Effect of selenium and nano-selenium applications on biological functions in aquaculture: a review

Selenium plays a crucial role in vital physiological processes for fish, by involved in many processes of cellular metabolism and increase the growth performance and health status of fish. Nano-selenium (nano-Se) has been shown to promote fish growth more than other traditional inorganic Se forms. Additionally, increased the capacity to absorb various nutrients, and provided protection from pathogens. In general, the growth, hematological, biochemical and immune characteristics of fish improved with the incorporation of dietary selenium. When fish fed small amounts, Se can also function as an antioxidant. There is a need for more research on the use of dietary Se as a supplement in the diets of various aquatic species since there are a few variables that could affect the levels of dietary Se and make it more difficult to estimate its required levels. The actual bioavailability of Se nanoparticles to fish also needs to be determined. This review have tried to evaluate and draw conclusions about the advantages of Se in various forms and its potential application as a mineral supplement to various aquatic animal's species in different biological functions.