Imunogenicity Comparison Of Riemerella Anatipestifer Inactivated Vaccine In Oil Adjuvan With Bi-combined Vaccine In Different Adjuvans

Riemerella anatipestifer(RA) inactivated vaccine in oil adjuvant was made with serotypes 1 isolated strain, Riemerella anatipestifer-Escherichia Coli inactivated bi-combined vaccine in oil adjuvant and Riemerella anatipestifer-Escherichia Coli inactivated bi-combined vaccine in propolis adjuvant were made with RA serotypes 1 and E.coli serotypes O78 isolated strains. These three vaccines are studied in this paper, and the results are as follows:1. Safety inspection:Vaccines were inoculated subcutaneously to 3-days old ducklings with 4 doses of 0.5ml, 1ml,2ml and 3ml after sterility test. When inoculated with RA oil vaccine and RA-E.coli oil vaccine, few of the ducklings felt a bit off color and there were inflammatory tubers on the injection sites. But the ducklings recovered soon after 5 to 8 hours. At the same time, the other two groups were both healthy. Therefore, the vaccines are all safe to ducklings.2. Optimization dose:Vaccines were inoculated subcutaneously to 3-days old ducklings with 4 doses of 0.25ml,0.50ml,1.00ml and 2.00ml after sterility test. Ducklings were challenged subcutaneously in the neck 10 days after immunized. The RA challenge contained approximately 109CFU in 1ml, and the E.coli challenge contained approximately 2.00×108CFU in lml. Ducklings got better protection when immunized with 0.25ml vaccines and got 100% protection when immunized with 0.50ml vaccines. Therefore, the optimization dose is 0.50ml.3. Immunizing potency:Vaccines were inoculated suhcutaneously to 8-day old ducklings with a dose of 0.5ml after sterility test and safety inspection. Ducklings were challenged subcutaneously in the neck in 7,14 and 21 days after immunized.. The RA challenge contained approximately 5.20×109CFU in 1ml, and the E.coli challenge contained approximately 1.00×109CFU in 1ml. Homologous challenge with RA demonstrated that immunoprotective rates were 50%,80% and 100% respectively when 7,14,21 days post vaccinated with RA inactivated vaccine in oil adjuvant, immunoprotective rates were 50%,70% and 100% respectively when 7,14,21 days post vaccinated with RA-E.Coli inactivated bi-combined vaccine in oil adjuvant, immunoprotective rates were 60%,80% and 100% respectively when 7,14,21 days post vaccinated with RA-E.Coli inactivated bi-combined vaccine in propolis adjuvant. Homologous challenge with E.Coli demonstrated that immunoprotective rates were 60 %,80% and 100% respectively when 7,14,21 days post vaccinated with RA-E.Coli inactivated bi-combined vaccine in oil adjuvant, immunoprotective rates were 70%,100% and 100% respectively when 7,14,21 days post vaccinated with RA-E.Coli inactivated bi-combined vaccine in propolis adjuvant. RA-E. Coli inactivated bi-combined vaccine in propolis adjuvant is fit for commercial ducklings because of it generated antibody quickly and its highly protective rate.4. Antibody level:Vaccines were inoculated suhcutaneously to 8-day old ducklings with a dose of 0.5ml after sterility test and safety inspection. Antibody levels were tested in 7,14 and 21 days after immunized. Tube agglutination test showed that the specific antibody peaked 21 days post vaccinated with RA-E.Coli inactivated bi-combined vaccine in propolis adjuvant, the specific antibody peaked 35 days post vaccinated with RA-E.Coli inactivated bi-combined vaccine in oil adjuvant and could still be detected 91 days post vaccination. RA inactivated vaccine in oil adjuvant and RA-E.Coli inactivated bi-combined vaccine in oil adjuvant are fit for breeding ducklings because the antibody levels were higher than RA-E.coli inactivated bi-combined vaccine in propolis adjuvant after the peak antibody level. All the 3 vaccines could maintain high level of antibody especially after immunized and the RA-E.coli inactivated bi-combined vaccine in propolis adjuvant is the best.