Carotenoids in ornamental fish farming

      The aquaculture industry has grown dramatically in recent years, with a multimillion-dollar market. There are a variety of freshwater fish, marine fish, mollusks, and ornamental fish cultivated in this industry. The pigment and coloring of ornamental fish are important characteristics for marketing. In edible fish, carotenoids are responsible for the pigmentation of body tissue, while in ornamental fishes, they are responsible for the coloring of the skin. Fish are unable to synthesize carotenoids and are dependent on their diets to obtain the pigments they require. In closed environments, artificial and formulated feeds play a critical role in successful fish farming. A variety of natural carotenoid sources are widely used for enhancing the pigment of ornamental fish, including non-photosynthetic tissues of higher plants, microalgae, seaweed, red yeast and crustacean by-products (shells, carapace). Aquaculture farmers prefer natural carotenoid sources over artificial sources. For farmers, the amount of benefit gained from skin color after the end of fish feeding is important. The importance of carotenoids in ornamental fish culture has been discussed in this review.