Abstract
The gut microbiome can be one pathway by which a host rapidly acclimates
and adapts to its ecological environment. Exploring how the microbiome
has evolved to differ between hosts with different diets provides
insights into the profound interactions between hosts and microbes
within these systems. In this study, we used DNA metabarcoding
techniques and macrogenomic prediction techniques to study the gut
microbes of four desert rodent species with different feeding strategies
in the same habitat. One species is herbivorous (Spermophilus
alashanicus), one is seed-eating (Phodopus roborovskii), another is
omnivorous (Dipus sagitta), and the last (Orientallactaga sibirica) has
a diet with a relatively high proportion of meat. Diets rich in plants
and insects can be challenging to digest due to the abundance of
indigestible fiber and stable chitin, respectively. Out of the species
studied, the herbivorous Spermophilus alashanicus has the highest
density of UCG-005 genes and the highest predicted abundance of genes
related to digestive complexity. The composition of Phodopus
roborovskii’s microbiome has the highest variation between individuals,
yet Phodopus roborovskii has the highest predicted abundance of genes
associated with simple sugars—reflecting this species’ potential
adaptability to the fiber within plant seeds and its constraints brought
about by its smaller body size. The most insectivorous species,
Orientallactaga sibirica, exhibits the highest predicted abundance of
genes related to chitin degradation. This study has enhanced our
understanding of the gut microbiota in the intestines of rodents as they
adapt to various dietary strategies.