SummaryThe objective of this research was to compare the composition of bacterial microbiota associated with the ruminal content (RC), ruminal epithelium (RE) and faeces of Holstein dairy cows. The RC, RE and faecal samples were collected from six Holstein dairy cows when the animals were slaughtered. Community compositions of bacterial 16S rRNA genes from RC, RE and faeces were determined using a MiSeq sequencing platform with bacterial‐targeting universal primers 338F and 806R. UniFrac analysis revealed that the bacterial communities of RC, RE and faeces were clearly separated from each other. Statistically significant dissimilarities were observed between RC and faeces (P = 0.002), between RC and RE (P = 0.003), and between RE and faeces (P = 0.001). A assignment of sequences to taxa showed that the abundance of the predominant phyla Bacteroidetes was lower in RE than in RC, while a significant higher (P < 0.01) abundance of Proteobacteria was present in RE than in RC. When compared with the RC, the abundance of Firmicutes and Verrucomicrobia was higher in faeces, and RC contained a greater abundance of Bacteroidetes and Tenericutes. A higher proportions of Butyrivibrio and Campylobacter dominated RE as compared to RC. The faecal microbiota was less diverse than RC and dominated by genera Turicibacter and Clostridium. In general, these findings clearly demonstrated the striking compositional differences among RC, RE and faeces, indicating that bacterial communities are specific and adapted to the harbouring environment.
To evaluate lactation performance and changes in plasma and fecal lipopolysaccharide (LPS) concentrations in response to the supplementation of Saccharomyces cerevisiae fermentation product (SC), two dairy farms were selected. On each farm, 32 cows in early to mid lactation (21 to 140 DIM) were blocked by parity and days in milk (DIM), and randomly assigned to one of the two treatments within block (Control or 56 g SC/cow/d). Effect of SC on lactation performance (daily) and changes in blood and fecal LPS level were examined on d 0 and 28 of supplementation. The results showed that SC supplementation increased lactation performance of dairy cows on both farms. On Farm 1, milk production, 3.5% fat corrected milk (FCM), and yield of milk fat and protein were greater (p<0.01) for cows supplemented with SC. Supplementation of SC increased percentage milk fat (p = 0.029) from 81 to 110 DIM. There was no significant effect (p>0.05) of SC supplementation on percentage of milk protein, dry matter intake and feed efficiency. On Farm 2, cows supplemented with SC had a greater (p<0.05) milk yield, percentage of milk fat and milk protein, yield of milk fat and protein, 3.5% FCM and feed efficiency. Supplemental SC had no effect on LPS concentrations in feces (p>0.05) while it trended to reduce (p = 0.07 or 0.207) the concentration in plasma. The results indicate that supplemental SC can increase lactation performance of dairy cattle and has potential for reducing plasma LPS concentration.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.