Dorsal longitudinal groove

In Bulls, on the dorsal surface (Facies dorsalis) of the cannon bone that results of the fusion of the metacarpal bones III and IV, a dorsal longitudinal groove (Sulcus longitudinalis dorsalis) on the suture of the two bones. This groove ends on each of its extremities to a proximal and distal bony metacarpal/metatarsal canal (Canales metacarpi/metatarsi proximalis & distalis) that crosses the bone from side to side.

The palmar surface (Facies palmaris) of the cannon bone has a weaker palmar/plantar longitudinal groove (Sulcus longitudinalis palmaris/plantaris) that also goes from one metacarpal canal to the other.