The Woes of Thrush

(Click on images to make them bigger.)

Warning: The images I have included are there to give information about the frogs and frogs alone. Most of the hooves you are about to see have many other issues and are not considered healthy, so please take this into consideration and only pay attention to the frogs. Thank you.

A healthy frog is very important to the overall health of the hoof and the comfort of your horse. Unfortunately, over 70% of horses have less than stellar frogs, which is the leading cause of pain in the back of the foot. Disease, under-stimulation, over-stimulation, and over-trimming are the most common problems associated with the frog. In this post I am going to address the number one cause of pain in the back of the foot. Thrush.

Thrush is an all-too-present condition in most hooves, and the worst part is it tends to go unnoticed and untreated for long periods of time. In my experience, most people think they know what thrush looks like, but it has many signs that can be missed if you don't know what to look for.

So what are the symptoms of thrush?

 Smell is what people tend to recognize first. As with most infections, thrush emits a very strong, very foul odor. Some have said you can tell a horse has bad frogs just by standing next to them or simply picking up the foot. This can be true, but if a horse has reached such a state where you can smell his hooves just by standing next to him, he has been suffering for a very long time and is at risk for developing infection deep in the internal structures of his hooves.

(Believe it or not, these are the same hoof. Unsanitary stall conditions and nutritional neglect have caused the thrush to worsen and this entire frog is diseased to the point of needing removed. The first picture still had major thrush, but the second picture is unacceptable.)

Thrush feeds off of the dead and dying material that naturally exfoliates from a horse's frog, and sometimes even the sole. It appears as a thick black goop that usually collects in the collateral grooves and the central sulcus. If left untreated, it begins to attack the healthy tissue, which then dies and provides even more food for the bacteria. The frog usually peels off in thin layers as it sheds. This is normal, but these flaps create places for thrush to hide and multiply and should be removed. If your horse has a very flaky-looking frog, it likely already has thrush to some degree, and you need to either remove the dead material or address the issue with your farrier.

(The first hoof had thrush so deep that everything above that seeping crack had to be removed.)

A deep central sulcus is another cozy place for thrush to feed and multiply. When left without treatment, a crack slowly forms in the sulcus that can reach between the heel bulbs and all the way to the hairline. Usually these cracks are so deep you can stick the entire end of a hoof pick inside and it will stand on its own. Every time the horse places his hoof on the ground this crack opens slightly, causing a great deal of pain.

(See how deep the central sulcus is here? This is incredibly painful, and often the horse will try to pull away if you attempt to pick it out.)

So what do you do?

Most thrush is not as severe as the examples shown here, but if you suspect your horse has thrush, there are several things you can do.

1. Keeping the hooves clean is a great way to start, and it's not as difficult as you might think. Hooves are always dirty, but even a quick job with the hoof pick once a day will help prevent or eliminate thrush.

2. Make sure the exfoliating material is trimmed off regularly. This can easily be done at home with a pair of small scissors or shears.

3. Medication of some sort is almost always required to treat even the mildest form of thrush. My favorites are Vetericyn(applied twice daily), Pete's Goo(a 50/50 mix of athletes foot cream and triple antibiotic), No Thrush powder(the first and only dry formula and it works wonders), and Clean Trax(for serious thrush and stubborn infections). Most of the commonly sold applications, however, are actually quite damaging to the hoof. Will they get rid of thrush? Most likely, yes. The problem with these harsh products is they not only kill the infection, but they kill living tissue as well, which can create the thrush cycle all over again. The three methods I mentioned are gentle on living tissue and are the most effective products I've used.

When you are applying your treatment, make sure it reaches the deep crevices where the thrush is breeding. Bacteria like warm, wet, and dark places. Those crevices are a cozy little home for any kind of infection. The central sulcus can be difficult to treat, but with some patience you can treat it properly without causing too much discomfort to your horse.

(These hooves have begun to heal. The central sulcus is opening up.)

(Here you can see great improvement. While not perfect, it is getting there. These results were achieved through twice daily applications of Vetericyn spray. I absolutely love this product. This horse lived in an unsanitary stall 24/7 that wasn't cleaned daily. I thought the thrush would never heal in that environment, but the results speak for themselves.)

I hope this helped shed some light on the often elusive plague on our horses' frogs. If you have any questions, or feel I could be clearer on something, please let me know. Thank you!