The results of the intranasal vaccination of pups in the presence of maternally derived antibodies (MDA) to canine parvovirus (CPV) are reported. The minimal immunising dose of the modified live virus vaccine was evaluated in eighteen pups from three litters. Eight pups were vaccinated intranasally with 10(5.50) TCID50/ml of CPV vaccine. Another 8 pups were vaccinated with 10(4.50) TCID50/ml of CPV vaccine and the other 2 pups were vaccinated with 10(3.50) TCID50/ml of CPV vaccine. The vaccine intranasally administered was able to induce a good antibody response in pups with MDA even when the infectious titer per dose was lower than the one contained in parenterally administered vaccines.