CHO: Ruminant Digestion And Absorption Flashcards
Where does digestion of fiber occur in ruminants?
In the large intestine
Sugars produced by fiber digestion are fermented by what?
Microbes
In the rumen, carbohydrates are fermented into VFAs. They are then absorbed by?
Rumen wall
What are the 4 contents of the rumen?
Feed, saliva, microbes, microbe waste products
Specialized bacteria live in the rumen in what 4 ways?
In the liquid phase, loosely and firmly adhered to feed particles, and attached to Protozoa surface
In rumen metabolism, carbohydrate molecules are converted into what through oxidation glycolysis?
Pyruvate
What does pyruvate get converted into?
VFAs, CO2, CH4
What is a disadvantage of rumen metabolism?
Lose energy and glucose
What does the rumen absorb?
VFA and microbial protein
What does the hind gut absorb?
Only VFAs
Where do ruminants get the majority of their energy?
Volatile fatty acids and feed
What are the 3 volatile fatty acids used ruminants?
Acetate, propionate, and butyrate
What is the primary role of acetate and butyrate?
Energy
What’s the primary role of propionate?
Glucose precursor
Why is there less energy in forages?
Because forages are less digested, and actually take more energy to digest and they’re bulkier in the dig tract
Where does beta- hydroxybutyric acid come from?
Butyrate
Rumen acidosis means that?
Lactic acid production exceeds absorption
What are some causes of acidosis?
Animals gorge on feed, high concentrate diet, heat stress, infrequent feeding
What is the primary milk yield determinant?
Lactose synthesis
Forage is a source of what VFA?
Acetate
Propionate comes from what feedstuff?
Concentrates
What do concentrates do to rumen pH?
Decrease it because there is less buffer production and faster rates of acid production
Starch degradation varies with what?
Fermentation or digestion
What are some things that affect fermentation rates?
Grain type, harvest /storage method, processing
