DISEASES OP THE SKIN. 471 



become covered at the edges or throughout by firm incrustations re- 

 sulting from the drying of the liquids thrown out, and the skin be- 

 comes increasingly thick and rigid. A similar condition occurs 

 behind the knee and in front of the hock (malanders and salanders), 

 and may extend from these points to the hoof, virtually incasing that 

 side of the. limb in a permanent incrusting sheath. 



Causes. — Besides a heavy lymphatic constitution, which predisposes 

 to this affection, the causes are overfeeding on grain, unwholesome 

 fodder, close, hot, dirty stables, constant contact with dung and urine 

 and their emanations, working in deep, irritant mud; above all, in 

 limestone districts, irritation by dry limestones or sandy dust in dry 

 weather on dirt roads; also cold drafts, snow, and freezing mud, 

 washing the legs with caustic soap, wrapping the wet legs in thick 

 woolen bandages which soak the skin and render it sensitive when 

 exposed next day, clipping the heels, weak heart and circulation, 

 natural or supervening on overwork, imperfect nourishment, impure 

 air, lack of siinshine, chronic exhausting, or debilitating diseases, 

 or functional or structural diseases of the heart, liver, or kidneys. 

 These last induce dropsical swelling of the limbs (stocking), weaken 

 the parts, and induce cracking. Finally the cicatrix of a preexist- 

 ing crack, weak, rigid, and unyielding, is liable to reopen under any 

 severe exertion ; hence rapid paces and heavy draft are active causes. 



Treatment. — In treatment the first step is to ascertain and remove 

 the cause whenever possible. If there is much local heat and inflam- 

 mation, a laxative (5 drams aloes or 1 pound Glauber's salt) may be 

 given, and for the pampered animal the grain should be reduced or 

 replaced altogether by bran mashes, flaxseed, and other laxative, non- 

 stimulating feed. In the debilitated, on the other hand, nutritious 

 food and bitter tonics may be given, and even a course of arsenic 

 (5 grains arsenic with 1 dram bicarbonate of soda daily). When the 

 legs swell, exercise on dry roads, hand rubbing, and evenly applied 

 bandages are good, and mild astringents, like extract of witch-hazel, 

 may be applied and the part subsequently rubbed dry and bandaged. 

 If there is much heat but unbroken skin, a lotion of 2 drams sugar 

 of lead to 1 quart of water may be applied on a thin bandage, cov- 

 ered in cold weather with a dry one. The same may be used after 

 the cracks appear, or a solution of sulphurous acid 1 part, glycerin 

 1 part, and water 1 part, applied on cotton and well covered by a 

 bandage. In case these should prove unsuitable to the particular 

 case, the part may be smeared with vaseline 1 ounce, sugar of lead 1 

 dram, and carbolic acid 10 drops. 



