This is a severe bacterial/ fungal infection which affects the frog, heal and underlying structures of the hoof.
Horses At Risk From Canker
Due to the fact that canker can infect the very inner parts of the horses hoof it can be very difficult to treat. If caught early enough then all the diseased parts of the infected hoof are removed and a careful antiseptic cleaning program begins along with antibiotics to help the structures to rebuild.
However once canker has taken hold it can take several weeks/months for the horse to recover depending on the severity of the canker.
Good stable management that ensures that stables are regularly mucked out and the horses are kept on clean dry bedding along with regular hoof care such as regular farrier visits and daily picking feet out will all help to prevent this infection from occurring. Quick treatment of any infection is essential as it will prevent the infection from damaging internal structures for which sometimes there is no return.