Intro to GI Tract Diseases

Question 1

Digestion

Answer 1

process of breaking down complex nutrients into simple molecules (so they can be absorbed)

Question 2

Absorption

Answer 2

process of transporting simple molecules across intestinal epithelium into bloodstream

Question 3

Where does digestion begin?

Answer 3

in the mouth

Question 4

Digestion in the mouth:

Answer 4

teeth grind food (chewing) and cover it in saliva

Question 5

Saliva

Answer 5

-lubricates food so it can pass through the esophagus
-buffers the stomach
-starts digesting starches (but not much)

Question 6

When do horses produce saliva?

Answer 6

only when chewing

Question 7

Choke

Answer 7

food is stuck (not chewed or lubricated enough) in the esophagus
-can lead to aspiration pneumonia
-EMERGENCY

Question 8

Esophagus

Answer 8

tube connecting the mouth to the stomach
-no secretion
-just peristalsis (pushing food forward)

Question 9

Stomach

Answer 9

-gastric juices
-stomach acid secreted all the time (unlike humans-only when we eat)

Question 10

What does the stomach digest?

Answer 10

protein

Question 11

What is the role of the cardiac valve?

Answer 11

closes off food from going from the stomach back to the esophagus (horses cannot vomit or eructate)

Question 12

What does the small intestine digest?

Answer 12

enzymatic digestion

Question 13

Bile

Answer 13

-produced by the liver
-digests fat in the SI

Question 14

Pancrease

Answer 14

helps in the digestion of protein, fat, and starch

Question 15

Where are the majority of sugars absorbed?

Answer 15

small intestine (leads to increase in blood glucose 30 min after a meal)

Question 16

What is absorbed in the small intestine?

Answer 16

-vitamins
-minerals
-sugars

Question 17

What is secreted into the small intestine?

Answer 17

bile and large volumes of water

Question 18

What are the three sections of the small intestine?

Answer 18

-duodenum
-jejunum
-ileum

Question 19

What raises risk of choke?

Answer 19

-bad teeth
-coarse hay
-dry hay

Question 20

What valve separates the small intestine from the large intestine?

Answer 20

ileocecal valve

Question 21

What are the sections of the large intestine?

Answer 21

-cecum
-large colon
-small colon

Question 22

What is absorbed in the large intestine?

Answer 22

water and water-soluble proteins

Question 23

Large intestine

Answer 23

microbial fermentation of material that was not digested in the small intestine (fiber)

Question 24

Water moves via…

Answer 24

osmosis

Question 25

Hypoosmotic

Answer 25

sends water to areas with less solutes

Question 26

Hyperosmotic

Answer 26

sends water to areas with more solutes

Question 27

Everything we eat is considered hyper or hypoosmotic?

Answer 27

hyperosmotic

Question 28

What causes gastric ulcers?

Answer 28

if horses do not have food in their stomachs, gastric juices can splash up

Question 29

How long does food stay in the stomach

Answer 29

not long (feed/concentrates stay longer)

Question 30

How long can it take for digestion to complete?

Answer 30

up to 2 days

Question 31

Pyloric sphiincter

Answer 31

the valve from the stomach to the small intestine

Question 32

Glandular region of the stomach

Answer 32

contains glands that secrete mucus, gastric juices, and digestive enzymes
-the mucus protects the stomach lining (prostaglandins)

Question 33

Aglandular region of the stomach

Answer 33

Rougher lining, no secretions, can be harmed by stomach acid

Question 34

What are the 3 types of plant carbohydrates?

Answer 34

-fiber
-sugars
-starches

Question 35

Fiber

Answer 35

structural part of plants and an important energy source for herbivores
-cannot be digested by mammalian enzymes (needs to be broken down by microbes through fermentation)

Question 36

When does grass have the most fiber/water?

Answer 36

when it is young

Question 37

What does eating young grass cause?

Answer 37

-cowpie/loose feces
-causes bloat
-usually in the spring

Question 38

What influences water movement?

Answer 38

water moves in whatever direction necessary to keep ingesta iso-osmotic
-entering the gut when ingesta is hyperosmotic
-leaving the gut when ingesta is hypo-osmotic

Question 39

What is water absorption dependent on?

Answer 39

nutrient absorption

Question 40

Diarrhea

Answer 40

-increase in frequency of defecation or fecal volume
-volume is an increase in water content
-mismatch between secretion and absorption

Question 41

What is water in the GI tract a sum of?

Answer 41

-ingested water
-water secreted in intestines

Question 42

Water absorbed is ____ than the _____ of water ingested and water secreted leaving water for the passage of feces

Answer 42

less; sum

Question 43

What can happen if ingesta is too dry?

Answer 43

it can cause impaction colic

Question 44

When does diarrhea occur?

Answer 44

when absorption is inadequate to recover secreted water
-generally because of loss of GI epithelium (bacterial, viral, or protozoal infection)

Question 45

How does infection lead to diarrhea?

Answer 45

it destroys villi, which impedes nutrient absorption, leading to impaired water absorption

Question 46

What sometimes happens to horses that have diarrhea at a young age?

Answer 46

they often don’t return to normal

Question 47

What happens to horses when they get diarrhea?

Answer 47

they get dehydrated quickly

Question 48

Where does the majority of gastric ulcers occur?

Answer 48

in the aglandular part of the stomach

Question 49

What type of horse is more prone to pyloric ulcers?

Answer 49

warmbloods

Question 50

Pyloric ulcer is ______ to treat

Answer 50

hard

Question 51

Concentrates increase or decrease the pH of the gut?

Answer 51

decrease

Question 52

What is needed to buffer the stomach?

Answer 52

calcium