First insight into the faecal microbiota of the high Arctic muskoxen (Ovibos moschatus)

Abstract

The faecal microbiota of muskoxen (n=3) pasturing on Ryøya (69° 33′ N 18° 43′ E), Norway, in late September was characterized using high-throughput sequencing of partial 16S rRNA gene regions. A total of 16 209 high-quality sequence reads from bacterial domains and 19 462 from archaea were generated. Preliminary taxonomic classifications of 806 bacterial operational taxonomic units (OTUs) resulted in 53.7–59.3 % of the total sequences being without designations beyond the family level. Firmicutes (70.7–81.1 % of the total sequences) and Bacteroidetes (16.8–25.3 %) constituted the two major bacterial phyla, with uncharacterized members within the family Ruminococcaceae (28.9–40.9 %) as the major phylotype. Multiple-library comparisons between muskoxen and other ruminants indicated a higher similarity for muskoxen faeces and reindeer caecum (P>0.05) and some samples from cattle faeces. The archaeal sequences clustered into 37 OTUs, with dominating phylotypes affiliated to the methane-producing genus Methanobrevibacter (80–92 % of the total sequences). UniFrac analysis demonstrated heterogeneity between muskoxen archaeal libraries and those from reindeer and roe deer (P=1.0e-02, Bonferroni corrected), but not with foregut fermenters. The high proportion of cellulose-degrading Ruminococcus-affiliated bacteria agrees with the ingestion of a highly fibrous diet. Further experiments are required to elucidate the role played by these novel bacteria in the digestion of this fibrous Artic diet eaten by muskoxen.

Geography, seasonality, and host‐associated population structure influence the fecal microbiome of a genetically depauparate Arctic mammal

“…The Canadian muskox bacterial communities were found to be similar to previous fecal microbiome studies from muskoxen from Norway and Greenland ( n = 3 and 39 individuals, respectively) (Andersen‐Ranberg et al, ; Salgado‐Flores et al, ; Ungerfeld et al, ). The core genus Ruminococcaceae UCG‐005 was also reported in all muskoxen samples from Norway and Greenland, while the other three core genera were present in low abundances and were not shared by all samples (Andersen‐Ranberg et al, ).…”

“…Andersen‐Ranberg et al, () hypothesized the difference in relative bacterial abundances between Eastern Greenland and Norway was due to dietary differences, although the authors did not explicitly test this hypothesis. The diversity indices for muskoxen were congruent with the high gut bacterial diversity of ruminants and conformed to the values seen in Norwegian muskox as well as other ungulates, such as sheep, musk deer, and reindeer (Kittelmann et al, ; Li et al, ; Salgado‐Flores et al, ).…”

“…These phyla are common in herbivorous ungulates due to their roles in fiber and carbohydrate degradation, as well as immune system support in the gastrointestinal tract (Fernando et al, ). Salgado‐Flores et al, () found that the muskox gastrointestinal tract was dominated by Firmicutes and Bacteriodetes with lesser amounts of the phyla Tenericutes and Cyanobacteria . While the two major bacterial phyla were the same, we found our muskox fecal samples to have a low abundance of Tenericutes and Proteobacteria .…”

“…Proteobacteria includes many pathogenic genera, such as the Escherichia , Pseudomonas , and Yersinia genera found within our samples, but it is also symbiotic to the plants that make up the muskox diet and may be naturally found in the intestinal tract (Lock & Wellehan, ). The Ruminococcaceae family composed the majority of the sequences from Firmicutes phyla, and this bacteria family is known to help with digesting highly lignified plant material and made up the majority of the core and common microbiome of muskoxen (Andersen‐Ranberg et al, ; Salgado‐Flores et al, ).…”

“…In mammals, the gastrointestinal microbiome has been shown to be affected by captivity (Li et al, ), kinship (Yuan et al, ), disease (Wasimuddin et al, ), and season (Hu et al, ). More specifically, many comprehensive microbiome studies have been performed on ungulate species because their unique morphological traits impact the gut bacterial composition, and in return, the bacterial composition impacts fitness (Bergmann et al, ; Gruninger, Sensen, McAllister, & Forster, ; Koike, Yoshitani, Kobayashi, & Tanaka, ; Li et al, ; Pope et al, ; Qi et al, ; Salgado‐Flores, Bockwoldt, Hagen, Pope, & Sundset, ). Most ungulates are herbivores that digest cellulose from plant material, including ruminants, which have a chambered stomach and can regurgitate food from their rumen to redigest cud.…”