Ovine Metagenome

The microbes inhabiting the rumen are fundamental to energy metabolism in sheep and other ruminants. These microbial communities are thus of great importance in food production, and also play a major role in global greenhouse gas emissions through methane production. Here, we analyse the rumen bacterial microbiotas of long-tailed Norwegian white sheep and the smaller Nordic short-tailed Spel sheep from three farms located in central Norway, using deep 16S rRNA gene amplicon sequencing. We report fine-scale geographical structuring of microbial communities colonizing sheep stocks. Furthermore, we observed consistent enrichment of several prevalent bacterial taxa between the breed types, in spite of dietary differences between two stocks of the same breed raised on different farms. We further report differences in microbial groups relevant for methane production, as well as significant differences between the bacterial communities associated with rumen digesta particles and the epithelial mucosa. This is, to our knowledge, the first report of breed-level microbiota structuring in a ruminant species. Our results have implications for how we view host adaptation in microbial communities associated with phenotypically distinct animals with similar genetic backgrounds.