A: White line disease is an invasion of opportunistic bacteria, fungi and probably yeast that has the ability to consume the inner horn of the hoof.
This infestation leaves the tell-tale sign of a white chalky material with the odor of rotting sweet fruit. It will work its way up the interior hoof wall, leaving a hollow space.
It generally invades at the heels and quarters and may work its way around the inner perimeter. It is misidentified more often than not.
An effective, inexpensive treatment identified by the late Burney Chapman was cleaning out the debris and treating the area with Merthiolate (now available in the U.S. under the name Mersol).
I recently treated what appeared to be the early stage of white line disease by working with a local veterinarian and administering immune-system-
enhancing medications. We did this with the idea that an immune deficiency may be contributing to this young horse’s susceptibility to the invasive entities. This horse was treated for 6 weeks and its hooves were clean at the next trim.
It could have just been a coincidence or what we saw may not have been white line disease. But, it also could be an answer. I will try this procedure again in the future.
It is not necessary to debride the hoof wall to get at the affected area if it is identified and treated early.
—Jack Millman, Worthington, Mass.