Changes

*Clinical signs: pyrexia, lethargy, skin erythema, anorexia, severe cough and sneezing, dyspnoea, conjunctivitis, pregnant sows may abort

*Clinical signs: pyrexia, lethargy, skin erythema, anorexia, severe cough and sneezing, dyspnoea, conjunctivitis, pregnant sows may abort

*Grossly:

*Grossly:

**[[Tracheitis|Tracheo]][[Bronchi and Bronchioles Inflammatory - Pathology#Infectious causes of bronchitis or bronchiolitis|bronchitis]], airway obstruction -> [[Lungs Ventilation - Pathology#Atelectasis (Collapse)|atelectasis]]

**[[Tracheitis|Tracheo]][[Bronchitis#Infectious causes of bronchitis or bronchiolitis|bronchitis]], airway obstruction -> [[Lungs Ventilation - Pathology#Atelectasis (Collapse)|atelectasis]]

**[[Pleural Cavity & Membranes Inflammatory - Pathology|Pleura]] normal or covered with serous or serofibrinous exudate

**[[Pleural Cavity & Membranes Inflammatory - Pathology|Pleura]] normal or covered with serous or serofibrinous exudate

**[[Pleural Cavity & Membranes Inflammatory - Pathology|Pleural cavity]] filled with excess fluid

**[[Pleural Cavity & Membranes Inflammatory - Pathology|Pleural cavity]] filled with excess fluid