Effect of an acidified diet on Salmonella prevalence during the last term of fattening period

Abstract The objective of this study was to determine the effect of the acidification of pelleted feed on the carriage and seropositivity against Salmonella in finisher pigs of a commercial herd. Three different diets were assayed: 0.8 % formic acid (group 1); 0.4 % lactic acid plus 0.4% formic acid (group 2) and a feedstuff without additives (group 3). One thousand pigs were includ-ed in each treatment that was administered from 19 to 26 weeks of age. Blood, faecal content and mesenteric lymph nodes were collected at slaughter (30 pigs/group). The diet including lactic and formic acids significantly reduced Salmonella seroprevalence compared to the diet without additives (p<0.05) but there were no differences on the faecal excretion or in Salmonella carriage in mesenteric lymph nodes. Our results suggest that the administration of a combination of lactic and formic acids at the levels used in this study can be helpful to reduce Salmonella prevalence in finishing pigs. Introduction Feeding strategies have shown to be effective for reducing the incidence of Salmonella in pigs when combined with other measures such as hygiene and adequate manage-ment practices. Several studies reported that meal feed had a protective effect against subclinical Salmonella infection in pigs. However, these diets have a negative effect on the productivit