Comparative Effects of Silkworm Excrement Concentrate Extract Versus Sodium Copper Chlorophyllin on Growth, Metabolic Health and Immune Response in Common Carp (Cyprinus carpio)

This study investigated the efficacy of two value-added products derived from silkworm excrement-a concentrated extract (SCE, 20:1) and sodium copper chlorophyllin (SCC)-as functional feed additives for common carp. Diets supplemented with 0.5% SCE, 1.0% SCE, or 0.1% SCC were compared to a basal control. The results revealed a distinct dose-dependent effect for SCE: 0.5% SCE was safe, while 1.0% SCE impaired growth, feed efficiency, and digestive enzyme activity. Both SCE and SCC significantly enhanced lipid metabolism, reducing hepatic lipid deposition and improving serum lipid profiles, albeit through distinct molecular pathways-SCC primarily stimulated catabolism, whereas SCE comprehensively regulated both synthesis and breakdown. Furthermore, SCE demonstrated superior, multi-targeted immunomodulatory capacity by favorably regulating inflammatory cytokine expression, an effect not observed with SCC. Although both additives boosted systemic antioxidant capacity, their specific patterns of enzyme activity and gene expression differed. In conclusion, SCE offers broad-spectrum, synergistic benefits for health modulation, while SCC provides specific, stable bioactivity, highlighting the importance of selecting the appropriate additive form based on desired functional outcomes in aquaculture.