Study of liver and gut alterations in sea bream, Sparus aurata L., fed a mixture of vegetable protein concentrates

This study evaluated liver and gut alterations of gilthead sea bream, Sparus aurata L., fed diets in which fish meal was substituted by a mixture (M) of pea protein concentrate (PPC) and rice protein concentrate (RPC). Histological studies were conducted to evaluate the possible changes produced by four experimental isolipidic (18%) and isoproteic (48%CP) diets with 30%, 60% and 90% of fish meal substitution by a pea and rice mixture and compared with a control diet (0%). The results obtained in the present histological study showed significant changes especially in the case of the 90% substitution in parameters such as thickness of the layers, goblet cells and villi measurements. Structural integrity of the gut would not be significantly affected by a diet of up to 60% substitution. The alterations observed in the liver could not only be attributed to diet but also to possible individual variations.