A Biotechnological Approach to Insect Waste Valorization: Silkworm Pupae as a Functional Feed Ingredient for <i>Pangasius pangasius</i>, Improving Growth and Physiological Responses

The rising cost of fish meal and soybean meal for aquafeeds has encouraged researchers to look for alternative protein sources. To find an alternative, this study was designed to replace soybean meal with silkworm pupae meal. An experimental feeding trial of 75 days was conducted on Pangasius fingerlings to assess the effects of partially substituted soybean meal with silkworm pupae meal (SWPM) on growth performance, antioxidant activity, and digestive enzymes. Four isonitrogenous diets were made with 0% SWPM as control and 25%, 50%, and 75% silkworm pupae meal as experimental diets. The fingerlings were given control and experimental diets at 3% of their body weight. The study found that the groups given SWPM at 25% and 50% concentration had the best growth performance, feed efficiency (up to 0.80±0.00%), and feed conversion ratio (up to 1.24±0.00%). Both groups showed increased highest final weight (up to 22.25±0.76), weight gain % (up to 95.03±0.35%), and improved survival growth rates (100%) as compared to the control. The control and treated groups (25% and 50%) exhibited significant differences (p < 0.05) in terms of antioxidant activity and digestive enzymes. The histomorphometry examination revealed no damage in hepatic tissues, intestinal villi, and podocytes as a result of the inclusion of silkworm pupae meal. The data suggest that silkworm pupae meal may serve as an adequate replacement for soybean meal, up to 50%, without negatively impacting the growth responses, antioxidant, and digestive enzyme activities of Pangasius.