06/19/2025
Q&A: White Line Disease
Q: What is White Line Disease?
A: When a horse has some degree of hoof wall separation, it becomes a cavity for bacteria and fungi to grow and further break down the hoof's structures. If left untreated, it can cause mild to severe lameness, as it extends upward, eventually reaching the coronary band.
Q: What causes it?
A: While there is no exact cause known, there are many factors at play. Conformational hoof deformities, such as clubbed hooves or long-toed underrun hooves, can predispose a horse to white line separation or stretching. Mechanical factors caused by improper trimming, or horses who have undergone lamanitis to some degree could also be a cause for separation. If the horse's toe is left too long, this causes excessive strain on the hoof's structures, as well as the tendons and ligaments up the leg.
Once there is hoof wall separation, bacteria or fungi become can become trapped, developing into White Line Disease. Commonly this occurs when the horse is in wet/muddy conditions, or when the weather is hot and humid, allowing for a breeding ground of bacteria.
Q: How do I know if my horse has White Line Disease?
A: Commonly, the horse will be sound until the condition has progressed to a more severe stage. If you are cleaning out your horse's hoof and it has a cavity between the sole and hoof wall, and you notice grey/white crumbling or your hoof pick is able to go in rather deep, consult your hoof care professional to evaluate the situation and to discuss the best course of action for treatment.
Q: How do I treat it?
A: Your farrier may do a small or large resection of the hoof wall, depending on the severity. This means they will cut away the infection, and expose the clean healthy hoof structures for new growth, and to prevent any bacteria from getting trapped again. They may also recommend you treat it with a spray or soak to keep it clean, or may fill it with medical putty. It is important to keep the hoof as clean and dry as possible during the recovery to prevent regrowth of bacteria.
Q: How can I prevent my horse from getting it?
A: Routine hoof care including regular cleaning and proper trims, and making sure your horse is on a proper diet to prevent separation due to lamanitis is a good start. Some hoof supplements have been known to help maintain the integrity of the hooves, minimizing risk. This isn't always preventable, however, but catching it early on and treating it right away with the help of your farrier is the best way to ensure your horse has a smooth recovery!
True or False:
Horses with shoes can't get White Line Disease.
FALSE
Horses are actually no more likely to develop WLD whether they are barefoot or shod. Infact, the mechanical stress of the nails has even been linked in some cases.
