Postbiotics: Multifunctional Microbial Products Transforming Animal Health and Performance

Postbiotics, which are preparations of inanimate microorganisms and their components, have emerged as a promising functional ingredient in animal health and nutrition. Postbiotics are primarily composed of microbial cell fractions, metabolites, enzymes, vitamins, polysaccharides, and short-chain fatty acids. Unlike probiotics, postbiotics do not contain live microorganisms, which strengthens their greater stability and safety in feed/food formulations. Postbiotics offer several beneficial effects, including antioxidant, anti-inflammatory, immune-modulatory, and antimicrobial actions. They enhance antioxidant enzymes, neutralize reactive oxygen species, and inhibit lipid peroxidation, thereby protecting tissues from oxidative damage. Postbiotics also inhibit pro-inflammatory molecules like TNF-α and IL-6, while enhancing the anti-inflammatory cytokine IL-10, promoting the maturation and function of immune cells, and increasing secretory IgA production. They suppress a variety of pathogenic bacteria, including <i>Escherichia coli</i>, <i>Salmonella</i>, <i>Staphylococcus</i>, <i>Campylobacter</i>, etc., both in vitro and in vivo. Moreover, they increase beneficial gut bacteria and improve the digestion and integrity of the intestine. This article outlines the beneficial effects of postbiotics in animals including poultry, swine, canine, feline, horses, and ruminant animals, either as feed/food or as a supplement. The integration of postbiotics into animal feed improves growth performance, feed conversion ratios, and disease resistance in animals. Thus, the multifunctional benefits of postbiotics make them a valuable tool for healthy companion animals and sustainable livestock production, supporting both animal welfare and productivity without the drawbacks associated with antibiotic growth promoters.