Revealing improvement mechanism of yak meat quality by dietary with Codonopsis pilosula stems and leaves based on transcriptomics and metabolomics

(CPSL) are commonly treated as agricultural waste, yet they are rich in antioxidants and other bioactive compounds. In order to explore their applicability in livestock feeding, a systematic evaluation was conducted on the dose-dependent effects of CPSL on yak production traits and meat characteristics. A total of forty yaks were randomly allocated into four experimental groups, including a control group fed a basal diet and three treatment groups receiving the basal diet supplemented with 0.5%, 1.0%, or 2.0% CPSL. Results indicated that the 2.0% CPSL supplementation group exhibited the highest net meat yield while significantly improving meat processing suitability. Through transcriptomic profiling, 13 genes were found to be differentially expressed between the control and CPSL-treated groups, with functions related to myofiber formation and energy metabolic processes. A marked upregulation of insulin-sensitizing gene 1 (INSIG1) and arginase 2 (ARG2) was observed specifically in the group receiving the intermediate CPSL dose. Metabolomic profiling further revealed that 81 shared differentially abundant metabolites were primarily involved in the AMPK signaling and oxidative phosphorylation pathways. Collectively, CPSL not only fortifies yak beef production by optimizing growth and slaughter performance but also significantly enhances meat tenderness and processing adaptability through regulating core mechanisms governing redox hubs and energy metabolism. These findings offer novel insights into the high-value utilization of CPSL as a feed additive.