This is a defect in the action of the limbs which allows the toe of the hind shoe to strike the under surface of the corresponding fore one. The point struck varies in different cases, and may be anywhere between the toe and the heel. The striking point of the hind shoe is the toe and parts to right and left of it. Besides the loud clacking noise produced by this disordered movement, the heel of the fore-foot may suffer injury, the shoes may be pulled off, or the animal may be thrown down by locking of the hind and the fore shoes.
Fig. 407. - Forging.
B, B, Points struck in forging; C, c, Points on Toe of Hind Shoe which strike the Fore Shoe. D, Toe of Fore Shoe with inner edge bevelled.
As in overreach so in forging, conformation must be recognized as a predisposing factor. Leggy horses with short bodies, and others whose hind limbs are too much inclined forward, display a special liability to this defective movement.
Young animals, however well set up, when weak or fatigued by overexertion, frequently forge until an improved condition is established. Loose and careless driving encourages any tendency to it that may exist from the causes referred to above.
Forging is sometimes determined by defective shoeing. The hind-feet are not only allowed to grow unduly long, but the shoes are fitted full and given too much prominence at the toes. Where these conditions are allowed to exist behind, they are almost invariably present in front as well. It results from this that the long fore-feet do not clear the ground before being overtaken and struck by the long hind ones.
The feet in these cases may not appear to be of undue length, but in relation to the peculiar long-striding action of the animal they often prove to be so.
To guard against forging, it is important that horses be driven well up to the bit at a moderate pace, well fed, and not overworked. The fore shoe should be narrow and well seated out on the ground surface, and the foot restricted in length.
The hind-foot should be shortened at the toe, and the shoe fitted well under the crust, so that the latter is somewhat in advance of the former. It is also desirable that the toe of the shoe should be nicely rounded off, the heel allowed to take its natural bearing instead of being raised by calkins.