The 2016 Symposium of Animal Vaccine Development Center

Dose determination of inactivated Actinobacillus pleuropneumoniae vaccine

JC Hung, ML Wu, YT Hung, CS Chang, JP Wang, JH Lin, ZW Chen, MW Hsieh

In this study, 6 serial antigen concentrations of Actinobacillus pleuropneumoniae (APP) were prepared as bacterins to choose the optimal antigen concentration as APP vaccine. In the mice experiments, using serotype 2 APP field strain to challenge the immunized ICR mice, the protective titers were 10.0, 10.0, 7.5, 4.6, 6.6 and 2.2, respectively. The protective titers showed dose-dependent effect with antigen concentrations. In the pig experiments, using 10^3 CFU of serotype 2 APP field strain to challenge the immunized pigs, although the typical signs of APP infection were observed in the immunized pigs, all pigs survived and showed better antibody titers and lowered pathological lung scores after necropsy compared to control pigs. The efficacy of APP bacterin with optimal antigen concentration was confirmed by the challenge test.