Correlation between microbial characteristics and reproductive status of the yak uterus based on macrogenomic analysis

This study aimed to investigate the microbial characteristics of yak uteri collected using intrauterine cotton swabs (CS) during different reproductive stages and the correlation of these microbial characteristics with reproductive status. We used a macrogenomic approach to analyze the functional aspects of different microorganisms in samples collected during the pre-estrus, estrus, late estrus, and diestrus stages. The results revealed the presence of 1293 microbial genera and 3401 microbial species in the uteri of yaks at different reproductive stages. The dominant bacterial species varied across the different periods, with Micrococcus and Proteus being dominant during pre-estrus; Pseudomonas, Clostridium, Flavobacterium, Bacillus, and Staphylococcus during estrus; Acinetobacter, Bacillus and Proteus during late estrus; and Pseudomonas, Escherichia coli, and Proteus during diestrus. The primary functions of these bacteria are enriched in various metabolic pathways, including carbohydrate and amino acid metabolism, intracellular transport and secretion, post-translational protein modification, and drug resistance. These findings suggest that the microbial diversity in the uterus of yaks plays a crucial role in reproductive regulation and can help prevent reproductive tract-related diseases.