The objective of this work was to evaluate the effect of supplementing short-chain fructo-oligosaccharides (scFOS) combined or not with live yeast Saccharomyces cerevisiae Sc 47 on weanling pigs challenged with Escherichia coli F4+. We allocated ninety-six piglets to four experimental diets: control (CTR); supplemented with scFOS (5 g/kg Profeed® P95) (scFOS); S. cerevisiae Sc 47 (1 g/kg Actisaf® Sc 47 HR +) (YEA); or both (SYN). Parameters included: performance; E. coli F4+ detection; fermentation activity; inflammatory biomarkers; and ileal histomorphology. Our results showed that supplementing scFOS was able to reduce the incidence of diarrhea, and both supplements were able to lower counts of EHEC along the gut. Supplementing scFOS was mostly associated with changes in the gut ecosystem and increases in the lactobacilli population, while S. cerevisiae Sc 47 registered increases in the numbers of ileal intraepithelial lymphocytes. The synbiotic mixture showed the lowest diarrhea incidence and fecal scores, benefiting from complementary modes of action and possible synergistic effects due to a hypothesized yeast-LAB cross-feeding phenomenon in the foregut. In conclusion, our results evidence that supplementing scFOS or Saccharomyces cerevisiae Sc 47 is efficacious to fight post-weaning colibacillosis, and combining both could be beneficial in high-risk scenarios.
Keywords: Escherichia coli F4+; Saccharomyces cerevisiae; fructo-oligosaccharides; prebiotic; probiotic; synbiotic; weaning piglet.