CAUSES OF UNSOUNDNESS. 119 



for the detection of this, but veterinarians, in the 

 absence of lameness in other parts of the limb, 

 very often fly to this as the probable source of 

 mischief. The vein passing over the inner aspect 

 of the hock sometimes appears to be plainer than 

 it ought to be — varicose, as it were— ^and to this 

 condition the term blood-spavin is applied. It is 

 not a diseased condition under any circumstances. 

 Regarding the nature of bone-spavin, it is possibly 

 rheumatic in some cases, but hereditary predis- 

 position is beHeved to play its share in the pro- 

 duction of it. It is chiefly during the formative 

 stage that lameness is so marked, and, after all the 

 acute signs have subsided, the animal may become 

 free from lameness. The spavin represents nature's 

 attempt to consolidate the joint, but, in doing so, it 

 is necessary to cement some of the smaller bones 

 of the hock together, so that some freedom of move- 

 ment, between these bones, must be lost. Spavin 

 is much more detrimental to a horse required for 

 fast work, than one wanted only for slow work. 

 Horses have been frequently passed as sound, and 

 then the buyer, has — say, within three weeks of the 

 purchase — been informed that the animal has a 

 spavined hock, although sold either with a warranty, 

 or else passed as sound by a veterinary surgeon. 



