Microbiota in Goat Buck Ejaculates Differs Between Breeding and Non-breeding Seasons

Area of Science:

• Animal Science
• Microbiology
• Reproductive Biology

Background:

• Semen microbiota alterations are linked to sperm quality and fertility.
• Goats are seasonal breeders, but their semen microbiota and seasonal effects remain unstudied.

Purpose of the Study:

• To characterize the ejaculates' microbiota in goat bucks.
• To determine if semen microbiota composition differs between breeding and non-breeding seasons.

Main Methods:

• Semen samples were collected from six Murciano-Granadina bucks across breeding and non-breeding seasons.
• Microbiota was analyzed using genomic sequencing technology.
• Sperm quality parameters, including motility and apoptosis, were evaluated.

Main Results:

• Sperm velocities were higher, and apoptotic spermatozoa proportions differed between seasons.
• Dominant bacterial phyla included Firmicutes, Proteobacteria, Fusobacteria, Actinobacteria, and Bacteroidetes (breeding) and Firmicutes, Proteobacteria, Actinobacteria, Bacteroidetes, and Cyanobacteria (non-breeding).
• The genus *Ureaplasma* dominated both seasons, with significant shifts in *Faecalibacterium*, *Sphingomonas*, and *Halomonas* abundances between seasons. *Sphingomonas* and *Faecalibacterium* correlated with sperm quality.

Conclusions:

• Goat buck semen microbiota composition varies significantly with reproductive seasonality.
• Microbiota composition remained stable within a 7-day period within a season.
• *Sphingomonas* and *Faecalibacterium* show potential as biomarkers for goat semen quality.