QUESTIONS AND ANSWERS 151 



Give the post-mortem appearance of acute diffused pleuritis. 



Hypersemia, surface of the pleura is rough, lustreless and dry. 

 The exudate composed of blood-corpuscles and fibrin covers the 

 surface of the pleura like a veil. In some cases a serofibrinous exu- 

 date covers the surface with a thicker, friable, moist, loose mem- 

 brane. Purulent and hemorrhagic exudates may be present. The 

 pleuritic cavity may contain a considerable amount of a serous 

 fluid which compresses the lungs. 



Describe the post-mortem appearance of the lungs in pleuropneumonia. 

 (It is taken for granted that the interrogator is referring to 

 contagious pleuropneumonia.) This disease is characterized by 

 interstitial pneumonia with secondary hepatization of the lungs and 

 an exudative pleuritis. The cut surface shows a pale yellow net- 

 work formed by an increase in the interlobular connective tissue; 

 a clear serous fluid oozes from the cut surface. Between the network 

 of connective tissue the lung tissue is hepatized. The bronchial 

 walls show serous infiltration and their lumen contains a fibrinous 

 exudate. The pleura is lustreless, injected and covered with a 

 veil-like exudate of fibrin ; a large amount of exudate in the pleural 

 cavity. 



Give the symptoms and post-mortem lesions of hydrothorax. 



For symptoms, see diseases of the respiratory organs, page 191. 



Lesions: A large amount of a clear, light yellow, or slightly 

 turbid fluid in the thoracic cavity. The lungs show compression 

 to an extent dependent upon the amount of the fluid present. The 

 pleura may be normal or thickened and cloudy. More or less 

 congestion present. 



What is atelectasis? 



An airless condition of the lungs seen in the foetus ; also seen in 

 later life due to pressure of a pleural effusion or blocking of the 

 smaller bronchial tubes with mucus. 



Describe the structural changes in the nervous and muscular tissue in 

 a case of roaring. 

 The recurrent nerve is reduced in size and gray in color, indicat- 

 ing degeneration. The posterior crieo-arytenoid, the lateral crico- 

 arytenoid and the transverse arytenoid muscles show pale yellow 

 streaks and degeneration of their fibres. 



Describe the appearance of the lungs in bronchopneumonia. 



This is a lobular affection, with scattered areas of consolidation. 

 These areas are not as firm as in croupous pneumonia. The cut 

 surface is grayish-red or grayish-yellow and not granular, but 



