POLL EVIL AND FISTULOUS W1THEKS. 351 



CHAPTER 46. 

 POLL EVIL AND FISTULOUS WITHERS. 



710. POLL EVIL. Nature, seat, and causes. 711. Peculiarities arising 

 from the position 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 ears. In its earliest stage it is simply a swelling, caused 

 usually by the pressure of the head collar, or sometimes by an accidental 

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

 on entering or quitting a stable through 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 arising from the position of the injury. 



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

 orifice ; 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 fistulae. 



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 with 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 assist the escape 

 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- 



