Advances in nutritional and physiological effects of β-glucan on aquatic animals

β-glucan (βG) as one type of immune stimulants shows a wide range of immunological bio-activities.Studies in aquatic animals showed that β-glucan could promote the growth performance of fish and shrimp and activities of antioxidant enzymes, effectively remove free radicals within the body, enhance the activities of immune-related enzymes, promote the synthesis of immunoglobulin, and activate the complement system and antiseptic matters to improve animals' immunity. Moreover, it could improve the gene expression level of certain immune -related enzymes and enhance the capacity of animals’resistance to infection. So far, β-glucan is the immune stimulant most in-depth researched and widely used in aquaculture, which improves animals' resistance to oxidative stress and immunity in intensive and large-scale culture, and shows a wide range of application prospects and values. In this article, the effects of β-glucan on growth performance, oxidation resistance, immunity function and anti-infection were summarized.