You might guess that it’s some sort of hoof issue that involves the white line of your horse’s hoof. Well, sort of. Technically, white line disease resides between the stratum medium and the laminar horn of the hoof wall. The laminar horn attaches to the laminae, if you guessed that this is BAD, you are correct. You may also hear it called seedy toe.
You will typically see white line disease during a Farrier’s visit, very close to the white line. There might be a crack in the toe or quarter area, or you might see some hoof wall separation, or there’s a bit of chalky debris where solid hoof wall should be.
These cracks are commonly called "seedy toe".
If only it was easy to say it’s caused by X,Y, and Z! There have been over a dozen identified fungi and bacteria that create white line disease. Each case is going to be different. And therefore each case will respond differently to treatments. It is known, however, that air and light do wonders to kill white line disease.
But how does your horse get white line? There are about as many reasons for this as there are microbes involved. Your horse’s genetics, conformation, and living environment are big factors. As are how regular his Farrier care is, how well his hooves are balanced, if he’s knocked himself, gone through a wet/dry cycle over and over, if he’s exercised enough, and even what his diet is.
If you even suspect white line disease, your Veterinarian and Farrier can come up with a plan. Some cracks can be opened up while they are small. If the infection seems larger, it’s often a good idea to do some X-rays of the hoof. Pockets of infection will show up on radiographs. This also gives your Veterinarian and Farrier a map to start opening up the infection. In some cases, large sections of hoof wall need to be removed. This physically removes the infection and allows air in.
You may also need to treat your horse’s hooves with a Vet approved concoction, like Steri-Hoof, to work on killing the infection. A change to a horse shoe might also support the frog and bars if the hoof wall has too much damage. As only time will grow back the hoof, it’s important to have your horse on a well-balanced diet as well, providing for optimal hoof growth.
In some cases of white line disease, a horse may develop laminitis. Damage to the hoof wall translates to decreased support in the hoof, and the laminae might begin to fail. The best course of action is one of quick intervention, working with your Farrier and Veterinarian to prevent worsening of white line disease into lameness or Laminitis.
Daily hoof care and regular farrier visits go a long way to preventing severe cases of white line disease!