Pathogenesis of canine parvovirus-2 in dogs: haematology, serology and virus recovery.

The pathogenesis of canine parvovirus-2 (CPV-2) was studied in orally inoculated conventional dogs using haematological, serological and virological techniques. Virus was first isolated from mesenteric lymph nodes on day 2 after exposure, tonsil on day 3 and small intestine on day 3. Viraemia occurred subsequently and was present in most dogs on days 4 and 5 after exposure. CPV-2 could be isolated from all tissues during viraemia. Relative pyrexia, lymphopenia and neutropenia occurred on days 5, 6 and 7 after exposure, respectively. Virus excretion in faeces began in most dogs on day 4 and continued despite the appearance of neutralising serum antibody. Specific serum antibody, detected in some dogs as early as day 3 and in all dogs by day 7 after exposure, eliminated viraemia and inhibited virus isolation from tissues in cell culture.