White Line Disease – What is that?

WLD can affect any horse, regardless of gender, age, or whether the horse is shod or not. WLD is an intrusion of fungi and bacteria destroying the tissue of the hoof wall. The penetration of the pathogens can either be favored by extreme moisture (very soft horse hoof) or by extreme dryness (cracks in the hoof wall).

What are the symptoms?

The disease often goes undetected because the fungi and bacteria initially only eat away at the tissue of the hoof wall, causing the white line to change color. Only later do the pathogens starting from the bottom of the foot progress up the hoof wall towards the coronet which results in a gap between the hoof capsule and the inside of the hoof. The resulting pain is manifested by lameness. Most often, WLD is discovered incidentally during routine hoof trimming.
However, White Line Disease is not life-threatening for horses. Only if the disease progresses unnoticed to the extent that the coffin bone changes position within the hoof capsule, it may well pose a threat to the horse and can ultimately lead to reduced performance and lameness. Although the disease appears to be very similar to thrush they should not be confused.

How can White Line Disease be treated?

Since the diagnosis of "white line disease" is usually only made at a very advanced stage when the hoof wall separation has progressed extensively upwards, a resection of the affected area of the hoof will most likely be required. Other treatments make little sense since for a recovery all fungi and bacteria must be removed. A skilled hoof trimmer can remove the part of the hoof wall covering the affected areas. After the resection, the exposed area should be kept dry and clean. The hoof should be checked monthly until all signs of disease have disappeared and the hoof wall has fully regrown.

During the healing process, horse hoof boots are a good way to level the resected areas and protect them from dirt. Nevertheless, the exposed area must be cleaned thoroughly on a regular basis. Depending on the severity of the WLD and the extent of the resection, the horse can usually still be ridden or exercised.

Is prevention possible?

Since the causes of WLD are not well defined, it is difficult to make a statement about prevention. In any case, regular care and checks should be carried out by the hoof trimmer. Since the horse is dependent on its hooves, every change, no matter how small, on the sole or in the hoof wall area should always be examined thoroughly.

Source:

https://aaep.org/sites/default/files/issues/proceedings-06proceedings-z9100106000520.PDF