Cattle that eat the same feed and come from the same environment can emit methane (CH4), a potent greenhouse gas, at vastly different levels. An estimated 32% of anthropogenic CH4 can be traced to ‘enteric fermentation’ in livestock production. During enteric fermentation, specialized microorganisms will digest complex plant fiber to create compounds like acetate and hydrogen (H2). Some of these organisms, called methanogens, will consume and use these products to produce CH4. Emerging data suggests natural inter-animal variation in CH4 emissions could derive from host genetics or differences in rumen microbial digestion. Here, we will analyze 16S rRNA gene amplicon sequencing from rumen microbiomes to look for differences in the structure and composition of microbial communities from the rumen of twenty beef cattle of varying CH4 emission levels. There is no significant difference in microbial community diversity by CH4 emission level. We will analyze microbial community structure and composition to identify microbial taxa associated with high and low CH4 emissions. The findings of our work will begin to explain why some cattle emit higher methane levels compared to others, and may aid in finding solutions to reduce methane emissions in cattle while keeping their feeding efficiency and meat production high.
