Nutritional impacts on fish mucosa: Immunostimulants, pre- and probiotics

Preventive health care by dietary manipulation has been regarded as a sustainable approach in modern aquaculture. This strategy is substantiated by remarkable evidence that nutrition is an important modulator of the fish immune system. From a plethora of feed supplements that are being utilized as health promoters in aquaculture, there are three major groups that have generated considerable attention: immunostimulants, prebiotics, and probiotics. These feed supplements vary in their modes of action in fish but their ability to boost not only the innate immunity but also the mucosal immunity positioned them as significant promoters of fish health. This chapter provides the basic concepts of immunostimulants, prebiotics, and probiotics and their contemporary importance in the health and welfare of aquacultured fish. Specifically, this chapter highlights the current understanding of the roles of each substance through dietary administration on the mucosal immunity of fish and provides a platform for the advancement and multi-contextual understanding of these feed supplements in future studies.