Comparison of the gut microbiota of Rana amurensis and Rana dybowskii under natural winter fasting conditions

ABSTRACT Rana amurensis and R. dybowskii occupy similar habitats. As temperatures decrease with the onset of winter, both species migrate to ponds for hibernation. Our goal was to determine whether different species possess different intestinal microbiota under natural winter fasting conditions. We used high-throughput Illumina sequencing of 16S rRNA gene sequences to analyse the diversity of intestinal microbes in the two species. The dominant gut bacterial phyla in both species were Bacteroidetes, Proteobacteria and Firmicutes. Linear discriminant analysis (LDA) effect size revealed significant enrichment of Proteobacteria in R. amurensis and Firmicutes in R. dybowskii. There were significant differences in the gut microbiota composition between the species. The core operational taxonomic unit numbers in R. amurensis and R. dybowskii shared by the two species were 106, 100 and 36. This study indicates that the intestinal bacterial communities of the two frog species are clearly different. Phylum-level analysis showed that R. amurensis was more abundant in Proteobacteria and Verrucomicrobia than R. dybowskii was This is the first study of the composition and diversity of the gut microbiota of these two species, providing important insights for future research on the gut microbiota and the role of these bacterial communities in frogs.