Pathological Studies on Bacterial Respiratory Affections In Chickens In Correlation With Its Causes At Sharkia Province

The present work was performed to study the pathologic lesions in broiler chickens infected naturally with Infectious coryza, E.coli and mixedinfection (E.coli and M.gallisepticum).Chickens infected with infectious coryza showed congestion, edemaand leucocytic infiltration in the nostrils. In the late stage, caseated materials with degenerated leucocytes and cellular debris were seen in the nasal SInuses. E.coli infected chickens showed congestion, edema and leucocyticinfiltration in the nostrils, trachea, lungs and airsacs. Serofibrinous exudate were seen in the lungs and airsacs. The liver and heart revealed congestion, leucocytic infiltration and fibrinous perihepatitis and pericarditis respectively. The kidneys shoinfiltration in addition to proliferation of reticulo-endothelial cells. No lesions appeared in the brain