Yeast and enzyme supplementation in the diet for lactating buffalo: in vivo and in vitro evidence

Abstract Background Yeast cultures and exogenous enzymes are widely used as feed additives in ruminant nutrition, particularly in dairy cattle, due to their beneficial effects on rumen fermentation, nutrient degradability, and animal performance. However, information on their application in buffalo nutrition remains limited, and most available knowledge is extrapolated from studies conducted in cattle. Therefore, the present study aimed to evaluate the combined effects of yeast cells and enzymes on lactating multiparous buffaloes’ performance, as well as their influence on ruminal fermentation characteristics. Methods To achieve this objective, an eight-week in vivo trial on Italian Mediterranean Buffalo cows and an in vitro rumen fermentation using buffalo ruminal fluid were performed. Parameters evaluated included diet chemical composition and in vitro fermentation characteristics, milk yield and composition, fecal composition and volatile fatty acids (VFA) and blood biochemical metabolites. Results In vivo results showed that, buffaloes receiving the yeast-enzyme supplement exhibited improve milk fat ( p < 0.001), protein ( p < 0.001) and casein ( p < 0.05) content and the production of energy corrected milk ( p < 0.01). Fecal analyses revealed a lower starch ( p < 0.05) content and differences in acetate and total VFA concentrations in the supplemented group. Blood biochemical analyses further showed higher glucose ( p < 0.001), lower blood urea nitrogen ( p < 0.001) and triglyceride ( p < 0.05) at the end of the trial. Conversely, in vitro fermentation results exhibited greater VFA production in the non-treated group ( p < 0.001), whereas faster fermentation kinetics in the treated group. Conclusions These results support the use of microbial and enzymatic feed additives as a promising nutritional strategy for modulating the composition of milk, particular blood biochemical parameters, and rumen fermentation characteristics of lactating buffaloes, thereby supporting the need for further study of these additives as a nutritional strategy in buffalo dairy production.