What's up with Thrush??  What is it, and how do I get rid of it?


What is thrush?  It’s a pretty gross bacterial infection of the hoof, most commonly seen in the sulci (or grooves) and frog area.  The bacteria is anaerobic, so it lives without oxygen, perfect under a hoof, right?  Advanced cases can extend to the sole and white line, and when thrush affects the sensitive areas horses can become lame.  

New research tells us that thrush is not discriminatory, it can affect horses that live in pristine “poop never hits the ground” stalls, while rarely infecting some horses that live in mud.  (Although proper care must be taken during the treatment process to keep the hooves clean and dry.)  Researchers have found that it’s more often the horse not “self cleaning” the hoof by walking, which flexes and contracts the hoof anatomy, that accounts for thrush.  


You can barely see the black stuff in the grooves.  This is thrush!  I smelled it before I saw it.  


After application of thrush medication.  You may also need to apply around the frog, and around the rim of shoes, or the edge of an unshod horse. 


What we see during a case of thrush is a black paste.  However, it’s likely that a Groom will smell it before you see it!  The distinct, rancid odor of rotting flesh is a sure fire sign of thrush.  

So how do you treat a case of thrush?  Most over the counter topical applications are affordable and easy to use.  Make sure the hoof is clean and dry before you apply!  Begin by cleaning away the blackened, diseased tissue.  You may want to have your farrier or vet help you with this.  Clean the hoof!  You can use a high pressure hose nozzle to do this, but be diligent about not using too much water.  After the hoof has dries, apply your topical treatment.  A mild case should clear up quickly (under 3 days.)  For cases that don’t clear up quickly, or have gone deeper, please consult your Veterinarian.  Lameness is a very real possibility.  Your Veterinarian can help you with stronger and sometimes systemic options.  A very good option available from your Vet is   a tube of antibiotic ointment typically used for mastitis in cows.  

I know some of you like to use bleach or hydrogen peroxide.  I do not suggest using these products, the hoof is living tissue that is damaged and wounded by thrush.  Research tells us that bleach and hydrogen peroxide actually lengthen the healing time and can cause significant pain.  (I wouldn’t want to put bleach on my skin, much less an open wound!)  There are lots of great options available to you at your local tack or feed shop.  (And most are either purple or green!)


A ketchup bottle is a great place for thrush meds.  Pointy applicator.


And speaking of purple and green medications, they typically are the messiest and most difficult thing to apply.  I have found the easiest way to apply them is with a spray bottle or ketchup bottle from a kitchen supply store.  The tiny nozzle contains most of the drips and you can better control the application.  

Of course, I asked our resident Farrier, Ernest Woodward, to weigh in also.  Here’s his take:

“Think of thrush like a wound, no amount of neosporine and bandaids will help, if you don’t clean the wound first it will stay infected.  The best place to start is the wash rack.  Put your sprayer on jet, point it at the hoof, count to at least 60.  A minute or so of water picking can get out all the gunk deep in the cracks that no hoof pick can get to! Then a treatment of mild betadine solution with a good scrub, rinse and repeat a few times before you let the hoof dry and medicate.  Keep at this and you can get some really good healthy hoof growth, and you can dial it back and just do a maintenance routine."


Clean the thrush out!  Then your treatment of choice. 


After application of your chosen medication, try and keep everything clean and dry.  There are some great over the hoof boots that can be used temporarily to help the healing process.  The bottom line is to be super diligent about picking and inspecting your horse’s hooves.  If you see (or smell) something funky, start to treat right away!