Potentials of animal, crop and agri-food wastes for the production of fly larvae

Abstract

Fly larvae, in particular those of house fly (Musca domestica) and black soldier fly (Hermetia illucens), are increasingly considered for animal feed worldwide. A simple way to produce fly larvae is to expose suitable substrates to attract adult flies that will lay eggs in the substrates from where larvae will be subsequently extracted. This study aims to evaluate the potential of animal manures and agri-food wastes for maggot production and to identify the fly species developing in the substrates. Experiments were conducted in the Republic of Benin. Twenty-six substrates were left uncovered for 10 hours and maggots were harvested after four days. Fresh substrates were then added to residual substrates and left uncovered for another 10 hours for another production cycle. In total, three production cycles were monitored. In the first cycle, nearly 100% of the flies were house flies but black soldier flies appeared in the following cycles. The result showed that crop and agri-food substrates produced more larvae than manures. The highest yield at the first production cycle was obtained with the mixture of soybean bran and maize grain pericarp. Maize bran, pig manure and chicken manure also showed potential for maggot production. Other substrates such as cow and sheep/goat manure produced nearly no maggot when used alone but the amount of larvae substantially increased when attractants such as chicken offal were added, or when mixed with pig and chicken manure. Production decreased with the production cycles for the majority of substrates, except for mixtures based on spent grain and pineapple grain, which produced a large amount of larva at the second harvest. The activity of maggots led to temperature elevation and reduction of substrate biomass. This study showed that several substrates, in particular soybean bran, maize bran, pig manure and chicken manure show potential for maggot production.

Substrates most preferred for black soldier fly Hermetia illucens (L.) oviposition are not the most suitable for their larval development

“…No eggs were, however, deposited on chicken manure as reported by Ewusie et al (2019) and Sripontan et al (2017). In another study, Ganda et al (2019) exposed a high number of substrates to houseflies and BSF, although the eggs laid on each substrate were not counted, the quantity (weight) of larvae collected from the substrates provides a good indication of their attractiveness, however, results of this study showed that differences among substrates are much lower in larval performances than in oviposition rates. Ganda et al (2019) obtained much more BSF larvae from agri-food wastes such as maize bran and soybean bran than from pig or chicken manure, which corroborates the results of this study.…”

“…This suggests that BSF larvae production systems based on adult rearing for egg production can run with a large variety of substrates, thus the selection of the substrates to be used will largely depend on their availability and cost. In contrast, in systems based on natural oviposition, the choice of the substrate is much more critical and the addition of attractants should be considered, as practised in house fly larvae production systems (Koné et al, 2017;Ganda et al, 2019).…”

Insect and Hydroponic Farming in Africa: The New Circular Food Economy

“…One kilogram of dry organic waste can be turned into 150 to 200 grams of fresh housefly larvae. Moreover, the larvae's short life cycle limits the amount of substrate it can consume; therefore, the same substrate may be used for larvae production for two cycles (Ganda et al 2019).…”

The Role of Flies as Pollinators of Horticultural Crops: An Australian Case Study with Worldwide Relevance

“…Dipterans such as the black soldier fly, Hermetia illuscens Linnaeus 1758 (Stratiomyidae), the house fly (M. domestica) and several blowflies, including Ch. megacephala, are already being used on a large scale to reduce bio-waste streams [211,212].…”