YN Strains Of Duck Hepatitis Virus Isolation And Identification And Reconstruction Of The Recombinant Duck Plague Virus Which Expressed The VP1 Gene Of YN Strain

Duck hepatitis, also called duck viral hepatitis, is caused by duck hepatitis virus. Duck hepatitis outbreak in 1949 in Long Island and it occures around the world. Pathogen, which caused duck hepatitis, are typeâ… ,typeâ…¡,typeâ…¢duck hepatitis virus. But at the same time,there is a new type duck hepatitis which is different from the three types above in the production. Among the three types,the type III duck hepatitis is common. A lot of experiments show that main antigen of the typeâ… DPV is protein VP1,and there is a high conservation.Recombinant live vector vaccines as a third-generation vaccine has been very mature, especially herpesvirus. Duck plague virus is a herpesvirus. Plague, also known as duck virus enteritis, caused by duck plague virus, but also is one of the major diseases causing huge losses to the duck industry, the traditional attenuated duck plague vaccine can play a very good immune protection.In this study, a strain of duck hepatitis virus was isolated, and analysised the sequence, and compared the homology with I-DHV standard strain, the results indicate that the isolation is the I-DHV. The protective antigen,duck plague virus VP1 gene fragment,was obtained by the molecular biology.The transfer vector was constructed with CMV as a promoter, LacZ as reporter gene,the vector transfected with the DPV for homologous recombinating, the recombinant DPV live vector vaccine which express the protective antigen VP1 gene of typeâ… DHV was constructed with C-KCE duck plague attenuated vaccine as an virus vector.The antibody detection experiments indicate that recombinant duck plague virus proliferates in vaccinated animals.During the Statistics,the antibody level of duck plague was the highest,reached 6.72, but the antibody of-duck hepatitis virus was not detected. At the same time, anti-duck plague virus antibody levels in the test group which innoculated with recombinant virus was lower than it in the positive control group which innoculated with a simple vaccination of duck plague virus.In this study in first time, duck hepatitis virus protective antigen constructed with duck plague virus vector and the recombinant virus may play a role in the governance of two seedlings. Conventional attenuated vaccine has some of the inevitable shortcomings,for example, the virulence became strong, the immune ducks in a stealth infection status is in immune suppression because of the vaccine have a certain virulence factors.In this experiment,the major virulence factor TK gene of duck plague virus,was knockouted and the virulence of duck plague virus greatly weakened, while the virus does not occur the phenomenon of atavistic and virulence back stronger.