Soles softened by wet ground may be more prone to stone bruising and abscesses. Photo by Betsy Lynch.

The birds are singing, the weather is balmy, and you and your horse are delighted to be rid of the hard, frozen ground that even a perfectly sound horse can find uncomfortable underfoot. Spring may bring its own set of hoof challenges, though, and you need to be prepared for them so your horse doesn’t develop problems that could end up curtailing your riding time.

Warm temperatures, increased activity, and soft ground conditions that limit wear may mean that your horse’s feet will need more frequent attention at this time of year. Horses that may go eight weeks between trims in the winter may need a trim every four to six weeks in the spring to keep the feet well balanced. Maintaining a good trim schedule will keep feet at their healthiest, help prevent strain and lameness, and reduce the chances you’ll run into other spring-related problems.

Talk to your farrier about what objective measures you should use to decide when your horse needs a trim. For example, a common rule is to get a trim after no more than three-eighths to one-half inch of new growth. You can keep track of this a couple of ways. Measure the distance from coronary band to shoe (or ground) right after a trim, and start to re-measure weekly after about four weeks. Or, you can put a dot of nail polish on the top of the hoof wall, just under the coronary band, and keep track of how far it has grown down. Also, get attention ASAP if any of the following problems develop.

Lost Shoes
Spring means mud, and mud means lost shoes. Just about everyone runs into this annoying problem eventually. At best, it means lost riding time while you wait for your farrier to get to you (at his busiest time of year, of course). At worst, it can mean damage to the hoof wall.

When and where there is heavy mud, avoid turning your horses out. In addition to lost shoes, injuries from slipping, falling or twisting legs are also a risk. If the mud is unavoidable, the simplest solution is to leave your horse barefoot until ground conditions improve.

If shoes are going to stay on:

• Ask that nails be clinched rather that cut off flush with the hoof wall if the horse has strong, high-quality hooves. This gives the nails more grip. However, if walls are thin, weak or brittle, best to cut the nails off at hoof surface so a chunk of hoof wall isn’t torn off if the shoe is likely to get sucked off in the mud.

• Use side clips on the shoes for added security.

• Avoid pads if at all possible because pads decrease the security of the nail grip.

• Check shoes daily. If loose, get this fixed before putting the horse back out in the mud. If the shoe is properly secured to the foot, you shouldn’t be able to move it or see daylight between the shoe and the bottom of the foot.

• Shorten the interval between trims and resets. Friction in the nail holes makes them widen over time and loosens the grip.

It’s wise to keep a hoof boot or two on hand in the event of lost shoes. Hooves that have been trimmed for shoes do not have the rounded edges at ground surface that barefoot horses have. This makes them more prone to chipping and cracking. Shod horses also usually have thinner, flatter soles. It’s also common for some hoof damage to occur when shoes are lost. Having a boot on hand will allow you to protect the hoof and prevent further damage.

Frog Sloughing
Under winter’s hard, dry ground conditions, your horse’s frog may thicken up considerably, especially if he is barefoot and has naturally low heels. This is normal, similar to forming a callus, and helps to cushion the foot.

When spring arrives, the ground is softer and wetter, and hoof growth picks up. You may see large chunks—even the entire frog—fall off. This is called "frog sloughing." It’s a perfectly natural process and nothing that you need to do anything about. The horse may be a little tender for a day or two until the new tissues underneath can form a tougher outer layer. You can help this process along by painting on some Venice turpentine (available in most farrier or horse supply stores) or Tuf-Foot, www.tuffoot.com. If you’re going to ride, for your horse’s comfort it’s best to use a pair of boots until the frog toughens up.

Frog sloughing may also occur in shod horses. However, because the frog of a shod horse often has less stimulation, and most farriers routinely trim off the upper layers to some extent, it’s not as common.

Stay on Top of Foot Care • Hooves grow faster in spring, so trim more often. • Avoid muddy areas or leave your horse barefoot if mud is inevitable. • If your horse sloughs his frog, use boots while his feet are tender. • Thrush organisms look for dark, moist conditions, so keep your horse’s feet dry and clean. • A hoof sealant may help prevent hoof flaring, white line disease and abscesses.

Thrush
Wet ground conditions alone won’t cause thrush. However, if the organism that causes thrush becomes trapped in the hoof under a dense pack of moist mud, problems can develop. Thrush is usually caused by an anaerobic bacterium that thrives in dark, moist, low-oxygen conditions. It’s more common in stabled horses, but it can contaminate pastures as well. To minimize the risk of thrush:

• Trim the feet at frequent intervals, including trimming off excess frog that is sitting as a "flat" over the crevices beside the frog. A well-trimmed foot will self-clean more efficiently, while keeping the crevices open helps prevent build-up.

• Pick out your horse’s feet every day, paying particular attention to the frog crevices for any sign of the foul odor and dark, sticky material that is characteristic of thrush.

• Try to ensure that all horses have an area such as a well-drained run-in shed, where they can get out of wet, muddy conditions for part of the day so the feet have a chance to dry out.

If your horse does get thrush, the first step in treating it is a good trim that leaves the crevices beside the frog wide open while paring away any obviously infected tissue.

Thrush is highly sensitive to air and drying. Trimming and cleaning will cure most early cases. However, if the infection penetrates deep into the cracks of the hoof tissue, it may need to be treated with dilute bleach (about 50:50 bleach and water) or hydrogen peroxide, which can work as well as store-bought thrush treatments. Some commercial applications may be too harsh on the tissues.

