* * *
Each steer or spayed heifer imported into the United States from Mexico shall be identified with a distinct, permanent, and legible “M” mark applied with a freeze brand, hot iron, or other method prior to arrival at a port of entry, unless the steer or spayed heifer is imported for slaughter in accordance with § 93.429. The “M” mark shall be between 3 inches (7.5 cm) and 5 inches (12.5 cm) high and wide, and shall be applied to each animal's right hip, within 4 inches (10 cm) of the midline of the tailhead (that is, the top of the brand should be within 4 inches (10 cm) of the midline of the tailhead, and placed above the hook and pin bones). The brand should also be within 18 inches (45.7 cm) of the anus.
* * *
* * *
An “M” mark properly applied with a freeze brand, hot iron, or other method, and easily visible on the live animal and on the carcass before skinning. Such a mark must be between 3 inches (7.5 cm) and 5 inches (12.5 cm) high and wide, and must be applied to the upper right front shoulder of each animal; or