What Creates the Foul Odor of Thrush?

A strong rotting smell is a well-known indicator of Thrush. If you’re a farrier or horse owner, you probably know the smell well. For those unaccustomed to the smell, it is like that of a rotten egg. The odor radiates from the hoof, making regular hoof cleanings and farrier work more foul-smelling than usual. So, what causes Thrush to smell? In this blog, we will sniff out the answer to this question.

Hoof Anatomy and Structure

Your horse’s hooves are comprised of connective tissue proteins. Connective tissue is rich in the mineral sulfur. The sulfur provides the “welds,” or crosslinks, in the connective tissue protein. These crosslinks are responsible for the structural integrity of the hoof capsule. If the bonds are weakened or destroyed, the structural integrity of the hoof will be compromised.

Thrush and the Microbial Invasion

Thrush is an invasion of “hoof-eating” microbes into the connective tissue of the sulci surrounding the frog and heel. These anerobic microbes thrive in low oxygen environments, such as the deep sulci and clefts surrounding the frog. Once the organisms begin dividing in the frog sulci, the stage is set for a progressive invasion and infection.

How Thrush Affects the Hoof

The anerobic microbes consume the connective tissue proteins, including the sulfur, and excrete volatile sulfur compounds as waste. The rotten egg smell we associate with Thrush is the odor of the sulfur being released by the microbes. The same smell occurs during hot-shoeing. The odor produced is the smell of sulfur gas from burning the sulfur-rich connective tissue proteins of the hoof.

Thrush can be devastating to the hoof. As the sulfur crosslinks are destroyed the connective tissue becomes weakened, compromising the structural integrity of the hoof.

It is important to talk to your veterinarian and farrier if your horse develops Thrush. Regular use of a non-caustic hoof topical, such as Life Data® Hoof Clay® and Farrier’s Finish®, can be used as a measure against Thrush. Adding a balanced hoof supplement, such as Farrier’s Formula® Double Strength, to your horse’s diet can also help build a stronger hoof capsule that is more resilient to infections and other hoof related issues. If you have any questions, feel free to contact us at 1-800-624-1873.