Analysis Of The Gut Microbiota Diversity In Przewalski's Gazelle

In this study,Przewalski's gazelle was used as the test object,and fresh fecal samples of Przewalski's gazelle in the grass-green period and the withering period were collected,and high-throughput sequencing technology was used to investigate the gut microbiota diversity of Przewalski's gazelle in different phenological phases.In this study,a control group of Przewalski's gazelle fed with selenium-deficient feed and a test group of selenium gazelle fed with selenium supplemented feed were also set up.After the feeding,the fecal samples were collected to extract the total DNA for high-throughput sequencing to explore the effect of selenium supplementation on the diversity of gut microbiota of Przewalski's gazelle.The test results were as follows:(1)The gut microbiota of Przewalski's gazelle was dominated by Firmicutes and Bacteroidetes,with a total relative abundance of the two phyla up to 90%,with a large number of unclassified bacteria at the genus level.(2)The Alpha diversity indices(except the Simpson index)of the samples in the grass-green period group was lower than that in the withering period group,and there were significant differences between the two groups in the ACE index and the Chao index(P<0.05);Beta diversity analysis showed that samples of the two groups had significant differences in community composition(P<0.05).(3)The results of taxonomic classification of community showed that the gut microbiota of Przewalski's gazelle in the group of the grass-green period was dominated by Firmicutes,while Bacteroides was the dominant flora in the group of the withering period.(4)The abundance of genes related to Biosynthesis of Other Secondary Metabolites,Metabolism of Cofactors and Vitamins,Glycan Biosynthesis and Metabolism,Amino Acid Metabolism and Metabolism of Other Amino Acids of the samples in the withering period group was significantly higher than that in the grass-green period group(P<0.05)?(5)The Alpha diversity indices(except the Simpson index)of the samples in the test group fed selenium-supplemented feed was higher than that in the control group fed selenium-deficient feed,but the difference was not significant(P>0.05);Beta diversity analysis showed that the samples of the two groups had significant differences in community composition(P <0.05).(6)The relative abundance of Bacteroides and Oscillibacter in the test group was significantly higher than that in the control group(P<0.05),and the abundance of genes related to Carbohydrate transport and metabolism in the gut microbiota was significantly higher than that in the control group(P <0.05).Based on the results of the above test,the following conclusions were drawn:(1)The gut microbiota of Przewalski's gazelle was dominated by Firmicutes and Bacteroidetes,and there was a large number of unclassified bacteria in the gut of Przewalski's gazelle.(2)The gut microbiota composition of Przewalski's gazelle was significantly different in different phenological stages.In the grass-green period,the gut microbiota of Przewalski's gazelle was dominated by Firmicutes,while Bacteroides was the dominant flora in the withering period,and the gut microflora of Przewalski's gazelle was more active in amino acid metabolism,glycan metabolism and synthesis in the withering period.(3)Selenium supplementation showed a tendency to increase the diversity of gut microbiota in Przewalski's gazelle.It could increase the abundance of Bacteroides and Oscillibacter in the gut of Przewalski's gazelle,and up-regulate the expression of genes related to the transport and metabolism of carbohydrates in the gut microbiota.