Work

Performance and nutrient digestibility of broilers fed barley-based diets supplemented with amylase

Year: 2025

Type: article

Abstract: The objective of this study was to evaluate the effects of exogenous amylase supplementation on growth performance and apparent ileal digestibility (AID) of nutrients in broiler chickens fed barley-based diets. Two experiments (Exp. 1 and 2) were conducted, in which 11-to-33-d-old broilers were assigned to two dietary treatments (with or without amylase at 81 kilo-novo units/kg diet) in a randomized design. Exp. 1 used 353 male broilers and a low-viscosity normal hulled barley, while Exp. 2 utilized 484 female broilers and a normal hulled cultivar of high-viscosity. All diets in both trials were supplemented with phytase and a xylanase and β-glucanase complex. In Exp. 1, amylase tended to improve feed conversion ratio (P < 0.1) and increased AID of CP (P < 0.05) at 33 d of age but had no effect on AID of starch. In Exp. 2, no effects of amylase were observed on growth performance, AID of starch and CP, or relative organ weights. These findings indicate that amylase supplementation can increase CP digestibility of barley-based diets depending on intrinsic grain viscosity, which may improve performance. High starch digestibility observed in diets without amylase explains the lack of enzyme effect and suggests the investigated barleys caused no major detrimental effects to nutrient utilization, although the use of high-viscosity barley in Exp. 2 led to lower AID of starch and CP than Exp. 1. The use of a xylanase + β-glucanase complex likely improved starch utilization, leaving limited room for improvements with amylase for broilers at this age.

Source: Animal Feed Science and Technology

DOI: 10.1016/j.anifeedsci.2025.116568