EFFECTS OF FISH MEAL REPLACEMENT BY WHEAT GLUTEN IN DIETS FOR RAINBOW TROUT Oncorhynchus mykiss ON GROWTH RATE, BODY COMPOSITION AND DIGESTD3ILITY

摘要

Within the animal husbandry sectors, aquaculture is now the largest consumer of fish meal and fish oil as key dietary ingredients for carnivorous fish and crustaceans. The availability offish meal and fish oil for feed production is one of the major constraints for the growth of aquaculture and its future role as a food supplier to human society.Wheat gluten is a good protein carrier with about 70-80% of crude protein content and, in this study, wheat gluten properly enriched with two essential amino acids, lysine and arginine, was tested as a potential substitute of standard fish meal diets forrainbow trout {Oncorhynchus mykiss Walbaum). For this purpose, four isonitrogenous (460 g kg~(-1)), isolipidic (180 g kg~(-1)) and isoenergetic (on the basis of the digestible energy) diets were formulated: a test diet based on wheat gluten plus essential amino acids (WG+EAA), a standard control [100% fish meal protein (FM)], a positive control based on fish meal enriched with the same essential amino acids of the test diet (FM+EAA), and a negative control [100% wheat gluten protein (WG)]. The experiment consisted of 8 weeks feeding trial with a group of 10 rainbow trout fingerlings for each aquarium and four replicates for each diet, making it a total of 160 fish with an average weight of 16.19 ± 0.05 g which were setup for the trial.