PLEURISY 597 



the symptoms. Early in the disease the membrane is inflamed and 

 congested. At this time it is bright red in appearance and rough 

 on its surface. The rubbing together of the two layers of this 

 roughened organ is what produces the grating sound above referred 

 to. A little later on fluid passes out from these engorged blood- 

 vessels and separates the two inflamed pleural surfaces. This is 

 what causes the disappearance of the friction sound and the 

 increased difficulty in breathing. Later on, this fluid is again 

 absorbed and the inflamed surfaces again come in contact. This is 

 the time when the friction sound is again heard. 



In some of the chronic cases fibrous bands form between the two 

 layers of the pleura and cause permanent interference with breath- 

 ing. 



Course. — The course of the acute form of pleurisy is one to two 

 weeks. In the chronic form of the disease the course may be quite 

 long-drawn-out and last several weeks or months. 



Prognosis. — The outlook in pleurisy is not very good. A large 

 number of cases die. However, I am convinced, by the frequency 

 with which healed pleurisy is met with on postmortem in the large 

 packing houses, that many cases of this disease pass unnoticed by 

 the owner and recover. With proper treatment the prognosis in 

 this disease should be fairly good. 



Treatment. — As in pneumonia and other diseases of the respira- 

 tory tract, the preventive treatment in this disease consists largely 

 in the providing of proper quarters for the herd during winter 

 weather and protecting them from drafts and exposure. The 

 importance of preventing overcrowding and overheating has al- 

 ready been emphasized many times, and is equally important in 

 connection with pneumonia as in other diseases of the respiratory 

 tract. 



In the case of the sick animal it is important that it be placed 

 in comfortable surroundings and protected from drafts and ex- 

 posure. A good, clean, warm box-stall makes about the best ob- 

 tainable quarters. Plenty of bedding should be provided, and the 

 animal can be further protected by a blanket, as in the case of 

 pneumonia. Hot applications of various sorts may be made to the 

 chest wall to promote comfort. 



In the way of internal medication it is well to start with a purge 



