Use of mixture experiments to design diets for Tenebrio molitor L. (Coleoptera: Tenebrionidae) larvae

Abstract

Insects, particularly the larvae of the Tenebrio molitor beetle, are proposed as a food source since they have a high nutritional value and are easy to breed. Although researchers used different approaches to develop diets for T. molitor larvae growth, none used mixture design experiments. Therefore, this study aimed to evaluate the feasibility of using a mixture experiments design and three macronutrient sources to develop a diet resulting in the best growth for T. molitor larvae. We placed groups of fifty larvae in polycarbonate containers, fed them ad libitum one of 19 diets containing different macronutrient proportions for five weeks, and recorded the larvae’s weight and mortality every seven days, and a model was constructed for the relative weight increase (growth rate). Larvae weight rises as whey protein concentrate (protein source) increases, and soybean oil decreases. Results of survival analysis showed that the feed composition did not influence larvae survival. Mixture experimental designs could help develop adequate diets for T. molitor larvae and other insects.