Research On The Cross-immune Of Different Serotypes Strains Of Infectious Bronchitis Virus

Infectious Bronchitis(IB) is an acute infectious respiratory disease,caused by the avian infectious bronchitis virus(IBV) Since broke out in USA in the 1931s,Disease pathogen is coronavirus Branch, chicken coronavirus infectious bronchitis virus IB have become an important disease of poultry around the world. The serotype of IBV has more than 30 categories, such as M41,Conn,Iowa97,Gray,Holte,JMK,Clark333,SE17,Florida,Ark99 and Australian T widely exist. Different serotypes have lower or no protection. Currently,IB has often been found in China widely.,even if in the farm where had vaccinate IB vaccine, Which result in serious economic losses to the poultry Industry.There is a serious outbreak of avian infectious bronchitis disease in Henan province recently. In order to identify the exact causes,So it is important to choose suitable vaccine or new IBV strain which was isolated in local area in order to control outbreak of IB.The HI test and Virus neutralization (VN) revealed that the serotype of CH07 strain and RW08 strain were different of M41 strain and Conn strain. The results show, Conn strain, CH07 strain, RW08 strain and strain M41 HI titer difference greater than 2 times, CH07, RW08 strain and Conn strains of HI titers are greater than 2-fold difference, according to different strains of the same anti- HI serum titer 1 to 2 times the difference when the same type of determination of serum standards However, the serotypes of CH07 strain and RW08 strain were identical. Virus neutralization test using different strains were serotype, test results show that, IBV isolates CH07 strain, RW08 strain and a common standard strains in the antigenicity of the existence of significant differences So CH07 strain and RW08 strain isolated in Henan are new serotype. Moreover, it is epidemic in Henan province.Use of IBV RW08 strain and M41 strains were inactivated preparation, and preparation of the two strains inactivated bivalent were chicken immune trial. M41 strains were used, CH07, and RW08 attack such as toxic strains cross protection test, the second price of oil emulsion immunohistochemistry serotype M41 strain not only on the protective effects of attacks, while serotype strains resistant to RW08 attack. Antibody test showed that, IB divalent oil emulsion immune group and the RW08 strain, M41 strains of Immune oil emulsion alone group, antibody levels fairly. IB bivalent oil emulsion can not only stimulate the body to generate immune to a comparable level with the antibody alone.