M

MAIN EXTENSOR TENDON: see: Common Digital Extensor Tendon
MALNUTRITION: Significantly inappropriate diet. This is not limited to underfeeding, but also includes overfeeding and excessive or insufficient amounts of individual nutrients in the diet.
MARE: Sexually mature female horse usually 4 years old or older. a.k.a.: dam ("out of").
MARK FISHER: First American anvils produced in 1843. Cast steel faces welded to a cast iron bodies, rather than forged anvils.
MASTER: (1) Traditionally, a tradesman who is proprietor of his own business. Especially if that business employs others. (2) A trainer of apprentices.
MEDIAL: Inside, toward the center line of the body. The inside half of the limb. See also: Lateral.
MEDIOLATERAL BALANCE: Describes the distribution of loading over the medial and lateral halves of the hoof.
MORPHOLOGY: The study of biological structures without consideration for their function.
MULE: Offspring or progeny of a jack and a mare.
MULE FOOT: A narrow hoof with straight quarters and a large frog.
MULED HEELS: Paired extended heels on a horseshoe.
MUSTAD: Swedish-based horseshoe nail manufacturer since 1885. Mustad currently owns Capewell and Cooper horseshoe nail companies, as well as a division which produces glue-on horseshoes and polyurethane-clad aluminum horseshoes. Mustad also produces hoof treatment chemicals and horseshoe calks.