Background and Objective: Poultry diets are often formulated with corn-derived distillers dried grains and cereal grains. These grains contain higher levels of non-starch polysaccharides (NSPs) which are not digestible by broilers and can increase intestinal viscosity. β-glucan is partially water soluble which in turn causes a gel-like viscosity in the gastrointestinal tract of broilers. This reduces the diffusion rates of substrates and enzymes which leads to reduced nutrient absorption. The addition of glucanase enzymes has been shown to degrade plant cell walls releasing nutrients from grain endosperm while providing a probiotic effect. As a result, glucanases can improve broiler performance by allowing NSPs to be digested and absorbed. This experiment was conducted to evaluate the effects of different inclusion rates of corn-expressed glucanase (AC1) on apparent ileal digestibility (AID) and apparent metabolizable energy (AME). Materials and Methods: Broilers were fed a diet with corn-expressed glucanase enzyme (AC1) at different inclusion rates: Positive Control (PC, no enzyme balanced diet), Negative Control (NC, -100 kcal kg1 ME reduction from PC diet) and NC diets with corn-expressed glucanase added at different inclusion rates, with AC1 added at either 0.18 kg t1, 0.35 kg t1, 0.50 kg t1, 0.75 kg t1, or 2.00 kg t1. At day 28 and 42, intestinal contents were collected from the ileum of 48 birds/trt. On d28, samples were analyzed for ileal digestibility and on day 42 samples were analyzed for AME and AME corrected for nitrogen. Results: Ileal digestibility was improved or equal to the PC and better than the NC in broilers fed AC1 at rates 0.35 kg t1 and higher for Ca and P digestibility (p<0.05). Both AME and AMEn were improved in broilers fed AC1 at rates of 0.35 kg t1 and higher when compared to the NC. The AMEn was equal in the PC and AC1 fed at 2.00 kg t1. Conclusion: Feeding AC1 at rates greater than 0.35 kg t1 increases calcium and phosphorus digestibility and can return AME/AMEn to normal levels in diets with -100 kcal kg1 ME reductions. This could lead to improved feed efficiency and bone strength in broilers which could lead to improved performance and welfare.
A.T. Dimas, E.B. Sobotik, G.M. House, A.M. Stiewert, P. Lessard and G.S. Archer, 2023. Effect of Corn-Expressed Glucanase on Mineral Digestibility and Apparent Metabolizable Energy in Broiler Diets. International Journal of Poultry Science, 22: 12-16.