Abstract: Selenium (Se) is an essential trace element for animals and human,it has roles in regulating growth,enhancing immunity,preventing cancer,resisting oxidation and stress,postponing aging and preventing or controlling local epidemic,etc. Sodium selenite is used as the commercial Se source supplement in animal feeds in China. But it was found that sodium selenite had disadvantage of higher toxicity,lower bioavailability and potential environmental pollution. etc. In recent years,great attention has been gradually paid to organic selenium which has lower toxicity and higher biological utilization rate. Selenium yeast has become a hot spot in animal production. The possibilities of selenium yeast as feed additive were discussed in this article.

Key words: selenium yeast; animal production; research; application