Optimizing growth and promoting metabolism: Live prey impact on Odontobutis potamophila larvae

This study investigated how different live prey affect the growth, body composition, and metabolism of Odontobutis potamophila larvae using transcriptomics and qPCR. Larvae were fed Daphnia magna (C), Limnodrilus hoffmeisteri (L), Hypophthalmichthys molitrix (H), or a mixed diet (M). Groups L and M showed significantly higher weight gain and specific growth rates than C and H ( P < 0.05). Group H had the highest crude fat and PUFAs, especially n-3 PUFAs, but the lowest MUFAs. Total amino acids were significantly higher in L and M. Lipase activity increased in C and M, indicating improved digestion. Transcriptomic analysis revealed enhanced oxidative phosphorylation and PPAR signaling in M, with upregulated genes related to lipid metabolism. These results show that live prey types influence larval growth, nutrient composition, and metabolic regulation, offering insights for optimized aquaculture feeding strategies. • Mixed prey boosts larval growth, yielding highest weight gain and growth rates. • Prey type dictates lipid profiles: H. molitrix elevates n-3 PUFAs; L. hoffmeisteri enriches amino acids. • Mixed diet activates oxidative phosphorylation/PPAR pathways, linked to lipid metabolism genes. • Diet-driven enzyme shifts: Daphnia elevates lipase; Limnodrilus /mix enhance trypsin.