CANKER. 547 



up all parts with cotton packed in so as to keep out all dirt. If nec- 

 essary, this should be repeated in a few days. 



It is generally advisable to give some opening medicine, and 

 attend to the general health and exercise. 



^ Canker.. 



Canker of the foot is apt to supervene in cases of neglected or 

 badly treated thrush, quittor, or puncture, and often follows bad 

 cases of grease. It is most common in heavy draft-horses, that 

 are kept in damp, filthy stables, and is most prevalent about large 

 cities. 



Symptoms. — In this disease we find a morbid state of the sensi- 

 tive sole and. frog, and instead of sound, healthy horn, fungus 

 excrescences are thrown out, with an offen- 

 sive acrid discharge. When aggravated, the 

 whole becomes covered with a growth of fungi, 

 which are like shreds of leather in appearance, 

 with a great tendency to spread over or under- 

 run the sole, separating the horny from the sen- 

 sitive parts. It is very difficult to get the horn 

 to grow again. 



Treatment. — In no case is so much patience re- 

 quired as in canker, — in fact, it is generally con- 

 Showing Canker. ' sidered as incurable, from the difficulty experi- 

 enced in suppressing the fungus, and getting the 

 horn to grow again. , All loose and detached horn must be carefully re- 

 moved, so as to give free vent to the irritating matter. As much of 

 the fungus as may seem practicable, without much bleeding, should 

 be removed by the knife or cautery, and followed up by some 

 escharotic, such as acetate or sulphate of copper, nitrate of silver, 

 butter of antimony, or sulphuric acid. Whatever caustic is used, it 

 must be applied every day ;" for if neglected one day, it is apt to 

 underrun the sole, and may lose more than it will regain in a week. 

 Firm pressure is very beneficial, and should be constantly applied 

 by means of tow, firmly impacted, and retained by means of slips 

 of wood or hoop-iron slid under the shoe ; and the foot must be 

 kept perfectly dry. 



The caustic may be occasionally changed. To destroy the 

 fetor, chloride of zinc or chloride of lime may be dusted on, or even 

 occasional dressings of dry lime will be useful. With a dressing of 

 tar, in which verdigris and nitric acid, two drachms of each to one 

 pound, of tar, are well mixed, and applied with a degree of firm press- 

 ure, at least every second day, the worst cases can be cured. 



