It’s important to learn how to avoid abscesses and treat them when they occur.
By Kristin Pitzer
Many reiners have been there—you go to tack up and find your horse is dramatically three-legged lame. It appears he’s unable to put any weight on the offending leg, almost as if it’s broken. But in many cases, the cause of the pain is a small abscess in the hoof.
Abscesses can greatly hinder a horse’s training, and when they happen repeatedly or to multiple feet, they can make trying to ride even more frustrating. With a little help, a good horseman can diagnose an abscess, treat it, and learn how to avoid them in the future.
Abscesses 101
An abscess, which is an infection in a closed space, isn’t limited to your horse’s feet. In fact, one can happen anywhere in the body. According to Dr. William Rhoads of Premier Equine Veterinary Services in Whitesboro, Texas, abscesses are typically found wherever lymph nodes are located in the body—in the chest, abdomen, under the throat, and in the groin area. Strangles is a well-known bacterial infection that can cause abscessing at the lymph nodes, generally in the submandibular, or jaw, area. When a horse develops an abscess at a site other than under the jaw, it’s called bastard strangles.
Outside of lymph nodes, though, abscesses are most commonly seen in the feet, and it doesn’t take much to produce ideal conditions for one to develop.
“Most of the time, an abscess starts out as a bruise in the subsolar tissues and then gets infected and turns into an abscess,” Rhoads said. “Your horse can get a little puncture wound when he steps on something sharp or even a rock. The tissues in the foot are somewhat flexible, and sometimes they’ll allow things to puncture through. Then it seals that infection in there.”
Danny Anderson of Anderson Horse Shoeing in Collinsville, Texas, is a Certified Journeyman Farrier and the president of the Texas Professional Farriers Association. He typically sees abscesses more frequently during the wet times of the year, especially in horses that live out in the pasture versus in stalls, as they’re more susceptible to the elements.
“In extreme transitions, like in July and August when it goes from wet to really dry, or dry to really wet, you’ll see more, too,” Anderson said. “I can go six months and never see one, and then I might see five in one week.”
He added that sometimes a hot nail, or a nail driven into the wrong part of the hoof, can cause an abscess. Even if the nail was driven properly, if the shoe shifts, that nail might slide over into the wrong part of the hoof.
“Any intrusion into the sensitive structures of the foot, be it a nail or a rock or separation and debris, can cause an abscess,” Anderson said.
Some horses are more predisposed to abscesses outside of environmental factors. Those tend to be horses with poor hoof conformation and quality, Rhoads said.
“Horses that their feet break off really easily or that are thin-soled are going to be more prone to it,” Rhoads said. “For horses with really nice-quality hooves and good conformation, abscesses would be a lot less common.”
“Some people believe that the white-footed horses have a tendency to get them easier than dark-footed horses; I’m not sure if that’s true or not,” added Dr. Steve Schwartzenberger, a veterinarian and NRHA Professional from Longmont, Colorado. “I’ve questioned whether abscesses go with an underlying cause, like a horse gets sick and gets a high fever for a little while. You get rid of that, but all of a sudden, they’re sore in their feet.
“I think abscesses can tie into the weather and what foot problems a horse has, along with moisture levels and what kind of surface he’s riding on, but they can also tie into general health,” he added. “I had a horse that had an infection, and then his feet got sore. We had to keep them padded for a couple of years after that. Over time, he outgrew it, which makes sense because it takes almost a year to grow a new hoof.”
The Pressure’s On
Because abscesses don’t usually show any external symptoms while they’re brewing, it’s hard to know how long they last from their onset. Once your horse comes up lame, though, abscesses typically take about a week or a little longer to heal, depending on how long the abscess takes to work its way out of the foot. That amount of time can depend on several factors, from how deep the abscess is to how hard the hoof is.
“When you see a sign of lameness, I’d say you want to see some improvement within the first week,” Rhoads said. “What causes the lameness is pressure created by the abscess. We see lameness when the pressure finally hits some of those sensitive tissues or nerves, but the abscess has been going on for some time before that.”
Once your horse is lame, the first thing to do is try to find the abscess with hoof testers, which are like a vice or clamp used to pinch on the hoof until the painful area is located, Schwartzenberger shared. A farrier can do this, although it’s a good idea to have a veterinarian on standby. If the abscess is found, the next thing to do is find the track leading away from the infection.
“Most of the time, abscesses will travel to the point of least resistance, so they’re going to either travel to the bulbs or the hairline at the toe because that’s where they’re going to pop out,” Anderson said. “It’s their nature to want to come out, but as they travel, they damage laminae.”
Bursting through the coronary band isn’t ideal, Rhoads cautioned, as the infection can invade other tissues or even the joint and cause more problems.
