Response of Bovine Uterine Microbiota to Staphylococcus aureus Infection

Endometritis is a highly prevalent reproductive disorder in cows, causing serious adverse effects on reproductive performance, which brings huge economic losses to the livestock industry. Staphylococcus aureus is detected in a high proportion of endometritis pathogens (alone or in combinations of infections). Uterine microbial composition plays an important role in endometritis.

In order to determine the role of S. aureus in endometritis, we established an endometritis model using this bacterium and utilized metagenomics to detect the structure and function of the bovine uterine microbiota.

We found that S. aureus infection significantly increased the relative abundance of bacteria such as Escherichia coli, Trueperella pyogenes, and Streptococcus spp., while reducing the relative abundance of Akkermansia and Prevotella bacteria. The functions of microorganisms in the uterus are mainly manifested in metabolic levels, including carbohydrate metabolism, amino acid metabolism, energy metabolism, and lipid metabolism processes. The number of genes continues to increase with the duration of S. aureus infection, which disrupts the balance that maintains the bovine uterine flora.

This study provides a descriptive analysis of changes in the uterine microbiota of cows infected with S. aureus, which contributes to a new understanding of uncultured or unidentified pathogenic bacteria.