In reference to spavin, it is a somewhat peculiar disease, inasmuch as its existence ranges from confirmed and incurable lameness, to being all but (sometimes, indeed) perfectly innocuous-this not depending on its nature or size, but on the part on which it comes. If it in no way interferes with the pliability of the joint, it is, in point of fact, mere exostosis on the hock-bone, that may probably remain there during the horse's life without causing him inconvenience, unless it does so during its growth, when it may produce inflammation of the external periosteum, as frequently does a splent on first appearing, from the same cause. A splent, if occurring directly below the knee, and thus interfering with the action of the joint, is virtually a spavin on the fore-leg, though called by another name; this, if only appearing, we will say, on the front of the cannon-bone, might remain there, ad infinitum, without injury. With spavins, one inch difference in the situation causes pro bably all the difference between a useful or comparatively useless horse.
It requires no common eye to detect the presence of spavin in some cases. For instance, a horse with very large and prominent bones to his hocks will often appear to the inexperienced to have spavins, whereas this very circumstance is a strong guarantee against his ever being so afflicted. Such a horse is, in stable phrase, "rough in or on his hocks." It is not my province to enter into strict pathological description of the origin or nature of complaints; I merely give, as I have been requested to do, such information as pretty long experience warrants. There is one hint I will give, which may help those not conversant with such matters in distinguishing between a horse with strong irregular projection on his hock, arising from naturally large bones, and the projection that is caused by incipient or confirmed spavin. In the first case the edges of the projecting bone will be found definite, decisive, and to a certain degree sharp. In the spavin these edges do not appear; but the projection is, as it were, rounded off.
The projection in the region of the part where usually spavin appears, whether natural or from disease, is usually best seen by looking at the hocks from between the fore legs; but the mistake between naturally large and diseased hocks may still be made. One criterion I have always found a correct one to go by, which is this.
Nature sometimes indulges in somewhat curious freaks in forming her creatures, quadruped or biped, and disease will sometimes so alter parts of form or feature as to render the one or the other scarcely recognisable; but she rarely afflicts two limbs in so precisely equal degree that there is not to be dis covered a difference between the appearance of the two. Thus, if the two hocks, in point of projection of bone, feel and appear strictly alike, however suspicious such enlargement might be (unless, indeed, the horse went lame, or showed stiffness), I should feel satisfied it was natural; but the slightest difference would at once quite alter my opinion. I have had no experience as regards spavined horses in my own case, having been fortunate enough never to have a horse throw out one-and I took especial care never to buy a horse with one, or, to the best of my judgment, with hocks likely to fail either from natural weakness or bad formation; but with the complaints "of horses belonging to others I have had a good deal to do-friends have always fancied I knew a good deal more than I really do; so I seldom had a spare stall, box, or outhouse, but it was converted into an hospital for friends' lame or sick horses. I can assure the reader I did not find playing gratuitous vet. a' very profitable occupation. I am not aware of there being any peculiar-shaped hock more liable to spavin than another, though there decidedly is so as regards curbs. It is a very singular fact, or at least I hold it to be such, that, however placed the hock of the horse may be, whether it inclines inward, or outwards, or whatever may be his action or mode of going, all ailments fall on the inside; now there are joints and integuments in play on the outside as well as the in, but I never saw or heard of a spavin on the outside.
There are three ways in which a horse's hocks are, as it is termed, "set. under him." What I should call the proper way is when the hock, and consequently the leg, stands straight, neither inclining right nor left; such horse will be usually found to set his leg firmly on the ground, and to support the weight of the body as on a firm, steady prop. Others have their hocks inclining inwards, - "pinned in on his hocks;" while again, others are to a certain degree, as it were, bandy-legged behind, forming, as a writer might term, a parenthesis ( ); such hocks, on coming to the ground will be usually, seen (to use a not very erudite term) to whabble about, but ending in twisting outwards-many to such a degree, that, on the foot being placed on the ground, that also twists out of its place in an outward direction. I cannot but hold either of the two last-mentioned peculiarities as at least failings.
I have seen many horses a little "tied in at the hocks," capital goers; but there is usually an unpleasant movement in horses with their hocks set wide apart, and I have remarked such to be liable to clack or "forge" in trotting-a very disagreeable habit, but one usually easily remedied. The outward twisting of the hocks and feet is particularly found to be produced when harness horses are going up hill with a heavy load behind them, such as we must now say formerly was the case with stage coaches. The greatest help we could afford such horses was by shoeing them particularly square at the toes on their hind feet; in fact, all horses for harness purposes should be, more or less, shod thus. The firm bearing it gives the toe on the ground will be at once perceived by taking a horseshoe and holding it on a table with the toe on the surface and the heel pressed on by the hand; it will be found the roundness of the toe gives it a mere point to rest on, consequently it twists from side to side. Now reverse the proceeding: let the two heels rest on the surface, the shoe will be found immovable. Shoeing round or square at the toes in a mitigated degree has the same effect, for it is the toe that in going up hill forms the principal appui.
It will be observed I have hitherto only alluded to bone spavin or exostosis of some sort. I have remarked the outside of the hock not being subject to similar complaint; even splent occurs ten times on the inside of the fore leg to once on its reverse. The only failing, or I should rather call it disfigurement, incidental to the outside of the hock, that I have observed (save from blows or other violent contact) are thorough-pins; these, as the name indicates, appear on each side; they are, when large, very unsightly, but seldom (I might figuratively say, never) lame; they are merely bursae-too soft in substance to lame by pressure on other parts; they are, in fact, swellings coming on each side of the limb above the hock, and by pressure may be caused, while the pressure lasts, to disappear on either side of the limb -the size being doubled, or nearly so, on the other. I once had a horse with very large thorough-pins; they were as large as half a good-sized apple on each side of the hind leg. I bought him from seeing him carry fourteen stone in a "clipper" with Lord Howth's hounds, and, further, seeing him take the Mardyke (a piece of water as well known in Ireland as the Whissendine is in Leicestershire) in his swing.
I considered if he could go as he did with fourteen stone on him, he would feel eleven as racing weight; he did so, and his thorough-pins were no detriment to him.
The next ailment in the region of the hocks is hood or bog spavin. These are very common, and numbers of horses have them, more or less unnoticed. They do not often lame, unless very large. I once bought a horse, knowing he had them. He was a trotter. He was not lame till, of a sudden, they enlarged frightfully. I put him in the hands of a vet., who promised me he would send him back in a week with no signs of spavin remaining. He kept his word, and the horse kept sound-that is, till I sold him, six months afterwards.
I believe I have now mentioned all or most of the ailments incident to the hock, with their probable consequences. I therefore take my leave of the subject.