Analysis Of Gut Microflora Structure Of Reindeer Based On 16S RRNA Sequencing

Reindeer is the only animal under artiodactyla,ruminant suborder,deer family and reindeer.It is medium in size,and both male and female have antlers,also known as antlers.Reindeer are mainly distributed in the coniferous forests around the Arctic Circle,where the habitat has poor soil,sparse vegetation and cold climate.They mainly feed on mosses and litmus in the Arctic,as well as mushrooms and twigs of woody plants.Mosses and lichens are indispensable food for reindeer to maintain their survival.Through long-term natural selection,reindeer have evolved many unique biological traits,such as cold tolerance,stress resistance,unique feeding habits,and intolerance to rough feeding.In China,reindeer are mainly distributed in Genhe and its surrounding areas in the northwest of Daxing ’an Mountains.They are in a semi-wild state.They are domesticated by ewenki indigenous hunters for a long time and can be used for service.Intestinal microorganism is a community of microorganisms colonized in the host body,which participates in the regulation of host metabolism,immunity,endocrine and other physiological processes.The composition of intestinal flora is the result of its long-term survival in the habitat,interaction with the environment and evolution.It is closely related to the genetics,feeding habits and development of the host,and plays a key role in maintaining the healthy growth and development of the body.The interaction between intestinal microbiota and host is very complex.A large number of studies on the intestinal microbiota of human and other economic animals have been reported,but there is no relevant study on the structure of the intestinal microbiota of reindeer.Therefore,this paper takes reindeer as the research object,collects its feces and intestinal contents,studies its intestinal flora structure through traditional strain isolation and culture and combined with 16 S rRNA high-throughput sequencing technology,and analyzes the composition characteristics of its intestinal flora,so as to lay a necessary foundation for understanding the correlation between the composition of intestinal flora and the formation of Reindeer’s unique biological behavior and traits.The main results are as follows:1.The diversity of intestinal flora of reindeer is richer than that of other deer,and the composition of the flora is unique.A total of 58 phyla were involved in the intestinal flora of 9 reindeer feces.The core bacteria in phylum,class,order and family were Firmicutes,Bacteroidota and Proteobacteria;Clostridia and Bacteroidia;Bacteroidales,Oscillospirales and Oscillospiraceae.2.The faecal flora structure of reindeer in different habitats was significantly different.There were 1,955 unique ASVs for non-native reindeer in captivity and 5,142 unique ASVs for semi-domestic reindeer in their natural habitat,with 383 ASVs between the two groups.The higher abundance of Firmicutes in the faeces of captive reindeer and the higher abundance of Cyanobacteria in the faeces of semi-domestic reindeer in their natural habitat suggest that the composition of reindeer gut flora is affected by dietary conditions.3.There were significant differences in microflora structure in different parts of alimentary canal of reindeer.The five genera with the highest abundance in reindeer gut contents were Pantoea,Acinetobacter,Unidentified＿Clostridiales,Stenotrophomonas and Erwinia;The five genera with the highest abundance in feces were Chloroplast,UCG-005,Bacteroides,Mitochondria and Rikenellaceae＿RC9＿gut＿group.4.Reindeer gut microbiota composition is affected by the climate and temperature of the habitat.Compared with Cervus eldii living in tropical warm environment,the abundance of Bacteroidetes in reindeer intestinal flora was significantly reduced.The bacteria can metabolize carbohydrates and produce short chain fatty acids such as propionate in the animal body to reduce fat storage,and the abundance of Bacteroidetes decreased or was more conducive to the energy conservation of reindeer in cold environment.In conclusion,through 16 S rRNA sequencing technology combined with various statistical analysis methods,this study clarified the composition characteristics of reindeer intestinal flora,and found that reindeer intestinal flora is rich in diversity,and its composition is significantly affected by diet and climate conditions.These results provide an important basis for revealing the correlation mechanism between the composition of reindeer intestinal flora and its unique feeding habits and cold resistance.