Metagenomic Analysis of Calf Intestinal Viral Population in Daqing Region
[Objective]The experiment was aimed to comprehend the composition and genetic variability of calf intestinal viruses within the dairy cattle population in the Daqing region,and furnish a theoretical framework for the detection of viral pathogens responsible for diarrhea in local calves.[Method]A total of 155 fecal samples of calves were collected from dairy farms surrounding Daqing,which were divided into six diarrhea sample pools and three clinically asymptomatic sample pools.Total nucleic acid was extracted,high-throughput sequencing was performed based on Illumina sequencing platform,SPAdes and SOAPdenovo were used for sequence splicing and assembly,and viral population composition and genetic variation were analyzed according to the obtained sequences.[Result]A total of 6 517 147 viral-related sequences from 21 viral families were successfully annotated.In the calf intestinal viral community,except for bacteriophaes,Coronaviridae exhibited the highest abundance,followed by Picornaviridae.Comparison of annotation results of the diarrhea samples with asymptomatic samples,the diversity of the virus population in the asymptomatic samples was significantly higher than that in the diarrhea samples,and it was found that the relative abundance of Parvoviridae,Picornaviridae and Reoviridae was higher in the diarrhea group samples compared to the non-diarrhea group.This study annotated multiple novel sequences of calf diarrhea viruses such as Bovine torovirus(BToV),Bovine kobuvirus(BKV)and Bovine norovirus(BNoV).In addition,for the first time,Bovine nebovirus was identified in calf feces in Heilongjiang region.Genetic evolution analysis on the assembled genomes of BRV,BCoV and Bo Ast V was conducted,and it showed that the predominant genotypes of BRV were identified as G6,G10,P[5]and P[11].The assembled full-length genome of BCoV showed the closest phylogenetic relationship with Coronavirus/Bo/BCoV6/2021/CHN,a prevalent strain in China.BoAstV sequences clustered consistently within the branch of enteric tissue tropism strains.[Conclusion]The abundance of Coronaviraceae was the highest in the calf enterovirus population in Daqing area.The abundance of viral population in the diarrhea group samples was lower than that in the non-diarrhea group samples.Several calf diarrhea viruses,such as BToV,BKV and BNoV were annotated in the fecal samples.Additionally,BNeV was first annotated in calf feces from Heilongjiang province.Genetic evolution characteristics of local prevalent viruses such as BRV,BCoV and BoAstV were analyzed.These findings provided a theoretical basis for the detection of viral pathogens causing diarrhea in local calves.
万方数据
维普
