332 DISEASES OF CATTLE. 



Frostbite on any portion of the l)ody may be treated as recom- 

 mended in the article on diseases of the ears. 



EMPHYSEMA (AIR OR GAS UNDER THE SKIN). 



Emphysema of the skin is not a true disease of the skin, but it is 

 mentioned as a pathological condition. It is characterized by a 

 distention of the skin with air or gas contained in the snbcutaneons 

 areolar tissue. It may depend npon a septic condition of the blood, 

 as in anthrax or blackleg, or air may be forced under the skin about 

 the head, neck, and shoulders, as a result of rupture of the windpipe- 

 It occurs in the region of the chest and shoulders from penetrating 

 wounds of the chest and lung, and occasionally follows puncture of 

 the rumen when the escaping gas is retained under the skin. 



Symptoms. — The skin is enormously distended over a greater or 

 less portion of the bodj'^; thus any region of the body may lose its 

 natural contour and appear like a monstrosity. There is a peculiar 

 crackling beneath the skin when the hand is passed over it, and on 

 tapping it with the fingers a resonant, drumlike sound is elicited. 



Treattnent. — Puncture the distended skin with a clean, broad- 

 bladed knife and press the air out. Further treatment must be 

 directed with a view to the removal of the cause. 



