Evaluation of an Experimental Vaccine for Atrophic Rhinitis in Piglets

Background: Commercial swine atrophic rhinitis (AR) vaccine contains killed Bordetella bronchiseptica and P. multocida toxin (PMT) from Toxigenic Pasteurella multocida. The recombinant PMT proteins used as vaccine candidates were seldom reported. Methods: In this study, we developed recombinant fragments of PMT to replace P. multocida toxin in AR vaccine to compare the efficacy of this vaccine candidate with the commercial vaccine. Results: The experimental AR vaccine showed similar efficacy after bacterial challenges since there were no significant differences in clinical symptoms, turbinate lesions, lung lesions and daily body gain between the two vaccinated groups. Discussion and conclusion: The replacement of recombinant fragments of PMT to P. multocida toxin in AR vaccine provided same protection as commercial vaccine after bacterial challenges. However, high yield and simple processing of recombinant fragments of PMT from E.coli cells to replace purified P. multocida toxin in AR vaccine will dramatically reduce the cost of vaccines and simplify the antigen preparation.