SPAVIN 75 



impossible. A simple study of the bones, however, will reveal the fact 

 that the ridges are present, and they must necessarily affect the external 

 contour of the part, however slightly. It is not claimed that the grooves 

 are such as would readily accommodate a finger. If such were the case 

 there would be no art in detecting them ; but by educating the sense of 

 touch, and with a knowledge of the underlying osseous structures, a keen 

 observer should be able to differentiate between a levelling up of a 

 surface where normally there should be a slight depression, and still more 

 so should he be able when there is present on that surface, an elevation. 

 One has only to refer to the Sheather v. Simmons case for ample proof 

 that importance in diagnosis can be attached to the grooves (see 

 Plate XVI.), and these remarks particularly apply to the finer, thin- 

 skinned animals. 



Now spavin has for one of its characteristics an enlargement which 

 appears sooner or later on the area we have inapped out. The earliest 

 observers considered the enlargement to be of an osseous nature. There 

 were others who considered it as a thickening of the ligaments, but the 

 oldest view is now generally accepted ; but contention still wages round 

 the exact seat of origin of the affection, some maintaining that it 

 commences in the extra-osseous structures and extends to the bones, 

 whilst others contend that it commences as an inflammation of the 

 bones [i.e., an ostitis) and extends from them to the surrounding 

 structures. 



The late Professor Williams defined spavin as " an exostosis on the 

 inner and lower part of the hock, arising from inflammation of the 

 cuneiform and metatarsal bones, terminating generally in anchylosis of one 

 or more of the gliding joints of the hock." Moller and Dollar state (1903) 

 that "the view that the bone tissue is the primary seat of the disease 

 is old, but has again quite recently been advanced by Eberlein. Eberlein's 

 views are supported by the experiments of Gotti, and consist in regarding 

 the bone substance as being primarily attacked, after which the cartilage 

 of the joint, the periosteum, and the ligamentous apparatus are successively 



