Probiotic yeasts in livestock sector

The increase in livestock production systems has resulted in serious environmental impact due to emission of greenhouse gases and the possibility of transfer of zoonotic diseases to humans. Initially, antimicrobial drugs used as feed additives to overcome these challenges led to the emergence of resistant pathogens and have now been banned. The current trend in animal nutrition is to provide feed that meets nutritional needs, maintains healthy status and lowers the possibilities of infection. Probiotics have been described by many researchers to be an effective natural strategy towards improving an animal's health and performance. Probiotics are live microorganisms which confer health benefits on the host by modifying the intestinal microflora and probiotic yeasts have been used for decades as microbial feed additives. This review focuses on the positive influence of yeast supplementation in animal feed and some of the mechanisms by which these benefits are achieved have also been discussed.