Detection and molecular characterization of BCoVs circulating in central China based on the full-length spike gene

ABSTRACT

Bovine coronavirus (BCoV) is prevalent throughout the world and is an important aetiological agent of diarrhoea in new-born calves. However, little is known about the genetic diversity and molecular epidemiology of BCoV in China. In this study, a total of 127 faecal samples from diarrhoeic dairy calves from nine cities in Henan Province, Central China, were collected between 2017 and 2018 and evaluated by RT-PCR for the N gene. BCoV was detected in 15% (19/127) of calves. In addition, the full-length sequence of the S gene from 13 representative BCoV strains was obtained and analysed. Sequencing results for the full-length S gene showed 97.3-97.5% nucleotide (nt) identity and 96.3-96.8% amino acid (aa) identity with the classical Mebus strain. Phylogenetic analysis based on the full-length S gene showed that the BCoV strains in this study clustered with Vietnamese and Cuban BCoV strains on a large branch of the tree. These results enrich the molecular characterization of the Chinese BCoV strains and provide the first large-scale epidemiological examination of the prevalence of BCoV in diarrhoeic calves in Henan Province, Central China.