ABSTRACT
Bovine diarrhea is a multi-factorial disease, and remains one of the most serious health problems in cattle husbandry. However, the endemic trends of the main pathogens responsible for bovine diarrhea have not been analyzed before, therefore, the purpose of this study was to estimate the prevalence of bovine diarrhea pathogens in the large-scale cattle farms of Inner Mongolia in China, we assessed the differences in the prevalence of infection based on age and area, as well as determined local prevalence rates and the rates of mixed infections. Using stratified random sampling strategy, cattle were divided into four age stages (0-2 months, 3-6 months, 7-18 months and ＞18 months), 2,216 serum samples were collected from 38 cattle herds in 12 leagues and cities in Inner Mongolia of China. Positive rates of Bovine Viral Diarrhoea Virus (BVDV), Bovine Rotavirus (BRV), Bovine Coronavirus (BCoV), Escherichia coli K99 (E.coli K99), and M. paratuberculosis (Mptb) antibodies were detected in the samples by ELISA to determine the epidemic trends and differences of the five pathogens in Inner Mongolia. The positive rate of BVDV vaccine higher than 90% in each age category of cattle, and the prevalence rates of BRV and Mptb in other ages significantly higher than ＞18 months (P <0.05). Except BVDV, the prevalence of BCoV was the highest in 0-2 months old (74.88%), the highest positive rate in ＞18 months old is BRV (63.31%), the infection of viral pathogens were serious in Inner Mongolia. With the highest mixed infection (33.74%) being BRV and BCoV in the category of 0-2 months, and there was a mixed infection of BRV and BCoV at four age stages, Only double and triple infections were detected in cattle aged 2-6 months and 6-18 months, quadruple infections were detected in cattle aged 0-2 months and ＞18 months. Furthermore, obvious regional epidemiological differences among the five pathogens were observed, 5 pathogens were detected in 11 regions, Hulun Buir city was seriously infected with bacterial pathogens, only antibodies to viral pathogens were detected in Ulanqab city. All the above detected pathogens can trigger high mortality and poor prognosis in cattle. This study is the first to report the prevalence and characteristics of the main pathogens of bovine diarrhea in large-scale cattle farms in Inner Mongolia, China, which has practical significance for the future prevention and control of bovine diarrhea and reduce economic losses in cattle farming.