Evaluating Mealworm (Tenebrio Sp.) Performance on Kenyan Agri-byproducts - Growth, Nutrition and Bioconversion

Abstract

The current study aimed at evaluating the effect of replacement of wheat bran, a popular but scarce mealworm diet with potato waste, pineapple peels and cabbage leaves for efficient rearing of Tenebrio sp. The first experimental trial involved inclusion of potato wastes on wheat bran with fresh cabbage leaves provision to supplement water supply. The second experimental trial composed of wheat bran, cabbage leaves and pineapple peels at different ratios, and wet cotton wool provision in one of the diet. Both experiments were replicated four times and repeated once. Nutritional composition of the diets and harvested larvae were analysed using standard chemical procedures. The data for the first experiment demonstrated that replacement of wheat bran with potato waste is viable, as it yields comparably high survival rate (91 – 95%), favoured efficient conversion of ingested feed and yields the highest larval crude fat and energy contents. Moreover, the larvae reared on mixtures of the two ingredients were longer and heavier than those raised on sole wheat bran and sole potato wastes. However, the crude protein, most amino acids, acid detergent fiber contents as well as feed conversion ratio of the larvae remain favoured by wheat bran. On the other hand, the data for the second experiment showed that larvae raised on wheat bran diet supplied with wet cotton wool favored all growth, bioconversion rate, fat, and energy content levels. The survival remained high across all the diets. Whereas the diet comprising wheat bran, potato wastes, pineapple peels and cabbage leaves can be used to farm the mealworms, more readily available substrates with comparable protein and ash contents as wheat bran need to be evaluated for further improvement of the diet