Diagnosis. 171 



sequently interfere with the proper movements of the lungs. 

 Most dangerous in this respect are adhesions at the lower pos- 

 terior thirds of the lungs, or the lower posterior margins. An- 

 imals with adhesions in these parts usually suffer for the rest 

 of their lives from shortness of breath, even if their general 

 state of nutrition is good. Adhesions of the lungs may also 

 bring it about that the portion which is fixed in an abnormal 

 place is unable to return to its normal place after the exudate 

 is absorbed. The neighboring portions must then expand more 

 extensively, the heart may be displaced toward the affected 

 side and the thoracic wall may eventually be depressed. 



Chronic pleurisy does not terminate in complete recovery, 

 particularly since the compressed pulmonary tissue becomes 

 permanently solid, on account of the collapse of the alveolar 

 walls, and on account of the connective tissue proliferation. 

 Such animals are easily tired out when worked, their nutrition 

 is not good, they cough periodically, breathe with difficulty and 

 the presence of an exudate in the lower portion of the thorax 

 can be demonstrated objectively. 



Chronic pleurisy sometimes develops as such from the start and 

 only reaches a high degree after months. According to Rigot and 

 Cruzel, this form is particularly common in cattle, and as Lafosse and 

 Trasbot state, particularly after milder, but fre(|iiently recurring, colds. 



A fatal termination of pleurisy occurs in acute cases usu- 

 ally after two to three weeks, in consequence of suffocation or 

 exhaustion. Before death the sick animals show great dyspnea, 

 the nostrils are convulsively dilated in each inspiratory act, 

 the ribs are extensively elevated with a simultaneous elevation 

 of the spinal column and the mucous meml)ranes are cyanotic. 

 The animals finally fall down, try several times to get up again, 

 kick around the floor and die in convulsions. Death sometimes 

 comes on quite unexpectedly with the symptoms of cardiac 

 weakness during an attack of suffocation. In some chronic cases 

 the animals succumb completely prostrated. 



Diagnosis. The only pathognomonic sign of pure fibrinous 

 pleuritis is the friction sound heard synchronously with the 

 respiratory movements. If, however, in the course of a dis- 

 ease which is usually followed by pleurisy, tenderness of the 

 intercostal spaces come on, one is justified in thinking of the 

 probability of a beginning pleurisy. Rheumatism of the inter- 

 costal spaces (pleurodynia) is very rare and can be distin- 

 guished from pleurisy, even in the absence of friction sounds, 

 on account of marked general disturbances which are present 

 in pleurisy, by the accelerated and weak pulse, acceleration of 

 the superficial, so-to-say trembling, respiratory movements. 

 Affections of the ril)s (fracture, periostitis, caries) are charac- 

 terized ])y swelling and tenderness confined to the ribs, as well 

 as by the absence of general symptoms. 



