DISEASES AFFECTING FEET 



to become lame at any moment. The conversion of the carti- 

 lages into bone is a gradually advancing process. Particles of 

 lime are first of all deposited, being subsequently replaced by 

 bony material. The change is one of degeneration, i.e., the 

 passage from a higher to a lower grade, with its attendant fall 

 of functional value (calcification). 



It may be asked, " Do side bones constitute unsoundness ? " 

 From a legal point of view they must of necessity do so. A 

 provisional statement is, however, necessary. Supposing that 

 the horse has a good sized foot, well open at the heels, and alto- 

 gether looks as though it could stand a bit of hard wear ; then, 

 if the animal is suitable in other respects, there need be no 

 hesitation in purchasing such a cart horse ; in fact, most 

 veterinary surgeons are in the habit of passing this class of 

 animal as sound under these circumstances. It is reasonable 

 to assume that there will be a reduction in the price. On the 

 other hand, never buy a light horse with side bone, or one for 

 heavy w^ork with a big, flat, or convex-soled foot. Narrow heels 

 must be avoided. 



Causes. — It is generally stated that side bones are here- 

 ditary, i.e., handed from ancestors ; consequently many horse 

 breeders are careful to avoid breeding from stock with the 

 side bone stigma attached to their names. Probably this 

 hereditary nature has been far over-estimated. There is no 

 doubt that it is faulty conformation which is the mainstay of 

 this predisposition (heredity). 



Upright fetlocks, small feet, and narrow heels are favour- 

 able towards the development of side bones. Concussion 

 transmitted, chrectly or indirectly, is the exciting cause. When 



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