Fishmeal Dietary Replacement Up to 50%: A Comparative Study of Two Insect Meals for Rainbow Trout (Oncorhynchus mykiss)

Abstract

The demand of optimal protein for human consumption is growing. The Food and Agriculture Organization (FAO) has highlighted aquaculture as one of themost promising alternatives for this protein supply gap due to the high efficiency of fish growth. However, aquaculture has been facing its own sustainability problem, because its high demand for protein has been traditionally satisfiedwith the use of fishmeal (FM) as themain source. Some of themost promising and sustainable protein substitutes for FM come frominsects. The presentmanuscript provides insight into an experiment carried out on rainbow trout (Oncorhynchus mykiss)with a 50%replacement of FMwith different larvae insectmeals: Hermetia illucens (HI), and Tenebrio molitor (TM). TMshowed better results for growth, protein utilization andmore active digestive function, supported by intestinal histological changes. Liver histology and intermediarymetabolismdid not showrelevant changes between insectmeals,while other parameters such as antioxidant enzyme activities and tissue damage indicators showed the potential of insectmeals as functional ingredients.