Effects of Supplementation with Saccharomyces cerevisiae and Its Fermentation Products on Production Performance and Its Mechanism in Perinatal Dairy Cows

The aim of this study was to investigate the effects of Saccharomyces cerevisiae and its fermentation products on performance, blood hormone levels and rumen floral composition in peripartum dairy cows. Sixty perinatal cows were selected and allocated to two groups according to parity and expected date of delivery. Each group was supplemented with Saccharomyces cerevisiae and its fermentation product 0 or 100 g. The results showed that Saccharomyces cerevisiae and its fermentation products could significantly increase the feed intake of peripartum dairy cows (P β-hydroxybutyrate (P = 0.01), reducing the insulin content (P = 0.02). Saccharomyces cerevisiae reduced the abundance of rumen microbes in peripartum dairy cows but had no effect on rumen microbial diversity. Compared with the control group, the supplemented group showed reductions in the abundance of genera Bacillus (P = 0.03), Butyrivibrio (P = 0.01), Denitrobacterium (P = 0.01), and Mogibacterium (P Porphyromonas (P = 0.05), Saccharofermentans (P Sphaerochaeta (P = 0.02), Streptococcus (P = 0.04) and other genera. There were significant increase in the content of Acidaminococcus (P = 0.03), Allisonella (P Bulleidia (P Corynebacterium (P = 0.01), Dialister (P Faecalibacterium (P = 0.02), Faekalitalea (P = 0.03), Fibrobacter (P = 0.04), Flavobacterium (P = 0.03), Kandleria (P Paraprevotella (P Pyramidobacter (P = 0.05), Roseburia (P Succinivibrio (P The main metabolic pathways such as tryptophan metabolism and steroid hormone biosynthesis in perinatal dairy cows were determined for Saccharomyces cerevisiae and its fermentation products.