Equine and porcine digestive tracts AHS1 Flashcards
What kind of GI tract do horses have?
Midgut fermenter
They have a simple stomach and a much larger caecum and ascending colon
What is distinguishing about the colour of horse viscera?
They are yellow rather than white
What are the two parts of the equine stomach?
Large non-glandular region - fundus
Glandular region - fundic
What is the name of the ridge that separates the two regions of the equine stomach?
Margo plicatus
Where is the non-glandular region in the equine stomach and how can it be identified?
It is more dorsal and it is a dirty white - less protected
Where is the glandular region in the equine stomach and how can it be identified?
More ventral and it is yellowish, covered in mucous to protect it from the stomach acids
What kind of epithelium makes up the non-glandular region in the equine stomach?
Stratified squamous epithelium
What kind of epithelium makes up the glandular region in the equine stomach?
Simple columnar epithelium
What is the name of the sphincter at the opening to the equine stomach from the oesophagus in the and what is its significance?
The oblique cardiac sphincter - it is well developed which prevents vomiting
What shape is an equine spleen?
A sickle shape
Where is the equine spleen fixed and what are found here?
At the base
This is where all the blood vessels enter
What is the main ligament associated with the spleen and why is it important?
Renosplenic/nephrosplenic ligament - from the left kidney to the spleen
Intestines can get wrapped around it and cause colic
Where is the base of the caecum associated with the peritoneum?
It is retroperitoneal
Where is the caecum located?
On the right side in the paralumbar fossa
Base is just caudal to the last rib
What is the name of the entrance of the caecum?
The ileocaecal junction
What is the name of the exit of the caecum?
The caecocolic junction
How does the caecum empty?
By contractions pushing the contents into the colon that sounds like a toilet flushing every two minutes
What is the name of the bands that are on the equine digestive tract?
Taeniae
What is the name of the smaller bands that create pockets in the caecum?
Haustra
How many taenial bands are on the caecum?
4
What is the order of the 4 parts of the equine ascending colon?
Right ventral (from caecum on the right) - left ventral - left dorsal - right dorsal
What is the name of the main flexure where the colon thins the most?
Pelvic flexure
What are all the flexures of the equine ascending colon?
In order:
The sternal flexure
The pelvic flexure
The diaphragmatic flexure
How many taeniae are on each part of the equine GI tract?
Caecum = 4 RVC = 4 LVC = 4 LDC = 1 (expands to 3) RDC = 3 Descending colon = 3
Where in rectal examination should you feel for the pelvic flexure?
Dorsal and slightly to the left
What is it when you can feel ‘bicycle tyres’ on rectal examination?
Inflated jejunoileum - torsion
What does the pig liver resemble?
Moroccan leather
What shape is the pigs ascending colon?
Spiral but more conical shaped than the flat cow one
What is the name of the pouch in the porcine stomach and which region is it in?
The diverticulum - in the expanded cardiac region
What else is different about the porcine stomach in the pyloric region?
There is a torus pyloricus - a lump/swelling in the pyloric region
Where is the pig caecum located?
On the left with the base near the left kidney
What is the name of the turns in the proximal spiral in the porcine ascending colon?
Centripetal - outer to inner
What is the name of the turns in the distal spiral in the porcine ascending colon?
Centrifugal - inner to outer
Where is the apex of the spiral porcine colon located?
On the left flank (opposite to the cow)
