152 



BEGINNINGS IN ANIMAL HUSBANDRY 







Fig. 81. The upper pic- 

 ture shows a sound hock 

 joint; the lower, one with a 

 spavin. Reproduced from 

 "Diseases of the Horse," 

 U. S. Dept. of Agriculture. 



discovered a method of operating by 

 which the roaring may be cured, and 

 what is known as the Williams' opera- 

 tion is now performed with success in 

 America and Europe. 



Spavin, also frequently called bone 

 spavin, is usually found at the lower 

 part of the hock joint, on the inside of 

 the leg. It is caused by a strain or 

 injury, and consists of an accumulation 

 of bony matter at the joint. This is 

 shown in a more or less thickening of 

 the part, as compared with the sound 

 hock. The occurrence of the spavin 

 is most easily seen by standing directly 

 back of the horse and viewing the parts 

 from the rear. The spavin causes lame- 

 ness and a stiff gait, and is regarded as 

 a serious unsoundness. It greatly dam- 

 ages the sale value and is more com- 

 mon on light than on heavy horses. 



Curb is also an unsoundness of the 

 hock. When sound, the back of the 

 hock, slightly below the point, has rather 

 a perpendicular or straight edge. If a 

 curb exists, there is a bulging or out- 

 ward curve a short distance below the 

 point, that may be seen by standing 

 opposite the hind leg. Hocks that do 

 not have curbs, yet that tend to round 

 out at this part of the leg, are said 

 to have a curby conformation. Curbs 



