Effect of supplementing a enzyme mixture in sorghum+soybean meal diets on apparent ileal amino acid and protein digestibility, metabolizable energy, and productivity in broilers.

摘要

The effect of a commercial enzyme mixture (pectinases, a-glucanases and hemicellulases) added to sorghum+soyabean meal diets on apparent ileal amino acid and protein digestibility, metabolizable energy and productive performance of broilers was evaluated in two experiments. Both experiments included four treatments: control, sorghum+soyabean meal diet; control diet+enzymes; low-nutrient sorghum+soyabean meal diet 7% reduction in crude protein (CP), amino acids (AA) and metabolizable energy (ME); and low-nutrient diet+enzymes. A completely randomized design with a 2x2 factorial arrangement was used in both experiments; one factor was diet (control and low-nutrient) and the other factor was addition or not of enzymes. Exp 1 included 240 Ross 308 broiler chicks in a trial from 1 to 21 day of age, and Exp 2 included 280 Ross 308 chicks in a trial from 1 to 49 days of age. Results revealed that weight gain was lower (P<0.05) in the low-nutrient diets, but improved with addition of enzymes in Exp 1 (day 21). Ileal amino acid digestibility and ME was best (3.0% and 6.5% respectively) in the low-nutrient diet with enzymes. Weight gain was lower (P<0.05) in the low-nutrient diets, but improved with addition of enzymes in Exp 2 (day 49). The addition of the enzyme mixture improved the nutritional value of sorghum-soyabean meal diets for broilers by increasing the amino acid digestibility and metabolizable energy. It is suggested that the it is possible to use enzymes to produce low cost feeds with adequate nutritional content and growth performance comparable with conventional feeds.