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it must be remembered that such wounds must necessarily pierce the 

 pleura. A fractured rib may involve the pleura. The inflammation 

 following such wounds may be circumscribed, that is, confined to a 

 small area surrounding the wound, or it may spread from the wound 

 and involve a large portion of the iDleura. The i^leura may be involved 

 secondarily when the heart or its membrane is the x>rim.ary seat of the 

 disease. It may occur in conjunction with bronchitis, influenza, and 

 other diseases. It is commonly seen in connection with rheumatism. 

 Diseased growths that interfere with the i^leura may induce j)leurisy, 

 but it is most frecjuently met with in connection with pneumonia, for 

 the reason given heretofore. Pleurisy will be described here as an 

 independent afCection, although it should be remembered that it is very 

 often associated with the foregoing diseases. 



When the animal is affected with pleurisy an ordinary observer 

 should have no diflBculty in detecting the disease, i)rovided the diag- 

 nostic sj-mptoms are studied beforehand. The very first stage is a 

 congested state of the blood vessels in the parts affected ; the surface 

 of the membrane becomes dry and roughened (this fact will be again 

 referred to when the sj'mi^toms are described). This dry condition is 

 followed, after a certain period, by an effusion of fluid, that is, more 

 fluid than usual is thrown off by the membrane when in a diseased 

 condition. This fluid accumulates in the space between the lungs and 

 the walls of the chest, constituting hj'dro-thorax, or dropsy of the 

 chest. This fluid may undergo certain changes ; in it float coagulated 

 masses called- fibrin. The surface of the lung may adhere to the 

 internal surface of the ribs. The quantity of exuded fluid varies to 

 a great extent. In some cases the chest contains an enormous amount, 

 and when it is not absorbed pus may be generated to a greater or less 

 extent. 



Symptoms. — When the disease exists as an independent affection it 

 is ushered in by a chill, but this is usually overlooked. About the 

 first thing noticed is the disinclination of the animal to move or turn 

 round. "When made to d6 so he grunts or groans with pain. He 

 stands stiff, the ribs are fixed, that is, the ribs move very little in the 

 act of breathing, but the abdomen works more than natural; both the 

 fore feet and elbows may be turned out; during the onset of the attack 

 the animal may be restless, and acts as if he had a slight colic ; he may 

 even lie down, but does not remain long down, for when he finds no 

 relief he soon gets up. After effusion begins these signs of restless- 

 ness disappear. If the observer looks for it, a furrow will be found 

 running along the lower part of the chest fi'om behind the elbow back 

 to the flank; this is due to the endeavor of the animal to keep the ribs 

 fixed in as near as possible an immovable j)osition. Every movement 

 of the chest causes excruciating x^ain, therefore the cough is peculiar; 

 it is short and suppressed, and comes as near being no cough as the 

 animal can make it in his desire to suppress it. The breathing is 



