Ruminant GIT

Question 1

Where is the ruminant stomach in the cow?

Answer 1

Left abdomen, takes up all of left and part of right abdomen

Question 2

What is the largest section of the ruminant stomach?

Answer 2

Rumen

Question 3

Which three parts of the ruminant stomach make up the forestomach?

Answer 3

Reticulum, rumen, omasum

Question 4

What four sacs make up the rumen?

Answer 4

Dorsal sac, caudodorsal sac, caudoventral sac, ventral sac

Question 5

How is the reticulum separated from the rumen?

Answer 5

The ruminoreticular fold

Question 6

What is the reticular groove?

Answer 6

A channel present in calves, goes from esophagus right to omasum/abomasus and bypasses the reticulum/rumen, formation is stimulated by suckling and CuSO4

Question 7

How is the rumen divided into sacs?

Answer 7

With pillars, cranial/caudal pillar divide rumen into dorsal/ventral sacs

Question 8

Where is the atrium ruminis?

Answer 8

The very first sac of the dorsal rumen, where digesta from reticulum enters the rumen

Question 9

Which section of the ruminant stomach has a honeycombed surface?

Answer 9

Reticulum

Question 10

Which section of the ruminant stomach has a papillated surface?

Answer 10

Rumen

Question 11

What layers is the ruminant stomach comprised of?

Answer 11

Mucosa, two muscle layers (Thick inner layer around long axis, thin outer layer running craniocaudally), serosa

Question 12

Where is the omasum positioned in comparison to the midline?

Answer 12

Slightly to the right of the midline

Question 13

What is the difference in appearance between the cattle omasum and the sheep/goat omasum?

Answer 13

Cattle: More rounded

Sheep/goat: More bean-shaped

Question 14

Describe the omasum.

Answer 14

Has tissue folds with variably-sized papilla, meant to squeeze liquid out of/filter digesta and absorb water

Question 15

Where does the abomasum lay in the abdomen?

Answer 15

On the right abdominal floor

Question 16

What are the parts of the abomasum?

Answer 16

Fundus, body, pylorus

Question 17

What is unique about the abomasum?

Answer 17

Glandular, has large mucosal folds, torus narrows pylorus, has a double layer of muscle

Question 18

What are the three types of glands of the abomasum?

Answer 18

Cardiac glands, gastric glands, pyloric glands

Question 19

Damage to which branch of the vagal nerve is less serious?

Answer 19

Ventral vagal trunk, can have no effects to paralysis of forestomach (Dorsal trunk results in almost entire paralysis of rumen, if both damaged, abomasum can still contract somewhat)

Question 20

Where is the ruminant stomach attached to the body?

Answer 20

The dorsal sac of the rumen is attached to the abdominal wall

Question 21

What is the largest chamber of the ruminant stomach at birth?

Answer 21

Abomasum

Question 22

How is the duodenum placed in the ruminant body?

Answer 22

Rises dorsally from abomasum, descends to pelvis with flexure, then ascending duodenum

Question 23

What does the jejunum look like in the ruminant?

Answer 23

Short coils, free margin of common mesentery, position variable depending on gut distension

Question 24

What does the ileum look like in the ruminant?

Answer 24

Short, attached to cecum via the ileocecal fold

Question 25

What is the widest part of the ruminant intestine?

Answer 25

Cecum

Question 26

Which two species have a spiral colon?

Answer 26

Cow (1.5-2 turns) and sheep (3-4 turns)

Question 27

What are the two sides of the spiral colon called?

Answer 27

Centripetal (Inner) and centrifugal (Outer)

Question 28

What are the four lobes of the ruminant liver?

Answer 28

Left lobe, quadrate lobe, right lobe, caudate lobe

Question 29

How is the ruminant liver suspended in the abdomen?

Answer 29

Triangular ligaments, round ligament, lesser omentum, surrounding organs

Question 30

Describe the ruminant pancreas.

Answer 30

Attached to the liver, left lobe crosses dorsal to rumen and ventral to liver, right lobe runs with descending duodenal mesentery, cattle: one pancreatic duct that enters duodenum after the bile duct, small ruminants: pancreatic duct enters with bile duct

Question 31

Describe the stomach in the calf as compared to an adult cow.

Answer 31

Large abomasum with full glandular function in a few days, small ruminoreticulum and abomasum, fore-stomach walls are thin with papillae

Question 32

How does the calf stomach develop?

Answer 32

Solid diet starts to be incorporated around 2-3 weeks, rumen surpasses size of abomasum around 8 weeks, twice the size of abomasum around 12 weeks, development continues with continuous stimulation from forage/fermentation/stretching of stomach, liver starts on midline then moves right as the stomach grows

Question 33

What are the phases of development of the calf?

Answer 33

Milk diet: 0-2 or 3 weeks Mixed diet (Transitional adaption to solid food): 3-8 weeks Solid diet: 8 weeks, anatomy/physiology of an adult