Across all 3 available studies (all reviews), Saccharomyces cerevisiae fermentate or postbiotic supplementation shows moderate beneficial effects on growth performance in animals, including poultry, swine, horses, and ruminants. The evidence consistently indicates improvements in feed conversion ratios, weight gain, and overall health, though no studies reported statistical significance or effect sizes specific to individual trials. The predominant effect size is moderate, but the evidence base is too small to draw firm conclusions about dose or duration.
Caveats: Evidence base is small (only 3 studies) — conclusions should be considered preliminary. All three studies are narrative reviews, not primary trials, limiting causal inference. None of the studies reported statistical significance or sample sizes, and study durations were not consistently reported. Available evidence is overwhelmingly positive — clinical literature in this area is subject to publication bias (null-result studies are less likely to be published or indexed).
The integration of postbiotics into animal feed improves growth performance, feed conversion ratios, and disease resistance in animals
Saccharomyces cerevisiae fermentate has been reported as an alternative to antibiotics in livestock production, with studies noting improvements in feed-to-weight ratio, meat quality and overall health of livestock.
The intestinal microbiota has gained increased attention ... due to its role in promoting intestinal maturation, immune system modulation, and consequently the enhancement of the health and growth performance of the host.