Skull Flashcards
What can impact the shape of the head?
age, breed, and gender
In what species is sexual dimorphism seen best in (change in size due to sex)?
Ox
In the ox, do males or females have larger skulls?
males
Generally, why is the skull larger in large animal (and no, it is not because they are bigger)?
because they are herbivores, and they need more surface area for muscle attachment and more volume to house teeth
True or False: the ox has no upper incisors, but has upper canines.
False: the ox has no upper incisors or canines
What is the temporal line in the ox?
it outlines the temporal fossa (is confined to the frontal bone)
When is the cornual process present and where is it located?
it is only present in horned animals and it is located on the frontal bone
What is the purpose of the facial tuberosity?
it functions as an area of muscle attachment
Where is the facial tuberosity located in the ox?
on the maxilla
What is the function of the facial crest in the horse?
it is a site of muscle attachment
Why is the nasoincisive notch clinically relevant in the horse?
it is used to find the infraorbital foramen for nerve blocking
In what species is the external lacrimal fossa present in?
the sheep
If horned, where would the cornual process be located in the sheep/goat?
closer to the orbit due to a smaller frontal bone
What are the foramina on the skull of the dog (6)?
optic canal, orbital fissure, rostral alar, round foramen, caudal alar, oval foramen
What goes through the optic canal in the dog?
the optic nerve (CN II)
What goes through the orbital fissure in the dog?
the oculomotor nerve (CNIII), the trochlear nerve (CN IV), the opthalmic branch of the trigeminal (V1), the abducent nerve CN VI)
What goes through the rostral alar foramen in the dog?
the maxillary branch of the trigeminal (V2), and the maxillary artery
What goes through the round foramen in the dog?
the maxillary branch of the trigeminal nerve (V2)
What goes through the caudal alar foramen in the dog?
the maxillary artery
What goes through the oval foramen in the dog?
the mandibular branch of the trigeminal (V3)
What are the foramina on the caudal portion of the skull in the ruminant?
ethmoid foramen, optic canal, foramen orbitorotundum, oval foramen, tympano-occipital, stylomastoid
What goes through the optic canal in the ruminant?
the optic nerve (CN II)
What species is the foramen orbitorotundum in?
ruminants and the pig
What forms the foramen orbitorotundum?
the orbital fissure and round foramen
What foes through the foramen orbitorotundum?
the oculomotor (CN III), the trochlear (CN IV), the opthalmic and maxillary branches of the trigeminal (V1 and V2), the abducent (CN VI)
What goes through the oval foramen in the ruminant?
the mandibular branch of the trigeminal nerve
What goes through the tympano-occipital fissure in the ruminant?
the glossopharyngeal (CN IX), the vagus (CN X), and the accessory (CN XI)
What are the foramina on the caudal portion of the skull in the horse?
foramen lacerum, optic canal, orbital fissure, rostral alar, and caudal alar
What species have the foramen lacerum?
the horse and pig
What is the foramen lacerum made up of?
the jugular foramen, the oval foramen and carotid foramen
What goes through the foramen lacerum in the horse?
V2, the internal carotid nerve and artery, IX, X, XI
What goes through the optic canal in the horse?
the optic nerve (CN II)
What goes through the orbital fissure in the horse?
the oculomotor nerve (CN III), the trochlear nerve (CN IV), the opthalmic branch of the trigeminal (V1), and the abducent nerve (VI)
What goes through the rostral alar foramen in the horse?
the maxillary branch of the trigeminal and the maxillary artery
What goes through caudal alar foramen in the horse?
the maxillary artery
