Best Shod Horse - What is the judge looking for?
Best shod horse competitions are not won by some special type of shoeing just meant for show classes. They are in fact won by good forging skills needed in shoe making or shaping the shoes, allied to knowledge of equine anatomy and physiology, an understanding of the mechanical forces that act upon the legs and feet of a horse.
The basis of any good horse shoeing job is the hoof trimming and preparation. No horse has perfect limb conformation. It is not possible to just rasp a flat plane on the ground surface of the hoof at ninety degrees to the leg, not even a static leg. A horses limb is dynamic at all times the horse is standing, slight weight changes (a movement of the head) cause flexing of the hoof at different places around the wall.
Blood is kept moving through the foot, slowly perhaps, while the horse is at rest, and much more quickly at the faster paces. Researchers have measured a massive negative pressure in the digital cushion above the frog in a horse at trot, as the foot expands at the heels and the Pedal bone levers down from the toe under load from above blood must be drawn to such a low pressure area and displace blood ahead of it when the load is removed (the hoof lifting of the ground).
If one heel is left longer or the other rasped too much they will not work as a pair. The longer side hits the ground first and is shunted up while the shorter side is pushed down to reach the ground, with one half pushed up and the other pushed down, a sheer force is created that passes through the centre line of the frog causing the frog cleft to split deeply into the sensitive tissue. Often the condition exists in a pair of feet so the discomfort and pain can go unnoticed. Many cases of thrush which don't respond to normal treatment are caused by this constant sheering between the heels. The horses foot is a very vascular structure, the sole the frog and the sensitive lamina behind the horny wall and not forgetting the coronary band, it's this band of blood rich tissue that secrete the horny wall.
The coronary band is where the farrier first looks for some of the information that helps him balance stresses through the hoof. The coronary band with the nail bed on the underside produces horn tubules that should drop down like a curtain from a rail. Is the rail level? Any upward thrusting curve could indicate the hoof wall is to long in the quarters or heel. Some times this uneven nail bed cannot be changed as it is how the horse is made, but sometimes it is the hoof trimming that is at fault. Unshod horses on abrasive ground have a chance to balance out their own feet but shod feet mean the error remains and blood flow may be impaired or soft tissue damaged over and over with each foot fall.
If this scenario continues for months or years then the working life of that horse is maybe five to fifteen years shorter than it otherwise might have been.
The fit of the shoe is important as well. It should help break over, this reduces strain on the flexor tendons at the back of the leg as well as keeping lever forces in the front of the hoof to a minimum. The heels and sole also suffer less stress. The forces that produce quarter cracks in the wall are reduced if break over is easier. Any asymmetry beyond normal should be compensated for fitting the shoe a little wide at that narrow side when measured from a mid line down the centre of the frog.
Under load from each foot fall the bulbs of the heels sink down expanding the ground surface of the wall so any shoe fitted must allow for this expansion by being fitted wide enough to prevent the wall sliding off the shoe and over its edge. After only a week or so the shoe would sit inside the wall causing a loss of normal limb action and possible lameness if the heel and quarters of the shoe are not fitted properly.
The shoe should be long enough to reach the last ground bearing point of the frog.
In a good foot the last ground bearing point of the hoof wall at the heel would be level with the last bearing point of the frog, but often it isn't. The shoe should be wide enough to cover the wall and part of the sole, and long enough to provide support and cover for the heels. The ease of break over coupled to adequate length and cover of the heels is often enough to subtly move weight forward in the foot, placing it more centrally under the leg and closer to the pivot point of the Pedal joint.
Good logical foot preparation and sensible shoes fitted properly not only allow for improved action, reducing over reaching and pulled shoes, but the horse's useful life will be considerably lengthened.
Besides looking for all of these things, a judge of a best shod foot class will also be looking for craftsmanship in the work done. Good clean forge work on the shoes. Careless or unskilled, inaccurate hammer blows leave unsightly marks on the metal, in the trade it's known as "leaving your name and address".
The nails should be driven to a good height to have a firm hold on good horn, but not so high as to leave only the weak point of the nail to form a clench with. Equally nails should not be driven so low down that they are in the oldest weakest horn at the bottom of the hoof.
If the contours of the wall allow, it's nice to see all the clenches in a straight line, and not one up one down. Ugly deep grooves under the clenches show a lack of care taken, but also weaken the hoof wall at a vital spot.
Tim Challoner A.F.C.L.