Effect of various dietary enzymes on energy digestibility of diets high in distillers dried grains with solubles for broilers

Abstract

Two trials of similar experimental design were conducted to assess the effects of various dietary enzymes on energy digestibility of diets high in distillers dried grains with solubles (DDGS) for broilers. A 2 × 4 factorial arrangement of treatments was used in which a corn- soybean meal control diet and a diet with 30% DDGS were supplemented with 2 different commercial enzyme products. In addition to the unsupplemented control, each enzyme was fed at the level suggested by the manufacturer, twice the recommended level, and 4 times the recommended level. Allzyme SSF (Alltech, Nicholasville, KY) was used in the first experiment, and Rovabio Excel (Adisseo, Alpharetta, GA) was used in the second experiment. Male commercial strain chicks that were 15 (trial 1) or 20 (trial 2) d old were randomly assigned to the experimental diets, with each treatment replicated 3 times. Celite (Celite Corp., Santa Barbara, CA) was used as an indigestible marker. After a 5-d period of acclimation to the diets, excreta samples were collected. The energy contents of the diet and excreta were determined and digestibility of dietary energy was calculated. In both trials, there was a significant (P < 0.05) difference in gross energy digestibility between the corn-soybean meal control diets and diets with 30% DDGS. However, no significant improvement in gross energy digestibility was obtained by adding any level of the 2 enzymes. Moreover, no significant interactions were found between the basal diets and various enzyme levels. Therefore, addition of the enzymes used in these studies had no apparent beneficial effect on energy digestibility of corn-soybean meal diets or diets with a high level of DDGS.