Abstract

North American moose (Alces alces) are experiencing dramatic population declines in the southern portions of their range in the United States. Recent surveys of northeast Minnesota suggest a 52% population decline from 2006 to present. Researchers have suggested the declines in Minnesota’s moose are health related, including diseases, parasites, and undernutrition. Moose in captivity are also experiencing nutritional problems, including weight loss, gastritis, and diarrhea. Despite the vital role the rumen microbial community plays in host nutrition, few studies have examined microbial colonization along the entire gastrointestinal tract (GIT) in these sensitive populations. To characterize the microbiomes of wild Minnesota moose, we opportunistically collected samples (rumen, reticulum, omasum, abomasum, small intestine, colon, feces) from each of 12 moose that died in 2014, four of which were cachectic. The microbial community membership and diversity were analyzed with Illumina amplicon sequencing of the V4 region of the 16S rRNA gene. These samples were compared to the entire GIT microbiome from three Columbus Zoo moose calves experiencing gastritis and diarrhea prior to death. Our preliminary data suggest that the rumen microbiome of both wild and captive moose in poor nutritional condition is distinct from that of moose in a normal weight range. The microbial community colonizing the rumen tissue of both wild and captive cachectic moose from different regions shares the dominance of a single bacterial taxon (Neisseriales). This taxon is found in low proportions in the healthy moose rumen and may represent a microbial bioindicator for assessing nutritional status of wild and captive moose.