Increasing the calcium content of mealworms (Tenebrio molitor) to improve their nutritional value for bone mineralization of growing chicks

The purpose of these studies was to determine the husbandry variables that optimize the Ca content of mealworms (Tenebrio molitor) and to determine th e bioavailability of this Ca for bone mineralization in chicks that consume the mealworms. To determine the optimal level of Ca in the substrates used in short-term (< 14 days) holding of mealworms and to determine the length of time that mealworms should be exposed to high-Ca substrates, mealworms were placed in either a wheat bran or a chicken starter substrate supplemen ted with 0, 4, 8, or 12%, Ca from CaCO3. The mealworms were harvested after 0.5, 1, 2, 3, 4, 7, or 14 days. The Ca content of the mealworms was greate st with the use of chicken starter and increased linearly with the Ca conte nt of the substrate. In general, the Ca content of the mealworms increased during the first 24 hr and decreased after greater than or equal to1 wk, es pecially at the higher levels of Ca supplementation. The chicken starter al so resulted in higher levels of vitamin B in mealworms. Mealworms held in w heat bran with 8% Ca were fed to growing chicks. Ca bioavailability was cal culated from the chicks' bone ash. The Ca in these mealworms was 76% as bio available as the Ca in oyster shell.