A multienzyme preparation enhances the utilization of nutrients and energy from pure corn and wheat diets in broilers 1

A metabolic experiment was conducted to investigate the effects of 2 different types of exogenous multienzyme preparations, one used to supplement a pure corn-based broiler diet (ME-C; mainly consisting of mannase, xylanase, cellulase, pectase, prolease, and glucoamylase) and the other added to a pure wheat-based broiler diet (ME-W; mainly containing xylanase, cellulase, glucanase, pectase, amylase, and glucoamylase), on the energy efficiency and nutrient utilization of broilers. Ninety 36-d-old Arbor Acres commercial male broilers were randomly allocated to 90 cages, and 72 of them were assigned to 8 treatment groups with 3 replicates of 3 broilers each. Four treatment groups were force-fed corn with different levels of ME-C (0, 50, 100, and 150 mg/kg), and the other 4 treatment groups were force-fed wheat with different levels of ME-W (0, 50, 100, and 150 mg/kg). The remaining 18 birds were taken as 1 group, with 3 replicates of 6 birds for each, and used for endogenous excreta collection. Digestibility values of DM, NDF, starch, gross energy, and ME were measured by “true” methods. The ME-C and ME-W added to pure corn- and wheat-based diets, respectively, enhanced (P < 0.05) the apparent and true digestibility values of NDF, starch, DM, and gross energy and the AME and TME values of broilers. The nutrient digestibility and energy efficiency of corn responded quadratically (P < 0.05) to increasing amounts of ME-C. However, the digestibility of nutrients in corn did not change significantly at 100 and 150 mg/kg of ME-C, indicating a saturation effect. Thus, supplementation of 100 mg/kg of ME-C is sufficient to maximize the nutrient utilization and energy conversion of corn. However, linear (P < 0.001) and quadratic responses (P < 0.01) were observed for the nutrient digestibility and ME values in wheat-based diets with increasing amounts of ME-W added.