For the past decade, Zimbabwe has been producing approximately a quarter of soya beans per year against national demand for food, animal feed, and industrial consumption. The gap between production and demand is met by imports from Malawi, South Africa, and Zambia. This study focuses on the larvae of Tenebrio molitor, commonly known as mealworms, as a sustainable alternative source of protein for animal feed. Conditions for breeding the mealworms in Zimbabwe were investigated and includes the composition of feed, temperature, light preference, air circulation, and relative humidity, with a special focus on mealworms’ survival rate, growth performance, and development rate. The effect of the composition of feed on the growth performance was investigated by dividing the mealworms into five groups of 10 g each (approximately 100 mealworms) and exposing them to different dietary groups. Mealworms were then fed with the best-selected feed and the effects of relative humidity, temperature, oxygen, and light were determined. Weekly, the mortality rate, average weight, average length, and the number of mealworms that developed into pupae were recorded for each group. The results showed that the best feed composition was wheat bran and carrots with average weight and length of mealworms of 117 mg and 33 mm respectively, development rate of 64 %, and survival rate of 98 %. Generally, mealworms showed effective growth, development rate, and high survival rate when fed with wheat bran and carrots, at 28 ºC and 80 % humidity, in the absence of light and the presence of air.
