Large animal digestive tract AHS1

Question 1

What are the 4 main parts of the ruminant stomach?

Answer 1

Rumen
Reticulum
Omasum
Abomasum

Question 2

How is the ruminant stomach different in young animals?

Answer 2

The abomasum is a lot larger because milk digestion happens there

Question 3

Which is the most cranial part of the stomach?

Answer 3

The reticulum

Question 4

What is the reticulum associated with?

Answer 4

Right up against the diaphragm and the oesophagus

Question 5

What part of the ruminant stomach is mostly on the left side of the body?

Answer 5

The rumen

Question 6

What parts of the ruminant stomach are mostly on the right hand side?

Answer 6

The omasum (midline) and the abomasum

Question 7

What part of the stomach is the easiest to displace?

Answer 7

The abomasum

Question 8

What are the different parts of the rumen called?

Answer 8

The dorsal sac
The blind sac (caudoventral)
The ventral sac

Question 9

What is the rumens principal function?

Answer 9

Bacterial fermentation

Question 10

What divides the rumen into its different parts?

Answer 10

External grooves with corresponding internal folds and pillars

Question 11

What are the 3 main grooves on the rumen called?

Answer 11

Left longitudinal groove
Right longitudinal groove
Rumenoreticular groove/fold

Question 12

What is important about the Rumenoreticular fold?

Answer 12

It acts as a dam and is a good landmark for the reticulum when foreign bodies get stuck in it

Question 13

What does the internal surface of the rumen look like?

Answer 13

It has ruminal papillae which are more dense in the ventral part of the rumen where there is liquid instead of gas

Question 14

What does the internal surface of the reticulum look like?

Answer 14

It has a honeycomb/net like appearance

Question 15

Where is the omasum located?

Answer 15

Between the rumen and the liver

Question 16

What does the internal surface of the omasum look like?

Answer 16

It has crescentic laminae - looks like a book/chocolate orange

Question 17

What is the main function of the omasum?

Answer 17

Water absorption

Question 18

What is the main function of the abomasum?

Answer 18

Chemical digestion - true stomach

Question 19

Where is the abomasum located?

Answer 19

Mainly to the right of the rumen apart from part of the fundus

Question 20

What does the internal surface of the abomasum look like?

Answer 20

Ruggae - wiggles and folds on the inside

Question 21

What is the structure in young ruminants that allows milk to go straight into the abomasum?

Answer 21

The Rumenoreticular groove

Also known as the gastric groove

Question 22

What is the gastric groove?

Answer 22

Two spirally twisted lips of on the wall of the reticulum and the lesser curvature of the omasum

Question 23

How does the gastric groove work?

Answer 23

When the vagus nerve is stimulated the lips curl round and form a tube into the abomasum bypassing the rumen and the reticulum

Question 24

How is the vagal reflex associated with the gastric groove stimulated?

Answer 24

Feeding on milk

Question 25

What iis the main artery supplying blood to the stomach?

Answer 25

The coeliac artery

Question 26

What are the arteries (that come off the coeliac artery) that follow the lesser curvature of the abomasum?

Answer 26

The left and right gastric arteries

Question 27

What are the arteries (that come off the coeliac artery) that follow the greater curvature of the abomasum?

Answer 27

The gastroepiploic arteries

Question 28

What are found in the longitudinal grooves of the rumen?

Answer 28

The left and right ruminal arteries

Question 29

What is the main venous drainage of the ruminal stomach?

Answer 29

The veins mirror the arteries and drain via the splenic vein into the hepatic portal vein

Question 30

What is the main parasympathetic innervation of the rumen?

Answer 30

The dorsal vagus nerve

Question 31

What is the main parasympathetic innervation of the reticulum, omasum and abomasum?

Answer 31

The ventral vagus nerve

Question 32

What is the main sympathetic innervation of the ruminal stomach?

Answer 32

The nerves come from the coeliac (coeliacomesenteric) plexus and take a similar route to the arteries

Question 33

Where does the greater omentum attach to the ruminal stomach?

Answer 33

Along the right longitudinal groove and then left longitudinal groove of the rumen Over the reticulum Around the greater curvature of the abomasum Down the duodenum

Question 34

Where does the lesser omentum attach to the ruminal stomach?

Answer 34

Along the greater curvature of the omasum (because it is closely associated with the liver) Along the lesser curvature of the abomasum

Question 35

Where is the omental bursa?

Answer 35

Between the two layers of the greater omentum and goes from the ventral surface of the rumen to the duodenum on the dorsal surface

Question 36

Where is the caecum found in a ruminant?

Answer 36

On the right side and projects caudally in the right pelvic inlet

Question 37

What does the ascending colon look like in ruminants?

Answer 37

Varies between species but usually coiled in a spiral

Question 38

Where is the jejunum found in the ruminant?

Answer 38

Hangs like a frill under the colon

Question 39

What is the attachment between the ilium and the caecum called?

Answer 39

The ileocecal fold

Question 40

What are the two main surgical incisions?

Answer 40

``` Paralumbar incision Paracostal incision (more ventral) ```

Question 41

Where is the paralumbar fossa located?

Answer 41

The indent between the tuber sacrale and the tuber ischii and the costal arc

Question 42

What is a dermatome?

Answer 42

The area of skin which each spinal nerve innervates | They are names after the spinal nerves

Question 43

What kind of anaesthesia technique is used on cows?

Answer 43

Paravertebral anaesthesia - regional anaesthesia technique

Question 44

How does paravertebral anaesthesia work?

Answer 44

The needle is injected near the transverse process Some is injected into the dorsal ramus The needle then goes through the intertransverse ligament The rest is then injected into the ventral ramus