Final Flashcards
(26 cards)
2 advantages that the ruminant GIT provides (vs NR)
1) More efficient herbivores, can digest incalcitrant feeds before SI absorption
2) Avoid predators w crepuscular behavior
4 defining characteristics of a ruminant
1) ungulates (2 toes)
2) multiple chambered stomach/ have rumen and ruminate (pregastric ferm)
3) pecorans (used to have headgear)
4) Mammals
5) No upper incisors
6) Obligate herbivores
5 sacs of the rumen + bio advantage vs 1 compartment
1) cranial/cardi
2) ventral
3) ventral blind/caudal
4) dorsal blind/caudal
5) dorsal
contract @ different times (peristaltic and antiperistaltic) to churn feed for digestion/ferm
2 factors that influence digestion of feed
1) chemical/physical properties of feed
2) residence/retention time and rate of passage
3) rate of ferm
2 examples of ferm end products not useful to ruminant
1) CH4
2) CO2
Why do rum species have different grazing strategies related to body size
Different grazing bhvrs allow animals w smaller rumens (browsers) to eat easier to digest feeds because they can’t keep feed in their rumen to ferm for as long. Large ruminants (grazers) can eat low qual feed because they have more ferm.
3 different grazing strategies and differences
1) Browsers (goats) : small, eat fruits/leaves/nuts/easier to ferm feeds
2) Grazers (cattle) : large, eat stems/stalks/leaves, more ferm
3) Intermediate Feeders (sheep): midsize, eat browse + stems/stalks
3 short chain VFAs
1) Acetate
2) Propionate
3) Butyrate
What fiber component reflects all of the fiber found in plants
NDF (neutral detergent fiber)
What is the difference between material insoluble in acidic and neutral detergent?
Hemicellulose
Why do we feed carbs to ruminants?
To supply energy
-cheap
-easy
-high availability
4 examples of ways that VFA prod can be manipulated
1) incr grain/starch content (decr fiber)
2) add ionophores or buffer
3) feed multiple small meals
4) increase fiber (decr grain/starch)
5) process feed
Primary difference btwn starch and cellulose
starch has alpha glycosidic bonds, cellulose has beta (indigestible)
Which VFA accounts for at least 50% of ruminal short chain FAs
acetate
why is incr lactic acid prod in the rumen a concern
lactic acidosis
why is incr propionate associated w improvements in feed efficiency in rum
can be converted to glucose to incr blood glucose, uses up H+ so less energy waste through CH4
primary structural hereropolysaccharide that closely associates with lignin
hemicellulose
Which type of starch is less soluble and why
amylose- it is linear (less pts to remove glucose)
what is physically effective NDF
scratch factor, all NDF over 1.2 mm in length, req incr rumination (incr saliva buffers rumen pH)
Why is peNDF related to ruminal pH
needs more rumination so animal makes more saliva (swallowed to buffer rumen)
ex of negative associative effect? why would it occur?
feed too much fat so digestion decreases- microbes in rumen don’t fn well with high fat, so the animal gets less E even though you feed more
what happens to AAs provided in excess
deaminated: split into NH3 (-urea-urine) and C skeleton (-E pathways-ATP or Glucose)
CP in diets consists of TP and NPN. Which N source in DP can contribute to RDP and RUP?
True Protein
(CP--- NPN–RDP—MCP–\
–TP—-/—RUP———-MP)
Primary goal of providing RDP to rum
Feed microbes (MCP/microbial growth)
