White line

The connection between the epidermal lamellae of the hoof wall and the sole is formed by a soft type of horn (terminal horn) produced by the terminal papillae that extend from the end of the dermal lamellae. This connection is called white line. At the bottom of the hoof the white line is visible as a yellowish line between the hoof wall and the sole perimeter. The white line acts as a hinge between hoof wall and sole to facilitate the hoof mechanism.