DETECTION AND GENOMIC ANALYSIS OF CANINE PARVOVIRUS BY THE POLYMERASECHAIN-REACTION

Prevalence of canine parvovirus type 2 (CPV-2) in Japanese dogs and ge nomic variations among the virus strains were examined. Two-step polym erase chain reaction with double-nested primer pairs designed in the N S and VP1/VP2 genes of CPV-2 was developed for the detection of the vi ral genome in faecal samples. A total of 74 samples obtained from diar rhoeal house dogs between 1993 and 1995 were tested by the PCR. The vi rus-positive rate was 54.1%, showing that CPV-2 is still involved in m any cases of acute infectious diarrhoea in Japanese dogs. The VP1/VP2 gene of the positive samples was subjected to restriction fragment len gth polymorphism (RFLP) analysis and nucleotide sequencing. RFLP patte rns of the samples were almost identical to those of one CPV-2 strain (TDKet-91-42) isolated in 1991, but different from those of the CPV-2 in the late 1970s and 1980s. The results suggest that a new genotype o f CPV-2 appeared and spread among Japanese dogs in the early 1990s.