SummaryInfection of calves by rotavirus could lead to diarrhea or subclinical disease. Therein, kinetic of viral excretion from a group of asymptomatic calves, previously exposed to a virulent strain of rotavirus, is compared to that of a group the calves of which had diarrhea associated with rotavirus infection. As determined by an enzyme‐linked immunosorbent assay (ELISA), duration of rotavirus shedding in feces and maximum yield of virus antigen were similar within the two groups of calves. Rotaviruses isolated from the two above groups of animals were antigenically related as shown by neutralization tests, and showed a similar RNA electrophoretic profile. In conclusion, it is likely that both asymptomatic and diarrheic calves infected by rotavirus are equally a major source of contamination to contact healthy calve