Construction Of Pseudorabies Virus SH Strain PK～-Deleted Mutant And PK～-gG～-Double Deleted Mutant And Primarily Study Their Immumogenicity

Pseudorabies(Aujeszky'disease) is caused by Pseudorabies virus(PRV) or suid herpesvirus l, a member of the family of Herpesviridae subfamily AIphaherpesvirinae. Pseudorabies is an acute infectious disease and characterized by high fever, extreme itching(not in swine)and encephalomyelitis in pigs, bovine, sheep and wild animals. Except pigs, PRV infection could cause death infection, almost infectious animal invariably die. Pigs is the natural host of PrV, also its main storing host and main infectious origination. Infection may run an acute or subclinical course, depending on the virulence of the virus and the age of the pig. In unvaccined populations, abortions and stillbirth in pregnant sows, neurological disorders in piglets, and respiratory signs in fattening pigs are the most prominent disease symptoms. Mortality in young piglets approaches 100%, whereas mortality in fattening pigs is usually less than 5%. Infected pigs shed virus for 2-3 weeks, and the virus may remain in a latent state. Reactivation of latent PRV may result in excretion of infectious virus and transmission to other pigs .Thus, pigs that once had undergone an PRV infection are potential sources of virus for their entire lifetime . Immuned by PRV inactivated and attenuated vaccines could in some extent prevent Pig from the clinical infection of Pseudorabies, but is not so effective as to both completely inhibit PRV replication at the Primary replication site and excretion of infectious virus and transmission to other pigs. Pseudorabies had caused significant economic losses in the pig industry around world, so far about 46 country and region had reported the disease .Vaccination is a effective measure to prevent Pseudorabies. classical vaccine such as inactivated and attenuated vaccines could prevent Pig from the clinical infection of Pseudorabies, but cannot completely inhibit PRV replication and excretion of infectious virus and transmission to other pigs. with the development of molecular biological techniques, several gene deleted PRV vaccines were produced and played an important role in prevention and eradication of this disease. gene deleted PRV vaccines delete one or several virulent determinant gene, so can decrease virus virulence ,prevent attenuated virus...