Identifying safe, sustainable and affordable fish feed stuffs is a priority within aquaculture. Insect meal has been presented as a suitable alternative to fish meal and other protein sources for omnivorous fish. However, only few trials have examined the use of insect meal within fish diets and always within the context of partial substitution of the fish meal component of the diet.
As such a preliminary study was conducted to evaluate the impact of complete replacement of fish meal with insect meal in tilapia diets. Juvenile Egyptian Nile Tilapia (Oreochromis niloticus) of the Abbassa strain were feed one of four diets and monitored over 12 weeks. One diet was a control diet utilizing Fish Meal (FM) while the other three utilized either Vegetal protein (VEG) sources only, Black Soldier Fly (Hermetia illucens) larvae meal (BSF), or Black Cricket (Gryllus bimaculatus) meal (GB). All diets were formulated to be nutritionally balanced. Overall, there was no significant effect of using insect meal within tilapia diets on feed consumption and conversion efficiency, fish survival, general health or growth. The results from this trial demonstrate that fish meal can successfully be replaced by insect meal in tilapia diets, and that growth rates and FCRs will be preserved and will be comparable to the already developed vegetable-based diets. This is an encouraging result for the development of insect-based locally sourced diets for fish rearing. The more feed ingredients can be produced or sourced locally, the greater the positive impact on the aquaculture industry and socio-economic status of farmers.
However, future trials should focus on seeing if diets can be improved by optimising inclusion rates of insects in feed formulations, it is possible that a higher rate or combination of multiple insect species might create more successful and sustainable formulations