Compound diets formulation and Hermetia illucens larvae performance

Summary

The POULTRYNSECT Work Package 1 “Optimization of Hermetia illucens rearing protocols” aims to rear black soldier fly larvae (BSFL) for the poultry feeding trials in WP2. The WP is divided into four different tasks. The first two tasks concern to adjust the nutritional composition of the BSFL by testing different diet formulations for BSFL with by-products from the agri-food chain. This report joins the preliminary results obtained from the in vivo trials
performed with Hermetia illucens (INAGRO) for deliverable 1.1 and 1.2. Raising BSFL from their neonate stage to larvae of a Harvestable size is not rocket science.
However, to do this consistently on a feed composed of by-products from the agri-food chain with varying composition and properties, and meanwhile keeping feed conversion, larvae size, nutritional composition and harvestability of the final product consistent can be rather challenging.
Potential feedstocks of different origin were collected and analysed for their macro nutritional content in order to make mixtures that are more or less in line with the requirements of BSFL as they are currently presumed optimal.
Black soldier fly larvae can be reared on an array of different by-products from the agri-food chain as long as their nutritional needs are met to some extend and the physical properties of the feed are hospitable for the larvae. However, using a different diet might result in larvae with a different composition. Especially fat content seems to vary strongly between diets.
Especially when the diet is rich in non-fibre carbohydrates the larvae seem to incorporate it into fat.
For the poultry trials larvae of consistent quality will need to be reared over prolonged periods.
Due to the inherent nature of agricultural by-products they are only available seasonally and often only for short periods. As for retailer waste, it is very variable in composition and also seasonally dependant. To have controlled conditions for the poultry feeding trials its seems therefore necessary to use a control feed for the larvae, preferably a feed that can be reproduced in other BSFL rearing facilities.