CROSS-PROTECTION OF SWINE AGAINST SALMONELLA-CHOLERAESUIS ENDOTOXIN CHALLEN GE

Normal specific pathogen free feeder pigs were actively immunized with Re-1 7 mutant Salmonella typhimurium bacterin-toxoid and their clinic al responses to intravenously administered Salmonella choleraesuis end otoxin statistically compared to responses of control (non-vaccinated) pigs. Anti-core-antigen antibody titers were measured in serum collec ted before the initial antigen injection and 10 days following the boo ster injection and statistically compared. There were significant diff erences (P < 0.05) between control and vaccinated pigs in terms of bot h the clinical responses to endotoxin challenges and titer measurement s of serum samples taken before the initial injection and 10 days foll owing booster. It was concluded that the vaccinates' reduced clinical responses to endotoxin challenge were due to their increase in serum a ntibody titers.