TYPES AND MARKET CLASSES OF LIVE STOCK 487 



congestion and inflammation. But it is the after-effects which 

 are of most interest to us here. The disease sometimes becomes 

 chronic, and this seriously affects the secretion of the horn. The 

 toe of the hoof turns up, the heels become longer than natural, 

 while the hoof near the coronet is circled with ridges like those 

 of a ram's horn. These ridges are wide apart at the heel, and 

 close together in front, and are due to periods of interference 

 with the growth of horn simultaneous with the inflammation 

 of the fleshy laminae. Because of the high heel and turned-up 

 toe, the leg knuckles at the fetlock joint. Usually, accom- 

 panying these defects, the sole is found to be thin, convex, and 

 weak, and will stand but little wear. Because of the convexity, 

 the diseased tissues bear unusual weight, and such animals are 

 generally incurable cripples. 



Grease. This is not an unsoundness, but is such a trou- 

 blesome and common complaint that brief mention is here 

 given. It is a skin disease appearing nearly always in the hind 

 cannons. Draft horses are more subject to it than light horses. 

 Some individuals are predisposed to it those with coarse skin 

 and coarse feather. Other horses have it as a form of parasitic 

 mange, denoted by a greasy condition of the skin, congestion 

 of the skin, erect hair, and offensive odor due to discharge from 

 the sores. There is a constant itching and the horse rubs the 

 part, producing thickening and wrinkling of the ^kin. Treat- 

 ment varies. Half an ounce of Fowler's solution of arsenic 

 night and morning in the feed, burning with hot iron, applying 

 hot linseed poultices, dressing with lead lotion, giving a mild 

 physic, decreasing amount of feed allowance all these furnish 

 good methods of treatment. 



Hip down. This is a fracture of the point of the hip, often 

 caused by the animal striking the part against the door post 

 of the stable. It causes a flatness and sometimes the broken 

 piece of bone may be felt. It is best detected by standing 

 squarely behind the animal and viewing it across the hips. It 

 constitutes a blemish. 



Navicular disease. Navicular disease is a chronic inflam- 

 mation involving the navicular bone, the navicular bursa, and 

 the flexor tendon of the foot. It is brought on by repeated 

 bruising. Light horses are affected much oftener than heavy 

 horses. The hind feet are seldom affected. It is practically 

 never found in mules. One-third of the weight falling on the 

 leg is sustained by the little bow-shaped navicular bone, and 



