title: Molecular epidemiology and phylogenetic analysis of diverse bovine astroviruses associated with diarrhea in cattle and water buffalo calves in China.
abstract: Astroviruses are the principal causative agents of gastroenteritis in humans and have been associated with diarrhea in other mammals as well as birds. However, astroviral infection of animals had been poorly studied. In the present study, 211 rectal swabs collected from cattle and water buffalo calves with mild to severe diarrhea were tested for bovine astrovirus (BAstV) by RT-PCR. Results: 92/211 (43.6%) samples were positive for BAstV, at a rate of 46.10% (71/154) in cattle and 36.84% (21/57) in water buffalo. Phylogenetic analysis based on the partial and full-length of 25 ORF2 amino acid sequences obtained in this study classified the Guangxi BAstVs isolates into five subgroups under the genus of Mamastrovirus, genotype MAstV33, which suggested that the water buffalo was a new host of this genogroup that previously included only cattle and roe deer. Despite the origin of the host, the Guangxi BAstV isolates were closely related to the BAstV Hong Kong isolates (B18/HK and B76-2/HK), but highly divergent from the BAstV NeuroS1 isolate previously associated with neurologic disease in cattle in the U.S.A. Nucleotide sequence-based characterization of the ORF1b/ORF2 junction and corresponding overlapping regions showed distinctive properties, which may be common to BAstVs. Our results suggested that cattle and water buffalo are prone to infection of closely related astroviruses, which probably evolved from the same ancestor. The current study described astroviruses in water buffalo for the first time and is thus far among the largest epidemiological investigations of BAstV infection in cattle conducted in China.
authors.affiliation: Laboratory of Animal Infectious Diseases Prevention and Molecular Immunology, Guangxi University, Daxue Road 100, Nanning, Guangxi 530004, China.
authors.forename: Niyokwishimira
authors.initials: N
authors.lastname: Alfred
authors.forename: Huan
authors.initials: H
authors.lastname: Liu
authors.forename: Mu Lan
authors.initials: ML
authors.lastname: Li
authors.forename: Shao Feng
authors.initials: SF
authors.lastname: Hong
authors.forename: Hai Bo
authors.initials: HB
authors.lastname: Tang
authors.forename: Zu Zhang
authors.initials: ZZ
authors.lastname: Wei
authors.forename: Ying
authors.initials: Y
authors.lastname: Chen
authors.forename: Fa Kai
authors.initials: FK
authors.lastname: Li
authors.forename: Yi Zhi
authors.initials: YZ
authors.lastname: Zhong
authors.forename: Wei Jian
authors.initials: WJ
authors.lastname: Huang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D019200:Astroviridae / Q000235:genetics* / Q000472:pathogenicity; D001483:Base Sequence; D002020:Buffaloes / Q000821:virology*; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000821:virology*; D002681:China / Q000453:epidemiology; D016000:Cluster Analysis; D017931:DNA Primers / Q000235:genetics; D003967:Diarrhea / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D017720:Molecular Epidemiology / Q000379:methods*; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics; D010802:Phylogeny; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D013045:Species Specificity
chemical_list: D017931:DNA Primers