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

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.