Veterinary advice should be sought before applying any treatment or vaccine.


Canker is an uncommon hoof infection that usually occurs in draft horse breeds living in poor sanitary environmental conditions. The infection is caused by an intracellular microorganism that attaches itself to the frog and heel bulbs within the horse's foot. The organism causes abnormal keratin production, resulting in the development of proliferative painful cauliflower-like masses and yellow-white tissue along the frog and heel bulbs. Sometimes necrotic areas develop, which produce foul-smelling caseous exudate.

Canker can easily be mistaken for thrush in the early stages of the condition, as it generally originates in the frog of the foot. If canker is left untreated, it will progress to the other parts within the foot and in severe cases, the adjacent hoof wall. Depending on the severity of the infection, the horse may or may not be lame.

Treatment for canker requires surgical debridement of the abnormal tissue, cryotherapy, and thermal cautery in order to fully remove all the abnormal tissue growth. Some veterinarians use a metronidazole/oxytetracycline combination paste following surgery to help with treatment. During recovery and following treatment, horses need to be kept in a clean, well-maintained environment where the feet are kept clean and dry. However, during recovery it is even more important that the hoof is kept protected.


Proliferative painful masses
Tissues loosen easily
Yellow-white tissue covering the frog and heel bulbs
Foul odor
Caseous white exudate resembling cottage cheese
Bleeds easily
Painful to touch
Varying degrees of lameness


  • History
  • Clinical signs
  • Physical Exam
  • Biopsy


SurgerySurgical debridement performed standing under sedation or under general anesthesia
Antimicrobial therapyTrimethoprimsulfa or metronidazole coupled with topical application of metronidazole/oxytetracycline powder.
Hoof protection devicesBandages or hospital shoe
Environmental modificationProvide a clean, dry, sanitary environment for horses to stand on.


  • Maintaining good sanitary practices in horse stalls and in pastures, especially in high concentrated areas such as adjacent water troughs or shelter structures.
  • Regularly clean stalls
  • Provide clean, dry, quality bedding in horse stalls, that is at least 3 inches deep.


Scientific Research References

Good Overviews

  • horse sweating icon
  • canker icon
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Risk Factors

  • Keeping horses in poor sanitary environments, such as accumulation of manure and/or urine, excessive mud, and constant flooding or excess water
  • Draft horse breeds

Also Consider

Commonly Affected Breeds

Percheron icon