The increasing cost and sustainability concerns associated with soybean meal (SBM) necessitate alternative protein sources for aquaculture feeds. This study evaluated graded replacement of SBM with silkworm pupae meal (SWPM; 0, 25, 50, and 75 %) combined with probiotics in Pangasius pangasius. Among ten screened probiotic strains, Lactobacillus acidophilus and Bifidobacterium bifidum showed strong antimicrobial activity against major fish pathogens. A 90-day feeding trial demonstrated that diets containing 25 % and 50 % SWPM significantly improved growth performance compared to the control, increasing final body weight from 19.83 g to 27.39 g and 28.54 g, respectively, with a concurrent reduction in feed conversion ratio from 1.29 to 1.22 (p ≤ 0.001). Antioxidant capacity was markedly enhanced, as evidenced by reduced lipid peroxidation and elevated activities of superoxide dismutase (upto 236.9U/mg) and catalase (43.9U/mg) in the liver, kidney, and intestine (p ≤ 0.001). Gene expression analysis revealed downregulation of tumor necrosis factor-alpha and interleukin-6, alongside strong upregulation of the anti-inflammatory cytokine interleukin-10 (2.1-fold) at 25-50 % SWPM, whereas 75 % inclusion induced pro-inflammatory signaling. In conclusion, dietary inclusion of 25-50 % SWPM combined with probiotics is optimal for enhancing growth, antioxidant defense, digestive efficiency, and immune homeostasis in P. pangasius, supporting its use in sustainable functional aquafeeds.
Tariq et al. (Thu,) studied this question.