Growth Performance of Acclimatized Nile Tilapia (Oreochromis niloticus; Carl Linnaeus 1758.) Fed on Black Soldier Fly and Omena Dust Under Laboratory Controlled Conditions

Growth of Nile Tilapia on BSF - Omena Diets

Aquaculture plays an important role in food security and income generation in coastal Kenya. However, the sustainability and profitability of fish farming are greatly constrained by the high cost and limited availability of quality commercial fish feeds, which account for 60–70% of total production costs. This study evaluated the growth performance of acclimatized Nile tilapia (Oreochromis niloticus) fed on two locally available alternative protein sources: Black Soldier Fly Larvae (BSFL) meal and omena (Rastrineobola argentea) dust, compared with a control commercial diet. A completely randomized design (CRD) was used under laboratory-controlled conditions at the Kenya Marine and Fisheries Research Institute (KMFRI), Mombasa. A total of 180 fingerlings of similar size were stocked in nine glass aquarium tanks and assigned to three dietary treatments: BSFL meal, omena dust, and control diet, each replicated three times. Fish were fed twice daily for 60 days at 5% body weight. Growth parameters including weight gain, specific growth rate (SGR), feed conversion ratio (FCR), survival rate, and condition factor were recorded and analyzed using one-way ANOVA. Results showed that fish fed on the control diet had slightly higher final weight and better feed conversion efficiency (FCR = 2.91) compared to BSFL (3.2) and omena dust (4.0). However, no significant differences (P > 0.05) were observed in most growth parameters among treatments. BSFL recorded the highest survival rate (90%), while omena dust showed relatively lower feed efficiency. Water quality parameters remained within acceptable ranges for tilapia culture across all treatments. The findings indicate that BSFL and omena dust can serve as viable alternative protein sources for Nile tilapia culture, with BSFL showing better performance among the two alternatives. Their use can reduce dependence on expensive commercial feeds and promote sustainable aquaculture development in coastal Kenya.