Lecture 31: Abdomen IV Equine and Ruminant Foregut

Question 1

what structure divides glandular from nonglandular region of equine stomach

Answer 1

margo plicatus

Question 2

left side of ruminant abdominal cavity is dominated by what structure

Answer 2

volume of rumen

Question 3

structures located on right side of ruminant abdominal cavity (3)

Answer 3

-midgut organs
-hindgut organs
-dorsal mesentery

Question 4

flow of ingesta through ruminant stomach: general

Answer 4

esophagus –> rumen and reticulum –> omasum –> abomasum –> duodenum

Question 5

forestomach/proventriculus components

Answer 5

rumen
reticulum
omasum

Question 6

is ruminant forestomach glandular or nonglandular

Answer 6

nonglandular

Question 7

what is the glandular region of the ruminant stomach

Answer 7

abomasum

Question 8

3 glands/regions of abomasum

Answer 8

cardia
fundus
pylorus

Question 9

function of rumen and reticulum

Answer 9

reduce tough ingesta by processes of microbial fermentation (that can’t be broken down with mammalian enzymes)

Question 10

flow of ingesta through ruminant stomach: specific

Answer 10

Esophageal opening located dorsal to reticulum and enters into atrium ruminis, goes through ruminoreticular fold, through reticular groove, into reticulum, to abomasum

Question 11

relative locations of reticulum, diaphragm and heart

Answer 11

reticulum is just caudal to thoracic cavity containing heart and diaphragm

Question 12

microanatomy of rumen and reticulum: 5 layers

Answer 12

-stratified squamous epithelium
-lamina propria
-muscularis mucosa
-submucosa
-muscularis interna

Question 13

what causes honeycomb structure of reticulum

Answer 13

mucosal ridges outlining cells

Question 14

rumen microanatomy (2)

Answer 14

stratified squamous epithelium
papillated ruminal mucosa

Question 15

reticulum microanatomy (3)

Answer 15

stratified squamous epithelium
honeycomb
mucosal lining is cornified/keratinized

Question 16

omasum contractions process

Answer 16

squeeze ingesta from omasal canal into recesses between the laminae –> mass contraction (squeeze fluid from material), some absorption continued

Question 17

which ruminant stomach region is ill suited for milk digestion

Answer 17

rumen

Question 18

reiculo-omasal opening in newborns

Answer 18

-rumen in nonfunctional
-reticular fold/groove shunts milk from esophagus to abomasum

Question 19

entrance to abomasum is called

Answer 19

omasoabomasal orifice

Question 20

abomasum exit points: from ________ to __________

Answer 20

pylorus to duodenum

Question 21

what structure controls the release of products into duodenum

Answer 21

torus pyloricus

Question 22

development of lesser omentum

Answer 22

-from ventral mesogastrium
tissue running from ventral or lesser curvature of stomach

Question 23

what artery supplies ruminant foregut

Answer 23

celiac

Question 24

innervation of ruminant foregut

Answer 24

vagal trunks

Question 25

what is the anatomical transition between foregut and midgut

Answer 25

duodenum

Question 26

1st part of the duodenum is what end of the developing foregut

Answer 26

caudal

Question 27

what 3 structures share a duct system for delivery of bile and pancreatic juices to duodenum

Answer 27

liver
gallbladder
pancreas

Question 28

1st part of duodenum receives (2)

Answer 28

bile
pancreatic juices

Question 29

where does bile duct travel

Answer 29

dorsally along 1st part of duodenum

Question 30

how/where does duodenum receive bile

Answer 30

from liver/gallbladder via common bile duct

Question 31

how/where does duodenum receive pancreatic juices

Answer 31

from pancreas via main and accessory pancreatic ducts

Question 32

what happens between common bile duct and main pancreatic duct

Answer 32

meet and drain into duodenum at major duodenal papilla

Question 33

what allows juices to enter duodenal papilla (gastric emptying)

Answer 33

Sphincter of papilla and contraction of muscularis externa

Question 34

what do pyloric glands release (2)

Answer 34

-gastrin
-mucous

Question 35

gastrin

Answer 35

peptide hormone that stimulates parietal cells and aids in gastric motility

Question 36

characteristic of duodenal mucosa

Answer 36

prominent villi and crypts of intestinal glands

Question 37

brunner’s glands: definition, function, location

Answer 37

-secrete alkaline mucous that lowers acidity in 1st part of duodenum (raise pH for pancreatic enzyme function and protect from stomach acids)
-only present in proximal part of duodenum
-drain in Crypts of Lieberkuln which drain between villi

Question 38

what lines surface of mucosa: 1st part of duodenum

Answer 38

villi

Question 39

where are brunner’s glands found (specific)

Answer 39

submucosa of proximal portion of duodenum

Question 40

crypts of Lieberkuln: definition, location

Answer 40

-in between villi and extend to muscularis mucosa of duodenum
-short tubular glands