[Immunobiologic properties of swine rotavirus].

Immunobiological properties of swine rotaviruses were studied. A field isolate of this virus was markedly virulent for newborn colostrum-less piglets. An attenuated strain of swine rotavirus was obtained by serial passages in continuous cell cultures (MA-104 and SPEV). The virus of the 60th passage was nonvirulent for colostrum-less piglets although produced marked seroconversion. Naso-oral immunization of piglets with the attenuated strain prevented the manifestation of clinical disease upon challenge with the virulent swine rotavirus. Besides, the swine rotavirus of the 60th passage showed cross-protective activity against virulent human rotavirus in modelling human rotavirus infection in colostrum-less piglets.