ROTAVIRUS SHEDDING IN FECES OF GNOTOBIOTIC CALVES ORALLY INOCULATED WITH A COMMERCIAL ROTAVIRUS-CORONAVIRUS VACCINE

The purpose of this study was to monitor by negative stain electron mi croscopy the shedding of rotavirus in the feces of gnotobiotic calves orally inoculated with a commercial modified live bovine rotavirus-bov ine coronavirus vaccine. Negative stain electron microscopic examinati on detected vaccine rotavirus in only 1 of 41 daily fecal specimens co llected from 3 gnotobiotic calves during the 2 weeks following oral in oculation with a US Department of Agriculture-licensed modified live b ovine rotavirus-bovine coronavirus vaccine. In contrast, rotavirus was demonstrable by the same negative stain electron microscopic examinat ion procedure in 17 of 19 fecal specimens collected from diarrheic gno tobiotic or colostrum-deprived calves during the first 8 days after in oculation with virulent bovine rotavirus field strains. Rotavirus was also detected by this procedure in 4 enzyme-linked immunosorbent assay positive fecal specimens collected from naturally-infected diarrheic dairy calves. These results suggest that fecal shedding of vaccine rot avirus demonstrable by electron microscopic examination is uncommon fo llowing oral inoculation of calves with the bovine rotavirus-bovine co ronavirus vaccine.