The bacterium involved is Fusobacterium necrophorum,[1] and occurs naturally in the animal's environment—especially in wet, muddy, or unsanitary conditions, such as an unclean stall—and grows best with low oxygen.
Treatment for horses with thrush includes twice-daily picking of the feet, taking special care to clean out the two collateral grooves and the central sulcus.
The feet may then be scrubbed clean using a detergent or disinfectant and warm water, before the frog is coated with a commercial thrush-treatment product, or with iodine solution, which may be soaked into cotton balls and packed into the clefts.
[2] Several home remedies are used, such as a hoof packing of a combination of sugar and betadine, powdered aspirin, borax, or diluted bleach.
[2] In general, thrush is relatively easy to treat, although it can easily return and it can take up to a year for a fully healthy frog to regrow after a severe infection.