Canker and Thrush in a Horse's Hoof

January 10, 2011 (published)

Today on Texas Vet News I am going to talk about two different infections in the horse's foot called canker and thrush. Canker results from a bacterium that causes the tissue in the frog and heel bulb region of a horse's foot to grow or proliferate abnormally. Lesions can be very small or can cover a large part of the horse's sole, and they are generally painful and cause lameness. Diagnosis of the disease requires your veterinarian to take samples of the tissue and send them to a lab for diagnosis as the condition can resemble proud flesh. Treatment of the condition can be difficult and requires complete surgical removal of all infected tissue and removal of surrounding tissue. After surgical removal, the infected area should be frozen by using cryotherapy and then wrapped with a mixture of benzoyl peroxide and acetone with crushed metronidazole tablets made into a paste. The most important part of aftercare is keeping the foot dry until it heals.

Another foot infection is called thrush and although it is usually not as severe as canker, it can cause lameness. Thrush is a bacterial infection that usually affects the frog and causes a dark discharge on the foot that has a foul smell. Treatment consists of removing damaged tissue and treating the foot with any commercially available thrush treatment. The foot must also be kept dry, but wrapping is usually not necessary or recommended. Preventing thrush requires regular hoof care and keeping horses in a dry environment. Because thrush commonly occurs in horses with contracted heels and deep sulci, correct trimming of the foot can go a long way in preventing thrush from developing.

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