322 THE PRACTICE OF VETERINARY MEDICINE. 



Sym^ytoms. — On an examination, the foot is found to be 

 hot and tender, the frog soft and spongy, and in a short 

 time the growth makes its appearance ; it is very vascular, 

 on being cut bleeds freely, and sometimes there is also a 

 discharge of a very fetid odour. The growth extends, 

 and may involve the whole of the sole and frog. The 

 animal is also more or less lame. The disease is charac- 

 terized by a tendency to spread, and ultimately, if not 

 checked, produces deformity of the whole hoof, with 

 more or less rapid degeneration of the whole horny 

 tissue. 



Treatment. — The treatment of canker is tedious, and not 

 always successful, it being in all cases difficult to cure. The 

 knife must be used freely ; the Avails are to be cut down, all 

 useless or semi-detached portions of horn being removed, 

 after which the hot iron may be used, but caustics in the 

 liquid form are better than the hot iron. Nitric acid is 

 probably the best caustic that can be used in the treatment 

 of canker, and should be used to cauterize the parts 

 thoroughly, after which, as a dressing, a pledget of tow 

 saturated with carbolic acid may be applied. Professor 

 AVilliams recommends chromic acid in the treatment 

 of canker, but it must be applied very carefully, as it 

 has a great affinity for water, and, uniting with the 

 moisture of the parts, may produce a flame. A favourite 

 recipe of Professor Dick's was the following : — Cupri 

 diacetate, 5ii. ; acid, sulphuric, 5ii- ; pix liquida, 5xvi., to be 

 applied as often as is considered necessary. It is good 

 practice to change the dressings occasionally. A well- 

 marked case of canker is very difficult to treat successfully, 

 and to cure requires, under favourable circumstances, a 

 })eriod varying from six Aveeks to tAvo months. After the 

 diseased condition is subdued by proper local treatment as 

 directed above, and constitutional remedies, as the ad- 



