CHAPTER HI. 



PEET OP THE HOBSE AND THEIR DISEASES, CONTINUED. 



I. THKUSH. II. NAVICULAR DISEASE. III. CONTRACTION OF THE FOOT. IT. 



GRAVEL. V. CANKER. VI. CALKS. VII. FRACTURE OP THE BONE ©F 



THE FOOT. VIII. STONE BRUISES. IX. SIDE BONE. 



I. Thrush. 



Thrush is the name given to a disease of the frog. It is a rotting or 

 ulceration of the frog, and is attended with a very offensive, black, wat- 

 ery discharge. The frog rots completely off sometimes, and extends 

 down in the cleft between the heels, to a depth of from half an inch to 

 two inches. 



Causes. — Uncleanliness, standing in a filthy stable, especially in their 

 own excrement. The filth remaining in the foot a long time and exclud- 

 ing the air, sets up decay which runs into ulceration. 



How to know it. — The ragged frog, offensive smell, black discharge, 

 deep cleft between the heels, which causes them to drop in towards each 

 other, making them look very much contracted, are evident signs. In 

 bad cases the animal sometimes goes lame, but not in mild cases. Still, 

 great harm results from neglecting it, on account of the injury to the 

 shape of the foot. 



What to do. ^Trim off all the ragged parts of the frog, clean out all 

 the holes and crevices with a case knife, or some similar instrument, then 

 apply a linseed poultice, with charcoal powdered over the surface. After 

 twenty-four hours clean it all off, and dress the affected f)arts with calo- 

 mel well introduced into all the cracks, with the case knife. Repeat this 

 once or twice, letting a day intervene between the applications. When 

 it is all dried up, dress the part with pine tar. 



Prevention. — Pick out the feet well, each day, to let the air in around 

 the frog, which is necessary to keep them healthy. 



n. Navicular Disease. 



One of the tendons of the leg {the flexor pedis perforans) passes 

 down the back of the leg to the foot, and around beneath the navicular 

 bone and joint of the foot, that lies directly above the frog. The tendon, 

 passing between the bone and the frog, attaches itself to a rough hollow 

 on the sole of the coffin bone. Disease in that part of the tendon, bone 

 or joint is navicular disease- 



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