Detection of bovine coronaviruses from adult cows with epizootic diarrhea and their antigenic and biological diversities

Bovine coronavirus (BCV) was detected by reverse transcriptase-PCR, immune electron microscopy or virus:isolation from adult cows at 6 out of 6 outbre aks of epizootic diarrhea in Japan. Six BCVs isolated in feces, intestinal content or tracheal exudate of the cows were analyzed for their antigenic p roperties by cross virus neutralization (VN) tests. The isolates were divid ed into two groups, one of which had closely related antigenicity with the reference Mebus and Kakegawa strains of BCV, and another which showed signi ficant differences in VN antibody titers from the reference strains. Two is olates in the latter group, which were from the enteric and respiratory tra cts of the same cows, respectively, were distinguished from each other by E LISA using monoclonal antibodies against the Kakegawa strain. The isolates showed various hemagglutination and receptor destroying enzyme titers again st chicken or mouse erythrocytes.