Reduction of salmonella contamination in pork carcasses by vaccination
Two field studies and one laboratory challenge were performed to evaluate of vaccination with a live, avirulent Salmonella choleraesuis vaccine (Enterisol® SC-54) to provide cross protection, reduce the level of internal culture and fecal shedding of multiple serovars of Salmonella. Barns of grow-finish pigs were vaccinated orally, via drinking water, or left as matched controls in the field studies. Ileocecal lymph nodes and spiral colon fecal material were collected at the abattoir from field studies. Three week old pigs were vaccinated intranasally and challenged at five weeks of age in the laboratory study. Internal organ culture and fecal shedding were measured two weeks following challenge with S typhimurium. In all three studies, vaccinated pigs had significantly lower culture prevalence of non S choleraesuis serovars (p<0.05), and reduced fecal shedding in following laboratory challenge (p<0.05). A nominal (p=0.07) trend to improved growth rate following laboratory challenge with S typhimurium challenge was also detected.