Overview
Unlike in carnivores, in ruminants it is a relatively small muscle: chewing relies mainly on the masseter. In cattle the temporal fossa lies on the lateral side of the skull, caudal to the orbit and below the temporal line, which separates it from the frontal roof of the skull. The muscle passes medial to the zygomatic arch to the mandible.
Origin
Temporal fossa, bounded dorsally by the temporal line.
Insertion
Coronoid process of the mandible.
Action
Elevates the mandible and closes the mouth.
Innervation
Mandibular nerve (n. mandibularis), a branch of the trigeminal nerve (cranial nerve V).
Clinical relevance
The cornual nerve, which supplies the horn, runs along the temporal line at the dorsal border of the temporal fossa. It is blocked there with local anaesthetic for dehorning.