Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physiology > Ruminant Physiology > Flashcards

Ruminant Physiology Flashcards

1
Q

Special features of ruminants

A
  • able to utilize forages other mammals cannot digest
  • forestomachs
  • esophageal and reticulo-omasal groove to bypass rumen
  • no upper incisors or canine teeth (dental pad)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Members of ruminant class

A
  • cattle
  • sheep
  • goats: low fiber, discriminant/browser
  • camelids (pseudoruminant)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Location of forestomach

A
  • rumen/reticulum is on the left side
  • omasum is in the middle
  • abomasum is on the right side
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Advantages

A
  • break down cellulose to usable nutrients
  • allows synthesis of high biological value protein: low biological plant protein, non-protein nitrogen, nitrogenous end product (urea)
  • production of all B vitamins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Disadvantages

A
  • regular food intake at regular intervals
  • long hours chewing: food ingestion (4-7 hrs/day), chewing cud (8 hrs/day)
  • keep rumen fermentation vat balanced: large quantities of alkaline saliva, constant mixing, release of gas products
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Rumen layers

A
  • gas
  • fiber mat/raft
  • fluid slurry (small particles)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Roughages

A

Cellulolytic

  • cellulose: glucose
  • hemicellulose: xylose
  • pectin: galactose
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Legumes

A

Cellulolytic

- able to fix nitrogen (high protein)

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

Grains

A

Amylolytic

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

Requirements for fermentation

A
  • regular addition of fresh food
  • presence of suitable microbes
  • steady removal of end products: gas, VFA, simple compounds, undigestible material
  • continuous mixing
  • propulsion of fine particles and fluid
  • anaerobic
  • stability: temperature, osmotic pressure, redox and pH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Protozoa

A
  • live in fiber mat
  • very sensitive to change
  • feed on bacteria, plant starch and PUFAs
  • provide high biological value protein
  • prefer pH of 6.2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

10^10 bacteria/gram rumen content

A 
Cellulolytic bacteria
- pH of 6.2
Amylolytic bacteria
- pH of 5.8
Lactobacillus spp.
- takes over at pH <5.8
- lactic acid producing (creates rumen acidosis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Rumen dysfunction

A
  • normal rumen pH 5.5-7.0
  • rapid feed changes
  • oral antibiotics
  • die off of normal rumen fauna
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Rapid feed changes cause

A
  • acute acidosis/grain overload: pH < 5.0
  • subactue acidosis/SARA: pH < 5.5
  • takes 2 weeks for rumen fauna to adjust
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Products of fermentation

A
  • gases: methane (CH4 and CO2) is eructated
  • volatile fatty acids: absorbed across rumen wall
  • microbial and protozoal protein and lipids: passed thru to abomasum
  • ammonia: absorbed across rumen wall
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Volatile fatty acids

A
  • acetate: ketogenic
  • butyrate: ketogenic
  • propionate: glucogenic
  • ketone bodies: acetone, acetoacetate, betahydroxybutyrate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Is glucose available for absorption?

A

NO

  • blood glucose levels in ruminants is lower
  • insulin is lower
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Acetic acid

A
  • minimal liver use
  • oxidized throughout most of the body to generate ATO
  • major source of acetyl CoA for synthesis of lipids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Proprionic acid

A
  • major liver use: removed from portal blood by liver
  • serves as a major substrate for gluconeogenesis
  • critical to the ruminant because almost no glucose reaches the small intestine for absorption
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Butyric acid

A
  • comes out of the rumen as the ketone beta-hydroxybutyric acid
  • oxidized in many tissues for energy production
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How long does it take to fast a ruminant

A

24-48 hrs of no food, 12 hrs no water

22
Q

High fiber diets produce more _____

A

Acetate and butyrate

- higher butterfat in milk

23
Q

High grain diets produce more ______

A

Proprionate

- higher milk volume but lower butterfat

24
Q

Protein metabolism

A

Broken down to simplest form (ammonia)

  • deamination of plant proteins
  • urea from diet and saliva
  • may feed up to 30% urea in diet (NPN)
  • utilization of urea requires adequate energy in form of VFA or starch
25
Q

Gas production

A

Up to 40 L/hour 204 hours after a meal

26
Q

Green house gases

A
  • water vapor, carbon dioxide, methane, nitrous oxide, and ozone
  • carbon dioxide, CH4, and N2O
  • fossil fuel combustion, iron and steel prodution, cement manufacturing and municipal solid waste combustion
27
Q

Methane makes up _____ of green house gases

A

7.9%

28
Q

_______ has decreased, but milk production has increased 4 x per cow

A

Number of dairy cows

- working on feed additive to decrease methane

29
Q

Rumen motility/rumination

A
  • mixes rumen fermentation vat continuously
  • allows for regular release of gas (eructation)
  • allows for cud chewing: reduces particle size and increases saliva flow
  • filters fluid and particulate matter thru to omasum and abomasum
30
Q

