Figure 1

Gross and microscopic lesions in chicken, upper row, (a) congested lung; (b) petechial and ecchymotic haemorrhages on the air sac and epicardium; (c) pancreas with dark red areas along its length and congested blood vessels at the wall of the intestine; (d) mucosal haemorrhages in proventriculus; lower row, (e) severe congestion and edema in lung tissue; (f) mild cardiac myodegeneration; (g) necrosis of pancreatic islets; (h) haemorrhages in duodenal mucosa.