Effects of Local Feed Based on Black Soldier Fly (Hermetia illucens) Larvae Meal on Zootechnical Performance and Economic Profitability of Chrysichthys nigrodigitatus (Lacépède, 1803) Production

Abstract

This study evaluated the potential of black soldier fly (Hermetia illucens) larvae meal as a sustainable alternative to fish meal in the diet of Chrysichthys nigrodigitatus. The experiment was conducted over 56 days at the Laboratory of Hydrobiology and Wetland Research (Université d’Abomey- Calavi) with fry having an initial average weight of 8.5 ± 0.01 g. Three iso-protein (40%) and iso-lipid (10%) diets, incorporating increasing proportions of H. illucens meal as a partial substitute for fish meal, were tested in triplicate. Zootechnical performance (final weight, weight gain, feed conversion ratio: 1.98–2.03, survival > 98%, and protein efficiency ratio) showed no significant differences between treatments (p > 0.05). In economic terms, the cost of production per kilogram of fish decreased significantly (p < 0.05) with insect meal-based diets, leading to an improvement in net profit. These results demonstrate that H. illucens larvae meal can effectively replace fish meal while promoting sustainable, economically viable aquaculture adapted to the Beninese context.