The crack may be immobilized by the metal plate, or by narrow ticking bandage or adhesive tape wound a half dozen times around the hoof, in conjunction with a bar-shoe, Chadwick spring, leather sole and tar and oakum sole-packing.
In dressing the hoof, the side containing the crack should be spared, the opposite side lowered, the object being to shift the weight and consequent expansion into the sound quarter. When the affected quarter is deficient in length the branch of the shoe beneath should be made thicker, even to the extent of causing it to ground in advance of the opposite branch.
Next to shoeing, rubber hoof-pads render good service, because through them a part of the body-weight is distributed over the sole and frog. They assist in widening the hoof, and lessen shock when the foot is set to the ground. These are all matters which favor the growing down of unbroken horn.
When the crack gaps widely, and the frog is small and deep in the foot a shoe with bar-clips (Defay’s shoe), or a Chadwick spring, with bar-shoe and leather sole may be used. It is not impossible, indeed, to obtain a cure by using an ordinary open flat shoe, though much will depend upon the other lesions that may be present, the nature of the hoof, and the service required of the animal.
If the edges of the crack are irregular and overlapping, they should be carefully thinned away. Thinning the horn on both sides of the crack over the coronary band, preventing drying out of the horn, and frequent applications of carbolized oil to the coronet favor growth of undivided horn and guard against a renewal of the crack.
If in the beginning of the disease there is inflammation and lameness, cooling poultices should be used for several days. When there is no lameness, the horse may be used for slow draft purposes. Coach-and saddle-horses should be kept from fast work until sound horn has grown down at least one-half of an inch from the coronet.
Bar-cracks are usually the result of changes of position of the quarters, and are just as frequently brought about by contraction as by leaving the quarters too high. We see them almost entirely upon the fore-hoofs. They seldom occur alone, but are usually accompanied by corns. When the crack extends to the pododerm there is a superficial inflammation of the pododerm and lameness. When treatment is not promptly begun the inflammation extends to the deeper layers of the pododerm, or, indeed, even to the plantar cushion, and gives rise to swelling of the bulb of the heel upon that side and to a well-marked lameness, which requires treatment by a competent veterinarian.
Ordinarily a bar-crack is only found by a close examination of the hoof after the shoe has been removed. In paring the hoof the crack usually appears as a dark streak, sometimes as a bloody fissure; not infrequently grayish hoof-pus is discovered in the depths of the crack.
The treatment must be directed towards favoring the growth of a continuous (unbroken) bar. This is accomplished by completely removing the edges of the crack, paring the horn of the vicinity very thin, and preventing the least pressure upon the wall of this quarter by the shoe, by lowering this quarter with the rasp and applying a bar-shoe with leather sole.
Following the removal of the edges of the crack there often appears, especially in stumpy hoofs, a deep groove; if the bottom of this groove is moist, we should pack it with oakum wet with a five per cent. solution of creolin or carbolic acid, and cover the oakum with wax (grafting-wax). The cracks will return if the exciting causes cannot be completely removed.