Isolation And Identification Of The Infectious Bovine Rhinotracheitis(IBR) Virus In Inner Mongolia

429 cow sera were collected from the dairy farms of six different areas of Inner Mongolia. The sera were tested for antibody to Infectious Bovine Rhinotracheitis virus (IBRV) by using enzyme-linked immunosorbent assay (ELISA) kit.The result indicated that there were infections of IBRV in these six areas. The highest infectious rate was 92% in cow , the lowest infectious rate was 2.78% and the average infectious rate was 46.62%.14 sceptical samples of IBR collected from Huhhot of Inner Mongolia were treated with the general method, then they were analysed by PCR. 4 of them were positive for IBRV. These 4 positive samples were cultured in Bovine Testicle cell, as a result, one of them caused CPE until it was passaged to the 7th generation.And as the passage times increased,CPE became more regular.Then TCID50 of the isolate cultured in Bovine Testicle cell, Aether and Chloroform-stability, neutralization test, PCR detection and other biological property identification of the virus were done. The result indicated: When the virus dose of innoculation was diversity, TCID50 was different. As it was 100μl per well, TCID50 was 10-6.75/100μl;as it was 20μl per well , TCID50 was10-3.375/20μl. The isolate was sensitive to Aether, Chloroform and Trypsin, sensitive to acid and base.The isolate had a positive reaction with a neutralization test,the titre of neutralizing antibody was 2-8.1. PCR detection also confirmed the isolate was IBRV. All these tests further proved the isolate was IBRV.