Effects of dietary supplementation with chlorogenic acid on growth performance, antioxidant capacity, and hepatic inflammation in broiler chickens subjected to diquat-induced oxidative stress

This study was conducted to investigate the protective effects of chlorogenic acid (CGA) on broilers subjected to (DQ)-induced oxidative stress. In experiment 1, one hundred and ninety-two male one -day-old Ross 308 broiler chicks were distributed into 4 groups and fed a basal diet supplemented with 0, 250, 500, or 1,000 mg/kg CGA for 21 d. In experiment 2, an equivalent number of male one-day-old chicks were allo-cated to 4 treatments for a 21-d trial: 1) Control group, normal birds fed a basal diet; 2) DQ group, DQ-chal-lenged birds fed a basal diet; and 3) and 4) CGA-treated groups: DQ-challenged birds fed a basal diet supple-mented with 500 or 1,000 mg/kg CGA. The intraperito-neal DQ challenge was performed at 20 d. In experiment 1, CGA administration linearly increased 21-d body weight, and weight gain and feed intake dur-ing 1 to 21 d (P < 0.05). CGA linearly and/or quadrati-cally increased total antioxidant capacity, catalase, superoxide dismutase, and glutathione peroxidase activities, elevated glutathione level, and reduced malondialdehyde accumulation in serum, liver, and/or jejunum (P < 0.05). In experiment 2, compared with the control group, DQ challenge reduced body weight ratio (P < 0.05), which was reversed by CGA adminis-tration (P < 0.05). DQ challenge increased serum total protein level, aspartate aminotransferase activity, and total bilirubin concentration (P < 0.05), which were normalized when supplementing 500 mg/kg and/or 1,000 mg/kg CGA (P < 0.05). DQ administration ele-vated hepatic interleukin-1b, tumor necrosis factor -a, and interleukin-6 levels (P < 0.05), and the values of interleukin-1b were normalized to control values when supplementing CGA (P < 0.05). DQ injection decreased serum superoxide dismutase activity, hepatic catalase activity, and serum and hepatic glutathione level, but increased malondialdehyde concentration in serum and liver (P < 0.05), and the values of these parameters (except hepatic catalase activity) were reversed by 500 and/or 1,000 mg/kg CGA. The results suggested that CGA could improve growth performance, alleviate oxidative stress, and ameliorate hepatic inflammation in DQ-challenged broilers.