White Line Disease in Horses

Last Updated on February 22, 2022 by Allison Price

What is White Line Disease?

White line disease, a fungal infection of the horse’s hoof, can cause splitting of the hoof wall at the white line (inner soft and fibrous layer) or infection around the nail holes. The infection can lead to fungus, bacteria, or both, infiltrating the hoof wall. As the infection progresses, the crack will grow larger and a foul-smelling substance will be found in the crack. The attachment to the hoof’s inner and outer walls will be compromised by the growing crack. The disease can progress to the point where it is difficult to shoe and keep the shoes on the horse. This could lead to the horse becoming lame. This disease is also called stall rot or hollow foot, wall-thrush, seedy toe, and/or stall rot.

White line disease is when the hoof wall splits or cracks. This can be caused by unusual stress, and bacteria and fungi can often be found within these cracks.

Horses are susceptible to White Line Disease

White line disease is a condition in which a horse’s hoof wall becomes separated from the non-pigmented portion of the hoof capsule. The hoof wall may have a small, powdery area along its edges. Soles may feel tender. You may also notice warmth in your horse’s feet, slowing down the growth of his hoof wall and discomfort when your horse puts weight on his hoof. You may notice a hollow sound in the area where the hoof is affected by tapping on the wall at the outside of your horse’s toe. In extreme cases, you may see lameness.

  • White line disease may occur in any one or more hoofs.
  • Separation and removal of the hoof wall
  • Powder-like substance on the hoof wall
  • Warmth at the feet
  • Pain
  • Lameness (severe instances)


White line disease can be a primary condition, or it may occur secondary to other disorders of the hoof like club feet. In severe cases, the loss of support from the distal phalanx may cause displacement, leading to lameness.

White Line Disease in Horses

White Line Disease in Horses: Causes

White line disease can be caused by the following factors:

  • Living in a humid or damp environment
  • After laminitis, you may feel stressed.
  • Injury to his hoof
  • Extra long toes can cause stress where your horse’s hoof meets the sole of his foot.
  • Unclean bedding and living quarters
  • Insufficient nutrition

You may find that your horse’s hoof is more susceptible to fungi if it is exposed to extreme dry or wet conditions. It is important to practice good hoof hygiene in such situations.

Horses that are not walked on pasture and unshoed rarely contract the disease. Horses that have been walked a lot, are not trained, and live in damp conditions will be most at risk. This increases the chance of bacteria, yeast, or fungus invading the hoof wall.

Diagnoses of White Line Disease in Horses

You should contact your veterinarian or farrier if you have concerns about your horse’s white line disease. To diagnose white line disease, your horse must undergo a thorough physical exam and radiographs. This will determine whether or not there is separation of the hoof wall.

Horses with White Line Disease

To remove abnormal stress from the hoof wall, corrective trimming is necessary. The hoof wall should be separated and debrided. If the debridement is done correctly, there is often no need to use antiseptic treatment. A tincture of Iodine can be applied topically to the feet for as little as one week. Equine foot formulas with chloroxide can also be used. Horses should be kept as dry and healthy as possible. Corrective shoes are essential to give support and relieve stress to the feet. White line disease can be treated early to prevent problems. If left untreated, it can cause damage to the hoof wall, and eventually lameness.

Horses are now immune to the White Line Disease

You must ensure your horse is clean and tidy with his hoofs. This includes regularly picking his feet. Regular hoof checks can help you spot early signs of whiteline disease. Although treatment can take time as the hoof wall must grow back and replace the damaged area, it is crucial that the condition does not get worse.

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White Line Disease Advice and Questions from Veterinary Professionals

Allison Price
Allison Price

I’m Allison, born and raised in San Diego California, the earliest memory I have with horses was at my grandfather’s farm. I used to sit at the stable as a kid and hang out with my Papa while he was training the horses. When I was invited to watch a horse riding competition, I got so fascinated with riding!