Gastrointestinal Physiology

Question 1

What is the percentage of the foregut?

Answer 1

37%

Question 2

What organs are included in the foregut?

Answer 2

Stomach and Small Intestine

Question 3

What is the percentage of the hindgut?

Answer 3

63%

Question 4

What organs are included in the hindgut?

Answer 4

cecum, large colon, and small colon

Question 5

what is the purpose of the ENS?

Answer 5

constantly monitors GIT function; brain of the gut

Question 6

what processes are occurring in the ENS?

Answer 6

synaptic transmission, paracrine signaling, hormonal signaling

Question 7

what are the 3 main salivary glands?

Answer 7

parotid, mandibular, and sublingual

Question 8

saliva is what percent water?

Answer 8

99%

Question 9

how much saliva do horses secrete daily?

Answer 9

10-12 L with. a 8.6-9.1 pH

Question 10

saliva secretion is stimulated by what?

Answer 10

mastication and intake

Question 11

do horses have digestive enzymes such as amylase?

Answer 11

not really

Question 12

do horses chew thoroughly compared to ruminants?

Answer 12

no

Question 13

what are the 3 phases of the chewing cycle?

Answer 13

opening, closing, and power stroke

Question 14

chewing increases the surface area which allows for what to occur?

Answer 14

more digestive access

Question 15

what are the 2 portions of the esophagus and their fractions?

Answer 15

proximal is 2/3 striated and distal is 1/3 smooth

Question 16

swallowing is induced by the presence of what?

Answer 16

food!

Question 17

what is the transit time of the esophagus

Answer 17

4-10 seconds

Question 18

why can’t horses vomit

Answer 18

no proven reason; oblique angle of connection between esophagus and stomach; esophagus structure; poor retching action, etc.

Question 19

is the stomach small or large comparitive to the size of the horse?

Answer 19

small and fixed

Question 20

what are the 2 main mucosal divisions of the stomach? and what divides them?

Answer 20

glandular and nonglandular; marco plicatus divides

Question 21

the glandular region of the stomach is also known as what?

Answer 21

fundic

Question 22

what cells are located in the fundic (glandular) region of the stomach? what do they do?

Answer 22

parietal (HCl)
zymogen/chief (pepsin, lipase)
ECL- histamine
D-somatostatin

Question 23

what cells are present in the pyloric region of the stomach and what do they do?enzy

Answer 23

G- gastrin
D- somatostatin
goblet- mucus

Question 24

enzymatic activity occurs where?

Answer 24

glandular fundus

Question 25

where does fermentative action occur in the stomach?

Answer 25

saccus caecus due to lactic acid bacteria that produces VFAs that go through the tract and get digested

Question 26

what likes to sit in the saccus caecus?

Answer 26

low density fiber mat

Question 27

what occurs in the saccus caecus?

Answer 27

fermentation!!

Question 28

what are the 3 major regions of the small intestine (in order)

Answer 28

duodenum, ileum, jujenum

Question 29

what is the meeting point of the bile duct and the pancreatic duct in the small intestine?

Answer 29

duodenal diverticulum

Question 30

what is in the small intestine that aids in the tract (tell what it aids in?)

Answer 30

surface epithelium (absorption) goblet (mucus) endteroendocrine (communicates with the ENS) paneth (immunity) undifferentiated (?)

Question 31

what organs do horses not have?

Answer 31

gallbladder

Question 32

where do liver and pancreas secretions flow w/o the gallbladder?

Answer 32

sphincter oddi (continuous)

Question 33

bile salts help to emulsify what in horses?

Answer 33

fat

Question 34

compare the pancreatic activity of horses to other species?

Answer 34

lower

Question 35

the brush border in the small intestines contains what?

Answer 35

dissaccharides

Question 36

explain protein digestion/absorption in the small intestine?

Answer 36

11-30% of whole tract apparent N digestion

Question 37

explain fat digestion/absorption in the small intestine?

Answer 37

90% digested, can easily overwhelm the system

Question 38

explain carb digestion/absorption in the small intestine?

Answer 38

readily increases in transporter expression but less than other types of species (cats, dogs, etc.)

Question 39

what are the 3 parts of the cecum?

Answer 39

base, body, apex

Question 40

does the cecum contain enzymes or villi?

Answer 40

no

Question 41

where is the cecum located?

Answer 41

upper right flank

Question 42

the colon direction!

Answer 42

right ventral (sternal flexure) left ventral (pelvic flexure) left dorsal (diaphragmatic flexure) right dorsal

Question 43

what occurs in the small/descending colon

Answer 43

fecal ball formation

Question 44

what to think of when you think of cecum and colon?

Answer 44

fermentation!

Question 45

what is the product of the cecum and colon fermentation?

Answer 45

VFAs

Question 46

is there a more diverse bacterial and microorganism population in the cecum or colon?

Answer 46

colon

Question 47

what are the commonly seen microbial population?

Answer 47

fungal zoospores, protozoa, and bacteria

Question 48

stomach is what percent?

Answer 48

9%

Question 49

small intestine is what percent?

Answer 49

28%

Question 50

cecum is what percent?

Answer 50

17%

Question 51

large colon is what percent?

Answer 51

35%

Question 52

small colon is what percent?

Answer 52

11%