Exam 2 Flashcards
What do high starch diets cause in ruminants
-Rapid fermentation
-SCFA and lactic acid production
-Decrease in rumen pH
-rumen acidosis
-disruption in ruminal function
When is rumen acidosis subclinical
pH is approximately 5.5
What are subclinical signs that the ruminant is undergoing rumen acidosis
-Decreased Intake
Gain
When is rumen acidosis clinical
when the pH is less than five
Clinical Signs of rumen acidosis
increase lactic acid
metabolic acidosis
damage to papillae
microbial death and release of endotoxins
Is subclinical or clinical rumen acidosis more dangerous
subclinical because you can’t usually see the signs so then you can’t treat it or manage it
Associated problems with rumen acidosis
parakeratosis (hardening of the papillae tissue)
liver abscesses
laminitis
Rumen Acidosis prevention
-reduce grain
-feed additives (buffers, ionopheres)
-the chewing of cud also helps because it produces saliva and helps buffer the pH
Glucose homeostasis in ruminants
50-80mg/dl
Glucose homeostasis in simple stomachs
80-120mg/dl
Why is there reduced glucose fluctuations in ruminants
-more time spent eating and ruminating
-prolonged digesta flow
-steady VFA production
-continuous glucogenesis
Glucose requirements in ruminants
don’t typically feed glucose to meet energy requirements since it rapidly ferments and drops pH
Source of glucose precursors in ruminants
1.) propionate
2.) amino acids
3.) lactic acid
4.) glycerol
Source of gllucose for ruminats
25% comes from diet and 75% comes from gluconeogenesis from propionate
Lipids
-“Lipos’ meaning fat
-insoluble in H20
-Hydrocarbons-CH2-CH2-CH2
-Not a polymer
Lipids energy compared to glycogen
6x equivelant mass of glycogen
Short Chain Fatty Acids
2-5 carbons
soluble in water
Fatty Acids
Hydrocarbon chains with 2 or more carbon atoms and a carboxyl group
Medium chain fatty acids
6-12 carbons
soluble at physiological conditions
Long chain fatty acids
13-20 carbons
generally insoluble
Very long chain fatty acids
> 20 carbons (also insoluable)
Simple Lipids
Include fats and oils
-comprised of 3 fatty acids each in ester linkage with a single glycerol (triacylglycerol)
-Make up the largest fraction (~98%) of lipids in animal feeds
Glycolipids
-esters of glycerol with CHO
-widely present in plants and major lipid component of forages
-in animals, glycolipids serve as markers for cell recognition and as energy sources
-maintain cell membrane stability
Phospholipids
-fats complexed with phosphoric acid
-water insoluable and water soluble regions
-critical for membrane function
-most abundant biological membranes