Two hundred and forty 1-d-old Arbor Acre female broilers were used to study the effects of alfalfa flavonoids (AF) on broiler performance, meat quality, and gene expression. Chicken were fed with basal diet supplemented with AF at 0, 5, 10, or 15 mg kg −1 diet for a period of 42 d. Growth performance, meat quality, antioxidant effect and lipoprotein lipase (LPL), adipose triglyceride lipase (ATGL), peroxisome proliferator-activated receptor γ (PPARγ), and fatty acid synthase (FAS) gene expressions were investigated. Results showed that AF inclusion in the diet enhanced the body weight (BW) at 42 d of age and the average daily gain from 0 to 42 d, decreased the total cholesterol (TC) and low-density lipoprotein cholesterol (LDL) levels and increased HDL level in the serum, enhanced the superoxide dismutase (SOD), catalase (CAT), total antioxidant capacity (T-AOC), and glutathione peroxidase (GSH-Px), and decreased the malondialdehyde (MDA) concentrations in the serum. Also, AF supplementation decreased the abdomen fat rate, marble, and the drip loss and storage loss after the storage for 96 h. Gene expressions' results showed that AF inclusion decreased the FAS expression and increased the LPL, PPARγ, and ATGL expressions in the liver and adipose tissues, especially when the AF inclusion level was 15 mg kg −1 diet. These results indicate that AF were found to be effective for average daily gain and breast percentage promoting, meat quality and antioxidant activity improvement via upregulating the LPL, ATGL, PPARγ, and downregulating the FAS expression in adipose and liver tissues.
