Does dietary inclusion of defatted yellow mealworm (Tenebrio molitor) affect growth and body composition of juvenile common carp (Cyprinus carpio)?

The objective of this study was to evaluate the effects of total and partial replacement of fishmeal with defatted yellow mealworm (Tenebrio molitor) meal on one-summer-old common carp (Cyprinus carpio) with an initial bodyweight of 97.54 g ± 51.0 g. Fish were kept in an experimental recirculating aquaculture system (9 x 250 L tanks) and fed with two experimental diets formulated with mealworm meal replacements and one control, which had 100 g/kg fishmeal without mealworm meal (MWM0). In the first treatment, 50% of fishmeal was replaced with mealworm meal (MWM50). In the second treatment, fishmeal was replaced totally with mealworm meal (MWM100). Fish were fed three times per day at 3.0% of fish biomass. After six weeks of the experimental period, growth performance, nutrient utilization, body composition, and biometric indices were compared. The results revealed that the growth performance of common carp was not affected significantly by the inclusion level of mealworm meal. However, the highest weight gain was observed in MWM100, where specific growth rate was 0.76 ± 0.10 g/day. Crude fat content of the fish body differed significantly between experimental groups and the control. This investigation demonstrated that MWM could be used as an alternative dietary protein source to replace fishmeal without adverse effects on the growth performance of one-summer-old common carp.