Vitiligo refers to a skin depigmentation from an unknown cause while the terms leukoderma and leukotrichia are used to decribe pigmentation loss in skin and hair, respectively...
The good news is that the depigmentation is unlikely to cause any health problems.
Leukoderma and leukotrichia often develop in areas of trauma and inflammation, consider the white hair regrowth from saddle sores one sometimes sees under poorly fitting tack.
Dermatology diseases such as onchocerca infestation, lupus, frostbite, burns, or sun damage can result in leukoderma. Reticulated (linear) leukotrichia is a genetic skin disorder found in Quarter Horses, Thoroughbreds and Standardbreds. It appears as a broken or wavy line of depigmentation down the topline of these horses. The skin is otherwise completely normal; the hair color is the only change.
There is a rare form of depigmentation called Hyperesthetic leukotrichia, in these cases the depigmented hairs are exquisitely painful.
Spotted leukotrichia is similar to the reticulated, but appears instead as multiple, body-wide spots of hair depigmentation. Arabians may develop vitiligo, undergoing a skin depigmentation for unknown reasons. The areas may spontaneously repigment in a few years.
Treatments for the actual depigmentation consists of treating any obvious underlying disorder such as removing trauma, deworming, and preventing sunburn or frostbite.
Steroids and anti-inflammatories have been attempted in some depigmentation cases with varying degrees of success. However some horse books simply state that there is no treatment.
McDowells Treatments
I recommend an external oil that is rubbed onto the area consisting of a mix of the following.
- Hypericum - for nerve endings,
- Cajuput - stimulates circulation,
- Cod Liver Oil- high in A and D vitamins ,
- Wheat Germ Oil- high in Vitamin E.