RESUMO
An adult dairy cow fatally affected with winter dysentery was investigated pathologically and virologically. The cow had severe anemia and diarrhea with massive blood. Pathologically, the loss of surface epithelial cells and necrosis of crypt epithelial cells in the large intestine were observed. Bovine coronavirus (BCV) antigen was observed in necrotic crypt epithelial cells of the large intestine. Virus particles were found in the necrotic epithelial cells of the large intestine. Virologically, BCV was isolated from the feces of the dead cow. The dead cow had no serum antibody against BCV although the co-habitants did. These suggest that severe infection of BCV in the cow without the BCV antibody accompanied by severe hemorrhagic anemia resulted in the cow's death.
Assuntos
Anemia/veterinária , Doenças dos Bovinos/virologia , Infecções por Coronavirus/veterinária , Coronavirus Bovino/crescimento & desenvolvimento , Disenteria/veterinária , Anemia/sangue , Anemia/patologia , Anemia/virologia , Animais , Anticorpos Antivirais/sangue , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/patologia , Infecções por Coronavirus/virologia , Disenteria/sangue , Disenteria/patologia , Disenteria/virologia , Evolução Fatal , Fezes/virologia , FemininoRESUMO
Phylogenetic tree and partial nucleotide sequence analysis of RNA segment 3 were conducted to compare the Ibaraki virus (IBAV) strains from three epidemics in Japan, and serotype 2 epizootic hemorrhagic disease virus strains isolated in Australia, Taiwan, and Canada. Each strain was classified relative to the Ibaraki disease (IBAD) epidemics, which occurred in 1959-1960, 1987, or 1997-1998. In particular, major variation of the gene was identified in the strains isolated after 1997 when a new type of IBAD with the abnormal birth was confirmed. Ibaraki viruses isolated in Japan were more closely related to Taiwanese and Australian strains based on genetics, while the Canadian strain was more distantly related.
