The Serological Detection And Electron Microcopic Observation Of Foot And Mouth Disease Virus

The IgG was purified from porcine anti-FMDV serum by ammonium persulfate and Sephadex G-25,and the FITC was labeled on the IgG so that the fluorescent antibody was prepared.This fluorescent antibody was used to detect the antigen of the FMDV in BHK-21 cells,the results suggested that this method could detect the viral antigen of FMDV in BHK-21 cells. The optimal concentration of fluorescent antibody was determined as 1:40 .The fluorescence could be specifically inhibited by anti-FMDV positive serum.The fluorescent antibody was applied to detect BHK-21 cells slides and smears infected with CS and LB strains . The results showed that all of the infected slides were positive ,but the blank contrast of cell slides were negative.The sheep red blood cells were sensitized by purified IgGThe positive antigen of FMDV was detected by reverse indirect haemagglutination test(RIHA) ,the results indicated that the titer accounted for 1:960.The samples in the field were detected by this method ,the positve rates were as fallows: 80%(8/10)for vesicular skin, 94.7%(18/19) for BHK-21 cells infected with FMDV and 78%(14/18)for infected culture of infected neonatal rats.The FMDV was propogated in BHK-21 cells,and preliminarily purified by sucrose reverse osmosis and Sephadex G-200 chromatography. The purified FMDV was used to sensitize sheep red blood cells , agglutination could took place between the sensitized cells and FMD positive serum,which cold be inhibited by the positive antigen of FMDV. And the indirect hemagglutination test (IHA)was applied to detect samples of serum in the field. The results showed that the positive rate of bovine serum samples was 100%(17/17),and the positive rate of swine serum samples was also 100%(20/20). With sucrose gradient centrifugation,the FMDV become more purified. The purified FMDV was observed under tansmission electron microscope,the results is that the virions without envelope characterized by heavely stained center, average structure,obvious and smooth fringe,and its diameter was 20...