“The Equine Digestive Tract” Quiz
October 2010 Issue of Forage for Thought
Answers and explanations are shown below
1. One of the ways a horse’s stomach is different than our own is:
a. A horse’s stomach produces acid continuously, even when it’s empty whereas our stomach only produces acid when we eat.
b. A horse’s stomach as four compartments, whereas our stomach only has one.
c. A horse’s stomach can digest fiber, whereas our stomach cannot.
2. Ulcers can easily form in the upper “squamous” area of the horse’s stomach because:
a. There is no protective mucous lining in this area, like there is in the lower, glandular portion of the stomach.
b. When a horse runs, the acid sloshes to this upper portion, where it is unprotected by the mucous that lines the lower portion.
c. Both a and b describe the situation.
d. Neither a, nor b, are correct. The horse’s stomach is protected throughout the entire lining by a mucous layer.
3. Concentrated meals should weigh no more than 4 lbs for the full-sized horse because:
a. The stomach is relatively small compared to the rest of the gastrointestinal tract – only holding between 2 and 4 gallons.
b. The small intestine cannot produce enough digestive enzymes for a large meal.
c. There will be too much manure formed, leading to constipation.
d. The meal will settle at the bottom of the cecum, leading to colic.
4. The entrance and exit to the cecum is the same opening, and it is at the top.
a. True
b. The entrance and exit are same opening but it is at the bottom.
c. The entrance is at the top and the exit is at the bottom.
5. Saliva:
a. Is produced when a horse chews
b. Is a natural antacid
c. Provides moisture to ease swallowing
d. a, b, and c are correct
e. None are correct – saliva is produced in the stomach.
6. The foregut consists of the:
a. Stomach and small intestine
b. Small intestine and cecum
c. Cecum and large colon
7. The hindgut consists of the:
a. Stomach and small intestine
b. Small intestine and cecum
c. Cecum and large colon
8. To prevent feedstuffs from sinking the bottom of the cecum (causing colic), it is important to:
a. Provide free access to water and encourage your horse drink
b. Provide a steady supply of forage so the cecal muscles can have something upon which to contract, thereby pushing digested forage toward the top
c. Allow as much turnout as possible to keep the horse moving; standing still interferes with the muscular motion of the gastrointestinal tract.
d. a, b, and c are all important
e. None of the answers is important in regard to the cecum since the cecum exits at the bottom and gravity does the work.
9. Fiber (mainly from forage) is digested:
a. In the stomach
b. By the digestive enzymes in the small intestine
c. By the microbes that produce digestive enzymes, residing in the hindgut
d. Fiber cannot be digested – that’s why the diet should consist mostly of digestible carbohydrates like sugar and starch.
10. Carbohydrates (sugars and starch), protein, and fat, are mainly digested:
a. In the stomach
b. By the digestive enzymes in the small intestine
c. By the microbes that produce digestive enzymes, residing in the hindgut
d. Carbohydrates, protein, and fat are not well digested anywhere.
11. If too much starch reaches the hindgut, it will be fermented by the microbial population, leading to lactic acid production. This destroys microbes, can cause colic, and even lead to laminitis (founder).
a. The whole statement is true.
b. The whole statement is false.
c. It is true except that excess starch cannot cause founder.
This material is discussed in detail in two chapters: Chapter 1 -- Ground Rules for Feeding A Horse and Chapter 14 -- Digestive Problems, in Feed Your Horse Like A Horse
Answers:
1. A
2. C
3. A
4. A
5. D
6. A
7. C
8. D
9. C
10. B
11. A
1. One of the ways a horse’s stomach is different than our own is:
a. A horse’s stomach produces acid continuously, even when it’s empty whereas our stomach only produces acid when we eat.
b. A horse’s stomach as four compartments, whereas our stomach only has one.
c. A horse’s stomach can digest fiber, whereas our stomach cannot.
2. Ulcers can easily form in the upper “squamous” area of the horse’s stomach because:
a. There is no protective mucous lining in this area, like there is in the lower, glandular portion of the stomach.
b. When a horse runs, the acid sloshes to this upper portion, where it is unprotected by the mucous that lines the lower portion.
c. Both a and b describe the situation.
d. Neither a, nor b, are correct. The horse’s stomach is protected throughout the entire lining by a mucous layer.
"C" is correct -- the upper portion is unprotected and most horses that do speed events, have ulcers.
3. Concentrated meals should weigh no more than 4 lbs for the full-sized horse because:
a. The stomach is relatively small compared to the rest of the gastrointestinal tract – only holding between 2 and 4 gallons.
b. The small intestine cannot produce enough digestive enzymes for a large meal.
c. There will be too much manure formed, leading to constipation.
d. The meal will settle at the bottom of the cecum, leading to colic.
"A" is correct -- the stomach is the first organ of the digestive tract and can rupture if the meal size is too large.
4. The entrance and exit to the cecum is the same opening, and it is at the top.
a. True
b. The entrance and exit are same opening but it is at the bottom.
c. The entrance is at the top and the exit is at the bottom.
"A" is the answer -- because this is true, there must always be forage in the cecum, as well as water, to allow for muscle contraction and the ability to push the digested feed up through the top.
5. Saliva:
a. Is produced when a horse chews
b. Is a natural antacid
c. Provides moisture to ease swallowing
d. a, b, and c are correct
e. None are correct – saliva is produced in the stomach.
"D" is correct -- all three describe saliva.
6. The foregut consists of the:
a. Stomach and small intestine
b. Small intestine and cecum
c. Cecum and large colon
"A" is correct -- the cecum and large colon are considered the hindgut.
7. The hindgut consists of the:
a. Stomach and small intestine
b. Small intestine and cecum
c. Cecum and large colon
"C" is correct. The stomach and small intestine are considered the foregut.
8. To prevent feedstuffs from sinking the bottom of the cecum (causing colic), it is important to:
a. Provide free access to water and encourage your horse drink
b. Provide a steady supply of forage so the cecal muscles can have something upon which to contract, thereby pushing digested forage toward the top
c. Allow as much turnout as possible to keep the horse moving; standing still interferes with the muscular motion of the gastrointestinal tract.
d. a, b, and c are all important
e. None of the answers is important in regard to the cecum since the cecum exits at the bottom and gravity does the work.
"D" is correct -- since the exit is at the top, all of the answers are necessary to prevent colic.
9. Fiber (mainly from forage) is digested:
a. In the stomach
b. By the digestive enzymes in the small intestine
c. By the microbes that produce digestive enzymes, residing in the hindgut
d. Fiber cannot be digested – that’s why the diet should consist mostly of digestible carbohydrates like sugar and starch.
"C" is correct -- the horse itself cannot digest fiber -- only the bacteria, which produce digestive enzymes. That's why those hindgut microbes are so important!
10. Carbohydrates (sugars and starch), protein, and fat, are mainly digested:
a. In the stomach
b. By the digestive enzymes in the small intestine
c. By the microbes that produce digestive enzymes, residing in the hindgut
d. Carbohydrates, protein, and fat are not well digested anywhere.
"B" is correct -- the horse can digest carbohydrates, as well as protein and fat and it's done in the foregut.
11. If too much starch reaches the hindgut, it will be fermented by the microbial population, leading to lactic acid production. This destroys microbes, can cause colic, and even lead to laminitis (founder).
a. The whole statement is true.
b. The whole statement is false.
c. It is true except that excess starch cannot cause founder.
"A" is correct -- excess starch is one of the main causes of laminitis (founder) when starchy meals are fed at too high levels (or if the horse gets into the grain bin).