DISEASES OF THE FEET. 85 



Symptoms. — At first there is simply an increased moisture in the 

 cleft of the frog, accompanied by an offensive smell. After a time the 

 discharge is more profuse, then watery and highly offensive, changing 

 gradually to a thick, putrid matter, which rapidly destroys the horn 

 of the frog. 



Treatment. — Remove the cause; keep stalls clean and dry. Pare 

 away all lose portions of the horn, so as to expose the diseased parts; 

 clean thoroughly by washing with warm water; dry with oakum and 

 pack with powdered alum, calomel, or copper sulphate; if the dress- 

 ing will not remain in place use a leather boot. 



CANKER. 



Canker is a disease of the frog and sole, marked by an offensive- 

 smelling, cheesy discharge, by a softening and breaking down of the 

 horny frog and sole, and a spongy enlargement of the sensitive frog 

 and sole. When this disease follows an injury which has exposed 

 the soft structures of the foot, it soon causes a separation of the soft 

 and homy portions, presenting a very imhealthy appearance and dis- 

 charging a thin, watery fluid. 



Causes, — Canker is generally believed to be caused by a vegetable 

 parasite, the development of which is assisted by filthy stables or low, 

 wet ground. 



Treatment. — That part of the frog or sole that has been underrun 

 must be removed with the knife and the canker exposed; the un- 

 healthy growth is then touched with a red-hot iron, burning it off 

 level with the surrounding healthy structures, care being exercised 

 not to injure the sensitive portions of the foot. Next, wash clean, 

 then dry and apply the following powder: Equal parts of sulphate of 

 zinc, sulphate of iron, and sulphate of copper. Place over this a pad 

 of oakum, and over all a leather boot. This dressing must be changed 

 once a day (twice a day in bad cases) ; treatment is continued until 

 a healthy growth of horn covers the whole foot. The horse can now 

 be shod. Pack the foot with oakum and tar and cover with a leather 

 sole, which is held in place by the shoe. 



If it is desirable to change dressings on the shod foot, a more con- 

 venient appliance to keep them in place is made in the following man- 

 ner: Cut a piece of sheet zinc to cover about two-thirds of the sole 

 and frog, the outer edge of the piece fitting under the shoe; cut 

 another piece to cover the remaining third and wide enough to lap 

 over the first piece, the lap to run parallel to the cleft of the frog; 

 then cut a strip about 1 inch wide to act as a keeper; the ends of this 

 strip are pressed under the shoe, the strip passing across the foot from 

 quarter to quarter. 



