Carnivore GI System Flashcards
What are the 4 tunics of the GI tract?
- Mucosa
- Submucosa
- Muscularis
- Serosa or adventitia
What are the three parts of the mucosa?
Epithelium
Lamina propria
Muscularis mucosa
What is Meissner’s nerve plexus?
Also known as Submucosal nerve plexus
Contains sympathetic and parasympathetic fibers.
What is Myenteric nerve plexus?
Also known as Auerbach’s plexus
Parasympathetic terminal ganglia and autonomic fibers between muscle layers.
What are the two layers of the tunica muscularis (in the typical gut section)?
- Inner circular muscle layer (forms sphincters)
- Outer longitudinal muscle layer (forms longitudinal bands)
Adventitia
ill-defined layer of connective tissue blending with surrounding connective tissue
Serosa
Thin connective tissue layer covered by mesothelium.
A simple squamous epithelium aka the visceral peritoneum.
Philtrum
Median cleft of the upper lip in carnivores and small ruminants.
Palatine rugae
A series of transverse ridges on the anterior part of the palatal mucosa of the hard palate.
Dental pad
Present in ruminants. Located in the rostral part of the hard palate. Replaces the upper incisors.
Incisive papilla
Small median swelling behind the incisor teeth. Incisive ducts to the vomeronasal gland.
Sublingual caruncles
Mucosal elevations on the floor of the oral cavity under the tongue and just caudal to the incisors.
Lingual frenulum
Central fold of mucous membrane connecting the floor of the oral cavity and the ventral surface of the tongue.
What cranial nerve innervates the lips?
CN 7, facial nerve.
What are the four muscles of mastication?
- Temporalis
- Masseter
- Pterygoideus medialis
- Pterygoideus lateralis
What are the characteristics of Filiform papillae? Is it mechanical, gustatory, or both?
Mechanical (functions to direct food caudally). Most numerous type of papillae.
Forms a velvety covering of the tongue.
Found on the dorsal surface of the rostral ⅔ of the tongue.
Apical processes are keratinized and point caudally.
Large and rough in cats and cattle; act as bristles for grooming.
What are the characteristics of Conical papillae? Is it mechanical, gustatory, or both?
Mechanical.
Located on the root of the tongue & cheek’s inner surface.
Large, keratinized epithelium and a large connective tissue core.
Not found in horses.
What are the characteristics of Lenticular papillae? Is it mechanical, gustatory, or both?
Mechanical.
Found in ruminants.
Large and grossly visible, lentil shaped. Keratinized.
Found on the dorsal prominence of the tongue.
What are the characteristics of Fungiform papillae? Is it mechanical, gustatory, or both?
Gustatory and possibly mechanical.
Scattered on the rostral dorsal surface of the tongue.
May be keratinized in herbivores.
What are the characteristics of Circumvallate papillae? Is it mechanical, gustatory, or both?
Gustatory.
Arranged in a “V” at the rostral border of the root of the tongue.
Each papillae is surrounded by a depression called a moat.
Taste buds are on the lateral surface and open in the moat.
Pigs/horses have 1 pair.
Carnivores have 2-3 pairs.
Ruminants have many pairs.
What are the characteristics of Foliate papillae? Is it mechanical, gustatory, or both?
Gustatory.
Found in a row at the lateral margin of the tongue.
Leaf-like and separated by furrows.
Found in pigs, horses, carnivores, and rabbits.
What is the difference between the parotid salivary gland secretions and the mandibular salivary gland secretions?
Parotid salivary gland produces serous secretion.
Mandibular salivary gland produces mixed mucous and serous secretion.
Is the esophagus dorsal or ventral to the trachea?
Dorsal to the trachea.
Which parts of the GI tract have submucosal glands?
Only found in the esophagus and duodenum.
Which species of animals have striated muscle only in the proximal portion of the esophagus?
Cats, pigs, and horses.
Where does the greater omentum attach to the stomach? The lesser omentum?
Greater omentum attaches to the greater curvature.
Lesser omentum attaches to the lesser curvature.
Cardia (of the stomach)
Opening or part of the stomach around the opening.
Closest to the heart.
Not to be confused with the cardiac gland region
Fundus (of the stomach)
Blind, expanded portion of the stomach
Body (of the stomach)
Largest part of the stomach
Pylorus (of the stomach)
Distal opening of the stomach.
Surrounded by a strong band of circular muscle (aka pyloric sphincter).