.188 BOG SrAVIX. BOXE Sl'AYIX. 



the term ' curby,' they tend more to render a horse wortldess than abnost 

 any other defect to which he is Hable. 



Curb is also an hereditary complaint, and therefore a horse that has 

 once suffered from it should always be regarded \Wth suspicion, especially 

 if either of the parents has exhibited it. 



BOG SPAVIN. 



The hock is plentifully furnished with reservoirs of synovia to lubricate 

 the difi'erent portions of this complicated joint. Some of these are found 

 on the inside of the joint. From over-exertion of the joint they become 

 inflamed, and considerably enlarged. They are wind-galls of the hock. 

 The femoral vein passes over the inside of the hock, over some of these 

 enlarged synovial reservoirs, and is compressed between them and the 

 external integument — the course of the blood is partially arrested, and a 

 portion of the vein below the impediment, and between it and the next 

 valve, is distended, and causes the soft tumour on the inside of the hock, 

 called Blood Spavin. 



Bog spavin is a very troublesome disease, attended with no great, but 

 often permanent lameness, and too apt to return when the enlargement 

 has subsided under medical treatment. It must be considered as decided 

 unsoundness. In a horse for slow draught it is scarcely worth while even 

 to attack it. And in one destined to more rapid action, the probability of 

 a relapse should not be forgotten, when the chances of success and the 

 expenses of treatment are calculated. 



The cause of the disease — the enlarged synovial capsu.le — lies deep, 

 and is with difficulty operated upon. Unifoi'm pressure would sometimes 

 cause the absorption of the fluid contained in cysts or bags like these, 

 but in a joint of such extensive motion as the hock, it is difficult, or 

 almost impossible, to confine the pressure on the precise spot at which 

 it is required. Could it be made to bear on the enlarged- bag, it would 

 likewise press on the vein, and to a greater degree hinder the passage 

 of the blood, and increase the dilatation below the obstruction. The old 

 and absurd method of passing a ligature above and below the enlarged 

 portion of the vein, and then dissecting it out, is not in the advanced 

 stage of veterinary science practised by any surgeon who regards his 

 reputation ; it being merely the consequence, not the cause, of the disease. 

 The only method of relief which holds out any promise even of temporary 

 success, is exciting considerable inflammation on the skin, and thus 

 rousing the deeper-seated absorbents to carry away the fluid effiised in 

 the enlarged bag. For this purpose, blisters or firing may be tried ; 

 but in the majority of cases the disease will bid defiance to all appliances, 

 or will return and baffle our hopes when we had seemed to be accomjilish- 

 ing our object. 



A. horse with bog spavin will do for ordinaiy work. He may draw in 

 a cart, or trot fairly in a lighter carriage, with little detriment to his 

 utility ; but he will never do for hard or rapid work. 



BONE SPAVIN. 



A still more formidable disease ranks under the name of Spavin, and is 

 an afl^ection of the bones of the hock-joint. It has been stated that the 

 bones of the leg, the shank-bone, g, page 385, and the two small splint- 

 bones behind, //, support the lower layer of the bones of the hock. The 

 cube-bone, d, rests principally on the shank-bone, and in a slight degree 

 on the outer splint-bone. The middle wedge-bone, /, rests entirely ujoon 

 the shank -bone, and the smaller wedge-bone (not seen in the cut) presses 



