Hard soles are important to your horse’s overall hoof health. Thin soles, those less than 3/8-inch thick, in particular need additional hardness protection. If you can flex your horse’s soles with your thumb, they are soft. Your horse’s soles may never be hard enough to walk comfortably on rocky ground without protection, but they should harden enough to protect the critical structures, such as the coffin bone, inside her hooves.
Your horse will be far more sensitive and “ouchy” on hard ground than on soft ground until she develops callouses to harden the sole. These develop slowly, from several months to a year. You can slip boots over your horse's hooves to keep her comfortable while still allowing callouses to form. She will become acclimated to whatever ground she’s turned out on -- If her normal terrain is hard, her soles will get hard.
Soft, wet and muddy conditions work against hardening your horse’s soles. This means that if your horse spends a great deal of time in a stall, or her pasture is bogged down in mud and standing water, her soles will remain soft and unhealthy. She needs plenty of turnout, and a place to go to get out of long-term wet and muddy conditions.
Nutrition and Supplements
What you feed your horse influences the hardness and health of her soles. As with humans, proper nutrition is important, so make sure she is getting a good balance of forage and grain in an amount appropriate for her size and conditioning program. The addition of biotin, a common ingredient in hoof supplements, also can help harden her soles. Feed at least 20 mg. per day. Other nutrients to look for in a supplement are iodine, methionine and zinc. Supplements can take a good six months to work, so be patient. Adding extra fat to your horse’s diet also can help hoof health.
Venice turpentine is a popular ingredient that horse owners and farriers use to help harden soles. Other popular topical products include tea tree oil, iodine and pine tar. Some commercial products fight fungal and bacterial infections while they toughen up the soles; Keratex and Durasole are two popular brand name products.
- American Farriers Journal: Dealing with Thin-Soled Horses
- Rutgers New Jersey Agricultural Experiment Station, Equine Science Center: Nutrition
- Horse Journal: Keratex Will Definitely Harden Hooves
- Gene Fletcher Professional Farrier: Soft Soles
- Barefoot Hoof Care: Frequently Asked Questions
- CSM Hoofcare: Durasole
Based in Central Texas, Karen S. Johnson is a marketing professional with more than 30 years' experience and specializes in business and equestrian topics. Her articles have appeared in several trade and business publications such as the Houston Chronicle. Johnson also co-authored a series of communications publications for the U.S. Agency for International Development. She holds a Bachelor of Science in speech from UT-Austin.