Digestibility of phosphorus by broiler chickens fed raw and autoclaved faba bean diets with and without phytase.

Abstract

1. The nutritional potential of Faba bean (Vicia faba L.) is limited by the presence of phytate, which reduces phosphorus (P) digestibility and the bioavailability of other minerals. This study evaluated the effect of autoclaving and phytase on the P digestibility of broiler chickens.2. Diets were formulated to include faba beans (FB) or autoclaved FB (AFB), with or without 1,000 FYT/kg phytase, in a 2 × 2 factorial arrangement. Broiler chickens were fed a similar starter diet until d 18, after which 256 chickens were weighed and assigned to four diets in a randomised complete block design, with body weight as the blocking factor (eight replicates of eight birds per cage).3. Phytase increased the apparent total tract digestibility of P (p < 0.01), with an interaction between autoclaving and phytase on AID of P (p < 0.01); the AID of P increased to a greater extent when phytase was added to non-autoclaved FB than to autoclaved FB. Additionally, ileal digestible P and retainable P intake increased with phytase supplementation (p < 0.01).