84 PRINCIPLES OP VETEBINAET SUEGEBT 



Describe tJie symptoms of dry gangrene. 



Since in this form the supply of arterial blood is gradu- 

 ally diminished, while the outflow of the venous blood is not 

 interfered with, the tissues, aided by evaporation, gradually 

 lose their water and mummify — that is, become hard and dry. 

 Thus the gangrenous skin appears black or brownish, is 

 hard and leathery, and feels cold and is painless, but little 

 decomposition occurring in this form. 



What regions of the body are mainly exposed to dry gangrenef 



The neck and back, from harness pressure ; in animals 

 which are in the recumbent position a great deal, the skin 

 over the external angle of the ilium, and about the eyes ; in 

 the dog, the tip of the tail ; in cattle, the claws. 



Describe the sym,ptoms of moist gangrene. 



"When the arterial blood supply or the return flow of 

 venous blood is suddenly stopped, the following symptoms— 

 that is, those of moist gangrene — are likely to be noticed: 

 Depending on the part involved and the extent of the lesion,, 

 there is intense inflammation, more or less impaired function, 

 lameness, etc. The affected tissues feel soapy and soft at 

 first and change finally into a pulpy, smeary mass, while 

 the natural color of the tissues is changed into either a yel- 

 lowish, greyish, blackish, brownish, or greenish hue. Thus, 

 for instance, the color of the lateral cartilage becomes dis- 

 tinctly green. The necrotic tissues are cold and insensitive, 

 an ichorous, foamy discharge being present, accompanied 

 by a decided stench, due to the presence of putrefaotiTO 

 bacteria, -especially noticed in gangrenous emphysema. 



What constitutional effects may gangrene have ? 



It may be followed by septic and pysemic infection. 



