A review on yeast-based prebiotics, characteristics, bioactive compounds, and their mechanism of action on growth and health parameters in poultry

Nowadays, due to the high application of antibiotics, the emergence of pathogenic microorganisms resistant to antibiotics is considered a serious threat to poultry production industry. Therefore, reducing the use of antibiotics and using antibiotic alternatives is one of the main strategies to fight antibiotic resistance. Meanwhile, yeast-based prebiotics have been proposed as one of the best alternatives to antibiotics. The most important yeast-based prebiotics include hydrolyzed yeast, partially-hydrolyzed yeast, inactive yeast, yeast cell wall, yeast extract and autolyzed yeast. Yeast-based prebiotics contain functional compounds in various concentrations such as B vitamins, beta-carotene, ergosterol, ascorbic acid, polyamines, mycosins, enzymes, beta-glucans and mannan oligosaccharides, depending on the production and processing method. Yeast-based prebiotics are resistant to the acidic and alkaline conditions of the digestive system, and by inactivating pathogenic microorganisms, improving the immune system, stimulating the growth of probiotics, helping to establish beneficial microbial flora in the digestive system, and stimulating the production of volatile fatty acids, reducing intestinal acidity, improving the growth and differentiation of intestinal villi, stimulating the production of enzymes, increasing the production of antimicrobial peptides improve the production efficiency in poultry. Prebiotics also play a significant role in reducing the feed conversion ratio and mortality in poultry production industry.