Ruminant Stomach lecture Flashcards
What are the four compartments of the cow stomach?
- reticulum
- rumen
- omasum
- abomasum
How many compartments does a llama have?
3
Why is it advantageous to develop a compound stomach?
Provide an upper digestive tract capable of promoting fermentative organisms.
Microflora produce and enzyme that can digest and use low quality feed
Where will the rumen be?
Left side
Where is the reticulum?
Most cranial L side
where is the omasum?
cranially R side and caudal to reticulum
where is the abomasum?
R ventral floor caudal to xiphoid region
What compartment increases with/development post-birth? Which one gets smaller in comparison?
Why?
Rumen
abomasum
Switch from milk to forage feed
What do grooves of the rumen do?
Carry nutrient vessels and n.s; protection
What do the pillars of the rumen do?
Compartmentalize contents
“Bones of the Rumen”=support to help contraction
What is the significance of rumenal sacs?
Have different mucosal pappillae
What are the VFAs produced in the ruman?
acetate
proprionate
butyrate
Where in the rumen is there less papillae? Why?
Dorsal wall
gas chamber
What are the different sacs of the rumen?
- cranial sac
- dorsal sac
- ventral sac
- caudodorsal sac
- caudoventral sac
what are the different pillars of the rumen?
- cranial pillar
- R longitudinal pillar
- L longitudianl pillar
- caudal pillar
- dorsal coronary pillar
- ventral coronary pillar
How does material enter the rumen?
rumenoreticular orifice
What surrounds the rumenoreticular orifice?
rumenoreticular fold
Where does material from the esophagus come into the rumen through?
caria
How does the reticulum communicate with the omasum?
reticulo-omasal orifice
What does the reticular/esophageal groove do?
Direct connection between esophageal cardia and the omasum.
bypasses the rumen
Where is the reticular groove? What makes it up?
- R cranial wall from cardia to reticulo-omasal orifice
- 2 muscular folds that contract to form the groove
What is the continuation of the reticular groove?
omasal groove
Why is the omasal groove important?
Moves the milk directly to the abomasum by bypassing the rumen, reticulum, and omasum
What does traumatic pericarditis/myocarditis entail/what causes it and where?
Something gets stuck in the reticulum and punctures it. Inflammation of peritoneal and pleural linings
What is the word we should learn in anatomy for the Honeycomb compartment?
reticular crests
“many plies” referes to what?
omasal laminae
What structure in the omasum functions to increase absorptive surface area for water and VFAs?
omasal laminae
What is the true glandular stomach?
abomasum
Where is the torus pyloricus located?
In the abomasum
How do things enter the abomasum?
Through the omasoabomasal orifice
What is the main artery to supply the stomach?
celiac a.
The splenic a. gives rise to what arteries in the stomach?
R ruminal a.
L ruminal a.
reticular a.
L gastic a. suppllies what?
greater curvature of omasum and lesser curvature of the abomasum
What is a branch off the L. gastric and what does it supply?
L gastroepiploic a. to other curvatures of omasum and abomasum
What a. supplies the distal half of the abomasum?
hepatic a.
What are the branches of the hepatic a. and where do the go to?
- R gastric a. to lesser curve of abomasum
- R gastroepiploic a. to greater curve
What nerve is vital for life? (in regard to the stomach)
vagus n.
What innervates the rumen, visceral surfaces of reticulum and omasum, and the lesser curve of abomasum? Also the celiacomesenteric G/plexus.
dorsal vagal trunk
What innervates parietal surface of the stomach?
ventral vagal trunk
What is the vagus responsible for?
ruminoreticular contractions omasal contractions eructation regurgitation reflex closure of reticular (gastric) groove abomasal motility and secretion
Where does the greater omentum attached to on both sides?
descending duodenum on R side
caudal part of rumen on L side
ALSO on greater curve of abomasum
What is the only communication area between sup and deep greater omentum?
epiploic foramen
What is the superficial leaf of the greater omentum attached to?
L longitudinal groove laterally and the greater curve of abomasum cranially
Where does the deep leaf of the greater omentum attach?
R longitudinal groove of rumen
What sits in the omental bursa?
ventral sac of rumen
What structures rests on the dorsal surface of the deep leaf of the greater omentum?
small intestines and spiral colon
The omental bursa opens caudally and holds most of the intestines. What is this space called?
supraomental recess
Where is the lesser omentum attached?
liver, R side of omasum, lesser curve of abomasum
What are the specialized parts of the ascending colon?
proximal loop, spiral loop, distal loop
What is the difference in gross appearance from the proximal and distal loops of the ascending colon? (note that they run right next to each other)
proximal loop is S shaped and has fat on the surface
distal loop is smooth
After the abomasum, what is the route to the anus?
small intestines>cecum>ascending colon (proximal, spiral, distal loops), transverse colon, descending colon, rectum
