Seasonal variations in the composition and functional profiles of gut microbiota reflect dietary changes in plateau pikas

Abstract

Seasonal variations in gut microbiota of small mammals and how they are influenced by environmental variables are relatively poorly understood. We sampled 162 wild plateau pikas (Ochotona curzoniae) in 4 seasons over 2 and a half years and recorded the air temperature, precipitation, and nutrient content in edible vegetation at the sampling site. After conducting 16S rRNA and shotgun metagenomic sequencing, we found that the highest alpha diversity, the relative abundance of Firmicutes, and the simplest co-occurrence network occurred in winter, whereas the highest relative abundance of Proteobacteria and the most complex network structure were observed in spring. The highest relative abundance of Verrucomicrobiota and Spirochaetota was seen in summer and autumn, respectively. Air temperature, precipitation, and the contents of crude protein, crude fiber, and polysaccharide in vegetation had significant effects on the seasonal changes in gut microbiota. Diet contributed more to microbial variation than climatic factors. Metagenomic analysis revealed that the amino acid metabolism pathway and axillary activity enzymes were most abundant in summer, while abundance of carbohydrate-binding modules and carbohydrate esterases was highest in spring. These microbial variations were related to the changes in dietary nutrition, indicating that gut microbiota of plateau pika contribute to the efficient use of food resources. This study provides new evidence of how external environmental factors affect the intestinal environment of small mammals.

Gut Seasons: Photoperiod Effects on Fecal Microbiota in Healthy and Cafeteria-Induced Obese Fisher 344 Rats

“…Hence, as mentioned earlier, only a few studies have focused on investigating seasonal variations of gut bacteria. Moreover, these studies have used non-obese animals and therefore the effects of seasonal variations under an obesogenic context has not been sufficiently investigated yet [ 24 , 25 , 27 , 40 ]. Therefore, we investigated the effect of different photoperiods on gut microbiota composition in both healthy and obese rats and how those changes correlated with parameters related to obesity development such as body weight gain and fat depots accumulation.…”

“…Previous studies indicated that the relative abundance of certain bacteria differed for Siberian hamsters housed in long- versus short-day lengths [ 21 , 23 ]. In addition, seasonal variations in gut bacteria related to dietary changes were found in plateau pikas [ 24 ]. In another study in giant pandas, seasonal oscillations of gut microbiota and higher short chain fatty acid (SCFA) production in the shoot-eating season were observed [ 25 ].…”

The effects of grape seed proanthocyanidins in cafeteria diet-induced obese Fischer 344 rats are influenced by faecal microbiota in a photoperiod dependent manner

“…[19][20][21] In this context, fluctuations in environmental cues, mainly driven by the length of the daylight phase, have been linked to changes in the gut microbiota. [22][23][24] In fact, a study carried out in Siberian hamsters revealed that the intestinal microbiota is responsive to changes in photoperiods. These changes in bacterial abundance were associated with elevated body and fat mass observed in animals housed under long summer-like day length (LD) conditions compared to animals housed under short winter-like day length (SD) conditions.…”

Differences in intestinal microflora of birds among different ecological types

“…Yu et al (2022) demonstrated that there were two gut microbial community types in wild plateau pikas (Ochotona curzoniae), which had different microbial diversity, interactions, and functions. Fan et al (2022) also showed the composition and functional profiles of gut microbiota in plateau pikas varied among seasons, and environmental factors (especially diet) had profound effects on it. Yan et al (2022) found that freeliving wild camels (Camelus ferus) higher energy utilization efficiency compared to that of captive-living counterparts, therefore enable the host to adjust to a relatively barren field environment.…”