Abstract: [Objective] To provide a scientific immunization program for the prevention and control of wild-type pseudorabies virus infection in a large-scale pig farm. [Method] Epidemiological investigation was carried out in the infected pigs that immunized with the classical strain of Bartha-K61, and the serum levels of gB and gE antibodies were detected by ELISA. [Result] The epidemiological investigation, pathological autopsy and serum antibody detection preliminarily confirmed that the affected pigs were infected by wild-type pseudorabies virus. Through the emergency immunization of vaccine prepared with pseudorabies virus HB2000 strain, adjustment of immunization procedures and implementation of drug health care measures, the mortality rate of finishing pigs was reduced from 2.56% to 0.60%; except for 4-week-old and 12-week-old pigs, the antibody levels against the wild-type pseudorabies virus of the other pigs were all decreased; the positive rate against the wild-type pseudorabies virus of the stud boars and 8-week-old, 10-week-old and 14-week-old pigs was 0. [Conclusion] The Bartha-K61 vaccine cannot provide the complete protection. It can effectively control the infection of wild-type pseudorabies virus by emergency immunization of vaccine prepared with HB2000 strain that sharing high homology with the prevalent viral strain. Furthermore, strengthening of the biological safety measures is also helpful and urgent.

Key words: wild-type pseudorabies virus, epidemiological investigation, ELISA, infection of wild-type viral strain, pigs