Thesis cover_Chia SY_2019.jpeg

Black soldier fly larvae as a sustainable animal feed ingredient in Kenya

PhD Thesis,
S.Y. CHIA
Wageningen University & Research, Netherlands
Defense date: 20 December 2019

Pig, poultry and fish farming are among the fastest growing agribusiness activities in East Africa, but the high costs of ingredients of major feed protein, including fishmeal, hampers growth of smallholder production. Interest in insects as an alternative feed protein source is growing. Black soldier fly (BSF) Hermetia illucens (Diptera: Stratiomyidae) is the most common insect species reared for animal feed. BSF larvae exploit a wide variety of substrates, including organic side streams, thus upgrading low-grade substrates into a high-quality protein source; BSF is not considered as a pest or vector of diseases. These attributes make it an attractive insect species for mass production.

My PhD thesis explored the potential of BSF as a novel feed ingredient in Kenya. For insect-based feed to make a substantial contribution in substituting the conventional protein-rich fishmeal and soybean meal, large quantities of insect biomass are required, which makes insect mass rearing an inevitable step. I reviewed how inclusive business for smallholder farmers through insect farming in an agribusiness value chain may be promoted and assessed farmers’ knowledge and willingness to pay for insect-based feed. Larvae of BSF were reared on agro-industrial by-products composed of brewers’ spent grains, brewer’s yeast and cane molasses, and subsequently fed to pigs to determine the effect on their growth.

The results show that farmers are aware of insects as feed and are willing to use insect-based feed. Fishmeal has been replaced up to 100% with BSF larvae in feeds for growing and finishing pigs, demonstrating that these larvae are a suitable alternative to fishmeal with a beneficial return on investment, growth and carcass weight.

This thesis provides valuable insights into the suitability of combining agro-industrial by-products for producing BSF larvae. These results are relevant to animal feed producers seeking to include insect meal in their feed formulae, to smallholder BSF farmers that either generate a circular production on-farm or sell BSF to feed millers. Therefore, this research contributes to sustainable and economically viable livestock feeding systems.

https://doi.org/10.18174/502357

https://edepot.wur.nl/502357