Efficacy of Clostridium butyricum as probiotic feed additive against experimental Salmonella Typhimurium infection in pigs

Abstract

Salmonella Typhimurium (S. Typhimurium) infections in pigs constitute a risk for human salmonellosis. The use of probiotics may be a promising tool to reduce Salmonella infections in pigs. The present study investigated the efficacy of Clostridium butyricum (C. butyricum), at two different dosages, as probiotic feed additive against S. typhimurium infection in experimentally challenged pigs.After weaning, 35 Salmonella negative pigs were randomly divided into 4 groups;Negative control: no feed additive (n = 5), Positive control: no feed additive (n = 10), CB-H: ±2 × 106 CFU C. butyricum/g feed (n = 10), CB-L: ± 5 × 105 CFU C. butyricum/g feed (n = 10). Pigs were fed ad libitum with the experimental feed, including the probiotic feed additive according to the group, from arrival (day -7) until euthanasia (day 42). One week after arrival (day 0), pigs in the positive control group, CB-H and CB-L were orally inoculated with 2 × 108 CFU/mL nalidixic acid resistant S. typhimurium strain 112910a (1 mL/pig). Fecal excretion, serological response, intestinal carriage and prevalence of S. typhimurium positive ileocecal lymph nodes were evaluated.Under the present conditions, the probiotic feed additive C. butyricum did not significantly reduce fecal excretion, serological response, intestinal carriage and prevalence of S. typhimurium in the ileocecal lymph nodes in experimentally challenged pigs. Further research is needed to investigate the results under field conditions and to detect possible additional effects of the application of the probiotic for a longer time period.