Conclusions
Under our study conditions, neither the inclusion of a mixture of 0.4% formic and 0.4% lactic acids nor of 1% lactulose in the feed influenced survival of Salmonella Typhimurium in the ileum and caecum of pigs challenged by direct oral challenge with high doses of Salmonella. More studies with higher treatments doses and/or under different conditions of infection would be needed to fully explore the potential of these compounds.