INFECTIOUS DISEASES I43 



wound on the lining membrane, or the inflam- 

 mation and irritation to the part caused by the 

 eruption of the teeth. Age is an important pre- 

 disposing factor, as the disease is ttsually seen 

 in pigs under two months of age. 



Symptoms. — At the beginning of the disease, 

 pigs that are nursing the mother are careless of 

 the teat and may refuse to nurse. Older animals 

 show a falling off in the appetite and eat sparingly. 

 The animal is feverish and acts dull. On ex- 

 amining the mouth at this time, the lining mem- 

 brane shows several inflamed patches, usually on 

 the gum and lips. In the early stages the inflamed 

 parts are a deep red color and swollen. Some- 

 times the snout and lips are badly swollen and 

 the breathing is interfered vvrith. Later the in- 

 flamed patches become necrotic and ulcers form. 

 In this stage the part becomes whitish or yellow- 

 ish white in color toward the central part of the 

 area, and inflamed and thickened at the margins. 

 The necrotic tissue soon sloughs off and deep, cav- 

 ernous depressions or ulcers form. These may in- 

 volve several of the teeth, or a large portion of the 

 lips and snout. The opening of the mouth causes 

 the animal a great deal of pain and the breath has' 

 a disagreeable odor. Salivation is sometimes 

 noticed. 



As the pig is weak, feverish and rjiable to 

 suckle, it soon becomes greatly emaciated. It is 

 usually seen standing or lying down in the pen, 

 or in some quiet place. It moves about but little 



