Daidzein Changes Production Performance, Meat Quality, and Transcriptome of Muscle in Heat-Stressed Jinjiang Cattle

This research was carried out to assess the impact of daidzein supplementation on production performance, serum biochemical indexes, meat quality, and the transcriptome of the longissimus dorsi (LM) muscle in heat-stressed Jinjiang cattle. Twenty 20-month-old Jinjiang cattle (initial mean &plusmn: SE: 438 &plusmn: 34.6 kg of body weight) were randomly divided into two treatment groups (n = 10 per treatment): control treatment and daidzein treatment (1000 mg/kg concentrate). After a 100-day feeding trial (consisting of a 10-day adaptation period and a 90-day daidzein feeding period), blood and LM muscle samples were collected on day 100. Daidzein significantly increased the average daily dry matter intake (ADMI), the concentration of free fatty acid (FFA) and glutamic-pyruvic transaminase (ALT) in serum, and the marbling score of the LM muscle. Additionally, daidzein significantly decreased the concentration of total cholesterol (TC) and leptin in serum, along with the shear force and L* value of LM in heat-stressed Jinjiang cattle. The transcriptome analysis demonstrated that 238 differentially expressed genes (DEGs) were identified through differential expression analysis, among which 168 genes were downregulated and 70 genes were upregulated. The results of KEGG pathways showed that these DEGs were significantly enriched in pathways related to beef tenderness, including the FoxO signaling pathway, Notch signaling pathway, and regulation of the actin cytoskeleton. Daidzein significantly affected the candidate genes (FOSL1, DGKH, Gadd45G, GAL, SEMA3, TOB, FABP8, TRIB2, Nech1, and GSTA3) involved in adipocyte differentiation, as well as genes (CSTB and ACTN) related to connective tissue structure in heat-stressed Jinjiang cattle. Daidzein plays a positive role in relieving heat stress and improving beef quality in heat-stressed Jinjiang cattle.