DISEASES OF THE RESPIRATORY TRACT 



COLD IN THE HEAD— NASAL CATARRH 



Causes. — Exposure to cold, especially if the ani- 

 mal is in an overheated condition or the body wet 

 with snow and rain, is the most common cause of 

 a simple cold. Hogs kept in crowded pens, or al- 

 lowed to sleep around straw stacks and manure 

 heaps, are very apt to sufifer as a result of becom- 

 ing overheated and chilled, or from irritation to the 

 air passages by the noxious gases and dust formed 

 under such conditions. This is especially true dur- 

 ing the cold weather, when a large number of hogs 

 are allowed to sleep in the same quarters. 



Symptoms. — The hog acts dull and feverish, and" 

 the eyes appear red and watery. During the first 

 or dry stage of the inflammation, which lasts for a 

 short time, the animal sneezes frequently. This 

 may be followed by a thin, watery discharge from 

 both nostrils. Later the discharge may become 

 heavier and pus-like, and white or yellowish in 

 color. If this continues for some time, the mucous 

 membrane lining the nose is thickened and changed 

 in appearance, and may become ulcerated. 



Severe outbreaks of nasal catarrh are known as 

 malignant catarrh. The disease does not run a well- 

 defined course, and the inflammation may extend 



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