328 BOVINE PATHOLOGY. 



readily takes place. The most frequent cause of laceration 

 is fracture of a rib with the extremities forced inwards. 

 ^' Tic '' under this name has been described '^ wind 

 sucking ^^ of the ox. It has been observed in France, 

 and is due to indigestion. 



The pleura of the ox differs from that of the horse, 

 mainly in the fact that the lower part of the posterior 

 mediastinum is as stout as any other part of the median 

 septum of the chest. Hence an accumulation of fluid may 

 take place in one pleural sac only, a state of affairs not 

 often seen in the horse. 



Pleueitis, Pleurisy. — Inflammation of the pleura 

 results from exposure, especially when east winds are 

 prevalent; it then assumes an enzootic, or even epizootic 

 character. It also occurs as a complication of pneumonia, 

 and a result of fractures of the ribs and other injuries. 

 It has been seen in a case of passage of a sharp agent from 

 the stomach, which gained exit from the body through the 

 thoracic walls. It is in some cases of a rheumatic character. 

 It may be circumscribed or diffused, unilateral or double. 



Symptoms.— Besides the general signs of fever, the 

 pulse is small, quick, frequent, and hard. The respirations 

 are peculiar, being principally abdominal ; the inspiratory 

 efforts being cautious, and the expirations prolonged. 

 The patient usually stands with an anxious expression. 

 A sharp, suppressed, painful cough is present. Pain is 

 manifested on pressure between the intercostal spaces by 

 the animal flinching and giving a grunt. Auscultation 

 detects the friction sound in addition to the ordinary 

 respiratory murmurs. A sudden subsidence of the acute- 

 ness of the symptoms denotes when effusion into the pleural 

 sac has taken place (Hydrothorax). Then the pulse 

 becomes soft, but is still frequent and small. The breath- 

 ing is laboured, with prolonged expiration, the thorax is 

 enlarged, for the ribs are separated from each other to the 

 greatest degree possible. Less pain is manifested on pres- 

 sure of the sides, and the animal feeds freely. There have 

 been noted a peculiar flapping of the notrils, protrusion of 

 the muzzle, and an anxious expression. Dropsical swellings 



