40 DISEASES OF THE FOOT. 



Surgical treatment is the only reliable method in cases where hyper- 

 trophy of the papillary layer is well marked, and is extremely simple. 



The animal should be fixed in the trevis, the foot to be operated on 

 separately secured, and the growths completely removed with sharp 

 scissors or with a bistoury and forceps. When bleeding has subsided 

 the wound is covered with a mixture of equal parts of iodoform, tannin, 

 and pow'dered boric acid, and an interdigital dressing is applied. The 

 dressing is removed after five to ten days, according to circumstances. 

 If the cicatrix shows signs of exuberant growth it is dusted with 

 powdered burnt alum, and the parts are treated as an open wound. 

 When the growths are covered with horn and no longer painful it is 

 not desirable to interfere with them. 



CANKER. 



Canker — i.e., chronic suppurative inflammation of the podophyllous or 

 velvety tissue — is accompanied by hypertrophy of the papillae and pro- 

 gressive separation of the horn of the sole. It is much rarer in the ox 

 than in the horse, although it occasionally occurs. 



Prolonged retention in dirty stables, where the bedding is mixed with 

 manure and continually moistened with urine, ia the principal cause of 

 the disease. Individual predisposition and the action of some specific 

 organism may also have some influence. 



Canker in oxen, like the same disease in horses, is recognised by 

 softening and separation of the horn of the sole, and by progressive 

 extension of the process towards neighbouring parts. The usual course 

 consists in invasion of the podophyllous tissue, separation of the wall and 

 of the heels, and pathological hypertrophy of the horn-forming tissues, 

 producing condylomata. 



The new growths do not attain the same dimensions as in the horse, 

 but, on the other hand, the disease very frequently takes a progressive 

 course, invohdng the whole of the claw. A trifling accidental injury may 

 be followed by infection of the subungual tissues, and thus become the 

 point of origin for canker. 



Canker may attack only one claw ; on the other hand, it may extend 

 to both claws of one foot, or to the claws of more than one foot in the 

 same animal. 



Diagnosis. Diagnosis is easy. The separation of the horn, the 

 presence of a caseous, greyish-yellow and offensive discharge between 

 the separated parts and the horn-secreting tissues, the appearance of 

 the exposed living tissues, etc., leave no room for doubt. 



Prognosis. The prognosis is grave; for, as in the horse, the disease 

 is obstinate. 



