FREE RADICALS AND THE RELATIONSHIP WITH STRESS

Free radicals are produced continuously by normal metabolic processes, but the production rate is increased in several inflammatory diseases or other conditions. Normally the body is protected by a broad interval of defense mechanisms against the reactive oxygen metabolites and their toxic products. Imbalance between the reactive oxygen metabolites and their secure disposal can initiate lipid peroxidation and oxidative chain reactions. Transport operation that is one of the important activities of farm management is one of factors affecting the animal welfare, and creating stress in the animals. The deteriorated oxidant-antioxidant balance has been suggested to play a role in the pathophysiology of the diseases occurring after transport in cattle. Heat stress is reported to induce oxidative stress by increasing the formation of reactive oxygen species in the cells. A rise in glutathione peroxidase activity was observed as a result of adaptation mechanisms against physical stress after the prolonged exercise in humans. Sheep maintained at high density have had the weaker qualited and lower milk production. The aim of this review was to give information about free radikals and to explain the oxidant and antioxidant status during stres