Comparative efficacy of commercial phytases on phosphorus availability for broilers.

Abstract

The presence of phytate in broiler diets restricts phosphorus availability, a crucial nutrient for muscle and bone development, leading to reduced performance. To alleviate this issue, exogenous enzymes such as phytase are introduced; however, the wide variety of phytases available on the market and their effectiveness are not yet fully understood. The objective of this study was to evaluate the phosphorus equivalence of commercial phytase in broiler diets, using the standard curve, and its effects on performance, bone mineralization, intestinal histological integrity, liver relative weight, and total alkaline phosphatase in the initial phase (1 to 21 days) of broiler. We used 2,500 male broiler chickens, with an initial weight of 44 g, distributed in a completely randomized design with 10 treatments and 10 replications of 25 birds per experimental unit. The diets were formulated to meet the nutritional requirements of the birds, except for the available phosphorus (Pd) and calcium content. The treatments were divided as follows: T1-Control (CT) with 0.18% Pd; T2-CT + 0.07% aP; T3-CT + 0.14% aP; T4-CT + 0.21% aP; T5-CT + phytase 1; T6-CT + phytase 2; T7-CT + phytase 3; T8-CT + phytase 4; T9-CT + phytase 5; and T10-CT + phytase 6. For enzymatic standardization, 500 FTU/kg (Phytase Units) of each enzyme were used. Animals subjected to the highest levels of P (T2, T3, and T4) and with the addition of commercial phytases (T5, T6, T7, T8, T9, and T10) had better performance and bone mineralization results when compared to T1-CT. All phytases evaluated improved final live weight, weight gain, feed conversion, and ash and phosphorus content in the tibia and intestinal development compared to CT. Supplementing broiler diets with commercial phytases enhances performance, bone mineralization, and jejunal development from 1 to 21 days.The average phosphorus availability from phytic acid in these phytases was 0.154%. The comparison of the six commercial phytases in diets for broiler chickens, using the standard curve and supplementation with 25 g/t of commercial phytase, showed similar results, promoting improvements in performance, bone mineralization, and jejunal development.