Metagenomic Analysis Of Zoonotic Pathogen Microorganisms Carried By Cattle Of Pasture In Xinjiang,China

A large number of microbial species are colonized in the intestinal and respiratory tracts of mammals,which may pose a potential threat to the health of the host itself or infect human beings as potential sources of food and environment as zoonotic pathogens,leading to the spread of diseases and endangers human health.The purpose of this study was to investigate the microbial diversity and potential zoonotic pathogens of cattle in large-scale breeding in Xinjiang,and to provide scientific basis for the large-scale healthy scattle breeding and the prevention and control of zoonotic diseases from cattle,in this study,we selected cattle from large-scale breeding pastures in Kashgar Prefecture of southern region and Shihezi city of northern region in Xinjiang,and carried out relevant investigation by means of metagenomics technology.A total of 303 bovine oropharynx swabs and 306 bovine anal swabs were collected,including 104 bovine oropharynx swabs and 104 bovine anal swabs from Kashgar Prefecture,199 bovine oropharynx swabs and202 bovine anal swabs from Shihezi city,respectively.The whole genome DNA of each sample was extracted for metagenomics analysis.By means of using metagenomic sequencing,the microflora and the potential zoonotic pathogens carried by cattle in this area were comprehensively analyzed by comparing the Mini Krakenv 2 database and analysis of bioinformatics methods.The results showed that the microflora dominated in all cattle samples were bacteria,while viruses could be detected in some samples.A comparative analysis of bacterial communities in different sample types found that the intestinal and respiratory tracts of the cattle were dominated with bacteria and the dominant bacteria of the two sample types were different.Comparative analysis of bacterial communities in all bovine anal swabs and oropharynx swabs revealed that the intestinal and respiratory tracts of the cattles were dominated by Actinomycetes,Proteobacteria,Firmicutes and Bacteroides,while the dominant genera in the two sample categories were different,and the dominant bacterial genera shared by them were Actinoalloteichus and Bacillus.The results of PCo A and ANOSIM analysis showed some similarity between the bacterial communities carried by cattle in Kashgar,South Xinjiang and Shihezi,North Xinjiang,and the differences between groups were bigger than those within groups were statistically significant(P<0.01).The LEf Se difference analysis elucidated that the group differences between both regions of the bovine intestine and respiratory tracts were manifested in the phylum Actinobacteria.In addition,we also found that the virus populations in bovine samples distributed in different regions showed that the differences were statistical significant(P<0.01),and the differences were mainly reflected in bovine gamma herpesvirus 4?bovine gamma herpesvirus 6,etc.A total of nine zoonotic pathogens were found,including Bacillus cereus,Escherichia coli,Streptococcus suis,Streptococcus pneumoniae,Acinetobacter baumannii,Klebsiella pneumoniae,Campylobacter jejuni,Streptococcus pyogenes and Pasteurium multocidum,most of which were food-borne bacterial pathogens.The structure of bacteria/viruses carried in bovine oropharynx and anorectum from large-scale breeding pastures in Xinjiang showed a relatively rich diversity and the pathogens of zoonosis,which were mainly transmitted by foodborne pathogenic bacteria,were detected,posing a certain risk of food safety and disease transmission.