A multidisciplinary study of the extracutaneous pigment system of European sea bass (Dicentrarchus labrax L.). A possible relationship between kidney disease and dopa oxidase activity level

It was found a relationship between kidney disease of farmed European sea bass (Dicentrarchus labrax L.) and dopa oxidase activity level, demonstrating the DO activity as a possible indicator for fish kidney nephrocalcinosis whose diagnosis can be, simply, highlighted by a gross examination of the farmed fishes during the autopsy. Moreover variations of dopa oxidase activity in extracutaneous pigment system have been observed with respect to environmental temperature. The comparative Femto-TA analysis of pigments isolated from sea bass kidney tissue, fish skin melanin, natural melanin from Sepia officinalis and synthetic melanin, by pointing out that fish melano-macrophages centres do contain melanins.