Sequential isolation of rotavirus from individual calves.
An outbreak of neonatal calf diarrhea was studied on a breeding farm of Japanese indigenous beef cattle. During the breeding season of 1982, 43 calves were born over the period 27 February-28 April. All but one of the calves suffered from neonatal diarrhea and 5 died. Bovine rotavirus was isolated in cell cultures from fecal specimens of 39 (90.7%) of the 43 calves during the outbreak, strongly suggesting that this was the causative agent; the virus was readily isolated from 81 (83.5%) of 97 specimens of diarrhea. Rotavirus was subsequently isolated from the feces of 7 of the calves in early May, more than one month after the initial virus isolation in early March. Two of these calves were again rotavirus-positive in early June, 41 days after the second virus isolation. Diarrhea had ceased in all 7 calves in March. Some antigenic differences were shown by the neutralization test between the early and later isolates from one of these calves, suggesting either re-infection with a serologically different virus, or persistent infection with the original virus following antigenic modulation.
D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology*; D002460:Cell Line; D003967:Diarrhea / Q000382:microbiology / Q000662:veterinary; D005243:Feces / Q000382:microbiology; D012401:Rotavirus / Q000302:isolation & purification*; D012400:Rotavirus Infections / Q000382:microbiology / Q000662:veterinary*
D000914:Antibodies, Viral