الملخص

Poultry coccidiosis is a major protozoa disease resulting from the intracellular (apicomplexan) parasite Eimeria . The life cycle of Eimeria include extracellular and intracellular   stages that cause a strong inflammation that damages tissue by increasing oxidative stress and lipid peroxidation, clinical symptoms seen include green, yellow, or brown bloody stools, inactivity, being off feed, losing weight, decreasing feed intake, decreasing production, emaciation, having pale wattles and comb, anemia, and dying suddenly. Gross lesions showed haemorrhagic and inflated intestine.The histopathological lesion  showed  congestion of blood vessels with loss of epithelial lining layer and   edema of  mucosal layer with Submucosal necrosis. Villi loss is associated with significant haemorrhages.Oocysts within the villi with lymphoid tissue hyperplasia.. The diagnosis can be done by gross and post-mortem lesion, microscopic examination of feces and molecular technique can be used for diagnosis of coccidiosis, to prevent and treat this condition, a variety of anticoccidial medications and vaccinations have been employed.