Thermazene

White line disease is an interesting disease and one that might mean there is a bigger problem. Interestingly WLD almost always is in feet that are in poor health. What WLD may be telling you is you have poor circulation due to mechanical failure (flat or prolapsed soles). Poor circulation results in a higher concentration of anaerobic blood in the hoof and less aerobic blood to nourish cells within the hoof. One method that is working well is to use Thermazene cream topically in the affected areas clean the tracks out as best you can. Apply cream then use a 2" or 3" cast covering as much hoof wall as possible. Cast and let dry now check the bottom of the hoof if you do not have concavity either apply a 2" cast-like a rim pad or glue an aluminum St Croix Event type shoe. This will raise the sole off the ground creating concavity and proper hemodynamic & lymphatic biomechanics. I believe you have to create the proper structure for efficient biomechanics.