Study on virus combined culture and combined immunity of inactivated ND IB Oiladjuvant bivalent vaccine

Lasota strain of Newcastle Disease virus (NDV) diluted at 100 times was mixed with different types of Infectious Bronchitis virus (IBV) respectively, in different dilution and coinjected into urinary vesicle of 10 days old chick embryo The allantoic fluid was collected after 96 hours,incubation The reciprocal effects of the virus were evaluated by hemagglutination test for NDV and counter immunoelectrophoresis for IBV THE results indicated that the hemagglutination titer of NDV reached 11㏒2 and the counter immunoelectrophoresis titer of IBV reached 9㏒2 when 100 times diluted NDV was cocultured with 1 000 times diluted IBV in chick embryo Then the NDV and IBV were inactivated by formalin and prepared for the inactivated ND IB oiladjuvant bivalent vaccine according to the normal way The chickens were vaccinated at 21dayage The titers of antibody to ND were 2、3 6、4 8、5 8、6 2、6 5、6 8、6 5 and the titers of antibody to IB were 2、3 3、4 6、5 9、6 2、6 4、6 6、6 4 on 0、7、14、21、28、35、42、49 days postvaccination respectively When the immunized chickens were challenged with virulent NDV and IBV, the protection rate was 100%. These results prove that the ND IB oiladjuvant bivalent vaccine could control ND and IB (008)