Hyoid bone of animals
Hyoid bone of Ox
Hyoid bone of Ox is situated between the vertical parts of the rami of the mandible and extends obliquely downward and forward from the temporal above to the root of the tongue below. It consists of a body, a lingual (glossal) process and four pairs of cornua (stylohyoid, epihyoid, keratohyoid and thyrohyoid).
- The body or basi-hyoid is short rod of bone placed transversely. The anterior border, in its middle, carries the short blunt glossal process, which is embedded in the root of the tongue.
- The body is attached to the thyroid cornua of the thyro-hyoid by bars of cartilage on the postero -lateral aspects.
- The thyroid cornua extend backward and upward from the body and are attached to the anterior cornua of the thyroid cartilage of the larynx.
- The ketato-hyoids (small cornua) are directed upward and forward and articulate by the lower ends by concave facets with the cartilage uniting the body and thyroid cornua. Their upper ends are attached to the of lower ends of the middle cornua or epihyoids by short bars of cartilage.
- The epihyoid is a small curved rod attached to the small cornua below and the great cornu or stylo-hyoid above which is largest piece.
- The great cornu is directed upward and backward. Its lower end is attached to the upper end of the epihyoid. Its upper end resembles a human foot and has a heel-like part the muscular angle for muscular attachment and a toe-like part-the articular angle, which is connected by a short rod of cartilage to the hyoid process of the petrous temporal.
Hyoid bone of Horse
- The lingual process (glosso-hyoid) is longer with its free end pointed.
- The thyro-hyoid are fused with the body.
- The body of thro-hyoids and glosso-hyoid are fused and resemble spur or fork.
- The epihyoid is fused with the lower end of the stylo-hyoid.
Hyoid bone of Dog
- The glosso-hyoid is absent.
- The epihyoid is longer than the stylo-hyoid.
- The stylo-hyoid is bent and twisted.
- The thyro-hyoid is permanently attached to the body by cartilage.
Hyoid bone of Fowl
- It is composed of seven bony segments-three median and two lateral processes.
- The anterior median segment is the entoglossal and is embedded in the tongue.
- It articulates behind with the second or basi-hyoid.
- The basi-hyoid (body) is connected behind to the third segment of uro-hyoid at its middle and to the lateral processes by a bar of cartilage at either end.
- The uro-hyoid is partly bony and partly cartilaginous.
- Each lateral process consists of an anterior basi-branchial and a posterior cerato-branchial connected by cartilage. The lateral processes extend posteriorly upwards and towards the occipital bone.
