HEREDITARY UNSOUNDNESS 13 



appear to be much better developed than the ex- 

 tensors, and in an individual so formed, particu- 

 larly if he is inclined to stand with his forefeet 

 well back under him, there is an inordinate strain 

 on the extensors, leading to relaxation and a cor- 

 responding tendency to contraction of the flexors. 

 Here we have a lack of balance between the ex- 

 tensors and flexors, and the result is a knee- 

 sprung condition. Although shaky-kneed or 

 knee-sprung horses are not frequently incapaci- 

 tated for work, the breeder should not lose sight 

 of the fact that this condition is apt to con- 

 siderably depreciate a horse's value in the market, 

 particularly for some purposes, and he can sel- 

 dom afford to ignore this fact. It is not intended 

 to advise breeders never to breed to a sire that 

 stands a little over in the knees, especially if suf- 

 ficient cause can be assigned for it, but we should 

 recommend them to be very wary about using 

 sires and dams that show a congenital tendency 

 to this defect. Purchasers of horses usually look 

 with considerable disfavor on a horse that is at 

 all knee-sprung. Personally, the writer would 

 rather buy a horse for his own use that is a little 

 forward in the knees than one that stands back 

 in them or is what is called calf-kneed. A horse 

 with the former defect is almost sure to be much 

 more elastic in his step than one with the latter 

 and, consequently, will not suffer to the same ex- 



