TRIMMING AND SHOEING SIX REASONS FOR POOR HOOF QUALITY Figure 1a Equine vet Scott Morrison examines causes of compromised horn
By Jeff Cota, Managing Editor Rather, it was a mechanical issue. “We pulled her toes back and used he mare’s feet didn’t look good. a roller motion shoe for a couple of They had a dull appearance, cycles before letting her go barefoot,” T were running forward and dishy. Morrison says. “Look at the hoof The hoof wall had chips and cracks, wall (Figure 1b). It’s like a different including one that traveled from the horse.” second nail to the coronary band Besides nutrition and mechanical (Figure 1a). issues, there are also four other possi- Figure 1b When poor hoof wall quality is ble explanations for poor quality horn evident in a horse, one of the first con- — genetics, hydration, coronary band siderations is whether its diet is well pathology and chemical damage. balanced. Convinced that more sup- plements were necessary, the mare’s Genetics And owner was no exception. While nutri- Mechanical/Shoeing tion certainly can be a culprit, there There are a number of factors under are other potential causes to consider. the umbrella of mechanical/shoeing “We’re all frequently asked that can influence hoof quality, includ- about hoof wall quality,” says Scott ing too much time between trimmings Morrison, a farrier and equine vet- and substandard farriery. erinarian at Rood & Riddle Equine “Poor, shallow nailing that splits Hospital in Lexington, Ky. “Not every the hoof wall can create some horse needs more supplements. A lot mechanical damage (Figures 2a of hoof wall quality problems are and 2b),” Morrison says. “Horses Figure 2a multifactorial.” that aren’t pulled back enough get In the mare’s case, an unbalanced long — especially weak, thin-walled diet wasn’t the source of the problem. Thoroughbreds. When the toes get FARRIER TAKEAWAYS `` Hoof wall quality problems are multifactorial and can be the result of genetics, mechanical/shoeing problems, hydration, nutrition, coronary band pathology and chemical damage. `` Horses with thin soles usually have poor quality hoof wall. `` Compromised coronary bands will generate poorly developed hoof walls. Figure 2b
52 American Farriers Journal | September/October 2017 Figure 3a Figure 3b
Figure 4a Figure 4b Figure 4c long, the soles get real thin.” “Trim the heels back to establish sole support increases sole depth sig- Blunting the toe shape, trimming a proper base of support,” Morrison nificantly, Morrison says. heels back and rounding the walls with says. “Toe shape is important. A more “The roller motion shoe is rockered a proper bevel are all ways to build a blunt shape creates a strong structure; slightly in the heel and toe,” he says. solid foot with your trim, he says. “More specifically, the last 1 inch “On the other hand,” Morrison of heel is rockered slightly. This says, “excessively trimming or corresponds to where the palmar cupping the sole and leaving sharp If the coronary band process of the pedal bone ends. edges are ways to destroy a foot.” The toe is rockered slightly from Horses that have thin soles is irritated, you’re the point directly beneath the usually also have poor quality front, or anterior, of the coronary hoof wall. going to have a hoof band.” “They get a really dull, For this mare, glue on shoes unhealthy looking wall wall that suffers … were used a few times and then (Figure 3a),” says the International left barefoot. Equine Veterinarian Hall Of Fame however, over squaring or over dress- “You can see how her hoof wall member. “But if you come up with ing the toe will weaken the hoof. It’s quality improved after probably 8 mechanics on how to build a healthier more of a 45-degree trim of the toe months of shoeing,” he says. foot and thicker sole, a lot of times you when pulling it back and bluntening improve the sole depth and their wall the toe shape. I rarely trim higher than Hydration Changes quality will come around quite a bit ½-inch up the wall when pulling the Unhealthy hoof wall that is suscep- (Figure 3b).” toe back. That leaves the bulk of the tible to hydration changes will exhibit Utilizing shoeing mechanics to build hoof wall toe bridge intact.” vertical cracks that start at the ground sole depth starts with the trim. Utilizing a roller motion shoe and surface and work their way toward the
AmericanFarriers.com 53 Figure 5 Figure 6 Figure 7
Figure 8 Figure 9a Figure 9b
