DISEASES OF THE RESPIRATORY TRACT 47 



The respiratory sounds become more or less 

 changed from the normal. The cough is at first 

 deep and dry, later more loose and moist. It rnay 

 be accompanied by a hemorrhage during the first 

 stage of the disease. . Other respiratory sounds are 

 revealed by placing the ear to the side of the chest 

 wall and listening to the sounds in the lungs (aus- 

 cultation). This cannot be practiced in fat or rest- 

 less hogs with satisfaction, as the chest walls are 

 so thick that the lung sounds are deadened, or the 

 noise made by the animal hides the respiratory 

 murmurs. 



In the very early stages of pneumonia a crepi- 

 tating or crackling sound can be heard in the dis- 

 eased parts and louder sounds than normal in the 

 healthy areas. Later, when the engorgment of the 

 lung tissue occurs and the air cells become filled by 

 the inflamamtory exudates, the respiratory sounds 

 are deadened. On returning to the normal, rattling 

 sounds occur. These symptoms help greatly in 

 determining the animal's condition and in watching 

 the progress of the disease. 



The chances for recovery depend on the extent 

 and acuteness of the inflammation. Careless hand- 

 ling, exercise, etc., lessen the chance for a favorable 

 termination in this disease, and good nursing helps 

 more in bringing about a recovery than the medic- 

 inal treatment. The prognosis is more unfavor- 

 able in fat than in lean hogs, as the inflammation is 

 usually more severe in the former. The course of 

 the disease is from one to three weeks, and it may 



