keratinized oral mucosa

hint: what contacts food and friction?

dental pad

dorsal surface of tongue

hard palate

cheek

Vallate / Circumvallate

fungiform

foliate

most common type

slender conical projections

bristles, can be rougher in some species

least numerous type

short broad CT stalk with nerves

taste buds along sides

does not protrude above surface - surrounded by moat

back of tongue

mushroom shaped

CT core
rise higer than filiform 

flat topped / square shape

deep clefts between

important in lagomorphs (rabbit)

lots of taste buds

encapsulated by thin CT

light stain with darker sensory cells

taste pore: break in epithelium

should just be epithelium and lamina propria

keratinizing stratified squamous epithelium

lamina propria shouldn't take up too much - hyperplasia

hard with bone, soft without

oral surface: stratified squamous epithelium

respiratory nasal surface: cilitated columnar

outer covering of tooth

crowns

not visible in slides - lost in processing

major bulk of the tooth

softer than enamel

bone like substance

covers tooth root - does not protrude beyond gum line

enamel is made up until teeth erupt

after eruption ameloblasts die

enamel cannot be replaced once damaged

rodent: continually produce enamel and must wear teeth down by chewing. root and crown grow simultaneously and constantly throughout life

horse: enamel and dentin layers are combined, increasing strength and decreasing wear rate

further from the buccal cavity, have long ducts

parotid

mandibular

sublingual

zygomatic (carnivore)

molar (carnivore)

labial

lingual

buccal

palatine

compund tubuloalveolar cells

can be mucous, serous or mixed

innermost layer (toward lumen)

-Muscularis mucosa

Loose CT

Blood vessels

Lymphatics

Lymphocytes

Plasma cells

meissner's plexus

fibrous connective tissue

adipose tissue (or not)

glands (or not)

GALT

vessels

2 layers of smooth muscle, inner circular and outer longitudinal

(esophagus can be smooth, skeletal or mixed muscle)

vessels and myenteric plexus

-Single layer of mesothelium

-Scant fibrous CT

-Blood & lymphatic vessels

Distal colon & Rectum

stratified squamous epithelium

can be keratinized or not

muscularis mucosa is discontinous and can be absent cranially (dog and pig)

contains glands

do not extend into caudal half

keratinized

absorption

no glands

Some contain smooth muscle

T. Mucosa:

  Intersecting folds (laminae)

    within upper segment of

    1◦ fold(aka. long fold)

T. mucosa:

T. mucosa

Leaves:

Glands: cardiac, fundic, pyloric

  tubular structures that connect to invaginations of epithelium from surface

in cardia and pylorus

Chief cells

-  Cover the surface and line the gastric pits

  -  Columnar cells with basally located oval nuclei and abundant apical cytoplasm containing tiny mucous droplets. 

Mucous neck cells:

  -Found at the neck of the gland

  - Smaller than surface mucous cells & contain less amount of mucin in the cytoplasm and round nucleus

- Found between the mucous neck cells and chief cells

  - Large, polygonal cells with eosinophilic cytoplasm and central round nuclei

  - SECRETE:  HCl, gastric intrinsic factor 

- Located deeper in the fundic glands

  - Eosinophilic apical cytoplasm (zymogen granules) and basophilic basal cytoplasm (rER) 

  - SECRETE:  pepsinogen, trypsinogen, renin (ruminant), gastric intrinsic factor (some species)

only present in sm intestine

lionger and slender in carnivores

shorter and thicker in ruminants

microvilli increase surface area

“Peyer’s patches”

"gizzard"

avian muscular stomach

contains stones

diverticulum of esophagus

(a.k.a. pellicle)

liver

2-5% of body weight

Route of entry for blood borne organisms

     Intrahepatic components

Extrahepatic components

reptile liver

immune surveillance

store bile

concentrate it 

epithelium produces mucus

Also islets of endocrine tissue