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==Structure==

==Structure==

 

The skull is made of many small bones, most of which are paired. Cartilage or fibrous tissue separates the bones of the skull in the young animal and once growth has ceased, the sutures begin to ossify.

*The skull is made of many smaller bones

 

*Most of the skull bones are paired

 

*Cartilage or fibrous tissue separates the bones of the skull in the young animal

 

*Once growth has ceased, the sutures begin to ossify

 

==Function==

==Function==

 

The skull has various functions including protection of brain, support of the facial muscles by providing origin and insertion sites, development of foramen to provide entry and exit places for the vasculature and nervous system and a defense function.

*Protection of brain

 

*Support facial muscles by providing origin and insertion sites

 

*Foramen provide entry and exit places for the vasculature and nervous system

 

 

==Bones of the Skull==

==Bones of the Skull==

[[Image:Pig skull dorsal.jpg|thumb|right|150px|Pig skull (nuchal crest, nasal bone, frontal bone, pareital bone, zygomatic process of the temporal bone and coronoid process of the mandible labelled) - Copyright nabrown RVC]]

[[Image:Pig skull dorsal.jpg|thumb|right|150px|Pig skull (nuchal crest, nasal bone, frontal bone, pareital bone, zygomatic process of the temporal bone and coronoid process of the mandible labelled) - Copyright nabrown RVC]]

'''Occipital Bone (os occipitale)'''

===Occipital Bone (os occipitale)===

*Forms the nuchal wall

The occipital bone forms the nuchal wall and the foramen magnum. The pars basilaris element is the caudal base of the cranium, although rostral to foramen magnum and joined by a cartilagenous suture to basisphenoid bone. It has muscular tubercules on ventral surface where the flexors of the head and neck attach and a caudocranial fossa encloses the pons and medulla oblongata. The  squamous part (pars squamosa) is dorsal to lateral parts and occipital condyles. A nuchal crest is present and is easily palpable. The nuchal crest is often used as a landmark for collection of cerebrospinal fluid (CSF). There are also external occipital protuberances present which provide muscle attachment sites for the nuchal ligament. The lateral parts (partes laterales) form the borders of foramen magnum. Occipital condyles are present which articulate with the atlas to form the atlanto-occipital joint. Paracondylar process provide muscle attachment sights for muscles of the head. The hypoglossal canal is also within this structure.

*Forms the foramen magnum

*Basilar part (pars basilaris)

**Caudal base of the cranium

===Sphenoid Bone (os sphenoidale)===

**Rostral to foramen magnum

**Joined by cartilagenous suture to basisphenoid bone

**Muscular tubercules on ventral surface where the flexors of the head and neck attach

**Caudal cranial fossa enclose the pons and medulla oblongata

 

*Squamous part (pars squamosa)

**Dorsal to lateral parts and occipital condyles

**Nuchal crest present

***Easily palpable

***Landmark for collection of cerebrospinal fluid (CSF)

**External occipital protuberances present which provide muscle attachment sites for the nuchal ligament

 

*Lateral parts (partes laterales)

**Lateral borders of foramen magnum

**Occipital condyles present which articulate with the atlas to form the atlanto-occipital joint

**Paracondylar process present which provides muscle attachment sights for muscles of the head

 

'''Sphenoid Bone (os sphenoidale)'''

[[Image:Pig skull ventral view.jpg|thumb|right|150px|Ventral view pig skull (vomer, occipital condyle, sphenoid, pterygoid bone, hamulus labelled)- Copyright nabrown RVC]]

[[Image:Pig skull ventral view.jpg|thumb|right|150px|Ventral view pig skull (vomer, occipital condyle, sphenoid, pterygoid bone, hamulus labelled)- Copyright nabrown RVC]]

*Forms the base of the neurocranium

*Forms the base of the neurocranium