Canker of the Foot 203 



Causes. — It may arise from an injury, as a prick, or the 

 irritation of a nail ; but at other times the cause is obscure. 



Symptoms. — There is an abundant, ill-smelling, colorless 

 discharge from the frog, which is large, spongy and covered 

 with fungous growths, and offensively smelling, cheese-like 

 masses. The very disagreeable smell is attributed to the 

 sulphm^etted hydrogen in the secretion of bone substance. 



Generally, there is a gross, heavy habit of body; hence, 

 canker is most frequent in cart horses, with thick, round 

 legs and large feet. 



Treatment. — Some veterinarians say that the treatment 

 of canker, by calomel (N^o. 214), is generally a successful 

 one. Others have not found it so, and recommend the 

 early removal of the whole horny sole of the foot, as the 

 only effectual remedy. This is performed as follows : — 



The animal having been properly thrown and secured, 

 make a groove at the immediate junction of the sole and 

 wall, all around the foot, commencing at the heel. Then 

 divide this circle into two halves by a groove, from the 

 cleft of the frog to the toe. Take a sharp scalpel and cut 

 cleanly through these grooves, into the sensitive j)arts, so as 

 to completely separate the sole from the w^all. Strip off 

 one-half of the sole first, then the other, removing every 

 trace of the horny covering of both sole and frog. Cut 

 aw^ay all fungous growths, and freshen up the whole with 

 nitrate of silver. Pack with dry tow, bandage, and put on 

 a leather boot. Apply a tourniquet, moderately tight, to 

 the fetlock. The dressing should not be removed for two 

 days, w^hen it may be done very carefully, after a thorough 

 soaking of the foot in warm water. 



If fungous gro^vths and the ill-smelling secretion still 

 continue, the surface must be repeatedly dressed with powers 



