| According to the published gene sequence of porcine circovirus (PCV) from Genbank, a pair of primer specific to porcine circovirus type 2(PCV2) were designed and synthesized. Lymph nodes and spleen of a swine suspected PMWS broke out in some porcine farm in Jilin province were detected by polymerase chain reaction (PCR). The result showed that 2 PCV2 positive samples were detected in 9 samples. The average positive rate is 22.2%. It approved that PMWS existed Jilin province. The PCV2 positive samples were abraded, sedimented by centrifugation, filtered and inoculated to the PK-15 cell line, which were not contaminated by PCV1. The extract viral DNA in PK-15 cells after 6 passages was detected with a pair of primers of PCV2 and obtained positive result. The result showed that the PK-15 cells free of PCV were infected by PCV2. Then the viral samples were pured and observed with electronic microscope. They were 17nm in diameter. In the cytoplasm, the specific fluorescence particles were observed in the frozen section strained by indirect immunofluorescence test specific to PCV2. According to above results, the isolated strain belongs to PVC2 and named PCV2 JL 01 and 02 strain.According to the published ORF2 gene sequence of PCV2, a pair of primer were designed synthesized and ORF2 gene was amplified by PCR. The product was about 0.7 kb in size detected by agarose gel electrophoresis. It was accord with the anticipated fragment. The products were purified and sequenced. The result showed that the ORF2 genes of JL01 and JL02 isolated strains are 702bp in size and they shared 99.9% homology with the referential strains and 91.9-99.4% homology with other isolated strains.That the viruses were isolated, identified and sequence analysis of ORF2 gene will supply good foundation for aetiology, diagnosis and control of PCV2. And the result also gives some help on researching the bioactivity of ORF2 protein-code and establishing the diagnostic kit.
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