The Probing Of A Potential Method Distinguishing The Attenuated Hog Cholera Virus Lapinized From The Wild Type Virus Of HCV

In this study Reverse Transcriptase Polymerase chain Reaction (RT-PCR) was applied to detect hog cholera virus in the tonsils of the healthy pigs and in the abortions and the dead born. A pair of primers, A1/A2 which can amplify nucleic acids of all HCV strains, has been applied. The result showed that 11 of 70 tonsils of healthy pigs from different places in Guangxi such as Baise, Xijiang and Liuzhou etc. and the positive rates were 15.7%, and that 9 of 52 the abortions and the dead born were positive and positive rates were 17.3%. The results demonstrated that healthy virus carriers exist in Guangxi, which was2very serious, and that HCV is one of the causes resulting in breeding disorders.On the basis of the above experiments, two pairs of primers, EP1 /EP4 and EP2/EP3 (named temporally non-universal primers) were designed according to the moderate conserved E2 gene to amplify the nucleic acids of HCV in the above positive samples and the positive samples of the sick pigs, HCLV and Shimen strain. 19 positive samples, of which there were 10 samples of sick pigs, were tried, but no one has specific nucleic acid band, while HCLV and Shimen strain have. Then Restrictive Fragment Length Polymorphism (RFLP) was applied to analysis the PCR product, which was synthesized from nonstructural gene P120 of HCV, of the 19 positive samples, HCLV and Shimen strain. We found HCLV, Shimen strain and Guangxi field wild virus all have one recognition sequence of Rsa I in the non-structural P120 gene of HCV. But HCLV has different locus of recognition sequence from other strains. The research demonstrated that HCLV could be distinguished from the field wild virus with primers A1/A2EP2/EP3 and EP1/EP4 and by RFLP technique and that the non-universal primers was more convenient and feasible, which would play an important role in preventing and putting down Hog Cholera.(HC).