digestion Flashcards
what are the three main factors that losses are associated with
digestion
absorption
metabolism
digestibility definition
proportion of feed that is not excreted
4 losses of feed energy
feces
urine
methane
heat increment
what is the most important factor affecting digestibility
fiber
factors affecting digestibility
nutrient composition
plant species
within species differences
forage maturity
level of intake
associative effects
processing roughages
temperature
are annual or perennial grasses generally more digestible
annual
T/F Legumes are generally more digestible than grasses
TRUE
grass digestibility ranking
legumes > cool season > warm season
within species differences affecting digestion
-leaf:stem ratios
-amount of lignin(GMO v non GMO)
how does plant maturity effect digestibility and quantity
as plant maturity increases so does quantity, but digestibility decreases
why does digestibility decrease as the plant ages
the cell wall becomes thicker
what effect does plant maturity have on feed intake
as plant maturity increases
feed intake decreases
how much is digestibility decreased per each multiple increase in feed intake
4%
EX 12 lb : 70% digestible
24 lb : 66% digestible
T/F decrease in digestibility due to feed intake occurs in all species
FALSE. happens most severely in ruminants
T/F associative effects only impact reminants
TRUE
what is an example of a positive associative effect
low-quality forage fed with cottonseed meal.
CSM gives microbes energy to better digest forage
what happens to digestibility when you process roughage? why? what happens to feed intake?
digestibility decreases.
feed spends less time in the GI tract
feed intake increases
what happens to digestibility and feed intake when you process grains
digestibility increases
feed intake decreases
T/F both heat and cold stress have an impact on digestibility
FALSE. heat stress seems to have no impact on digestibility
what is the change in digestibility as temperatures decrease
digestibility decreases
what forms of energy loss does TDN not account for
urine
methane
heat increment
