Fig. 2

Lungs from pigs that displayed clinical signs of respiratory disease prior to death. Macroscopic lung lesions. a. Acute pleuropneumonia—Macroscopic lesions include fibrinopurulent pleuritis (dotted ring), edematous lungs with multifocal to coalescing hemorrhagic and hyperemic areas (dashed ring). A. pleuropneumoniae was cultured in abundance from pleura, left and right caudal lung lobes. b Chronic pleuritis, acute pneumonia. Macroscopic lesions include fibrous pleuritis (dotted ring), and focal, dark red areas of condensed lung tissue (dashed ring). The tracheobronchial lymph nodes were moderately enlarged (continuous ring). A. pleuropneumoniae was cultured from the right caudal lung lobe; no bacteria were retrieved from the chronic pleuritic lesion