The Use of Exogenous Enzymes in Dairy Cattle on Milk Production and their Chemical Composition: A Meta- Analysis

Abstract

We performed a meta-analysis to evaluate the effect of the addition of exogenous enzymes in ruminant feeding on milk production and chemical composition. We analysed the observations of 29 experiments, which included 52 treatments, 9 enzymes, and 1187 animals; with this information, we arranged a comprehensive database. The dose and study were used as experimental approaches. We observed that the addition of enzyme has no effect on the increment in milk yield production (P=0.16), fat content (P=0.88), lactose (P=0.39) or protein (P=0.95). The study showed that the variable milk yield is not a good parameter for determining with respect to the administration of exogenous enzymes (R2=0.001). As a conclusion, it is necessary to reconsider the use of exogenous enzymes in domestic ruminants when the focus is to improve milk production and their chemical composition.