Abstract: According to the canine parvovirus(CPV) VP2 gene sequences in GenBank,two pairs of primers 1F/1R and 2F/2R were designed and synthesized. Taking the DNA extracted from the feces samples of dogs suspected to be infected with CPV as templates,two fragments covering VP2 gene with the length of 1325 and 758 bp were amplified respectively,after cloning and sequencing of the two fragments,eleven complete VP2 gene sequences with the length of 1755 bp were obtained through splicing. The analysis of nucleotide homology showed that compared with 21 reference strains of CPV at home and abroad in GenBank,the nucleotide homologies of these eleven VP2 gene sequences were from 96.2% to 99.8%. By using the DNAStar software,the B cell epitopes of VP2 protein were predicted to be in the sections of Met1-Val38,Met73-Val82,Met96-Ala103,Lys151-Thr170,Gly235-Phe243,Leu294-Phe303,Ala359-Thr399,IIe469-His483,Ala503-Arg520 and Lys570-Tyr584. Compared with the amino acid sequences of the reference CPV strains,the amino acid residues at the sites of 426 and 555 of the VP2 protein coding by these eleven VP2 genes were Asp and Val respectively,which indicated that the genotypes of these eleven CPV were all CPV type 2a and also primarily proved that the CPV-2a was the main prevalent strain in Chengdu area.

Key words: canine parvovirus (CPV); VP2 gene; clone; genotype