The objective of this study was to evaluate the effects of different dietary crude protein levels on the growth and nutritional composition of Tenebrio molitor larval flours, considering three developmental stages.
The bioassays followed a completely randomized design (CRD) with six treatments (CP levels) and six replicates per treatment, totaling 36 experimental units. Each unit consisted of a 100 mL plastic container with 50 larvae, with initial weight and length recorded. Environmental conditions were standardized at 30 ± 2 °C, relative humidity of 70 ± 10%, and a 12 h photoperiod. Insects were kept in polypropylene trays covered with voile fabric to ensure ventilation and prevent escape. Fresh pieces of Sechium edule Swartz (chayote) were provided as a moisture source and, replaced every two days to prevent degradation and substrate contamination.
The results of this study demonstrate that crude protein (CP) levels in the diet exert a significant influence on the zootechnical performance of Tenebrio molitor, especially during the intermediate and final stages of larval development. Weight, length, and feed intake showed quadratic responses to protein variation, with stage-specific optimal points, indicating the need for differentiated nutritional strategies throughout the species’ ontogenetic cycle. Protein content in the final flour remained stable, fat content was markedly influenced by dietary protein levels and the larval developmental stage at the time of collection.
The bioassays were conducted at the Plant Protection Laboratory of the Federal University of Piauí, Professora Cinobelina Elvas Campus, located in Bom Jesus, PI, Brazil (09°04'28?S, 44°21'31?W). The specimens used (Tenebrio molitor and Zophobas morio – giant mealworm) were obtained from a continuous colony maintained at the institution under controlled conditions, following the protocols established by the Brazilian Association of Insect Breeders (ASBRACI, 2021). The data generated contribute to improving T. molitor rearing protocols and to consolidate its feasibility as a sustainable alternative for protein production.
