There is a growing demand for alternative feed ingredients to reduce dependence on marine ingredients. Black soldier fly and hemp protein meal are novel ingredients, and their utilization in Russian and Siberian sturgeon is limited, requiring further investigation. Hence, this study to determine the compositional and nutritional availability of both Black soldier fly and hemp protein meal becomes vital in Siberian and Russian sturgeon.
In a complete randomized design, a basal diet and four test ingredients were evaluated with three replicate tanks per diet. The four test ingredients (Black soldier fly, Hemp protein meal, Krill, and Fishmeal) were substituted at 300 g/kg for 300 g/kg of the basal diet (30:70 w/w test ingredient:basal diet). Yttrium oxide (Y2O3) was used as an inert marker and incorporated in the basal diet at 1% apparent digestibility/availability coefficients (ADCs). Fecal samples from both fish and feed were collected and analyzed, and apparent digestibility coefficients were calculated based on the ratios of nutrients and markers in the feces and formulated feed. The proximate compositions of the four ingredients and five test diets are presented in Table 1. Comparing the nutritional values of the test ingredients, Black Soldier fly meal had the highest dry matter content at 95.9%, while the highest crude protein was observed in Fishmeal at 88.9% and Krill meal contained the most fat at 14.4%.