Thrush is a very common bacterial infection that occurs in the hoof, more specifically, the frog area. This bacteria occurs naturally in the environment, especially in wet, muddy, or unsanitary areas, but is not limited to damp and filthy areas. New research has revealed that thrush lives even in the most sanitary conditions. It grows best with low oxygen (so wrapping is not the best treatment), and horses with a deep sulcus or contracted heels are more susceptible to thrush. Once it’s established, thrush can linger through the driest days!
Research has also found that more often than not, the more your horse moves, the less likely he is to have thrush. Your horse is a lot less likely to get thrush if they are properly trimmed on a regular basis. Sound healthy horses have been known to stand in some filthy stalls and still not get thrush, while horses in poor health (hoof or body) have been noted to have very advanced cases. When your horse is healthy and well balanced and able to move around freely in good pasture/paddocks, the hoof tissue is also healthy. It’s interesting that while it is not contagious, horses in the same barn or pasture typically will have it, though not all of them have it to the same degree. I believe that this has to do with individual health and hoof health (contracted heels, poor trim, lack of trim). I think that immune health also affects how easy the thrush is to take care of, i.e.; if your horse has a poor immune system function, he may be more susceptible to thrush.
You must be diligent in treating thrush. If they continue to live in the same conditions, it is harder to get rid of. It’s important to keep them as clean and picked out as possible, and there are MANY treatment options that are effective. Pay special attention to the collateral grooves (area on either side of the frog) and the sulcus (center of the frog toward the back of the foot). Scrubbing with disinfectant soap and then treating with a thrush treatment is most effective. “Natural” remedies also work like Sugardine (combination of sugar and betadine), a diluted vinegar solution, a tea tree oil/antibiotic ointment mix, Epsom Salts, or there are commercial products like Huuf Magic by Healing Tree, that work well. When used in conjunction with the topical treatments, treatments for the inside out also work well (such as Total Immune Health and/or Hoof Ailments from For Love of the Horse – www.forloveofthehorse.com ).
Using a standard thrush treatment like Koppertox is not recommended. These harsh chemical treatments will also kill good, healthy tissue as well as the thrush. Using anything that you must handle with gloves will likely not be healthy for the hoof either.
MOST horses don’t become lame, but if left untreated, the bacteria can go deeper and result in lameness. You will find that they do not land heel first and your trimmer will notice that the heels grow faster to “raise” the painful frog off of the ground to eliminate pressure that causes pain. Keep in mind that in severe cases of infection, it may take up to a year to regrow a healthy frog! It’s easy to treat if caught early, so clean your horses feet regularly and treat immediately if you or your trimmer notices thrush.