“The preferred spot would be at the sole or even the sole-hoof wall junction,” Rhoads said. “When we’re opening those, we don’t want to carve a big hole in the bottom of the foot because then we have to protect that. If you can open it up at the sole-hoof wall junction, those do a lot better, and the horse can get back to work a lot quicker.”
Sometimes the farrier can’t locate the abscess or the track, and a veterinarian will need to do imaging, like x-rays. Otherwise, more damage will be caused to the tissue by digging around trying to find the abscess.
“You have solar abscesses and sub-solar, and those [that you can’t find] become sub-solar,” Anderson said. “At that point, you start soaking, and the only reason you soak is because the warm water softens the hairline and gets things softer, so the abscess will run its course and pop out at the top. You don’t want it to pop out the top if you don’t have to, but in a sub-solar, you’re going to have to let that happen because you’ll cause too much damage getting to it from the bottom.”
Relief Is Near
After opening up the abscess, it’s important to soak the foot in a solution that has osmotic pressure and pulls the pus and bacterial infection from the hoof. The cavity will need to drain to heal properly, and the quicker the infection is removed, the sooner the horse can get back to his normal work.
“A concentrated saltwater solution helps draw the infection to the surface, then we’ll put a poultice on, too,” Rhoads said. “You wrap that, and the sole will soften and draw out the abscess, if you can’t find it right off the bat.”
Once the abscess is open and draining, your horse experiences instant relief. Then, the hole left behind needs to be cared for so dirt and debris aren’t introduced back into the foot.
“I like to mix a little Epsom salt and some iodine, pack it with cotton, and bandage it up,” Schwartzenberger said. “A lot of times, that’s all I need to do. The horse is tender, but if you’ve got a shoe on already, you don’t want to pad over the top of it until you get it drained and dried out.”
Rhoads cautioned to be careful what type of products you use on your horse when treating abscesses. He said in 25 years of practicing, he’s heard of many different potions, and not all of them are good. Be particularly aware of how diluted the iodine is, as it doesn’t take much for the tincture to become caustic.
“Iodine is a good antiseptic, but we use it at about a 0.1% concentration, which is very, very diluted,” Rhoads said. “It’s actually been shown that that percentage is more effective at killing bacteria than higher concentrations. There’s no rule of thumb; no one wants to try to be precise and come up with a 0.1% solution, so we call it a ‘weak tea.’ If you’re going to dilute iodine in water or any kind of fluids, make it the color of a very, very weak tea.”
Remember: The hoof isn’t a dead, unattached part of the horse’s body. Rather, it is a sensitive structure not unlike human skin.
“We have to treat the whole hoof as a living tissue,” Rhoads said. “People are more apt to put harsh chemicals on the hoof [than on other parts of the horse’s body]. They think it’s not living tissue. An abscess on the foot is just like a wound anywhere else on the body, so you don’t want to put anything there that you wouldn’t put on a cut on your arm.”
Not If, But When
Abscesses are a part of equestrian life. Riders can take measures to try to avoid them, but nothing will prevent them 100%.
“If you want to totally avoid abscesses, don’t own a horse,” Rhoads said, with a laugh. “Unfortunately, just because of where horses live and what they do, you’re not going to be able to prevent all occurrences even in the best conditions. But hoof hygiene—cleaning regularly, keeping the stall clean, and things like that—will help minimize the chances.”
For horses that live outside 24/7, Rhoads noted that hooves are good at adapting to the environment they live in. However, wetter conditions will soften the feet, which can lead to more abscesses, although those abscesses will have an easier time finding a path out of the foot to drain. Dry conditions, on the other hand, will harden the feet, which can make it more difficult for abscesses to break out.
Another step in preventing abscesses is maintaining a horse’s well-being, Schwartzenberger added. In keeping with his theory that abscesses may link to an underlying cause, he endeavors to keep his horses, especially those on his show string, which are often exposed to illness, from catching a high fever by staying up to date on their vaccinations and keeping an eye on their general health.
“That combined with good hoof care, like having them balanced and trimmed regularly, can help,” Schwartzenberger said. “In some places, you can get away with them being barefoot when you ride, but there are some places you can’t. You have to deal with your location and not risk bruising your horse’s hoof if you ride him on the rocks a lot, for example.”
All three agreed that even though they’re generally quick to heal, abscesses are a pain. Dealing with chronic abscesses might tempt even the most traditional rider to try one of a plethora of snake-oil treatments that claim to help prevent or even cure abscesses. But while sometimes a simple biotin supplement can help poor feet grow faster, consider each horse on an individual basis.
“I can’t say that [supplements] help prevent abscesses, because you could have the healthiest feet in the world and if something gets into the foot, they can get an abscess,” Anderson said. “But the stronger hoof you have, the better hoof you have, the less chance of getting one. Indirectly, if you’re feeding them [supplements] and their feet are better, there’s less chance of abscesses.”