4. Oral Cavity - salivary glands Flashcards
what are the functions of salivary glands?
- Lubrication and binding
- Antibacterial, Enzymatic digestion
- pH regulation, Thermoregulation
- Providing urea for protein synthesis in the forestomach
where are major salivary glands located?
further away from the oral cavity compared to minor glands
do major salivary glands empty their secretion by long or short ducts?
long
what are the 3 major salivary glands
- parotid
- mandibular
- sublingual
where are minor salivary glands located?
wall of oral cavity
do minor salivary glands have long or short ducts?
short
what are the 4 minor salivary glands?
-labial
- lingual
-buccal
- palatal
what are salivary glands made up of?
secretory acini and ducts
what are acini?
several different types of secretory acinar cells and myoepithelial cells
what does serous acinus secrete?
proteins in an isotonic watery fluid
what does mucous acinus secrete?
mucin which is a lubricant
what happens structurally in a mixed serous-mucous acinus?
serous acinus forms a serous demilune around mucous acinus
explain the structure of salivary glands
- composed of lobules of exocrine tubule acinar glands that secret into a duct
- the secretory units merge into intercalated ducts that are lined by simple cuboidal epithelium and surrounded by myoepithelial cells
- secretion is mediated by contraction of myopethlial cells the surround acini
where is the parotid gland located?
paired gland located ventral to ear
what is the parotid gland vascularised by?
branches of maxillary artery and vein
what is the parotid gland innervated by?
glossopharyngeal nerve
where does the parotid gland open to in horses and dogs?
P4
horse
where does the parotid gland open in cows?
enters oral vestibule opposite upper M2
COW
where does the parotid ducts drain its fluid into?
buccal vestibule
where is the mandibular gland located?
vental to the parotid gland, caudal to the mandible bone
what is the mandibular gland vascularised by?
linguofacial artery and vein
what is the mandibular gland innervated by?
facial nerve
what does the mandibular gland share a capsule with?
sublingual gland
what secretory acinar cells does the mandibular gland have?
mixed secretory
where does the mandibular gland drain?
sublingual caruncle
where is the sublingual gland located?
mucous membrane under the tongue
the sublingual gland is composed of 2 portions called what? what species does this not apply to?
monostomatic and polystomatic
- horse
describe the difference between the monostomatic and polystomach regions of the sublingual gland
- monostomatic is more caudal with a single draining duct
- poylstomatic is more rostral with several small ducts
what does the sublingual salivary duct run parallel to?
mandibular duct
where does the sublingual gland empty?
sublingual caruncle
in the horse is the sung lingual gland monostomatic or polystomatic?
polystomatic
what do we have to remember with two components of the sublingual gland in cows?
opposite way around, monostomatic more rostral
what gland is only found in dogs?
zygomatic gland
where is the zygomatic gland located?
medial to zygomatic arch
which salivary gland has a clinical significance in the horse that it overlays the guttural pouch?
parotid gland
