On Spavin. 219 



"WTien in chronic cases there is considerable deposit of 

 water around the joint, blisters, setons and firing will often 

 lessen it. But when the bony deposits are once formed, there 

 are no means at our command to remove them. As a blis- 

 tering liniment in chronic cases, we may use — 



No. 234. Mercurial ointment, 2 oz. 



Oil of cantharides, 4 drachms. 



Mix and use locally. 



The oil of cantharides, which is preferred by some veteri- 

 narians to other forms of Spanish flies, is made thus : — 



No. 235. Powdered flies, 1 oz. 



Olive oil, 8 oz. 



Digest in a water bath for three hours, and filter. 



It is an efficient stimulating liniment. 



BONE SPAVIN. 



Definition. — A bony growth on the inner and lower side 

 of the hock, arising from inflammation of the adjacent bones 

 (the cuneiform and metatarsal), terminating generally in a 

 bony union between two or more bones of the hock, and thus 

 creating a permanent unsoundness. 



Causes. — These are defined to be hereditary and constitu- 

 tional. All writers agree that bone spavin is transmitted from 

 sires and dams to colts. Local exciting causes are sprains of 

 the ligaments, and the use of shoes with high heels or calks. 

 Blows, it is believed by the best surgeons, do not cause 

 spavin, in spite of w^hat certain horse breeders have main- 

 tained to the contrary. 



Symptoms. — Spavins do not always cause lameness, but 

 it is almost impossible to say which ones are not liable to 

 develop it. As a rule, those in front of the hock are most 

 feared. The lameness is, as a rule, removable in young 

 horses, but incurable in those past their prime. Yet one 

 which has existed for a number of years without producing 



