1-d-old broiler chicks were randomly assigned to 24 cage pens of eight birds per pen in a completely randomized design of five experimental treatments and grown to 21 or 26 d of age. Treatments in experiments 1 and 2 were control (C, 21.39% CP), low protein (LP, 18% CP), and LP supplemented with 0.05, 0.1, or 0.15% enzyme preparation (wt/wt). Treatments in experiment 3 were control (C), C+ 0.1% enzyme preparation (C+E) fed starting at either 1 or 5 d of age, LP and LP+ 0.1% enzyme preparation (LP+E). Feeding the LP+E diet produced numerically higher BW at 21 d of age (experiments 1 and 3) and a significantly higher BW at 26 d of age (experiment 2; 1,025 and 1,032 g vs. 965 g for 0.1 and 0.15% vs. LP, respectively, P < 0.05). Feed conversion ratio (FCR) was also improved when chicks were fed the LP+E diet both at 21 (experiment 3) and 26 d of age (experiment 2). In experiment 3, supplementing the C diets with 0.10% enzyme resulted in improvements (P < 0.05) in BW whether the enzyme was supplemented starting at 1 d (767 vs. 695 g for C+E vs. C, respectively) or 5 d of age (764 vs. 695 g for C+E vs. C, respectively). FCR was numerically improved. Furthermore, diets supplemented with the enzyme at any level resulted in reduction of jejunal viscosity at 22 and 27 d of age (P < 0.05). Results of these experiments indicate that the growth of broiler chickens can be significantly improved by dietary supplementation with PWD-1 keratinase.

Effect of mannan-endo-1,4-beta-mannosidase on the growth performance of turkeys fed diets containing 44 and 48% crude protein soybean meal.

Soybean meal (SBM) contains heat-resistant mannans. Domesticated turkeys are sensitive to mannans because of the high inclusion rate of SBM in their diets, causing increased chyme viscosity, wet droppings, and reduced feed conversion. Three experiments of similar design were conducted to determine the effect of mannan-endo-1,4-f'-mannosidase supplementation of corn-SBM diets on market turkeys. Experiment 1 was conducted at North Carolina State University using Nicholas hens raised from 1 to 98 d of age. Experiments 2 and 3 were conducted at PARC Institute Inc. using Large White turkey toms raised from 1 to 126 d of age. In each experiment, birds were randomly assigned to litter floor pens. Each pen was assigned to one of four experimental treatments in 2 x 2 factorial arrangement of two basal diets containing 44% CP and 48% CP SBM (SBM-44 and SBM-48, respectively) with or without 100 million units (MU) Hemicell/tonne (1 MU = 106 enzyme activity U). Birds fed SBM-44 had lower final BW (14.9 vs. 14.56 kg 18 wk BW / tom; 7.66 vs. 7.46 kg 14 wk BW/hen, P < 0.05) and higher final cumulative feed/gain than those fed the SBM-48. Hemicell supplementation generally improved performance of all birds, with a greater response in birds fed SBM-44. Hemicell improved BW and feed/gain by 1% (P = 0.779) and 3% (P = 0.377) in hens and 2.5% (P = 0.0016) and 4% (P = 0.0001) in toms, respectively. The results of these experiments indicate that some of the adverse effects of antinutritional factors of SBM of on turkey growth performance can be alleviated by dietary mannan-endo-1,4-beta-mannosidase supplementation.

Effect of wheat enzyme preparation on the performance characteristics of Tom turkeys fed wheat-based rations.

Wheat contains 5 to 8% nonstarch polysaccharides (NSP). The NSP complex forms a viscous mass when fully hydrated, which impedes the absorption of nutrients from chyme and causes reduced growth performance and osmotic diarrhea and associated wet litter. These adverse effects can be alleviated by appropriate enzyme supplementation. The objective of this experiment was to evaluate the efficacy of endoxylanase and beta-glucanase enzyme mixtures supplemented to wheat-based diets on growth performance characteristics of turkeys. Seven-day-old Large White male turkeys were randomly assigned to 40 litter floor pens of 12 poults each as a completely randomized block design arrangement of four experimental treatments and were raised to 140 d. The dietary treatment consisted of a control treatment (no supplemental enzyme) and three dietary enzyme treatments: 1) Lyxasan forte, 2) Natugrain Blend, and 3) Natugrain. Body weight, feed consumption, and mortality were recorded weekly. Feather condition was evaluated at 98 d of age. Natugrain Blend improved BW at 84 d (P < 0.075) and 112 d (P < 0.01) in comparison to the unsupplemented control diet. Lyxasan forte had the best feed/gain ratio throughout the experiment. Subjective feather condition score was significantly improved (P < 0.05) by all the three enzyme treatments and corresponded with reduced incidence of neck and back picking behavior. The enzyme treatment groups had lower mortality than the control group with the Natugrain blend treatment having the lowest mortality rate through the experiment. The results of this experiment demonstrate marginal improvement in growth performance of turkeys depending upon enzyme formulation.

Growth and digestive function of turkeys surviving the poult enteritis and mortality syndrome.

Stunted growth of poults afflicted by enteritis mortality syndrome (PEMS) may be associated with depressed digestive capabilities. We conducted two experiments to test this hypothesis. Survivors of PEMS were obtained from a research flock that had been purposefully infected at 5 d of age with PEMS inoculum that included turkey corona virus. The PEMS survivors were assigned to Experiments 1 and 2, beginning at 40 and 35 d of age, respectively. Three groups (large, L; medium, M; and small, S) and two groups (L and S) of 20 poults each were selected to represent different degrees of stunting in Experiments 1 and 2, respectively. When the body weights of each group in both experiments were plotted using initial body weight as the starting point, all of the weights fell on the normal growth curve except Group S in Experiment 1. Therefore, there was no evidence of compensatory growth over the period studied. In Experiment 1, apparent fat absorption (AFA) was significantly higher (P < 0.05) for control (85.9%) than for M (78.5%) and S (78.3%) groups, and AME, for the control group was significantly higher than all the PEMS-survivor groups. In Experiment 2, Group L had a higher AFA and AMEn than Group S. AFA and AMEn improved in both groups over time. The digestive capabilities of PEMS survivors were depressed proportionally to the degree of stunting. Impaired fat digestibility and dietary energy utilization in PEMS-afflicted birds are likely contributors to stunted growth and reduced recovery rates.

Effect of Lactobacillus acidophilus and zinc bacitracin as dietary additives for broiler chickens.

The influence of Lactobacillus acidophilus and zinc bacitracin alone, or in combination, on the growth of broiler chickens was monitored over a period of 8 weeks. 2. The maximum improvement in body weight over the controls was 10.8% with both additives in the diet but the use of bacitracin alone induced a 9.1% improvement. 3. Food conversion was reduced by zinc bacitracin alone but was improved by the use of L. acidophilus and bacitracin in combination. 4. The combination treatment increased abdominal fat deposition in the female chickens by 31%.