Growth Performance and Immunity of Broilers Fed Sorghum–Soybean Meal Diets Supplemented with Phytases and Β-Mannanases

Abstract

Most grains and vegetable feedstuffs used in commercial poultry feed contain phytates and polysaccharides—non-starchy chemical structures that are not degraded by digestive tract enzymes. Exogenous enzymes optimize the use of dietary ingredients. This study aimed to determine whether combining β-mannanases (400 g/ton) and phytases in broiler sorghum–soybean diets could improve performance and immunity in broilers. Four diets were randomized in a 2 × 2 factorial design, with two phytase levels (500 or 1500 FTU/kg) and β-mannanase supplementation (0–400 g/ton; 158 million units/kg minimum enzyme activity). Six replicate battery cages of 10 chicks were fed each diet ad libitum. To assess cellular and humoral immune responses, 10 birds per treatment were euthanized on day 21. Supplementation with β-mannanase enzymes led to increased body weight and a higher feed conversion index (FCI) (p p p p p < 0.05). Supplementing broilers with β-mannanases in sorghum–soybean meal diets with phytases improved their performance and immunity.

Keywords

• exogenous enzymes
• broilers
• gut
• sorghum–soybean meal diet