PREVALENCE OF SEROTYPES G6 AND G10 GROUP-A ROTAVIRUSES IN DAIRY CALVES IN QUEBEC

Fecal samples from diarrheic and nondiarrheic dairy calves (1 to 3 wee ks old) from 12 regions of Quebec, collected between 1992 and 1994, we re screened for group A bovine rotavirus (BRV) using a combination of 2 VP6-specific monoclonal antibodies (MAbs) in an enzyme-linked immuno sorbent assay (ELISA). The overall prevalence of BRV infection was 26. 4% (107/405). In diarrheic calves, BRV infection reached 74.3% (55/74) , but only 15.7% (52/331) in nondiarrheic calves. BRV-positive samples were serotyped by enzyme-linked immunosorbent assay (ELISA) using G6 and G10 specific MAbs. The analysis of 107 field samples revealed that , in diarrheic calves, 34.5% (19/55) were G6, 27.2% (15/55) were G10, 9% (5/55) were G6 and G10 positive, and 29.9% (16/55) were G6 and G10 negative. In nondiarrheic calves, 19.2% (10/52) were G6, 19.2% (10/52) were G10, 7.6% (4/52) were G6 and G10 positive, and 53.6% (28/52) wer e G6 and G10 negative. Rotavirus dsRNA was extracted from BRV-positive samples and examined by polyacrilamide gel electrophoresis (PAGE). Of 107 samples tested, 74 (69.1%) were positive, and all the samples dem onstrated a typical group A rotavirus migration pattern.