The immunoprophylaxis of of rotavirus infections in lambs.

The effect of colostrum or serum feeding on subsequent rotavirus infections was investigated in neonatal gnotobiotic lambs. Immunity after feeding colostrum did not depend on absorption of passively acquired antibody into the circulation. Protection against clinical disease depended on the volume of colostrum ingested. The protection afforded by feeding serum was specific, since serum free of rotavirus antibody failed to confer protection. Immune serum fed at a rate of 2.5 ml per kg twice daily protected against rotavirus infection. Also, it was shown by intraperitoneal inoculation of immune serum that protection could occur in the absence of ingested antibody, presumably by transfer of antibody into the gut. The implications of these findings for immunoprophylaxis of rotavirus diarrhoea in lambs and calves are discussed.