Primary isolation of cytopathic bovine rotaviruses on fetal rhesus monkey kidney cells

Primary isolation of bovine rotaviruses was successfully performed on rolling cultures of MA104 cells following trypsin treatment of fecal samples and cells. Fifty-one fecal samples were obtained from 22 herds affected with naturally-occurring acute diarrhea in calves during a period of over two years. Rotavirus particles were demonstrated in only 10 fecal samples by electron microscopy. Fourteen cytopathic bovine rotaviruses were isolated from positive samples and could be serially cultivated on MA104 cells. The presence of virus was identified by specific immunofluorescence in infected cells. These data indicated that approximately 30% of the herds affected with acute diarrhea in their calves were associated with rotavirus infection.