Abstract
As a major source of high-quality protein in China, duck meat such as the renowned Beijing Duck plays a critical role in the poultry industry. Sansui duck, a prized native breed, is valued for its tender meat and rich flavor, yet molecular mechanisms underlying its meat quality remain poorly studied. This study employed metabolomics and proteomics techniques to conduct a comprehensive comparative analysis of the breast and thigh muscles from 90-day-old (90X, 90T) and 468-day-old (468X, 468T) Sansui ducks. The meat quality traits indicated that the shear force and redness (a*) were significantly higher in the 468T and 468X groups compared to the 90X and 90T groups (p < 0.05). Similarly, the shear force values of the 90T and 468T groups were significantly higher than those of the 90X and 468X groups (p < 0.05). Quantitative proteomics analysis revealed differentially expressed proteins (DEPs) significantly enriched in oxidative phosphorylation and ribosomal biogenesis pathways. Non-targeted metabolomics identified differentially expressed metabolites (DEMs) concentrated in amino acid and lipid metabolism pathways. Correlation analysis indicated that in the comparison between 90X and 468X, 18 DEPs and 10 DEMs were closely associated with fleshiness, whereas in the comparison between 468X and 468T, 23 DEPs and 19 DEMs were closely associated with fleshiness. Integrating proteomics and metabolomics data analysis, proteins such as A0A8B9TTI1, R0JRM6, and A0A8B9SQI5, along with metabolites including L-lysine, L-pyrrolidone, and γ-aminobutyric acid from lysine degradation, butanoate metabolism, and 2-oxocarboxylic acid metabolism pathways, can be proposed as key factors influencing meat quality through pathways including lysine degradation, butanoate metabolism, and 2-oxocarboxylic acid metabolism in older ducks. In contrast, the protein R0JXJ3 and metabolites choline and L-glutamine may determine meat quality differences between anatomical sites through the ABC transporter pathway. These findings provide molecular insights and potential biomarkers for genetic breeding and meat quality improvement in Sansui ducks.