parvoviruses isolated from the intestines of dogs that died of an enteric infection were propagated in various parasynchronized canine and feline cell cultures. Viral antigen could be visualized in infected cell cultures with the aid of fluorescein-labeled feline, as well as porcine, parvovirus antisera, and in an indirect test with sera from dogs that had recovered from a parvovirus infection. The virus hemagglutinated porcine RBC at 4 C and 25 C but not at 37 C. An inactivated canine parvovirus vaccine elicited an immune response, but no adverse reactions, when inoculated into dogs. Vaccinated dogs were immune and did not show any clinical signs when challenge exposed with virulent virus, whereas nonvaccinated, nonimmune dogs became clinically ill when inoculated with the same virus. Humoral hemagglutination-inhibiting parvovirus antibody values corresponded well with susceptibility and resistance to experimental inoculation of dogs with canine parvoviruses.