ruminant forestomach

Question 1

what are three unique things about ruminants

Answer 1

• cloven footed
• chews cud
• digest plant cellulosic material

Question 2

what are pesudoruminants

Answer 2

• 3 chambered stomach
• camels and hippos

Question 3

what stomachs do marsupials have

Answer 3

• anterior sacciform and posterior tubiform stomach
• don’t produce methane

Question 4

what is the rumen linked to

Answer 4

• improved feed efficiency
• multidrug resistance
• cellulosic ethanol
• greenhouse gases
• improved forage varieties

Question 5

is the rumen functional at birth

Answer 5

no - neonates are like monogastrics
up until 3 mo. of age

Question 5

how much does the reticulorumen occupy of mature volume

Answer 5

80%

Question 6

folds

Answer 6

areas of tissues dividing the reticulorumen into different compartments

Question 7

pillars

Answer 7

muscular areas that forms grooves on the outside of the rumen

Question 8

how many chambers is the rumen divided into and what are they

Answer 8

5
* crainal chamber
* dorsal chamber
* ventral chamber
* dorsal blind sac
* ventral blind sac

Question 9

reticulum

Answer 9

• honey comb appearance
• feed forms a bolus
• regurgitation initiated
• collects hardware

Question 10

rumen

Answer 10

• papillary lining
• harbors microbes
• absorption of VFA
• primary digestion

Question 11

omasum

Answer 11

• muscular folds/laminae
• particle size reduction
• more absorption
• connects to abomasum

Question 12

what is the capacity of the reticulo-rumen in cattle

Answer 12

125L

Question 13

what is the capacity of the reticulo-rumen in sheep

Answer 13

17L

Question 14

why is the capacity of the reticulo-rumen so large

Answer 14

large capacity needed for feed to be fermented

Question 15

what are the factors that govern the process within the rumen

Answer 15

physical, chemical and microbial

Question 16

what are the driving forces of the rumen

Answer 16

dietary, host, environmental, and health factors

Question 17

pH of rumen

Answer 17

6-7

Question 18

rumen contractions help with

Answer 18

• digesting feed material
• allows for determining how much time the feed spends in the rumen

Question 19

layers of rumen (stratified)

Answer 19

• gas
• course hay (rumen mat)
• liquid in center
• fine particles in ventral sac of rumen

Question 20

why is the rumen mat important

Answer 20

microbial colonization and feed fermentation

Question 21

what are the 4 Rs in rumination

Answer 21

• regurgiation
• remastication
• reinsalivation
• redeglutition

Question 22

regugitation

Answer 22

reverse peristalsis carries food to mouth

Question 23

remastication

Answer 23

• liquid squeezed from bolus and swallowed
• bolus chewed

Question 24

reinsalivation

Answer 24

adding more saliva

Question 25

redeglutition

Answer 25

swallowing bolus and liquids

Question 26

what are the two types of contractions

Answer 26

1. primary 2. secondary

Question 27

what is primary contraction

Answer 27

initiated in the reticulum * helps movement of digesta and facilitates rumination * mixing contraction * evacuation contraction

Question 28

what is secondary contraction

Answer 28

starts in rumen and helps with erucation

Question 29

where do heavier particles (digested particles go)

Answer 29

pushes to cranial sac-reticulum-RO orifice

Question 30

where do lighter particles (undigested) go

Answer 30

join the mat in the dorsal sac-ventral sac pushed to cranial sac to esophagus through cardia

Question 31

where do high densisty foreign bodies go

Answer 31

pushed towards both RO orifice and cardia and settle in the floor of the reticulum

Question 32

what are the 4 functions of contractions

Answer 32

* mixing incoming feed with existing to avoid stratification * fermentation productions towards wall for absorption * sort particles for rumination or passage through omasum * facilitate rumination and eructation

Question 33

primary and secondary contractions are under control of which nerve

Answer 33

vagus nerve

Question 34

eructation

Answer 34

expulsion of gases through mouth

Question 35

microbial fermentation of feeds produce large quantities of gases which accumulate where | CO2, CH4, H2

Answer 35

in the rumen

Question 36

how many liters of gas per cow per day is produced

Answer 36

650L (methane)

Question 37

what nerve controls eructation

Answer 37

vagus nerve

Question 38

what is the normal pH for the rumen

Answer 38

* 6.2 to neutral (or 5.5-7) * fibrous diet > 6; concentrate rich diet 5-6 * intra-day changes (5.5-7)

Question 39

how does diet control pH

Answer 39

saliva production

Question 40

long forage particles produce more

Answer 40

saliva - desirable

Question 41

what is the normal ruminal pressure

Answer 41

980 to 1020 mbar

Question 42

what is the normal ruminal temperature

Answer 42

38.5 - 39.5 degrees C

Question 43

the rumen is a capacious anerobic fermentation chamber that is colonized by

Answer 43

complex microbial ecosystem

Question 44

what kind of association exists between host and rumen microbes

Answer 44

symbiotic

Question 45

how much energy does microbial fermentation provide and how much protein needs of the host

Answer 45

>70%; 50%

Question 46

what are the benefits to the microbes

Answer 46

* anerobic conditions and moisture * energy: ATP released during fermentation * nitrogen from ammonia and peptides for growth * minerals and vitamins

Question 47

what are the benefits to the ruminants

Answer 47

* energy in the form of VFA * amino acids in the form of microbial protein * detoxification of antinutritional factors

Question 48

what are the side effects of symbiosis

Answer 48

* methane * biohydrogenation

Question 49

where are ruminal microbes found

Answer 49

* free in the liquid phase * attached to feed particles * attached to epithelial lining of rumen * attached to protozoa * methanogens

Question 50

pH > 6 | microbes

Answer 50

fiber digesters

Question 51

pH < 6 | microbes

Answer 51

amylolytic digesters

Question 52

pH - 5.5

Answer 52

lactic acid producers - dysbiosis in the rumen microbiota

Question 53

frothy rumen contents is due to what

Answer 53

accumulation of polysaccharide slime that traps gas and inhibits erucation mechanism

Question 54

what type of feed predisposes ruminants to frothy bloat

Answer 54

forages (alfalfa, winter wheat) high in soluble sugars and proteins