Serosurvey Of Four Bovine Viral Disease In Shanghai Dairy Herds And Expression,Purification Of Recombinant Bovine Interferon α,γ

In the recent years,with the rapid development of Chinese dairy and continuous improvement of largescale and intensive level,the situation of infectious bovine viral disease prevention and control is more and more severe.Foot-and-mouth disease,bovine viral diarrhea-mucosal disease,infectious bovine rhinotrache,bovine coronavirus and bovine rotavirus have great effect in Chinese dairy。Shanghai,as the cardle of Chinese dairy,paied great attention on the animal disease prevention and control system.Interferon(IFN),which is generated by cells inducted by inducer,is a group of glycoprotein that has antiviral activity and immunoregulation function.IFN can be divided into three types:Ⅰ,Ⅱ,Ⅲ.IFN type I has the strongest antiviral activity,and IFN type Ⅱ has crtitical roles in the modulation of immune reponses.HuIFN and PoIFN have been used in clinic for many years,however BoIFN hasn’t been used in dairy.This study was mainly about the serosurvey of bovine viral disease in Shanghai dairy herds,which provided evidence for the prevention of viral disease in dairy.Also,we expressed and purificated of recombinant bovine interferon-α,γ.1 The serosurvey of four bovine viral disease in Shanghai dairy herds The study was about the prevalence of BVD,IBR,BCV and BRV infection in Shanghai dairy herds.ELISA kits were used for detection detected in serum.Serum samples(n=920)collected from 19 dairy herds were examined BVDV antigen and IBRV antibody;Serum samples(n=200)collected from 9 dairy herds were examined BCV and BRV antibody.To contrast the differences among the dairy herds including management,multiplication and disease.The study shows that the percent of IBR,BCV and BRV antibody-positive were 46.74%,97.00%,97.50%.The percent of BVD antigen-positive was 3.70%.2 Expression of recombinant Bovine interferon-α,γ To improve the expression of soluble recombinant bovine interferon-α,γin Escherichia coli,the synthetic genes coding for bovine interferon-a,y mature protein were inserted into vector pCold II and expressed in E.coli BL21(DE3).The optimization of the recombinant protein expression conditions showed that the maximum of bovine interferon-α,γ were obtained under the condition of 0.64 and 0.32mm/L IPTG,9 and 12 h induction at 15℃,After affinity column purification,the purity of the recombinant protein were up to 99.2%,91.1%and the concentration was up to 36 mg/L,32 mg/L.The activity of the recombinant protein was about 1.0×10~6U/mg and 1.6×10~5U/mg in the MDBK/VSV system test.