Tim 1 Flashcards
6 reasons why the rumen is an ideal fermentation chamber
Anaerobic
85-90% moisture content
38-40C
pH control
Removal of products
Constant supply of food
3 phases of rumen
Gas
Rumen malt (solid zone)
Liquid Zone
In what phase are the majority of microbial organisms found?
Solid
What type of diet gives you good stratification?
High forage
How are bacteria classified in rumen?
Based on prefered substrate
2 major advantages of pre-gastric fermentation?
Make better use of fibrous roughages
Can convert cheap non-protein nitrogen into high quality microbial protein
What increases as grasses and straws get older?
Cellulose and lignin will increase
4 major carbs fermented by rumen?
Cellulose
Hemicellulose
Pectin
Starch
3 main non-protein nitrogen sources
Urea
Nitrates
Ammonia
What are fermented forages high in?
Ammonia
how much nitrogen do proteins on avg contain?
16%
what does ammonia production from nonproten nitrogen support?
Microbial protein production
Why do we generally not add urea to lactating cows?
Fermented forages are high in ammonia
High amounts of urea can make feed unpalatable
What adds up to equal metabolizable protein?
Microbial protein + bypass protein = Metabolizable protein
Can protozoa utilize ammonia for growth?
No, they utilize A.A. or eat bacteria
What makes up NDF
What makes up ADF
- Cellulose + hemicellulose + lignin = NDF
- Cellulose + lignin = ADF
What part of the cell was is unavailable?
Mostly lignin - unfermentable
What do you want to match so that you have most efficient microbial protein production?
Protein degradation and CHO fermentation. Otherwise if protein degrades to rapidly you get a spike in ammonia which you lose to the blood
Contents of lysine and methionine in most feedstuff inferior to bacterial protein
6 factors affecting rumen microbial protein production
Available Energy
Rumen Ammonia levels - very importnat
Synchronization of fermentation (CHO/N)
Preformed amino acids/peptides
Other nutrients
Rumen environment
Why are multiple feedings/day prefered?
You get less loss and less lacking therefore more efficient with ammonia
Functions of rumen protozoa?
Participate in cellulose digestion - greater VFA production
Highly proteolytic - provide ammonia to bacteria
Slower fementation of starch and sugars
Remove O2
How to remove protozoa?
Chemicals
Isolation
Feeding high concentrate diets
Feeding unsaturated fatty acids
2 benefits of supplying bypass protein
Maximize rumen microbial protein production
High-producing ruminants - microbial protein inadequate
2 ideal feed stuffs to provide bypass protein
Corn gluten meal
Soy bean meal
How does particle size affect degradation?
Smaller the particle size the higher the SA the more degradable it is
What do high grain diets cause?
Acidosis - decrease in proteolytic activity
How can you alter B1 and B2 so that they are not as degradable in rumen?
Heating, Roasting
- Alters protein structure and solubility
WHat occurs if you decrease solubility of a feed?
Decrease solubility in rumen, increase bypass protein
How can Heated Soy Bean affect milk yield?
Heated soy bean increase byepass protein which increase milk yield
HOw does chemical treatment affect protein degradation?
Crosslinks are formed, which decreases solubility
3 major factors of ammonia absorption from rumen?
Rumen NH3 levels
ATP supply
Rumen pH - more alkaline pH, more absorption
Fate of absorbed ammonia
Transported to liver by portal vein
Converted to urea
Urea released into blood
Ammonia Toxicity
What affect does high forage content have on urea produced?
Higher the forage content, higher the urea
3 ways that urea is transfered into rumen
Saliva
Simple diffusion across wall
Urea transporters
3 inputs of N into the rumen?
Dietary Protein - Protein N and NPN
Recycle Urea - Saliva and Rumen Wall
Microbial protein
3 outputs of N from the rumen
Microbial Protein
Undegraded feed (bypass) protein
Ammonia Absorption
