EFFECTS OF PARTIAL INSECT MEAL SUBSTITUTION OF FISH MEAL IN DIETS ON ENZYMATIC ACTIVITY IN DIFFERENT FARMED TELEOST SPECIES

The scientific and commercial interest of using insects as an alternative protein source to replace fish meal in fish diets is increasing. To that end, different growth trials have been conducted in three important farmed teleost species (Dicentrarchus labrax, Sparus aurata and Oncorhynchus mykiss). Herein, the enzymatic activity of metabolic (L-LDH, CS, MDH) and antioxidant (catalase, SOD, GR) enzymes in heart, white muscle, liver and intestine is presented. Generally, the enzymatic activities exhibited both distinct species specificity and tissue specificity. It appears that the insect meal based diets influenced less O.mykiss among the examined species, indicating that the water ecology may have an impact. Although all species are carnivorous, their trophic levels differ (3,3 for S. aurata; 3,8 for D. labrax and 4,4 for O. mykiss based on diet in natural habitats). Further studies on various protein translation levels such as mitogen-activated protein kinases are in progress.