A quaculture continues to be the fastest growing animal food sector and accounts for over 50% of the world's fish consumption (FAO, 2014). Increased amounts and diversity of protein and lipid ingredients are required to support the sustainable and rapid growth of this industry . Fishmeal , fish oils, and land-based options are the current source of protei ns and lipids in feeds for aquaculture, but ingredients made from in sects are being considered by the industry as an alternative ingredient . However, there is still uncertainty regarding how these novel ingredients will affect fish growth and survival throughout their life cycle .
Arctic charr is an excellent choice for development of a sustainable land-based aquaculture industry g iven its high market demand for good quality product, a high market price, and the suitability of this species for production under high densities . However, there are challenges limiting the use of this species for land-based aquaculture, including the tendency for very low fertilization and hatch success, high mortality during transition to first feeding, and a lack of optimized rearing protocols for commercial production.
The aim of this study was to investigate the use of black soldier fly (BSF, Hermetia illucens ) larvae meal as a feed ingredient for Arctic charr (Salvelinus alpinus ) aquaculture. We measured growth and reproduction (fecundity and hatch rate) of Arctic charr broodstock, and growth and survival of the fry. The Arctic char broodstock were artificially mated in such a way as to also permit the determination of heritability of acceptability of BSF as an ingredient in the feed .
Two diets were produced for this trial, a control diet and a test diet. The control diet was a locally used commercial salmon feed that met or exceeded all the known dietary requirements of Arctic charr and the test diet was formulated by replacing 20% of the fishmeal with BSF (Enterra Feed Corp., Langley, BC, Canada). Diets were pelleted by extrusion by Taplow Feeds Ltd. (North Vancouver, BC, Canada). Each diet was fed to duplicate raceways of 100 fish for 3 months prior to spawning (Year 1) and 15 months prior to spawning (Year 2). Crosses were fertilized and transferred to a lab (Fisheries & Oceans Canada, West Vancouver, BC, Canada) to assess hatch rate and early life growth . At ponding , half the progeny received the control diet and half received the BSF diet. The survival and growth of the fry were tracked for 4 months to assess the impacts of broodstock diet and fertilization success on the early-life-history performance of the fry. Protein and fatty acid profiles were measured for eggs and fry.
The results show that the feed intake, survival, and growth of the BSF diet did not significantly differ from the control diet , and BSF inclusion tended to support higher survival of fry during early life history. Thus, the use of BSF for fish diets shows great potential to support the sustainable growth of aquaculture.