Prevalence of bovine astroviruses and their genotypes in sampled Chinese calves with and without diarrhoea

• Published in: Journal of general virology 2021-08, Vol.102 (8)
• Main Authors: Zhu, Jie, Qi, Mingpu, Jiang, Chuanwen, Peng, Yongchong, Peng, Qingjie, Chen, Yingyu, Hu, Changmin, Chen, Jianguo, Chen, Xi, Chen, Huanchun, Guo, Aizhen
• Format: Article
• Language: English
• Subjects: Animal
• ISSN: 0022-1317; 1465-2099
• DOI: 10.1099/jgv.0.001640

Bovine astrovirus (BoAstV) belongs to genus Mamastravirus (MAstV). It can be detected in the faeces of both diarrhoeal and healthy calves. However, its prevalence, genetic diversity, and association with cattle diarrhoea are poorly understood. In this study, faecal samples of 87 diarrhoeal and 77 asymptomatic calves from 20 farms in 12 provinces were collected, and BoAstV was detected with reverse transcription-polymerase chain reaction (RT-PCR). The overall prevalence rate of this virus in diarrhoeal and asymptomatic calves was 55.17 % (95 % CI: 44.13, 65.85 %) and 36.36 % (95 % CI: 25.70, 48.12 %), respectively, indicating a correlation between BoAstV infection and calf diarrhoea (OR=2.15, P =0.024). BoAstV existed mainly in the form of co-infection (85.53 %) with one to five of nine viruses, and there was a strong positive correlation between BoAstV co-infection and calf diarrhoea (OR=2.83, P =0.004). Binary logistic regression analysis confirmed this correlation between BoAstV co-infection and calf diarrhoea (OR=2.41, P =0.038). The co-infection of BoAstV and bovine rotavirus (BRV) with or without other viruses accounted for 70.77 % of all the co-infection cases. The diarrhoea risk for the calves co-infected with BoAstV and BRV was 8.14-fold higher than that for the calves co-infected with BoAstV and other viruses (OR=8.14, P =0.001). Further, the co-infection of BoAstV/BRV/bovine kobuvirus (BKoV) might increase the risk of calf diarrhoea by 14.82-fold, compared with that of BoAstV and other viruses (OR=14.82, P