A Longitudinal Characterization of the Seminal Microbiota and Antibiotic Resistance in Yearling Beef Bulls Subjected to Different Rates of Gain
Emily M. Webb, Devin B. Holman, Kaycie N. Schmidt, Matthew S Crouse, Carl R Dahlen, Robert A. Cushman, Alexandria P Snider, Kacie L McCarthy, Samat Amat
Abstract
Increasing evidence from human and other animal species supports the existence of a commensal microbiota in semen and that this seminal microbiota may influence not only sperm quality and fertility but also female reproduction. Seminal microbiota in bulls and its evolution and factors shaping this community, however, remain largely underexplored. In this study, we characterized the seminal microbiota of yearling beef bulls and its response to the bull age, different weight gains, and mating activity. We compared bacterial composition between seminal and fecal microbiota and evaluated the diversity of culturable seminal bacteria and their antimicrobial resistance. Our results obtained from sequencing, culturing, and antibiotic susceptibility testing provide novel information on the taxonomic composition, evolution, and factors shaping the seminal microbiota of yearling beef bulls. This information will serve as an important basis for further understanding of the seminal microbiome and its involvement in reproductive health and fertility in cattle.