Innervation of forestomachs

A 
Parasympathetic
- vagus, CN 10
- promotes rumination, cud chewing
Sympathetic
- thoracic ganglia to celiac
- decreases motility
Nervous cows
- drip/drool saliva
- decrease (increase/hypermotile) rumen contractions
31
Q

Types of rumen contractions

A
  • primary: mixing and cud chewing
  • secondary: eructation
  • primary and secondary: cud chewing with eructation
32
Q

Reticulum

A
  • catches solid material
  • source of Hardware disease
  • prevention via magnet
  • other dietary indiscretions include: plastic bags, placenta, other
33
Q

Omasum

A
  • very fine particles
  • large surface area
  • absorption of VFAs, electrolytes and water
  • minor fermentation
  • regulates propulsion into abomasum
  • episodic slow contractions independent of reticular contractions
34
Q

Abomasum

A
  • true glandular stomach
  • pepsinogen and HCl secretion
  • average pH 3
  • motility present but not well defined in fundic area
  • peristalsis of pyloric area at 6/minute
35
Q

Differences in ruminants

A
  • fasting for surgery

- blood glucose not as high (45-75 mg/dl)

36
Q

Special features of calves

A
  • are nonruminants at birth
  • reticulorumen is undeveloped
  • lack sucrase and secrete limited amylase
  • cannot digest plant proteins, unsaturated fats
  • dependent on milk sugars, glucose, milk protein and fat
  • liquid diets composed of milk, milk replacers, fermented colostrum
  • esophageal groove
37
Q

Requirements for ruminal development

A
  • establishment of bacteria in the rumen
  • liquid in the rumen (water)
  • outflow of material from the rumen (muscular action)
  • absorptive ability of the tissue
  • substrate
38
Q

Development of rumination

A
  • cud chewing has been observed at 7 days
  • by 2 months the calf can be weaned
  • by 4 to 6 months the rumen is fully functional
  • by 9 months the rumen is the same proportion of body weight as adult
39
Q

Esophageal groove closure

A

Milk bypasses rumen - goes to abomasum

  • muscular groove seals rumen opening
  • stimulated by suckling
  • chemcially closed by sodium chloride solution, sugar solution, sodium bicarb
40
Q

Ruminal drinkers

A
  • failure of esophageal groove to close
  • over feeding
  • mismothering/starvation
  • putrefaction of rumen contents
  • treatment: modified feeding schedule, small amounts often, probiotics
41
Q

Beginning rumination

A
  • need fresh water to provide ample liquid for the rumen
  • bacteria needed to produce VFA (early bacteria are aerobic, similar to adults by 2 weeks)
  • substrate - volatile fatty acids (coarse material or high fiber placed in rumen have no effect on development) –> dilute solutions of VFA placed in rumen stimulate development
  • development of the rumen wall and papillae depend on grain intake
42
Q

Important points

A
  • calves need access to drinking water

- offer small amounts high quality calf starter daily (1 cup replaced daily if not eaten)

43
Q

Salivary glands

A 
Major
- parotid (3rd cheek tooth): serous
- mandibular: mixed
- sublingual: mixed
Minor
- buccal, lingual, palatine: mucous
Production: lysozyme, no amylase
Volume: up to 200 L/day (100-150)
44
Q

Composition of saliva

A

Isotonic to plasma

  • alkaline pH 8.1
  • Na: 170 mEq/L
  • K: 13 mEq/L
  • HCO3: 48 mEq/L
  • Cl: 11 mEq/L
  • PO4
  • nitrogen (77% as urea)
45
Q

Functions of saliva

A
  • moistens food/aids in deglutition
  • buffers acid production in rumen
  • provides nitrogen for microbial production of amino acids
  • protects against protein deficiency
46
Q

Do ruminants produce saliva with atropine?

A

Yes, continuously

47
Q

Clinical issues

A
  • high grain diets decrease cud chewing and salivation (decreases buffering)
  • salivation issue with general anaesthesia
  • nervous animals: excessive drooling
48
Q

Problems with swallowing

A
  • choke
  • listeria: interferes with hypoglossal nerve
  • trauma/fractures of jaw
  • serious ECF, electrolyte and bicarb loss
49
Q

Rumen

A
  • fermentation

- absorption of VFAs, ammonia

50
Q

Reticulum

A
  • keeps large particles from entering omasum

- eructation and cud chewing

51
Q

Omasum

A
  • continues fermentation

- absorbs VFAs

52
Q

Abomasum

A
  • acid secreting for digestion

- true stomach

Physiology (33 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions