Productivity, Bioconversion Capacity, Protein and Fat Contents of Black Soldier Fly Larvae (Hermetia illucens) Fed with Jatropha Curcas Pressed Cake

: The use of black soldier flies (BSF) for biofuel production and fish feeding is nowadays presented as an ecological alternative. Several biomasses have been used to nurture BSF, however Jatropha curcas pressed cake obtained from biofuel production using jatropha seeds is a nutrient-rich biomass that has not yet been fully used as feed for BSF, probably due to its toxicity (not used in animal feeding). The aim of this study was to assess the bioconversion of this cake by black soldier flies ( Hermetia illucens ) following different detoxification treatments. The study was conducted in a greenhouse. Three detoxification treatments were applied on Jatropha curcas pressed cakes (whitch was obtained by cold pressing of Jatropha cusas seeds with a residual oil content of 24.64±0.05%): the treatments consisted of a control, thermal, biological and thermo-biological treatments. Resulting cake samples were used to feed 4 treatments of 550 BSF larvae in each. Each treatment had 4 repetitions, making a total of sixteen repetitions. The BSF larvae were four-day-old and were fed with 90 g of cakes every 4 days during 15 days. Assessed parameters included survival rate of larvae, meal reduction rate, bioconversion rate, organic matter, fats, crude protein, and ash contents of larvae. Results showed that the highest (p>0.05) larval survival rate (98,42±1,22%) was obtained with the biological treatment. The best bioconversion rate (37.1±60.68%) was recorded with the control treatment. No significant difference was observed between treatments with regard to organic matter (94.25±0.13%), fats (32.08±0.25%), crude protein (45.33±0.14%) and in ash (5.75±0.13%) contents. It was concluded that Jatropha curcas cakes , although toxic for monogastric, are appropriate feed material for black soldier fly larvae and can be used without any prior detoxification treatment.