Acidosis

Question 1

rumen temp

Answer 1

38-41 with decrease between meals

Question 2

normal rumen pH range

Answer 2

5.5-6.9

Question 3

rumen microbiota relative populations

Answer 3

most bacteria, then bacteriophages, then protozoa, then methanogens, then fungi,

Question 4

3 types of microbe communities

Answer 4

particle associated: up to 75% high enzymatic activity
liquid associated: up to 50%, utilize soluble nutrients
epimural associated: more stable, urease activity

Question 5

SCFA

Answer 5

major energy supply
production released ATP for microbial growth
difficult to measure production

Question 6

major VFA, what changes between forage and concentrate diets

Answer 6

always mostly acetate
when on concentrate propionate increases

Question 7

SCFA and lactic acid pKA
what does this mean

Answer 7

SCFA = 4.9
lactic acid = 3.9
at lower pH SCFA doesn’t grow as well and lactic grows better

Question 8

predominant lactate isomer in the rumen

Answer 8

L lactate

Question 9

absorption difference between L and D lactate

Answer 9

L lactate absorbs better. D is more predominant at lower pH and sticks around longer snowballing acidity

Question 10

SARA pH

Answer 10

5.2-5.6 for atleast 3h in a day

Question 11

acute acidosis pH

Answer 11

below 5.0 (5.2)

Question 12

bacteria linked to liver abscess increase when pH

Answer 12

decrease

Question 13

lactic acid utilizers trend for SARA and acute

Answer 13

lactic acid utilizers are increased in SARA and decreased in acute
cant deal with acute issues

Question 14

main and other acid removal methods from rumen

Answer 14

main is absorption
others are bicarb and passage

Question 15

relation between salvia and acidosis

Answer 15

more saliva does not prevent acidosis as more saliva comes from more intake which means more ferm to deal with

Question 16

how does HCO3- get into rumen

Answer 16

antiport with VFA between rumen and blood stream

Question 17

is bicarb higher in roughage or concentrate diets for salivary bicarb and rumen bicarb

Answer 17

salivary bicarb is higher in roughage
rumen bicarb is higher when on concentrate

Question 18

main mechanisms for the removal of acid from ruminal contents (5)

Answer 18

saliva
passive diffusion of SCFA across rumen wall
SCFA absorption antiport with bicarb
carbonic anhydrase
passage of acid out of rumen

Question 19

why consider ruminal acidosis

Answer 19

animal welfare
decreased performance
associated disorders
mortality

Question 20

causes of acidosis

Answer 20

incr VFA production
excess grain
increase in dietary carb
insufficient fiber
insufficient buffering
sorting feed

Question 21

SARA consequences

Answer 21

metabolic acidosis
death
poor performance

Question 22

chronic SARA acidosis consequences

Answer 22

poor bunk management
cyclic intake pattern
reduced performance

Question 23

types of bloat

Answer 23

free grass
frothy (can be feedlot due to microbial factors or pasture due to plant components)

Question 24

consequences of acidosis

Answer 24

decr feed intake
decr absorptive capacity
incr liver abscesses

Question 25

how do liver abscesses happen

Answer 25

low pH deteriorates rumen wall, bacteria invade systemic circulation, hepatic blood stream takes to liver where it becomes encapsulated 1-2 small abscesses is severe

Question 26

laminitis

Answer 26

low pH degrades rumen wall allowing bacteria to enter systemic circulation and translocate causing infection vascular seepage causes edema, hypoxia, degradation of corium and irreversible damage

Question 27

cost to inflammation

Answer 27

induces glucose utilization that should be used for growth instead increases liver amino acid uptake decreased growth and feed efficiency

Question 28

where does acidosis have a significantly different pH than normal

Answer 28

Rumen Cecum Proximal colon distal colon

Question 29

mucin cast

Answer 29

bandaid on LI to try and recover from pH damage comes out in feces

Question 30

what areas should you target when trying to mitigate ruminal acidosis

Answer 30

reduce fermentability feeding management

Question 31

how to reduce fermentability

Answer 31

increase fiber, byproducts, and fat

Question 32

what to change in feeding management to reduce acidosis

Answer 32

frequency bunk management avoiding restriction improve dietary adaptation

Question 33

cascade of grain processing speed

Answer 33

wheat barley corn sorghum

Question 34

factors for variation in daily feed intake

Answer 34

weather missed feedings poor processing stale feed increasing too quickly

Question 35

when would you feed the higher grain diet if you are having acidosis issues

Answer 35

in the afternoon feeding