Negative contrast electron microscopic diagnosis of viruses of neonatal calf diarrhea.
Ninety-one cases of neonatal calf diarrhea were examined for viruses with negative contrast electron microscopy. Viruses were demonstrated in 41% of the cases. Reo-like viruses and corona-like viruses, and mixed virus populations were observed in 12%, 20% and 9%, respectively. Twenty-six of the cases were examined by negative contrast electron microscopy, and by virus isolation or by fluorescent antibody technique. There was an 81% agreement in obtained results. The disagreements resulted from the demonstration of a viral agent by negative contrast electron microscopy while the other techniques did not indicate a virus. The results suggest that negative contrast electron microscopy is a more sensitive diagnostic tool for demonstration of viruses associated with neonatal calf diarrhea than are viral isolation or the fluorescent antibody technique.
D000818:Animals; D000831:Animals, Newborn; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology*; D003332:Coronaviridae / Q000302:isolation & purification / Q000648:ultrastructure; D003967:Diarrhea / Q000382:microbiology / Q000662:veterinary*; D001908:Diarrhea Viruses, Bovine Viral / Q000302:isolation & purification; D005243:Feces / Q000382:microbiology; D010849:Picornaviridae / Q000302:isolation & purification / Q000648:ultrastructure; D012328:RNA Viruses / Q000648:ultrastructure*; D012087:Reoviridae / Q000302:isolation & purification / Q000648:ultrastructure