In order not to disfigure the hoof unnecessarily, the horn below the cleft should be kept in place as long as possible by shortening the wall at that point, to remove shoe-pressure, and by driving no nails into it. If, however, the horn is loose and about to come away, it should be removed and the defect filled with Defay’s patent horn-cement.
3. Loose Wall.
Separation of the wall from the sole in the white line is called loose wall ([Fig. 223, a]).
Occurrence.—Frequent on the fore-hoofs of shod and unshod horses, and oftener upon the inner than upon the outer side. More rare on hind hoofs. Common-bred horses with wide and flat feet are predisposed to this trouble.
We distinguish superficial and deep loose wall; only the latter requires the shoer’s attention, because it leads to lameness.
Causes.—Walls which are very oblique (slanting); outward bendings of the plantar border of the wall; burning the horn with hot shoes; dryness; neglected shoeing; excessive softening of the horn with poultices, particularly of cow-dung; carelessness in preparing the bearing-surfaces of hoof and shoe in shoeing; uneven fitting of the shoe.
Treatment.—It aims to remove the lameness and to favor growth of coherent horn. In the first place the removal of the exciting causes, followed by proper shortening of the wall. We should apply a shoe whose bearing-surface inclines slightly downward and inward, is perfectly smooth, and wide enough to cover the wall, white line, and outer border of the sole; the iron should be only moderately warm. Where there is lameness we use a leather sole with packing, or a bar-shoe. The loose wall should be freed from shoe-pressure only when it does not extend far along the white line. When the separation is extensive the loose wall should not be lowered. The crack should be filled with wood-tar, crude turpentine, or soft grafting-wax.
If a loose wall occur upon the foot of a horse while running barefoot, all separated horn should be removed; if, on account of the nature of the ground, this seems to be impracticable, the hoof must be shod.
Care of the Hoof.—Shoe at least every four to five weeks. Preserve the pliancy and toughness of the horn by judicious moistening.
4. Hollow Wall.