In 2017, EU approved use of insects in fish feed. Wild salmonids and other fish naturally feed on insects throughout their lives. Feeding farmed fish with live insects could be environmentally friendly, and provide for nutrient requirements of the fish. This project will assess the feasibility of feeding whole black soldier fly larvae to rainbow trout.
Black soldier fly larvae may contain 30-40% crude protein with the remainder consisting of fat and complex carbohydrate polymers. Amino acid profiles of these larvae correlate well with requirements of many farmed fish. Black soldier fly larvae have been evaluated as protein source in fish feed, defatted or as whole protein meals. However, producing insect protein meal, and thereafter combining it with other ingredients to a pelleted feed, involves a number of energy-demanding steps, such as drying, milling, defatting, and cooling.
Feeding fish with whole black soldier fly larvae could decrease the production cost mainly by eliminating the need for energy, while still providing for nutrient requirements of the fish. This feeding practice could be beneficial in circular food production systems, such as aquaponics systems and small-scale fish farms typically found in developing countries, but could also be applied to Swedish conditions.
In this project, whole live or whole euthanized black soldier fly larvae will be fed to rainbow trout in a pilot preference study.
The project started in 2018 and last for one year. The project is funded by SLU Aquaculture, which support cross-faculty collaborations to further strengthen aquaculture research at SLU. Read more about SLU Aquaculture, current research projects and upcoming calls.