SYMPTOMS OF SPAVIN. 65 



its fluctuations — for the horse being so much lamer at some times 

 than at others. Secondarily, lameness may be produced, in chronic 

 inveterate spavin more particularly, by inability to flex and extend 

 the hock as usual, owing to some increase or alteration in the 

 joint oil, or else in consequence of partial anchylosis. Indeed, 

 lameness may vary in degree from what is called " stifl'ness" in 

 action to downright halting or hopping. In general, the lameness 

 bears no proportionate intensity to the magnitude of the spavin : 

 a horse may have a large exostosis on the spavin place, and yet 

 not evince lameness ; on the other hand, a horse may be extremely 

 lame, and yet only " a knot" be discoverable in the seat of spavin. 

 Ordinarily, the lameness arising from spavin not being such as to 

 incapacitate the horse, and being behind instead of before, he is 

 kept at work with it when he ought to be laid up. Most likely, he 

 goes quite limpingly when first he leaves his stable in the morning, 

 but, after having gone awhile and got warm, his lameness shews 

 itself less and less, until at last he goes all but or quite sound ; 

 the explanation of which appears to be, that any redundance or 

 incrassation of the synovial fluid the morbid condition of the hock 

 may have caused, is by action, by repeated flexion and extension, 

 temporarily removed ; and the motion which from that cause, or 

 from partial anchylosis, at first was stiff" and painful, becomes by 

 degrees comparatively facile and painless. In a case, however, 

 where there exists much inflammation of the tissues, or in that 

 form of disease in which ulceration or caries is present, exercise, so 

 far from benefitting the animal, makes his lameness worse. 



My own observation has led me to note two kinds of lameness in 

 spavin : — one, the effect either of the ordinary sub-acute or chronic 

 inflammation, or of partial anchylosis of the parts, is but com- 

 paratively slight, and consists, for the most part, in stiffness on 

 motion, or in defective flexile power of the hock joint; the other, 

 the effect of acute inflammation of the spavined parts, or else of 

 ulceration of the joints, consists in a sort of spasmodic catching-up 

 of the spavined limb the moment the heel of the foot comes down 

 upon the ground, something after the manner of stringhalt. Stifl'- 

 ness may not infrequently be observed even in the horse's side 

 movement in his stall. With such characteristic lameness as 



VOL. IV. K 



