By: Dr. Lydia Gray, SmartPak Medical Director/Staff Veterinarian
Canker (hypertrophic pododermatitis) is an overgrowth of hoof horn tissue on the bottom surface of the horse’s foot. This abnormal production of keratin--which resembles soggy cauliflower and may have a cottage cheese-like discharge--usually begins in the frog but may spread to the sole, bars, and even the weight-bearing portion of the hoof wall. One or more hooves may be affected, and while the condition is more common in the hind feet, it can occur in all four limbs. It may appear in any breed, gender, or location, but there is a higher incidence in draft horses, in stalled horses with little exercise, and in the southeast U.S.
Like many conditions of the hoof, because the cause is not well understood (some combination of trauma and bacterial infection), there are a wide variety of treatments that may or may not be effective. It is best to involve both the veterinarian and the farrier in treating the condition, as surgical debridement (cutting away abnormal tissue) under local or general anesthesia is initially required, along with a thorough trimming. Once the infected area is removed, the horse 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.
The prognosis for canker is guarded, although it is unlikely to recur once completely healed. A prompt diagnosis is important to a successful outcome, especially as it can be mistaken for thrush in the early stages. However, thrush destroys or eats away tissue and produces a tar-like substance while canker causes tissue to proliferate or grow and has a similar appearance to off-white, rotten cauliflower. While canker can be painful when touched, the presence of actual lameness may mean the disease has advanced and needs aggressive treatment.
SmartPak strongly encourages you to consult your veterinarian regarding specific questions about your horse's health. This information is not intended to diagnose or treat any disease, and is purely educational.