140 DISEASES OF HORSES AND CATTLE. 



best. There is a form of warts which appear sud- 

 denly on the lips and nose of young colts and 

 calves, and sometimes on older animals. These 

 are small, and the whole lip will be covered with 

 them. They sometimes occur on the inside of the 

 lip of the dog. They require no treatment, and 

 will often disappear as suddenly as they came. 



Emphysema (Air Under the Skin). — This is usu- 

 ally the result of a wound, where the skin is loosely 

 connected with the muscles, as behind the elbow 

 or lower part of the neck. There is a peculiar 

 crackling beneath the skin when the pressure is 

 brought to bear upon the part. In the majority of 

 cases it requires no interference, as it will soon 

 pass away. In bad cases the skin may be punc- 

 tured and gentle friction applied. \ 



Mange. — This is a contagious disease caused by 

 a parasite. 



Causation: Although it is undoubted that the 

 essential and immediate factor in the production 

 of mange in any form is the presence of the mange 

 mite, we may not shut our eyes to the teachings of 

 experience, in so far as that these tell us that all 

 debilitating and exhausting influences, as expo- 

 sure, fatigue, want of sufficient food, and fitting 

 stabling render animals more susceptible to the 

 attack and rapid development of the inducing 

 parasite, and of course materially influence the 

 progress and termination of the disease. , The in- 

 fluences of these agencies have been observed and 

 their extent determined by all observers, particu- 

 larly by those associated with large collections of 



