Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Physiology Exam 3 > Lecture 54- Ruminant Digestive Physiology I > Flashcards

Lecture 54- Ruminant Digestive Physiology I Flashcards

1
Q

What is the gastric stomach?

A

Abomasum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What makes up the ruminant forestomachs? What type of cells?

A

Rumen, reticulum, omasum

Stratified squamous epithelium
No glands
Pillars and papillae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe the evolution of ruminants. What is the digestive strategy?

A

Ingest enormous quantities of forage in short time minimizing exposure in the open

Spend maximal time ruminating in the protection of trees and rocks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the ruminant GIT compartmentalized in:

A

Rumen, reticulum, omasum, abomasum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How is pre-gastric fermentation accomplished?

A

By microbes

Allows animals to more completely utilize products of fermentation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Pseudoruminats have no ______

A

Omasum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where is the site of fermentation for ruminants?

A

Rumen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Where is the site of fermentation for non ruminants?

A

Cecum and large intestine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are examples of ruminant species?

A

Cattle
Bison
Sheep
Antelope
Goats
Deer
Elk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How is food physically broken down?

A

*prehension-lips, tongues
*mastication during eating + rumination.
Rumination = regurgitation + remastication
*microbial fermentation (accomplished by bacteria, fungi, yeast, Protozoa)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the three major salivary glands?

A

Parotoid
Sublingual
Mandibular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the composition and function of saliva?

A

Composition: bicarbonate, urea, K, inorganic phosphate, Cl

**Buffering is the number 1 function, adding moisture and lipase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which environmental conditions are needed to support fermentation?

A

Appropriate substrate
Temperature around 37
Osmolarity near 300 mOsm
Anaerobic conditions
Frequent mixing of ingesta
Particle size reduction
Indigestible material removal
Synchronized movement of fermented content to intestine
VFA must be buffered to maintain neutral pH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where does 60-75% of digestion occur? Also the primary site of fermentation?

A

Rumen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What do amylolytic bacterial species consist of?

A

Starch and sugars

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What do cellulolytic bacterial species consist of?

A

Cellulose, hemicellulose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the end products of fermentation?

A

Acetate, propionate, butyrate

*very important to remember: more acetate in high fiber and more propionate on high-grain**

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What do papillae and extensive capillaries do in the rumen?

A

Increase surface area, absorb

*larger on high grain diets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the function of the reticulum?

A

Form bolus for regurgitation
Move particles to omasum
Move particles to rumen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How do materials from rumen pass into omasum?

A

Via the reticulo-omasum orfice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does the omasum regulate?

A

Passage of digesta into lower tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is absorbed in the omasum?

A

Water and VFA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What do the gastric glands in the abomasum secrete?

A

HCl

Acidity kills microbes washing in from rumen—starts digestion
Major source of protein for animal essential AA -> digested and absorbed in SI

24
Q

What does the abomasum secrete? And why?

A

Pepsinogen

Hydrolysis microbial and dietary protein

25
How many times do abomasal contractions occur?
2-3 per minute Mixing, material exits to SI, and drive gas back into the rumen
26
What do forages contain?
Cellulose, hemicellulose, sugars, starch, protein, lignin
27
What do concentrates (grain) contain?
Starch, protein, sugar
28
What are the layers of the rumen?
-small high density on bottom -liquid -fibermat (larger, low density) -> scratch fiber -then gas layer
29
What are examples of micro flora?
Bacteria, Protozoa, fungi
30
Primarily feeding the ______—then the cow.
Flora
31
What is the definition of fermentation?
Microorganism-mediated transformation from one nutrient compound to another
32
Which products undergo fermentation in the rumen?
Monosaccharide Disaccharide Starch Cellulose Other Sugars
33
Which carbohydrates are fermented in the rumen to VFA? and at what percent?
Acetate (60%) Propionate (30%) Butyrate (10%) *acetate is higher with forage diets *butyrate is higher with grain diets
34
What does gluconeogenesis use to make glucose?
Propionate
35
What does fat synthesis utilize?
Acetate
36
What do ruminants use for energy?
VFA
37
What is the blood glucose in most non-ruminants? Is this lower or higher than normal?
60 mg/dl
38
What is the pathway for sugars, starch, cellulose, and lignin to turn into VFA?
Sugar -> VFA Starch -> Glucose -> VFA Cellulose -> Glucose -> VFA Lignin -> Undigested
39
What proteins fermented to?
Peptides Amino acids Ammonia Branched-chain VFA
40
What do microbes use in synthesizing cell walls and the cytoplasmic reticulum?
Protein components and metabolites
41
Where are dead microflora digested?
Small intestine
42
What provides the highest quality protein possible?
Microbes
43
(TRUE/FALSE) If you feed low quality proteins or metabolites (urea) the cow absorbs lowest quality amino acids from small intestine.
FALSE The cow absorbs the HIGHEST quality amino acids
44
What is ammonia produced in rumen from?
Protein fermation
45
What happens to the ammonia produced in the rumen?
Immediately utilized by microbes Absorbed and converted to urea by the liver
46
What are the three fates of urea?
1. Excreted by kidney 2. Recycled to saliva 3. Recycled to rumen
47
How do rumen primary contractions move?
Cranial to caudal
48
How do rumen secondary contractions move?
Caudal to cranial primarily to erucatate gas
49
What are reticular contractions associated with ?
Cud chewing
50
What are the four steps of rumination?
Regurgitation, reinsalviation, remastication, reswallowing
51
What is regurgitation initiated by?
Initiated by a reticular contraction AND relaxation of distal esophageal sphincter
52
When does rumination occur?
30-90 minutes after eating Occurs when animal is resting Ruminate up to 10 hours a day
53
What is the importance of rumination?
Rumination keeps food intake constant Removes air and gas pockets from forage -> allows particles to sink
54
What is rumination is initiated by?
“Extra” contraction of reticulum that pushes ingesta into area of cardia
55
Which esophageal sphincter opens during rumination?
Distal esophageal sphincter
56
What is the process of rumination?
1. Initiated by extra contraction of reticulum that pushes ingesta into area of cardia 2. Distal esophageal sphincter open 3. Inspirator excursion with glottis closed causing negative pressure in in trat Horacio esophagus 4. Bolus of ingesta moves into esophagus

Physiology Exam 3 (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions