Dose-Dependent Effects of Black Soldier Fly Larvae Meal on Growth and Health of Common Carp

The aim of this study was to evaluate the effects of incorporating Black Soldier Fly Meal (BSFLM) into the diet of two-year-old carp on growth and health status. Four concentrations of BSFLM were tested, T1-0% (control), T2-10%, T3-20%, and T4-30%, in common carp with an initial body weight of 112.06 ± 3.86 g over a 12-week feeding period. The results showed that final weight and weight gain were 17.3% (349.15 g) and 23% (233.6 g) higher in the T4 group compared to the control (298.63 g and 189.79 g, respectively). Flesh composition showed no significant changes. Hematological variations were insignificant. Oxidative stress assessment revealed increased activities of antioxidant enzymes (SOD, CAT, and GPx) alongside reduced lipid peroxidation. The counts of anaerobic microorganisms and Enterobacteriaceae in intestine increased linearly in BSFLM groups. Histological examination showed normal intestinal and hepatopancreatic morphology in the 10% and 20% BSFLM groups (T2 and T3). In contrast, the 30% inclusion level (T4) was associated with hepatocellular vacuolization and alterations in villus architecture. In two-year-old carp, dietary BSFLM induced dose-dependent responses, whereby higher inclusion levels supported weight gain but adversely affected the morphological integrity of the intestine and hepatopancreas.