The Elk Rumen: An Ecosystem of Undiscovered Prokaryotes

Microorganisms from elk were sampled in order to understand the symbionts within elk digestive tracts. Bacteria and archaea play crucial roles in rumens by enzymatically degrading plant compounds and producing vitamins and metabolites that are used by the host. Without such microbial life, elk would not be able to digest the plants they depend upon for sustenance. Fecal pellets were used to discover the microorganisms present in elk rumens. DNA extracts from the pellets were subjected to PCR to amplify the microbial ribosomal DNA. Species were separated using a technique to generate “fingerprints” of the microbial communities within each host elk. Trends were seen between the time of year (i.e., plants available for consumption) and between individual elk sampled. Bacterial diversity patterns differed for three animals at four times of the year, with one animal displaying a remarkably stable gut microflora (Elk #67) and the other two varying more distinctly (Elk # 2 and 49). Archaeal species were less abundant in the animals, but were identified to be methanogens, microbes that produce methane gas. Species found in this study were related to other known ruminant microorganisms, but this is the first study that included repeated sampling of wild animals.