Protection of piglets against atrophic rhinitis by vaccinating the sow with a vaccine against Pasteurella multocida and Bordetella bronchiseptica

The efficacy of a new vaccine against atrophic rhinitis in pigs was tested in the Netherlands and Denmark. The vaccine contained protein do (a truncated Pasteurella multocida toxin which is immunogenic and nontoxic), inactivated Bordetella bronchiseptica whole cells, and an adjuvant. The sows were either vaccinated intramuscularly with 2 ml of the vaccine at six to eight and two to four weeks before expected farrowing or left unvaccinated as controls. All the piglets were challenged intranasally with B bronchiseptica when three to seven days old and with P multocida three to four days later. Pigs born to the vaccinated sows performed significantly better than pigs born to the control sows when judged on growth, average daily weight gain and snout scores. The challenge organisms were reisolated more frequently from the control pigs than from the pigs in the vaccinated group. The vaccinated sows and their progeny developed high titres of antibodies against B bronchiseptica and P multocida toxin.