Manipulation of plasma uric acid in broiler chicks and its effect on leukocyte oxidative activity

1 Division of Animal and Veterinary Sciences, West Virginia University, Morgantown 26506-6108; and 2 Department of Pharmacology and Toxicology, Robert C. Byrd West Virginia University School of Medicine, West Virginia University, Morgantown, West Virginia 26506 Birds have high metabolic rates, body temperatures, and plasma glucose concentrations yet physiologically age at a rate slower than comparably sized mammals. These studies were designed to test the hypothesis that the antioxidant uric acid protects birds against oxidative stress. Mixed sex broiler chicks (3 wk old) were fed diets supplemented or not with purines (0.6 mol hypoxanthine or inosine). Study 1 consisted of 18 female Cobb × Cobb broilers that were fed purines for 7 days, whereas study 2 consisted of 12 males in a 21-day trial. Study 3 involved 30 mixed sex broilers that were fed 40 or 50 mg allopurinol/kg body mass (BM) for 21 days, a drug that lowers plasma uric acid (PUA). PUA and leukocyte oxidative activity (LOA) were determined weekly for all studies. For study 2 , pectoralis major shear force, relative kidney and liver sizes (RKS and RLS), and plasma glucose concentrations were also determined. In study 1 , PUA concentration was increased three- and twofold ( P