Effects of a combination of phytase and multi-carbohydrase enzymes in low-density corn–soybean meal based diets on growth performance and ileal nutrients digestibility of male broilers

摘要

A study was conducted to evaluate the effect of dietary supplementation of phytase and carbohydrase on growth performance and ileal digestibility of nutrients in broilers fed low-density corn–soybean meal-based diets. A total of 280 one-day-old Ross 308 male broilers were randomly assigned to 7 dietary treatments, with 4 replicates of 10 birds. Dietary treatments were (1) full nutrient specification without enzyme supplementation (positive control; PC), (2) diet with reduced nutrients as a phytase matrix (negative control; NC), (3) NC? ?phytase (500 FTU/kg diet), 4) NC? ?multi-carbohydrase (0.1?g/kg), (5) NC? ?phytase? ?multi-carbohydrase, (6) diet with reduced nutrients as phytase and multi-carbohydrase matrices; low negative control (LNC), and (7) LNC? ?phytase? ?multi-carbohydrase. Broilers fed either NC or LNC diets had lower body weight gain, the European production efficiency factor, and a higher feed conversion ratio than those fed PC diet ( p ?.01). Broilers fed LNC diet had lower dry matter (DM) and crude protein (CP) digestibility, and apparent ileal digestible energy (AIDE) than those fed PC diet ( p ?.01). Multi-carbohydrase supplementation on top of phytase-containing NC diets resulted in a similar effect on performance and digestibility of DM and AIDE in broilers compared with LNC diets containing phytase and multi-carbohydrase. Digestibility of CP was lower in NC? ?multi-carbohydrase groups than NC? ?phytase? ?multi-carbohydrase ( p ?.01). In conclusion, multi-carbohydrase was successful in improving broiler performance and nutrients digestibility in the diet based on the corn–soybean meal with lower nutrient density; thus, when supplementing it as a second enzyme in diets containing phytase, its matrix value should be considered for least-cost feed formulation. HIGHLIGHTS Phytase and carbohydrase matrix values should be considered when enzyme combination using in C-SBM diet. Carbohydrase improved broiler performance and nutrients digestibility in C-SBM diet with lower nutrient density. Cost-effectiveness use of enzyme combination in diets could reduce nutrient excretion.