Characterization of Bifidobacterium pseudolongum Isolated from Vaginal and Uterine Microbiota of Dairy Cows

Abstract

Bacterial invasion and proliferation in the endometrium of postpartum dairy cows can lead to uterine diseases, including endometritis. Antimicrobials are used to treat endometritis, however, public health concerns about antimicrobial resistance (AMR) have accelerated the exploration for alternative treatment strategies. In this study, we isolated and identified bacteria from the vagina and endometrium of postpartum dairy cows and evaluated them as potential probiotic candidates. Initially, the antimicrobial activity of B. pseudolongum against Escherichia coli and Trueperella pyogenes, known pathogens of endometritis, was assessed using a cross-streaking method. It was found that 30 out of 33 strains were identified as exhibited significant antimicrobial activity. A rapid growth rate was observed in 7 out of 33 strains. Whole-genome analysis revealed that 30 out of 33 strains did not carry transmissible drug-resistance gene and could be systematically classified into three clusters.