Performance and organ morphology of broilers fed microbial or antimicrobial additives and raised in batteries or floor pens

This study was conducted to determine the effect of microbial or antimicrobial additives on the performance and organ morphology of broilers raised in batteries or in floor pens. The effect of microbial additives on the presence of oocysts in the litter was also studied. Experiments 1 and 2 consisted of four treatments (non-supplemented control diet or diet supplemented with avilamycin, bacitracin methylene disalicylate or enramycin) and six repetitions in a randomized block design. In Experiment 1, 288 day-old chicks were housed in heated batteries in a environmentally controlled room, 12 chicks per cage; in Experiment 2, 1,200 day-old chicks were housed in a curtain-sided experimental house, with concrete floor and rice hulls as litter material, 50 chicks per pen. Experiments 3 and 4 were carried out similarly to Experiments 1 and 2, respectively, but the treatments consisted of microbial additives (non-supplemented control diet or Bacillus subtilis added to the feed plus Lactobacillus reuteri and Lactobacillus johnsonii added to the water, undefined microflora added to the water or live yeast added to the feed). The antibiotics did not affect the performance of birds raised in batteries, but improved feed conversion, weight gain and live weight when chickens were kept on the floor pens. Microbial additives did not affect bird performance in any environment; however, treatments affected liver weight. Microbial agents increased intestinal weight in floor-raised broilers. No relationship was seen between the use of microbial additives and the presence of oocysts in the litter

Efficacy and Metabolizable Energy Equivalence of anα-Amylase-β-Glucanase Complex for Broilers

A trial was conducted to evaluate the effects of adding an exogenous α-amylase-β-glucanase complex produced from Bacillus amyloliquefaciens on the growth performance, carcass yield, and relative AME bioequivalence in broilers fed corn-soy diets from 1 to 40 d of age. One thousand seven hundred and fifty one-day-old Cobb x Cobb 500 slow-feathering male broilers were randomly allotted to seven treatments with 10 replicates of 25 birds each as follows: control diet (C); C diet with reduction of 60 (C-60), 90 (C-90), or 120 (C-120) kcal AME/kg; C diet with reduction of 120 kcal AME/kg and supplemented with 200 (C-120-200), 300 (C-120-300), or 400 (C-120-400) mg of the enzyme complex/kg. Each g of the enzyme complex corresponded to 200 kilo-Novo α-amylase and 350 fungal β-glucanase units. On d 40, eight birds were randomly taken from each pen and processed to evaluate carcass and commercial cuts yields. Percent mortality was not affected by the treatments (p > 0.05). Live performance, as indicated by BW gain (BWG) linearly decreased (p < 0.05) and FCR linearly increased with the reduction in AME. Birds fed diets supplemented with the enzyme complex showed weekly improvements in BWG and FCR. There were no effects of the treatments on the yield of the carcass or of commercial cuts; however, abdominal fat was significantly lower (p < 0.0343) in birds fed the C-120-400 compared to the C-120 feeding program (1.67% vs. 1.90%); all other treatments were intermediate. Average AME equivalence of the enzyme complex varied weekly. Estimations for the entire period were 40, 46, and 56 kcal for BWG and 58, 76, and 99 kcal AME/kg for FCR (p < 0.001) for the diets containing 200, 300, and 400 mg enzyme complex/kg, respectively

Determination of the energetic value of corn, soybean meal and micronized full fat soybean for newly hatched chicks

There are some evidences described in the literature showing reduced energy metabolizability of ingredients for newly hatched chicks. Hence, a metabolism trial was carried out with the objective of determining the metabolizable energy of corn grain, soybean meal and micronized full fat soybean for newly hatched chicks. The method of total excreta collection was used in an experiment with 192 male chicks from one to seven days, distributed in a completely randomized design with four treatments and four replicates of twelve birds. Excreta were collected from four to seven days of age. The treatments included a reference diet, two test-diets consisting of 60% of the reference diet and 40% of the test ingredients: corn grain (CG) and soybean meal (SM), and one test-diet consisting of 80% of the reference diet and 20% of micronized full fat soybean (MFFS). The N-corrected apparent metabolizable energy (AMEn) and the metabolizability coefficient of gross energy (MCGE) of the ingredients determined for the chicks were respectively 3,213 kcal/kg and 81.6% for CG; 2,085 kcal/kg and 49.7% for SM and 4,068 kcal/kg and 74.8% for MFFS