Epidemic Characteristics Of Swine HE In Some Areas Of Heilongjiang Province And Pathogenetil Characteristics Of HE Infected Rats

An acute hepatitis caused by Hepatitis E(HE)infection caused by Hepatitis E virus(HEV)is mainly transmitted through the alimentary tract.Research findings in recent years,HE as a zoonosis,It plays an important role in the popularity and transmission of human pig and seriously threatens human health.In this study,blood biochemical methods were used to detect the level of liver function changes of ALT and AST in infected animal serum,and the changes of HEV IgG antibody in animal serum were detected by indirect ELISA method.RT-PCR method was used to determine whether the animals were infected with HEV.Histopathological examination was used to observe the damage of HEV infection to the liver of pigs and rats.Immunohistochemical staining was used to observe the localization of HEV ORF2 protein in pig and rat liver.give the result as follows:Harbin,Qigihar and Jiamusi,Heilongjiang,Heilongjiang,and Jiamusi City,there were symptoms of poor appetite,deep yellow urine,and light yellowing of visible mucous membrane in three different pig farms and scattered pig farms in different regions.Serum detection of ALT,AST and other liver functions showed that the two indexes of serum samples,ALT and AST in three cities were higher than those of the scale farms,but the difference between the positive rates of the three city farms and the retail households was not large.The positive rates of HEV IgG in the serum samples of the scattered household pigs were higher than those of the scale farms,but the difference between the positive rates of the three city farms and the retail households was not significant.2 month old the antibody serum samples of piglets were HEV IgG positive rate was higher than 6 month old of pigs.The samples of pig manure and pig serum in three regions and pig liver samples collected by slaughterhouse showed that all pig feces were not positive,and the positive rates of serum samples from scattered families were higher than those of scale farms,and the HEV ORF2 gene was detected in the pig liver samples in slaughterhouse.The liver tissue of pig liver of slaughterhouse showed inflammatory cell infiltration,fibrosis,vasodilatation and hyperemia,and vacuolar degeneration of liver cells in liver tissues of pigs infected with liver tissue.The positive signal of HEV ORF2 antigen was mainly distributed in the cytoplasm or nucleus of hepatocytes.In rats infected with HEV,the following symptoms usually appear in 3d~5d: loss of appetite,deep yellow urine and slight yellowing of visual mucosa.The levels of ALT and AST in the 7d infection group were significantly higher than those in the control group.The levels of serum ALT and AST in the 14 d infection group were significantly higher than those in the control group.The serum samples of HEV rats infected with HEV IgG showed that the serum HEV IgG antibody content in the 7d infected rats was significantly higher than that of the control group,and the serum HEV IgG antibody content in the 14 d infected rats was significantly higher than that in the control group.The HEV ORF2 gene was amplified in all the liver tissues of infected rats.The HEV ORF2 gene was amplified from some animal serum,but the amplification was more obvious than that of feces.The liver of infected rats showed histopathological changes,such as ocular cell infiltration,liver fibrosis,vasodilatation and congestion,and vacuolar degeneration of liver cells in different days of infection.The positive expression of HEV ORF2 antigen in infected rats was mainly distributed in cytoplasm and intestinal cytoplasm of hepatocytes.The results showed that there were HEV infection in different scale pig farms in Harbin,Qigihar and Jiamusi areas of Heilongjiang province,The presence of viral antigens and viral nucleic acids was detected by immunohistochemistry and PCR.The presence of toxic phenomena in different degrees of infected pigs.Rats infected with HEV can reproduce the disease characteristics similar to that of pigs infected with HEV.Rats can be used as HEV sensitive laboratory animals for the diagnosis of diseases.