POLL EVIL AND FISTULOUS WITHEKS. 351 



CUAPTEK 16. 

 TOLL EVIL AND FISTULOUS WITHERS. 



710. Pull Evil. Naturey seat, and causes. 711. Peculiarities arisiiuj 

 from the i>ositioii of the injury. 712. Treatment. 713. Fistulous 

 Withers. Nature, causes, and treatment. 



710. Nature, seat, and causes. 



Poll Evil, as its name imports, occurs on the top of the head, just 

 posterior to the cars. In its earliest stage it is simply a swelling, caused 

 usually by the i)rei>sure of the head collar, or sometimes hy an accidental 

 blow, such as that vrhich a horse may give himself, especially if frightened, 

 on entering or quitting a stable thi'ough a low doorway. 



If the cause, whether it be pressure or a blow, be continued or repeated, 

 inflammation will probably set in. As a result of the inflammatory 

 action, the wound or injury frequently suppurates, and after a time 

 abscesses will probably form. 



711. Peculiarities arisimj from th»' position of the injury. 



From the peculiar position of the injury, the matter has no depending 

 orilice ; and hence it generally happens that, unless artificial assistance 

 by free incision is given for the escape of the matter, it will burrow down- 

 wards among and under the ligaments which support the head. Among 

 these it is apt to form large and deep sinuses and fistulse. 



These sinuses often extend down to the bone. The offensive smell of 

 the matter contained in them will indicate this extension. If the matter 

 is suffered to remain long in contact w ith the bone, it will probably cause 

 caries in that tissue. 



712. Treatment. 



With moderate care and attention, no case of real poll evil ought ever 

 to occur. Timely removal of the exciting cause will always check and 

 prevent its development. 



When, however, the disease by neglect and long-continued recurrence of 

 the cause has been suffered to develop itself, the treatment consists in 

 laying the part open with the knife, so as to afford a depending orifice 

 for the matter. 



When the injury is deep seated, it is good practice to assLst the esca})e 

 of the matter by inserting a seton through the sinus, with a view of 

 affording it a depending orifice. The wound itself will require to be 

 treated with a solution of sulphate of zinc in order to excite the parts to 

 increased action, and thus promote the healing process. The best treat- 



