BORSBS, JACKS, JENNETS, AND MULES 215 



Occasionally there appears what is known as a pegged splint, 

 in which the growth extends across the back of the canon, 

 beneath the suspensory ligament. 



The lameness which results from splints is rather easily 

 recognized: (1) By locating the splint, noting the sensitive- 

 ness to pressure at this point. A peculiarity of the lameness 

 is that the horse walks nearly or quite sound, but trots very 

 lame, especially on hard ground. There is a natural tendency 

 to recover. Lameness from splints is rarely seen in aged 

 horses for this reason. (2) When the splint appears very 

 close to the knee, or in the pegged form, there is less prospect 

 of natural recovery, and with the latter form lameness is very 

 apt to be permanent, unless relieved by surgical means. 



Ringbone. This is characterized by enlargement of some 

 portion of the pastern bones. It may be in front, behind, 

 on either side, or extend entirely around this region. It 

 may be located near the crown of the hoof or very much 

 higher, thus dividing ringbone artificially into two classes, 

 high and low. 



Ringbones are very much more serious forms of unsound- 

 ness than splints, as they are more apt to be permanent 

 in effect, and even if the soreness is relieved, there is likely 

 to be a mechanical lameness because of a stiffened joint. 

 This unsoundness and the lameness resulting from it are very 

 easily detected. 



Sidebones. A sidebone indicates an abnormal condition 

 of the lateral cartilages, which are naturally elastic. Side- 

 bones are detected as bonelike structures which appear above 

 the crown of the hoof and just beneath the skin on either 

 side. They may cause lameness during the period of inflam- 

 mation and hardening. In some cases the lameness is 

 persistent. 



Spavin. The cause of lameness, recognized under the name 

 of bone spavin, is an abnormal condition of the tarsal bones 

 at the lower, inner, front portion of the hock. There is 

 usually an enlargement, varying from a very small growth, 

 commonly called a jack, to a very large growth, known as 

 bone spavin. 



There is another form of bone spavin in which there is a 