coronary band (Figure 4a). These are After a year of painting with the Yet, there can be too much of a good referred to as weather or sand cracks. pine tar-based dressing, the hoof wall thing. Selenium is one such mineral. “Typically, these horses respond to has dramatically improved. “Horses need a little bit of sele- a hoof dressing,” Morrison says. “We “There are no cracks; beautiful feet nium, but it’s bad when you give them just use a pine tar-based hoof dress- (Figure 4c),” Morrison says. “It has a lot,” Morrison says. “It interferes ing to help protect the hoof from the the same diet, same farm, same farrier. with the disulfide bonds that help weather changes and give it a layer We just started painting this horse’s hold the protein structures of the (Figure 4b). ” feet with the dressing.” hoof wall together. When you feed Although Morrison uses hoof dress- Equally important was how they too much selenium, it replaces the ing, he cautions against sealants in were trimmed. sulfur and horizontal cracks develop these cases. “We rolled up the edges real well (Figure 5). Horses with selenium tox- “I think it just traps things in,” he and didn’t let the feet get splayed out,” icity can get really sore and can get says. “You want things that let the he says. “We kept everything tidy and severe founder.” horse’s foot regulate its own moisture rounded up. Those walls responded content. Pine tar-based dressings have really well.” Coronary Band Pathology a lot of natural antifungal and anti- Examining the health of the cor- bacterial properties in them. They’re Too Much Of A Good Thing onary band is critical for hoof wall natural and feet usually do fairly well Make no mistake, a well-balanced development. in them.” diet is critical for healthy hoof walls. “If the coronary band is irritated,
54 American Farriers Journal | September/October 2017 Figure 10 Figure 11a Figure 11b
you’re going to have a hoof wall that (Figures 9a and 9b),” Morrison says. that the horse is living in,” Morrison suffers,” he says. “That’s were the hoof “Maybe some of these cases start off says, “to see if there’s anything it’s wall is generated.” as a mechanical cause and then their allergic to.” Among the signs of a compromised immune system overreacts to it and the For example, a horse that merely coronary band is coronitis, which horse gets coronitis.” stands on black walnut sawdust is sus- is swelling of the coronary band Despite the uncertainty surrounding ceptible to laminitis and/or founder. and causes the hairline to stick up the cause, the treatment is clear. If a horse experiences an allergic (Figure 6). “Usually we’ll treat these cases reac tion, Morrison suggests: “I’m sure we’ve seen old retired hunt- with a steroid cream — betametha- ``Changing the bedding. ers or jumpers that have some coronary sone (Figure 10),” he says. “In some ``Check the hoof dressings. bands that look questionable,” Morrison cases, it works beautifully (Figures ``Check weeds in the fields. says. “Hoof wall that’s produced from 11a and 11b).” ``Perhaps a change of pasture. a coronary band with coronitis has Although there’s a possibility that a a scaly texture. It looks like a slate Chemical Damage horse is experiencing poor hoof qual- roof. It’s cracked, not very smooth and There are a number of environmen- ity because of an unbalanced diet, healthy looking (Figure 7).” tal influences that can adversely affect it’s important to examine all of the Coronitis often can be seen in the hoof wall quality. potential causes to avoid unintended heel bulbs (Figure 8). “You want to look at the environment consequences. “A lot of times it starts there,” he says, “and then creeps around to the front.” IMPORTANT VITAMINS, MINERALS AND PROTEINS It’s not entirely understood how The equine hoof needs a variety of vitamins, minerals and protein to grow or why coronitis occurs, but it can quality hoof wall. Here’s a look at how some affect the hoof. be brought on by such maladies as Vitamins pemphigus, an autoimmune disease; Vitamin A: A deficiency causes fragile wall and tubules don’t adhere sunlight hypersensitivity and liver dis- together. ease, among others. Biotin: This B vitamin increases tensile strength, hardness and growth rate. “I’ve biopsied lots of these and I It also decreases the incidence of wall defects. never really get a specific diagnosis,” Morrison says. Minerals “It usually comes back as an idio- Zinc: Low zinc levels have shown to cause weak, poor quality horn and pathic coronitis, which basically increased incidence of white line disease. means we don’t know.” Calcium: A deficiency results in brittle feet with poor tubular structure. After years of working with horses, Selenium: Excess selenium creates separations and horizontal cracks. he has a theory about one potential Protein cause. Disulfide bonds: These bonds in protein hold polypeptide chains to- “I think a lot of these occur in gether, giving hoof its high tensile strength. horses that hit the ground real hard
AmericanFarriers.com 55 TRIMMING AND SHOEING
56 American Farriers Journal | September/October 2017