Seasonal Variation In Intestinal Microbiota Composition Of Chipmunk

Chipmunks(Tamias sibiricus)are small mammals with hibernating habits.They live in distinct environments and have different food resources.The composition of the intestinal microbiota of chipmunks may change with the changes in food.At present,there are almost no reports on intestinal microbiota of chipmunks.It is hoped that we can understand the composition of the intestinal microbiota of chipmunks and its seasonal changes,and enrich the understanding of nutritional ecology of chipmunks.In spring,summer and autumn of 2017,we captured 10 chipmunks in each season and 30 live chipmunks in Liangshui National Nature Reserve of Heilongjiang Province.The fecal samples of captured chipmunks were collected in the laboratory of the reserve and released to the captured area after collection.The collected fecal samples were sequenced by 16S rRNA high throughput sequencing.According to the results of sequencing,we first described the composition of intestinal microbiota of chipmunk,and then analyzed the seasonal changes of intestinal microbiota of chipmunk.Finally,we concluded that the seasonal changes of intestinal microbiota of chipmunk were related to food changes.The main results are as follows:1.A total of 3062 OTUs were obtained from all samples,2894,3425 and 3384 OTUs were obtained from three groups of samples respectively.We found 11 phyla,21 classes,35 orders,75 families and 134 genera in all samples.2.From the composition of the intestinal microbiota of chipmunks,Firmicutes,Bacteroidetes and Proteobacteria are the main dominant microbiota of chipmunks intestinal microbiota;Lactobacillaceae,Enterobacteriaceae,and S24-7 are the dominant families;Lactobacillus is the dominant genus 1.3.The intestinal microbiota composition of chipmunks has a significant difference in different seasons.At phylogenetic level,Proteus increased significantly from spring to autumn(df=18,t=-3.369,F=4.127,P=0.003).At the family level,Lactobacillaceae and S24-7 are the dominant families in spring,while Enterobacteriaceae,S24-7,Lactobacilli,and Ruminococcaceae are the dominant families in suumer and autumn.Among them,Lactobacilliaceae decreased significantly from spring to summer and autumn(df=18,t=3.244,F=1.882,P=0.005;df=18,t=2-766,F=1.688,P=0.013).Enterobacteriaceae increased significantly from spring to autumn(df=18,t=-3.400,F=3.739,P=0.003)At genus level,except for all unclassified genera,the dominant genus was Lactobacillus,which decreased significantly from spring to summer and autumn(df=18,t=3.244,F=1.882,P=0.005;df=18,t=2.766,F=1.688,P=0.013).4.Alpha diversity analysis showed that the diversity of chipmunks intestinal microbiota was the highest in summer.PCA analysis showed that autumn had the highest similarity,and NMDS analysis showed that the composition of chipmunks intestinal microbiota was more similar in spring and summer.