Replacement of fish meal with amphipoda meal in diets of juvenile Nile tilapia (Oreochromis niloticus)

This study examines the effects of replacing fishmeal, the primary protein source in the aquaculture sector, with amphipods, which are fouling organisms commonly found in mussel ropes and tuna nets in marine aquaculture systems, on growth performance, antioxidant enzyme activities, digestive enzyme activities, and body composition of Nile tilapia (Oreochromis niloticus) juveniles. For this purpose, diets as isonitrogenic (35.4%) ve isolipidic (2.7%) containing different proportions (0%, 50%, and 100%) as isonitrogenic (35.4%) ve isolipidic (2.7%) of amphipod meal as a substitute for fishmeal were prepared for Nile tilapia juveniles with an initial average weight of 1.88 g. The experiment was conducted in 9 aquariums, with 15 Nile tilapia juveniles in each aquarium, in a triplicate design. At the end of the 8-week trial, substituting 50% of fishmeal with amphipod meal resulted in growth performance, feed intake, visceral indices, chemical composition of fish muscle, digestive enzyme activities, and antioxidant enzyme activities that were statistically similar to the control group. However, replacing 100% of fishmeal with amphipod meal had adverse effects on growth performance, feed intake, and protein efficiency ratio compared to the control group. The results of the study indicate that substituting fishmeal with 50% amphipod meal can be used without adverse effects on growth parameters and health in Nile tilapia juveniles. To address the challenges posed by fouling organisms in the aquaculture sector and to transform these organisms into a beneficial resource, further research is needed to develop techniques for harvesting and utilizing these organisms in an environmentally sustainable manner.