In blood sera of rabbits, guinea-pigs, laboratory rats and white mice, specific antibodies were detected after vaccination and revaccination with an inactivated vaccine against porcine parvovirosis using the haemagglutination inhibition test. The strongest immune response was found in laboratory rats showing haemagglutionation inhibiting antibody titres in the range of 256-2048; guinea-pigs also showed aubstantial titres in the range of 16--1024. Lriwer immune respcinses were detected with white mice (titres 16-32) and rabbits (titres 8-128). These results indicate that the most suitable laboratory animals for efficacy testing of inactivated vaccines against porcine parvovirosis are· laboratory rats and guinea-pigs.