Oxidative stress biomarkers in evaluation of therapeutic potential of Ascorbic acidin poultry under hot Climate

Reactive oxygen species (ROS) are a type of oxygen-derived free radicals which are produced normally in cells during mitochondrial respiration and energy generation, but they are degraded and removed by cellular defense systems. When the production of ROS increases or the scavenging systems are ineffective, the result is an excess of these free radicals, leading to a condition called oxidative stress.ROS damage DNA, biomembrane lipids, proteins and other macromolecules. These phenomena contribute to the development of several metabolic dysfunctions, including cell death by causing “oxidative stress” and “oxidative damage.The detrimental effects of high ambient temperature on broiler performance have been widely documented. Feed consumption and growth rate decrease at high ambient temperature. Antioxidant status of the organism is depleted as result of heat induced oxidative stress The degree of lipid peroxidation is used as an indicator of ROS mediated damage and the concentration of MDA in blood and tissues are generally used as biomarkers of oxidative stress. In addition analyses of the activity of the enzymes glutathione peroxidase, catalase and superoxide dismutase are important in determining whether oxidative stress reactions are induced in cells and which cells or organs have been damaged. Antioxidants like ascorbic acid are free radical quenchers,and thereforealleviate the negative effect of heat stress and may stimulate the biosynthesis and secretion of antioxidant enzymes which scavenge the free radicals.