Fish skin pigmentation in aquaculture: the influence of rearing conditions and its neuroendocrine regulation

Skin pigmentation pattern is a species-specific characteristic that depends on the number and the spatial combination of several types of chromatophores. This feature can change during life, for example in the metamorphosis or reproductive cycle, or as a response to biotic and/or abiotic environmental cues (nutrition, UV incidence, surrounding luminosity, and social interactions). Fish skin pigmentation is one of the most important quality criteria dictating the market value of both aquaculture and ornamental species because it serves as an external signal to infer its welfare and the culture conditions used. For that reason, several studies have been conducted aiming to understand the mechanisms underlying fish pigmentation as well as the influence exerted by rearing conditions. In this context, the present review focuses on the current knowledge on endocrine regulation of fish pigmentation as well as on the aquaculture conditions affecting skin coloration. Available information on Iberoamerican fish species cultured is presented