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A Serologic Investigation for Coronavirus and Breda Virus Antibody in Winter Dysentery of Dairy Cattle in the Northeastern United States

1992; SAGE Publishing; Volume: 4; Issue: 4 Linguagem: Inglês

10.1177/104063879200400415

1943-4936

Herbert J. Van Kruiningen, V. P. Castellano, Marion Koopmans, Louis Harris,

Animal Disease Management and Epidemiology

Since 1980, the amount of evidence implicating a bovine coronavirus as the cause of winter dysentery has been increasing. Japanese workers were the first to recover a coronavirus from the feces of a cow with “epizootic diarrhea”; this discovery was followed by similar reports from Belgium and the United States. 1 Because coronavirus-like particles and coronavirus antigen can be found in the feces of a high proportion of normal dairy cows in some herds during the winter stabling season, the significance of these isolations has been interpreted with some reservation. Serologic studies revealed hemagglutination-inhibition seroconversion to reference strains of bovine coronavirus in 59% of affected Japanese cattle; 15 workers from Ohio reported 4-fold or greater rises in serum neutralization (SN) titers in 19 of 26 animals (73%); and the British, using a latex agglutination inhibition test, found seroconversion in 3 of 5 affected cattle? We recently reported 63% seroconversion by an enzyme-linked immunosorbent assay (ELISA) method, in 35 sick animals from 8 herds with winter dysentery. Additional evidence, and perhaps the most convincing, that a coronavirus is responsible for winter dysentery, is the demonstration by immunoperoxidase and electron microscopy methods of coronavirus in damaged colonic epithelial cells and mucosal macrophages of both spontaneous and experimentally induced cases. 18 In the Netherlands, however, there has been a serologic association of Breda virus infection with the occurrence of winter dysentery. Sera from 149 cows from 19 farms were tested by a blocking ELISA method, and 4-fold or greater seroconversion was found in 7-60% of cattle tested from 10 of the farms; cattle from 9 farms showed no seroconversion. In view of questions raised about the respective roles of Breda virus and coronavirus, previously assembled and some newly acquired sera were tested (retested in the case of previously assembled sera) for the presence of antibodies to these 2 viruses. The procedure used to obtain and select the sera used in this study was described in the prior report. Two serotypes of Breda virus are recognized; Breda virus serotype 1 (BRVl) represents the original isolate from Breda, Iowa, and serotype 2 (BRV2) comprises an isolate from Ohio and the second Iowa isolate. Thus far, Breda virus has not been successfully propagated in tissue culture; therefore all studies conducted with this agent employ density-gradientpurified virus particles obtained from an experimentally in-