The HoofArmor Trim Explained
Our goal is to have horses successfully travel completely barefooted…no horseshoes or boots of any kind. Because of the studies of the Mustang (from the Spanish “Mesteño” meaning “wild, having no master”) hooves in the U.S. we know that it is possible. Domestic and feral horses are not different species. Only their living conditions are different. As there were no horses in North America before 1492, having all been eaten, the only feral herds of horses that are here now came from many different sources. Although DNA testing has shown considerable Spanish horse genes in the herds, the mustang herds are comprised of a great variety of breeds such as drafts, Thoroughbreds, Quarter Horses, Morgans and ponies; gaited horses and even some Curly Horses.
Again, I will say as every horse is different, so every hoof is different. However, Mustang hoof studies have shown a distinct similarity, depending on terrain. As most of the mustangs are found in arid country because no one else wanted that land, their hooves reflect the ground surface: hard, tough, compact with a thick outer covering.
Feral horses, in wetter terrain, generally have or soon develop softer larger feet to better travel in that landscape. Also, due to lack of natural wear like their desert cousins, the wetland hooves are softer so they will break off before they become too long. I won’t be referring to the wetland horses for this trim, just the desert trim that is better for stone protection. However, the wetland example can be seen in many domestic horses due to pasture conditions.
What surprised me and others was that it is reported that in over 90% of the hooves studied, the hoof wall wasn’t touching the ground and the mustangs were walking completely on their soles and frogs. Although these structures were much thicker and tougher than domestic horses, the difference from the traditional way of regarding the hoof was the exact opposite from what I had been taught. This was a game changer for me. I changed my trim as I will describe, and rather than apply HoofArmor only to the bottoms of the hoof walls as a shoe would be, I applied it to the entire ground contacting surface; primarily to the sole.
I came to realize that the sole is what is affected by stone sensitivity, not the bottom of the hoof wall where we typically nail horseshoes. I realized then that sole thickness affects that sensitivity (think of the boots vs socks analogy) and recently I became aware that the sole callus affects that sensitivity, maybe more than the thickness.
It is virtually impossible to tell where the sole callus ends and the live sole remains. Many schools teach students to carve out that sole until they reach “live sole”. This removes the callus that gives stone protection and the toe callus that helps to support the coffin bone. The horse tries to grow callus and the farrier keeps removing it and people wonder why the horse is still sore over stones, or why it can’t transition from shoes.
I was honored one evening when Mike Savoldi told me that the trim I described to him simplified what he had been teaching in his lectures. Mike was the Master Farrier at the Kellogg Arabian Center at Cal Poly for 30 years. He dissected more hooves and did more disciplined hoof studies than anyone I know and traveled around the globe lecturing on the importance of Uniform Sole Thickness for healthy hooves. I told him my trim technique was to “lift the hoof and trim everything that stuck up above the sole”. And that’s pretty much it. What that does is level the sole and therefore the coffin bone to the ground, which is what Mike taught. Here’s a link or I can send you the pdf.:
Although that sounds simple, it was developed after reading and discussing other people’s research on mustangs and my own years of shoeing and barefoot trimming observations of horses in my care. Not very scientific, I suppose, to do something and watch how the horse likes it. Horses are very subjective, not objective, but it’s obvious when they are sore.
The other research I used was Dr. Bowker, head of the Equine Foot Laboratory of the College of Veterinary Medicine at the University of Michigan…
“Bowker’s research in these areas led to a wholly different theory of how the equine foot responds to ground impact. His research has focused on blood flow to and from the hoof, and the role it plays in energy dissipation. These study results led Bowker to believe that the modern-day horse should be trimmed so that more of the back part of the foot—including the frog—bears the initial ground impact forces and weight. His research demonstrated that if the foot was trimmed so that the frog rests on the ground, the back part of the foot would be stimulated to grow more fibrous and fibrocartilaginous tissue in the digital cushion, which appears to be protective of the more chronic foot problems.” Dr. Bowker also lectures against peripheral loading of the hoof…meaning horseshoes. Link…
The other goal I aim for in trimming is to have everything level across the back: both heels and both sides of the frog. An easy guide is that, if at all, the frog will lean toward the side that wants trimming. When the horse is standing on a level surface, the split between the heel bulbs should be perpendicular to the ground. The back half of the hoof is the heart of the foot and balance there is everything. This keeps the heel first landing even regardless of conformation.
The edges of the hoof wall on a HoofArmor trim are rolled just enough to not feel sharp edges that could chip. Mustangs have a bigger roll, but their hoof wall is also thicker. Replicating a mustang roll on most domestic horses exposes the laminae or white line as the leading edge when the hoof slides upon landing. As the laminae is the softest part of the hoof capsule this lends itself to gravels and tearing that can cause further infections. The quarters are the thinnest part of the hoof wall and are left as thick as possible. Heels should blend in with the curvature of the bars.
The bars are not designed to be weight bearing structures, but rather are supportive members that strengthen the hoof in the rear as it expands and contracts. Long bars can press on the internal tissues. Bars are trimmed so as to be passive and not bent over. In the case of desired expansion of contracted heels, the bars can be trimmed shorter to lessen their restriction on the expansion.
Another effect of this trim is that it will reflect the conformation of each individual hoof. Concerning hoof angles: I was taught to make the fronts 50 degrees and the backs 55 degrees. I soon gave that up when I saw horses being off in one foot from that trim. Now I let the hoof tell me what angle it should be and this trim will conform to that. I’ve noticed that horses with a more upright shoulder will have a more upright hoof and tend to wear the toes more, necessitating trimming the heels more. Horse with a shallower slope to their shoulders will have a shallower angle to the dorsal hoof and will grow more toe and be more susceptible to underrun heels. These are just observations over the years.
The HoofArmor trim will automatically compensate for base-wide or base-narrow horses by trimming the high side and getting the hoof back under the shoulder. This helps prevent flares and cracking from their opposite sides being out of adjustment.
The HoofArmor trim is more like Zen. You learn to read the hoof and let it tell you what it wants trimmed. You pick up a hoof with no preconceived idea of what you are going to do. The more these principles are followed, the more obvious the untrimmed hoof will look to you and the better the results will be for the horse.