Looking for Possible Benefits of Combining Short-Chain Fructo-Oligosaccharides (scFOS) with Saccharomyces cerevisiae Sc 47 on Weaned Pigs Orally Challenged with Escherichia coli F4(+)

SIMPLE SUMMARY: Despite the use of antimicrobials in livestock being reduced in recent years, they are still widely used in swine production. These therapeutic products are commonly prophylactically used via feed or water to prevent disease and maintain productive indexes, particularly during critical periods when animals usually suffer from pathogen infections, such as post-weaning colibacillosis. However, there is an urgent need to avoid using these drugs due to increased antimicrobial resistance. Different probiotics and prebiotics are effective in preventing or limiting the disease, constituting possible alternatives. Still, there is scarce information regarding the potential benefits of combining both strategies through a synbiotic approach. In this study, we hypothesize that combining short-chain fructo-oligosaccharides (scFOS) and live yeast Saccharomyces cerevisiae Sc 47 could turn in an effective synbiotic to fight post-weaning colibacillosis in piglets due to complementary and/or synergistic effects. The objective of this work is to evaluate the effect of supplementing a blend of scFOS, live yeast Saccharomyces cerevisiae Sc 47, or their combination, on the health of weanling pigs orally challenged with enterotoxigenic Escherichia coli F4(+). Our results show that these products’ mechanism of action could be slightly different; therefore, a beneficial effect could be expected from their synbiotic supplementation. ABSTRACT: 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.