Effects of Varying Nutrient Profiles and Enzyme Supplementation in Broiler Diets on Growth Performance and Energy Digestibility

The current research program was designed to evaluate the impact of various dietary and ingredient nutrient profiles and exogenous enzyme inclusion on growth performance and energy utilization in broilers. Experiment one was designed to observe increasing levels of distillers? dried grains with Solubles (DDGS) and a non-starch polysaccharide degrading enzyme (NSPase) on energy digestibility. Experiment two evaluated the influence nutrient variation in corn and xylanase supplementation on growth performance and nutrient utilization.

In experiment one, DDGS concentration was increased from 0 to 15% in 5% increments and included the addition of an NSPase enzyme. Early broiler body weight and FCR was negatively affected with increasing DDGS concentration up to 15%. The decreased growth performance was associated with a decrease in energy and nitrogen utilization as a linear decrease was observed in IDE, INDC, and AMEn. Addition of the NSPase negated many of the negative effects on nutrient utilization as improvements in all digestibility measurements were observed. Interactions were observed with DDGS concentration and NSPase inclusion as the benefit of enzyme inclusion was augmented as DDGS level increase.

Experiment two evaluated different corn crops from six geographical locations in the US in an effort to determine the effects of xylanase inclusion and corn nutrient variation on growth performance and nutrient utilization. Significant differences were observed in growth performance, IDE, and AMEn in broilers when fed corn. Corn source impacted early body weights, and FCR throughout the experiment. Energy utilization was also impacted on all measured parameters, following the starter phase (day 17) and at the conclusion of the trial (day 41) by corn source. Xylanase inclusion improved FCR during the finisher phase as well as the cumulative FCR (day 1-41). Digestibility data indicates that corn source impacts the xylanase effectiveness in young broilers, as improvements were not observed in all corn types. Xylanase inclusion, however, did increase IDE and AMEn in all corn sources on day 41 of age.

Data from this research program confirm that ingredient nutrient content, through the presence of ingredients with anti-nutritive properties or the incidence of varying nutrient profiles, does impact observed growth performance as related to reduced nutrient digestibility. Additionally, the inclusion of a dietary exogenous enzyme does improve energy and nitrogen digestibility in broilers, ultimately improving growth performance of broilers and improving efficiency.