Ruminant Stomach lecture

Question 1

What are the four compartments of the cow stomach?

Answer 1

• reticulum
• rumen
• omasum
• abomasum

Question 2

How many compartments does a llama have?

Answer 2

3

Question 3

Why is it advantageous to develop a compound stomach?

Answer 3

Provide an upper digestive tract capable of promoting fermentative organisms.
Microflora produce and enzyme that can digest and use low quality feed

Question 4

Where will the rumen be?

Answer 4

Left side

Question 5

Where is the reticulum?

Answer 5

Most cranial L side

Question 6

where is the omasum?

Answer 6

cranially R side and caudal to reticulum

Question 7

where is the abomasum?

Answer 7

R ventral floor caudal to xiphoid region

Question 8

What compartment increases with/development post-birth? Which one gets smaller in comparison?
Why?

Answer 8

Rumen
abomasum
Switch from milk to forage feed

Question 9

What do grooves of the rumen do?

Answer 9

Carry nutrient vessels and n.s; protection

Question 10

What do the pillars of the rumen do?

Answer 10

Compartmentalize contents

“Bones of the Rumen”=support to help contraction

Question 11

What is the significance of rumenal sacs?

Answer 11

Have different mucosal pappillae

Question 12

What are the VFAs produced in the ruman?

Answer 12

acetate
proprionate
butyrate

Question 13

Where in the rumen is there less papillae? Why?

Answer 13

Dorsal wall

gas chamber

Question 14

What are the different sacs of the rumen?

Answer 14

• cranial sac
• dorsal sac
• ventral sac
• caudodorsal sac
• caudoventral sac

Question 15

what are the different pillars of the rumen?

Answer 15

• cranial pillar
• R longitudinal pillar
• L longitudianl pillar
• caudal pillar
• dorsal coronary pillar
• ventral coronary pillar

Question 16

How does material enter the rumen?

Answer 16

rumenoreticular orifice

Question 17

What surrounds the rumenoreticular orifice?

Answer 17

rumenoreticular fold

Question 18

Where does material from the esophagus come into the rumen through?

Answer 18

caria

Question 19

How does the reticulum communicate with the omasum?

Answer 19

reticulo-omasal orifice

Question 20

What does the reticular/esophageal groove do?

Answer 20

Direct connection between esophageal cardia and the omasum.

bypasses the rumen

Question 21

Where is the reticular groove? What makes it up?

Answer 21

• R cranial wall from cardia to reticulo-omasal orifice

- 2 muscular folds that contract to form the groove

Question 22

What is the continuation of the reticular groove?

Answer 22

omasal groove

Question 23

Why is the omasal groove important?

Answer 23

Moves the milk directly to the abomasum by bypassing the rumen, reticulum, and omasum

Question 24

What does traumatic pericarditis/myocarditis entail/what causes it and where?

Answer 24

Something gets stuck in the reticulum and punctures it. Inflammation of peritoneal and pleural linings

Question 25

What is the word we should learn in anatomy for the Honeycomb compartment?

Answer 25

reticular crests

Question 26

"many plies" referes to what?

Answer 26

omasal laminae

Question 27

What structure in the omasum functions to increase absorptive surface area for water and VFAs?

Answer 27

omasal laminae

Question 28

What is the true glandular stomach?

Answer 28

abomasum

Question 29

Where is the torus pyloricus located?

Answer 29

In the abomasum

Question 30

How do things enter the abomasum?

Answer 30

Through the omasoabomasal orifice

Question 31

What is the main artery to supply the stomach?

Answer 31

celiac a.

Question 32

The splenic a. gives rise to what arteries in the stomach?

Answer 32

R ruminal a. L ruminal a. reticular a.

Question 33

L gastic a. suppllies what?

Answer 33

greater curvature of omasum and lesser curvature of the abomasum

Question 34

What is a branch off the L. gastric and what does it supply?

Answer 34

L gastroepiploic a. to other curvatures of omasum and abomasum

Question 35

What a. supplies the distal half of the abomasum?

Answer 35

hepatic a.

Question 36

What are the branches of the hepatic a. and where do the go to?

Answer 36

- R gastric a. to lesser curve of abomasum | - R gastroepiploic a. to greater curve

Question 37

What nerve is vital for life? (in regard to the stomach)

Answer 37

vagus n.

Question 38

What innervates the rumen, visceral surfaces of reticulum and omasum, and the lesser curve of abomasum? Also the celiacomesenteric G/plexus.

Answer 38

dorsal vagal trunk

Question 39

What innervates parietal surface of the stomach?

Answer 39

ventral vagal trunk

Question 40

What is the vagus responsible for?

Answer 40

``` ruminoreticular contractions omasal contractions eructation regurgitation reflex closure of reticular (gastric) groove abomasal motility and secretion ```

Question 41

Where does the greater omentum attached to on both sides?

Answer 41

descending duodenum on R side caudal part of rumen on L side ALSO on greater curve of abomasum

Question 42

What is the only communication area between sup and deep greater omentum?

Answer 42

epiploic foramen

Question 43

What is the superficial leaf of the greater omentum attached to?

Answer 43

L longitudinal groove laterally and the greater curve of abomasum cranially

Question 44

Where does the deep leaf of the greater omentum attach?

Answer 44

R longitudinal groove of rumen

Question 45

What sits in the omental bursa?

Answer 45

ventral sac of rumen

Question 46

What structures rests on the dorsal surface of the deep leaf of the greater omentum?

Answer 46

small intestines and spiral colon

Question 47

The omental bursa opens caudally and holds most of the intestines. What is this space called?

Answer 47

supraomental recess

Question 48

Where is the lesser omentum attached?

Answer 48

liver, R side of omasum, *lesser curve of abomasum*

Question 49

What are the specialized parts of the ascending colon?

Answer 49

proximal loop, spiral loop, distal loop

Question 50

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)

Answer 50

proximal loop is S shaped and has fat on the surface | distal loop is smooth

Question 51

After the abomasum, what is the route to the anus?

Answer 51

small intestines>cecum>ascending colon (proximal, spiral, distal loops), transverse colon, descending colon, rectum