Epidemiology Investigation And Establishment Of Diagnostic Method Of Classical Swine Fever

Classical Swine Fever(CSF) is a highly contagious and hemorrhagic disease of Suidae,which is caused by Classical Swine Fever Virus(CSFV),a member of the genus Pestivirus of family Flabibiridae.Although the implementation of statuory vaccination program is effective in control of the disease without major outhreaks,the CSF is still sporadic in China,causing a complicated situation with a huge economic lost every year.The effieiente control or eradication of the CSF depends on the better understanding of overall epidemiological status.In this study,we firstly investigate the epidemiology of pig farm doubted infecting swine fever,exound epidemic status from infected condition and clinical situation to pathological change and find integrate control measure on this foundation.Then,adopt the infected tissue to carry out separate and identification by molecular biology method on genic level.First,observe the separated virus by electron microscope,find the round shape of virus are similar to Classical Swine Fever Virus has envelope and nuclear is he hexagon.Then made the virus in PK-15 cells, observed CPE,extracted RNA of virus to RT-PCR meanwhile,and amplificated the E2 gene linked to PMD -18T vector.The result of sequencing demonstrate the nucleotide homology between the separated strain and the standard strain of virus is 82.5%-94.4%,amino acid homology is 89.3%-94.0%.In order to diagnose the CSFV high effectively,the experiment designed a pair of primer to aim directly at E2 gene,then established PCR diagnose method of CSFV.The method of research was demonstrated has well specificness,sensitiveness and reproducibility.Furthermore detected the suspected infected tissue of CSFV and lymph node and tonsil of healthy pig by above method,rate of detection was 62.9%and 11.8%respectively.