Isolation And Identification Of Edema Pathogen In Piglet And Immunological Control

16 strains of bacteria were isolated from sick or dead piglets. They were identified as Escherichia coli by its morphology, culture and biochemical characteristics. The pathogenic trail in mouse showed that 12 of the 16 strains were pathogenic bacteria. 12 strains were classified into 4 serotypes: O₂,O₈,O₁39,O₁41. The predominant O groups were O₁39 and O₈. strains of Different serotypes above pathogenic E.coli and O₁38,O₁39,O₁41 standard stub as vaccine strains which had widespread epidemical, strong pathogenicity and better antigenicity. The inactived vaccine was used to immune piglets and had better immunization. The evidence came from clinic investigation showed that the protect rate of the piglets edema disease reached to 99 percent.Blood samples were randomly collected from the swine before and after vaccined at a certain interval and serum were isolated. The result of determining antibody was that the rate of positive reaction of antibody in piglets can reach to 100 percent at 7 days after immunity. The antibody level reached to top 14 day after immunity. The effective antibody can lasted for 6 weeks. The results showed that serum antibody titer has the positive interraction with the clinic protection rates.