Given the rising cost of fishmeal and its limited supply, and fluctuating qualities, alternative feed sources like insect meals are gaining attention. This study evaluated the growth performance and nutrient utilization of Heterobranchus bidorsalis fed diets containing varying levels of differently processed black soldier fly (BSFL) larvae meal. Fish were raised for 84 days, replacing fishmeal with BSFL meal at 0%, 25%, 50%, 75%, and 100% (Diets FM, BSF1, BSF2, BSF3 and BSF4 respectively).
Results indicated that both inclusion levels and processing methods significantly influenced fish growth and nutrient utilization. Treatment BSF1 (25% BSFLM) demonstrated superior body weight gain, feed conversion ratio, and specific growth rate. While replacing 50% fishmeal with BSFLM (Treatment BSF2) was economically beneficial, treatments BSF1 and BSF4 exhibited higher feed conversion ratios. Treatment BSF1 also excelled in nutrient utilization, with higher apparent net protein utilization, protein efficiency ratio, and nitrogen metabolism (Table 2).
These findings underscore the importance of considering both inclusion levels and processing methods of BSFLM in fish diets to optimize growth performance and nutrient utilization in aquaculture. Further research on alternative feed sources and feeding strategies can contribute to more efficient, productive, and sustainable aquaculture practices.