Abstract
Yellowfin seabream (Acanthopagrus latus) was basal fed supplemented with low (Mus1: 100 mg/kg) and high (Mus2: 200 mg/kg) doses of lysozyme (200 U/mg) diets, compared to a control group (Mus3: basal fed with no lysozyme) to evaluate lysozyme as an antibiotic alternative. Comprehensive analyses (composition, texture, histological, and untargeted metabolomics) revealed lysozyme promoted growth, muscle development, and flesh quality. Lysozyme supplementation enhanced ash and carbohydrate accumulation significantly (p < 0.05). Fish in the Mus1 group showed larger muscle fibers and increased myotome density. Metabolomics identified significant shifts in organic acids, lipids, and aromatic compounds. Mus2 enhanced mucosal immunity and retinal accumulation, while reducing fat deposition. Mus1, with a lower lysozyme dose, showed enrichment of the tricarboxylic acid cycle (TCA) cycle activity, accumulating beneficial organic acids (citric and malic acid) and nutritionally critical fatty acids (EPA and DHA), improving muscle quality. This study provides valuable insights into the effects of dietary lysozyme supplementation on yellowfin seabream, with potential applications for optimizing aquaculture practices and identifying key biomarkers for fish health and growth to improve muscle quality and flavor.