Comparative assessment of developmental parameters, proximate analysis and mineral compositions of black soldier fly (Hermetia illucens) prepupae reared on organic waste substrates

Abstract

The increasing demand for alternative feed sources for livestock has evolved, owing to quest for efficient and sustainable use of resource channeled towards achieving food security. Breeding and biomass conversion of selected insects therefore, is imperative to complement existing sources. This study investigated the developmental parameters, and nutritional composition of Black soldier fly (BSF) (Hermetia illucens) larvae reared on chicken feed (CF), brewery waste (BW), food remains (FR) and fruits’ waste (FR). Proximate compositions (%) of prepupae and substrates were analyzed for dry matter (DM), crude protein (CP), ether extracts (EE), ash, fibre and mineral composition. Data were analyzed using analysis of variance (ANOVA) tests and Tukey (homoscedasticity) using SPSS statistical package. CF recorded the highest prepupal weight (0.30 g), length (2.18 cm), and shortest development time (21 days) across the different substrates. CP content was highest in prepupa fed on CF and BW at 48.93% and 44.52% respectively (p < 0.05). The ash contents and EE of the prepupae differed significantly across the different substrates. Prepupae reared on CF were low in EE and high in ash content (4.12% and 9.24%, respectively) compared to those reared on FW (13.90% and 5.24%, respectively), BW (11.23% and 10.29%, respectively) and FR (9.52% and 5.24, respectively). BSF larvae fed on different substrates exhibited different mineral accumulation patterns, with FW resulting in the largest turnover of minerals (Potassium 46.94 g/kg). The rearing of BSF larvae can be optimized on identified organic substrates into edible biomass suitable for use as an alternative protein source.