VP2Gene Sequence Analysis And Identification Of Isolated Canine Parvovirus From Beijing Changping District

In this paper, we have studied the mass immunization, the biological characteristics, popularfeatures, pathogenesis, detection technology, and the capsid protein VP2gene of the isolated canineparvovirus from Changping District of Beijing. The faeces and rectal swabs which were gathered from36dogs suspecting of caused by CPV were collected in Changping District of Beijing from January toMay of2010. By the colloidal gold test strip detection, hemagglutination assay, F81cells synchronizedculture, indirect immunofluorescence assay, PCR and other methods,10CPV strains were isolated andidentified successfully. The10CPV VP2genes were sequenced.1. CPV isolation and identification36samples of CPV were detected by the colloidal gold test kit and the hemagglutination test. Thepositive rates of CPV were69.4%(25/36) and41.7%(15/36). The result showed that thechromatography of colloidal gold test strip was more sensitive than the hemagglutination assay. It wasfurther tested by PCR and IFA to determine15samples of CPV, and10CPV strains were cultured inF81cell and isolated successfully.2. VP2gene sequence and analysisIt states that the nucleotide sequence and amino acids sequence of the measured sample strainswere high homology with the reference strains by comparition10positive samples VP2sequence withGeneBank accession through DNA Star sequence analysis software. Nucleotide homology was98.7%to99.9%, amino acid homology was97.4%to99.8%. The phylogenetic tree of the VP2gene sequenceanalysis showed that sample2~6,8~10VP2gene sequences in the CPV branch has the most similaraffinity with the BJ020-07which was isolated in Beijing of China. But it has the more distantrelationship with the other reference strains. The Sample7of VP2gene sequences in the CPV branchhas the most similar affinity with the56/00和CPV-193. They also belong to the same branch. TheSample1and CPV-vint (vaccine strain) has the most similar affinity with CPV-d, there were relativesfar relationship with other samples and reference strains.It demonstrates that CPV genetic variation of VP2in the Changping region is less since2010.Subtype analysis showed that the CPV main genotypes is also CPV-2a, accounting for80%（8/10）.CPV-2and CPV-2b are10%, respectively（1/10）.Strengthening for CPV research and identification in Changping District of Beijing CPV epidemicstrain not only are a practical and necessary to the healthy development of the modern Kennel industry,but also lay the foundation for the research and development of new type CPV vaccine.