For serious cases, another remedy is mastitis antibiotic cream, available in your local farm stores. These creams come in tubes with long, thin, flexible tips on the ends that can be used to inject the antibiotic directly into deep crevices. Pack the foot on top of this with clean cotton, or Hawthorn Sole Pack Hoof packing, www.hawthorn-products.com. The Sole Pack is nice because it is soothing, has antimicrobial properties, molds well to the foot, and forms a good barrier against moisture and organisms. Put the hoof in a boot or keep the horse confined to a clean, dry area until the problem is healed.

If an individual horse in a group seems more prone to thrush than the others, it may be because his feet are not being trimmed often enough and/or are contracted, which leads to deep crevices conducive to thrush, or the horse has a less than robust immune response. Trace mineral deficiencies, especially copper, may be involved. Discuss this with your veterinarian or a nutritionist.

Time For Shoes? If you were among the owners who decided to give your horse’s feet a break from shoes this winter, don’t be in too much of a rush to put them back on. If the ground is soft and comfortable for bare feet, and going shoeless doesn’t result in excessive hoof wear, it’s fine to postpone shoes even if you start riding again. However, with more rapid hoof growth and minimal wear, be sure to have his feet trimmed as often as needed.

Soft, Spreading Feet, Abscesses and White Line Disease
Although wet conditions get blamed for problems with feet spreading/flaring and white line problems, the truth is that a healthy hoof has a very high resistance to absorbing moisture. In some parts of the world, horses thrive in marshy conditions, such as the famous white horses of the Camargue in France. The catch here, of course, is "healthy."

Shod horses are more susceptible to moisture damage because the integrity of their hoof wall is breached by nail holes. With barefoot horses, excessive cosmetic filing along the hoof wall to make it look smooth removes the natural protective layer. Letting the feet go too long between trims, and/or failing to roll the edges of the hoof at ground surface, creates mechanical forces that favor the hoof wall flaring away from the sole during weight-bearing. The end result is excessive stretch on the white line, eventually weakening and tearing it. This leads to hoof flares, dropping soles, and an avenue of infection, which can result in either abscesses (aka "gravels") or white line infections.

The first step in both treatment and prevention is, again, good hoof care. Shod horses, especially those with thin or brittle feet, may benefit from a hoof sealant such as the SBS Equine products, www.sbsequine.com. Barefoot horses may also benefit from a hoof sealant. However, regular, correct trimming, including minimal rasping along the hoof wall and rounding the hoof at ground level, may be all that is needed to prevent problems. As with thrush prevention, it’s also wise to make sure horses have a dry, protected area where they can go to allow their hooves to dry out.

Don’t wait for problems to develop to take action. Shod horses won’t show much, if any, spreading of their hooves because of the shoes. But nail-hole widening and cracks around nail holes are early signs of water damage. If your horse is barefoot, learn what a tight, normal white line looks like and check the feet for any signs of widening. Don’t wait for the feet to spread, white lines to get severely stretched, and cracking to start before you get attention. Your farrier or vet can advise you as to whether a hoof sealant is in order. But even if you use one, don’t use it as a substitute for frequent hoof care.

When feet start to spread, it pulls on the white line attachments. It’s common for actual gaps to develop where the white line has crumbled and fallen out. If these only extend up inside the hoof for a short distance, a good trim, and rounding of the hoof edges, can usually remove those damaged areas and take care of the problem. However, if the separation of the hoof wall from the sole extends up inside the hoof further, there’s a chance you have white line disease.

Spring doesn’t have to be a problematic time for feet if you know what issues may arise, how to spot them, and how to minimize the risk. A healthy equine foot is resilient and resistant to most of these problems, so the most important step is to make sure your horse’s hoof care and diet are optimal during this time. Daily inspection of the feet and being alert for early signs of any problem will allow you to get correct treatment early, before anything serious develops.

White Line Disease
White line disease is an infection of the tissues in the junction between the sole and live foot structures with the hoof wall. It may involve fungal organisms, bacteria or both.

As with thrush, your best plan of attack is to keep the tissues dry and expose them to air. This is best accomplished by the farrier or vet removing the hoof wall in areas where there is no longer any connection to the foot. This exposes the organisms and prevents secondary complications such as cracking or traction on the healthy, sensitive tissues above the infected, separated area. When done carefully, so that the healthy tissue isn’t invaded, this causes the horse no pain whatsoever.

Once the infected tissue is exposed, your vet or farrier will recommend that a disinfectant be painted on for a day or two, after which the tissue will harden naturally and eventually grow out and be replaced by healthy, well-attached hoof again. Depending on how far up the hoof wall the infection extends, your vet or farrier may also recommend boots and some form of support for the bottom of the foot while it is healing. Trax pads, www.impactgel.com, put inside boots are a good way to accomplish this.

With relatively mild cases of white line disease, your vet may want to try an application of disinfectant combined with packing the hollowed out areas to keep them clean, and boots.

However, if you leave the damaged hoof wall in place, you will have to check carefully to make sure the infection isn’t continuing to spread up inside the hoof. You can do this by tapping on the hoof wall and listening for a hollow sound, or by gently inserting a thin, flat object (e.g., blade of straw, fingernail file) into the hollowed area and measuring how far up it can go.

Whichever method you choose, it’s a good idea to use a drop of nail polish to mark how far up the hollow pocket extends before you start treatment. Then recheck it every two to three days. If the hollowed out area is continuing to travel up inside the hoof, it’s time to have the damaged section of hoof removed so that treatment can be more effective.