Rice protein concentrate meal as a potential dietary ingredient in practical diets for blackspot seabream (Pagellus bogaraveo): histological and enzymatic investigation

Field and laboratory studies were conducted to evaluate the intestinal responses to partial replacement of fish meal with rice protein concentrate (RPC) in practical diets for blackspot seabream Pagellus bogaraveo. Two experimental diets were formulated to be isoproteic and isoenergetic with an increasing level of RPC (20 and 35%, respectively) and were tested against a fish meal-based control diet (RPC0). The diets showed similar features for growth performances and both intestinal histology and digestive enzymes. This study confirmed that RPC does not induce intestinal mucosa alterations in this fish. The dietary RPC supplement caused a significant increase in trypsin activity, whereas lipase activity was reduced.