Objectives: Calf pneumonia is one of the most common diseases in dairy and beef herds.The aim of this research was to study Oxidative Stress in Dairy Calf Pneumonia. Materials & Methods:The oxidant and antioxidant status were investigated in calves with acute and chronic broncho pneumonia -n=15 and n=15- as well as in healthy animals -n=15-. Reduced glutathione -GSH- and glutathione peroxidase -GSH-PX- superoxide dismutase-SOD- and Malondialdehyde -MDA- and Ferric Reducing ability of plasma -FRAP- were measured in all subjects. In parallel, some haematological -erythrocyte and leukocyte counts, haemoglodinemia- and biochemical parameters -blood fibrinogen and total protein concentrations- were also determined. Results & Conclusion: Fibrinogen concentration were dramatically increased in diseased calves, but, in chronically affected animals, the elevation of fibrinogen concentration was lower than in calves with the acute disease and was associated with reduction of erythrocyte count, leucopenia and hypoproteinemia. The markers of Lipid Proxidation-MDA- were significantly elevated in diseased calves, mainly in those with chronic bronchopneumonia. The GSH concentration and FRAP gradually declined according to the disease duration. GSH-Px activities the acute and chronic form were increased and this increase during chronic bronchopneumonia than acute bronchopneumonia.These results demonstrated the occurrence of the oxidative stress in bronchopneumonia, particularly intense and coupled to a strong inflammatory reaction in the chronic form.

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