Potential use of mealworms as an alternative protein source for Pacific white shrimp: Digestibility and performance

Mealworm meal (MM) was evaluated for its potential as a future protein source for the farmed shrimp Litopenaeus vannamei. The apparent digestibility coefficients (ADC) were determined using a reference diet and a test diet that contained 85% reference diet and 15% MM, both contained 0.5% chromic oxide as an inert marker. Subsequently, considering the digestible values of MM, after six weeks of culture under clear water using five diets containing different levels of fishmeal replaced by MM (0%, 25%, 50%, 75% and 100%), the growth parameters and the whole shrimp body composition were evaluated. The values of the ADC were: 45.9% for dry matter, 66.5% for energy and 76.1% for crude protein while the ADC for essential amino acids ranged from 72% to 86%. Methionine was the first limiting amino acid in MM. Weight gain, specific growth rate, feed intake, feed conversion, survival and protein retention were not affected when fishmeal was replaced by MM (P > 0.05). The protein content of the shrimp body showed no significant differences (P > 0.05) between the treatments. However, lipid content of the shrimp body increased from 1.13% to 1.88% when fishmeal was replaced by MM. These results suggest that mealworm meal can be utilized as an alternative protein source for L. vannamei juveniles, although methionine should be added as a supplement.