Acute fibrinous pleuritis, lung tissue, cow

Necropsy photograph of the lung of a cow that died because of acute fibrinous pleuritis associated with inhalation pneumonia. Necropsy examination of the thoracic cavity revealed the presence of several liters of fibrinous pleural fluid. The lungs did not inflate, and samples sank in formalin. The surface of the lung is discolored with hyperemic and necrotic tissue with fibrin and fibrosis formation. The lung tissue was also malodorous, consistent with a mixed aerobic and anaerobic bacterial infection due to aspiration of rumen contents.