Identify and Treat Canker in Horse Hooves

By: Danvers Child, Certified Journeyman Farrier and Hoof Health Consultant | Updated March 23, 2025

The term "canker" is used in many different contexts. So, when people hear "equine canker," they may have misconceptions about what it really is. Although the word is linked to "cancer," equine canker is not a form of cancer. Similarly, while it may sound like a "canker sore" in humans, this condition is not a minor issue that will heal on its own.

What is Canker in Horses?

Equine canker (also known as hypertrophic pododermatitis or proliferative pododermatitis) is an overgrowth of hoof horn tissue on the bottom (solar) surface of the horse’s foot.

Causes of canker

While the exact causes are unknown, the condition is generally considered to initiate with a bacterial, fungal, and/or viral infection resulting in a rapid proliferation of long fronds of keratin, the primary component of the hoof.

Canker may appear in any breed, gender, or geographic location. However, there is a higher incidence in draft horses, stalled horses with little exercise, and in the southeastern U.S. The condition is relatively uncommon and, although exact numbers are not known, it affects a small percentage of the horse population.

Canker can affect one or multiple hooves

While equine canker is most often found in the hind feet, it can occur in the front as well. Likewise, although the condition generally occurs in one or two hooves, it can be found in all four.

Development of Canker in Horses

In its initial stages, canker usually establishes in the central or collateral sulci (grooves) of the frog, although it quickly spreads and affects the entire frog. If left untreated, the condition will tend to spread and proliferate throughout the solar region of the hoof, encompassing the bars, sole, and weight-bearing portion of the hoof wall.

Signs and symptoms of canker in a horse’s feet

In its initial phases, equine canker usually appears as a white or grey area of growth that looks similar to a wart or a small cluster of warts. In the early stages, canker’s appearance can easily be confused with proud flesh or thrush. Unlike proud flesh, canker is highly sensitive to the touch, nor does it produce the dark, tar-like discharge that is characteristic of thrush.

As the condition advances and proliferates, it develops a more distinct appearance and begins to have a sponge-like tendency. This eventually develops into the cauliflower or crabmeat look that is almost always used to describe the fully developed condition.

Throughout canker’s development and growth, the hoof condition progressively becomes more wet, soft, and sensitive. A moist white or yellow discharge (like cottage cheese) will often develop, along with a distinct, foul odor. The associated lameness and bleeding may become more significant.

Diagnosis and Treatment of Canker

Due to its unique and distinct appearance, advanced cases of equine canker typically don’t require advanced diagnostics. Advanced cases can be spotted by the average equestrian, and early onset is easily identifiable by professional farriers. No matter how early the condition is discovered, however, all cases require aggressive veterinary treatment.

In virtually all cases, surgical debridement (cutting away abnormal tissue) is initially required. In some instances, veterinarians will choose alternative and/or accompanying approaches, such as cryotherapy. Due to excessive amounts of bleeding and high levels of sensitivity and pain, these procedures are usually performed under a local or general anesthetic.

Recovery and prognosis

Once the affected or infected area is removed, your horse’s hoof will require daily cleaning, medicating, and bandaging for a few weeks to a few months, depending on the severity of the condition and the response to treatment. Due to the proliferative nature of the condition, it is quite common that multiple treatments are necessary to ensure that all of the affected tissue is removed. Your horse should be kept in a clean, dry environment throughout recovery.

Ultimately, the prognosis for full recovery and normal hoof growth is positive, although it is directly influenced by early detection, aggressive treatment, and vigilant maintenance during recovery.

Additional Horse Owner Resources

• Fundamentals of supporting healthy hooves
• See a year in the life of a healthy hoof
• Glossary of the parts of a hoof