THE aoKSE, ITS DISEASES. 439 



Sweeny has been placed among the diseases of the bones because it 

 sometimes proceeds from injury to the bones and joints. The difficulty 

 itself, however, is confined to the muscles. 



rv. Bone Spavin. 



The definition of bone spavin may be given as an inflammation, ulceF- 

 ation and bony deposit of the small flat bones in the lower and inner part 

 of the hock joint ; or of both the outer and inner ones, or from inflam- 

 mation of the cuniform and metatarsal bones, terminating in anchylosis 

 Ca bony union of the parts) rendering the jomt stiff. 



Foot, incapable of being raised from Natural poeition of the healthy foot when raisea 



groundby reason oi spavin. from the ground during ah easy trot. 



Causes. — Injury to the joint by concussion, sprains of the ligaments, 

 \he use of shoes with high heels or calks. Hereditary predisposition to 

 wpavin is common from weakness of the joints, bones and ligaments. 

 Consequently weak limbed horses or mares, or those with spavins, or 

 other diseases of the bones should never be bred from. 



Bone spavin is really one of the most formidable diseases with which 

 the horseman has to deal, and the attack is sometimes so slow and blind 

 that jockeys are often enabled to put off a spavined horse on the uuwarv, 

 the horse afterwards going dead lame. Nevertheless it will show itself 

 if the horse is allowed to cool, or is ridden into the water and allowed to 

 stand awhile, for a horse with spavin coming on as he becomes warmed 

 the ligaments become freer in their action, and an animal lame at first, 

 will go well enough afterwards ; yet, in the end the horse becomes jjer" 

 manently lame, until the deposit about the bone, called anchj'losia, 

 becomes solidified, when the joint is stiff and the lameness ceases. 



Causes. — The causes producing spavin may be various. Hereditary 

 *reakness of the limbs is undoubtedly one of the principal causes. Thus 

 a blow, a sprain, or any injury producing inflammation will cause spavin 

 in such, an animal, when in a strong muscled and fine boned animal it 



