The effect of dietary supplementation with varying levels of sodium acetate  on lipid metabolism and muscle quality in yellow feathered broiler chicken
Short-chain fatty acid salts are known to influence lipid metabolism, yet the specific impact of dietary sodium acetate on adipose deposition and flavor profile in yellow-feathered broilers remains to be fully characterized. This study evaluated the effects of graded sodium acetate supplementation (0%, Con;0.15%, L; 0.30%, M and 0.45%H) on lipid metabolism, and meat quality over a 70-day feeding period in 640 one-day-old male broilers.While supplementation did not significantly alter overall growth performance metrics (average daily gain, feed intake, and feed conversion ratio), it elicited a dose-dependent modulation of lipid deposition and composition. Notably, the 0.30% sodium acetate group demonstrated a significant increase in serum triglyceride (TG) concentrations and intramuscular fat (IMF) content in the breast muscle (P < 0.05). This group also exhibited elevated levels of monounsaturated fatty acids (C18:1n9) and saturated fatty acids,(C18:0) (P < 0.05),alongside enhanced concentrations of sweet and umami amino acids and a reduction in cooking loss.Hepatic analysis revealed increased concentrations of total cholesterol (TC) and TG, accompanied by upregulated expression of lipogenic and modulatory genes (LXRa, SREBP-1c, ACC, FAS, SCD1, FABP4) in the 0.30% and 0.45% sodium acetate groups (P < 0.05). Cecal microbiota profiling indicated an enrichment of beneficial taxa such as Shuttleworthia. However, the highest sodium acetate dose (0.45%) was associated with an elevated abdominal fat rate and increased liver function indices (ALT, AST, TBIL), suggesting potential metabolic overload.Liver metabolomic analysis of the 0.30% sodium acetate group identified significant enrichment of metabolites involved in cofactor biosynthesis pathways. Collectively, these findings suggest that a 0.30% dietary sodium acetate supplementation optimally enhances intramuscular fat deposition and flavor attributes, potentially mediated by alterations in gut microbiota composition, hepatic lipogenic activity, and cofactor metabolism. In contrast, higher supplementation levels may impose hepatic metabolic stress. This study underscores the importance of precise sodium acetate dosing to improve meat quality while safeguarding metabolic health in poultry production.