DISEASES OF THE HORSE. 473 



dry antiseptic dressing powder or carbolated vaseline ointment applied 

 to exclude the air. Granulation tissue (proud flesh) should be con- 

 trolled by the application of silver nitrate in the form of a caustic 

 psncil. 



Burns due to mineral acids may be first treated by flushing the 

 parts with a copious quantity of cold water or by the application of 

 whiting or chalk. Either use a large quantity of water at the start or 

 use the chalk first, then wash with water. If the irritant has been a 

 caustic alkali, such as potash, lye, ammonia, or soda, then vinegar 

 should be the first application. StahPs liniment is probably the best 

 general application for all burns for the first week; then this should 

 be followed by the ordinary antiseptic wound dressings. 



GANGRENE. 



Gangrene, or mortification, denotes the death of the affected part, 

 and is mostly found attacking soft tissue near the surface of the 

 body. Gangrenous areas may occur as a result of shutting off their 

 blood supply. Constitutional diseases, such as ergotism, anthrax, and 

 septicemia, predispose to gangrene. As external causes we have acids 

 and alkalies, freezing and burning, contusions and continuous pressure 

 that interrupt the circulation. There are two forms of gangrene — 

 dry and moist. Dry gangrene is most often seen in horses from con- 

 tinuous lying down (decubitus) or from uneven pressure of some por- 

 tion of the harness. 



Symjytoms. — There is a lack of sensation due to the death of nerves. 

 In dry gangrene the skin is leathery and harsh, while in moist gan- 

 grene the tissues are soft, wrinkled, and friable; the hair is dis- 

 turbed, and the skin is usually moist and soapy and sometimes covered 

 with blebs. The tissue surrounding the moist gangrenous patch is 

 usuall}^ inflamed, swollen, and hot, but this is less noticeable in the 

 case of divj gangrene. Moist gangrene often spreads and involves 

 deeper tissue, sheaths of tendons and joints producing septic sjnio- 

 vitis or septic arthritis leading to pyemia and death. Dry gangrene 

 is seldom dangerous, but the rapidity of its spread will indicate its 

 virulence. 



Treatment. — The preventive treatment consists in avoiding all the 

 influences that tend to disturb the nutrition of the tissues, such as 

 excessive cold or heat or continuous pressure. Gangrene following 

 decubitus ma}^ be prevented b}^ using soft bedding and frequently 

 turning the animal from one side to the other. In dry gangrene moist 

 heat in the form of poultices or anointing the tissue with oils and 

 fats will be found beneficial in hastening the dead tissue to slough off. 

 When the outer skin begins to suppurate, seize it with a pair of pincers 

 and draw it awa3^ After this treat the patch as an open wound. In 

 moist gangrene the tissue should be thoroughl}^ disinfected with creo- 



