PSII-10 Dynamic changes of the fecal bacterial community in dairy cows from early to mid-lactation

Abstract

Abstract The dynamics of the community structure and activity of the dairy cow fecal bacterial communities，therefore this study was conducted to characterize the fecal bacterial communities during gestation and lactation unclear. Here we aimed to characterize the fecal bacterial communities in dairy cows from early to mid-lactation. Feces were sampled from 20 healthy fresh Holstein dairy cows on day 1 (Fresh1d group) and day 14 (Fresh1d group) in milk, and from 10 mid-lactation dairy cows (mid group) from 45 to 60 days in milk (55.96 ± 6.51 days in milk). The early and mid-lactation ration was fed to fresh and mid-lactation cows. The relative abundance of microbial populations and operational taxonomic units revealed significant differences between the different lactation groups (P < 0.05). The relative abundance of Ruminococcaceae_UCG-005 (P < 0.01) and Rikenellaceae_RC9_gut_group (P = 0.02) increased, while that of Christensenellaceae_R-7_group (P < 0.01) decreased as lactation progressed. Especially, low abundance of Bacillus, Escherichia-Shigella, Klebsiella and Streptococcus were detected in mid-lactation cows, this decreased further as lactation progressed, suggesting higher risk of these pathogenic infection during early lactation. Moreover, the relative abundance of predicted microbial genes involved in membrane transport, carbohydrate metabolism and amino acid metabolism were enriched, indicating an increase in the fermentation ability of hindgut microbiota as lactation progressed. Our study provides improved understanding of the dynamic composition and functional variation of the fecal microbiome from early to mid-lactation in dairy cows. The findings support the potential for microbial manipulation of the hindgut microbial community in dairy cows enabling the mitigation of environmental problems associated with dairy cows rearing and manure management.