Ruminal Protein Flashcards
Can animals be fed a diet adequate in protein but still be deficient in some amino acids?
Yes it is possible
How are amino acids classified?
by their R group
Structure of amino acid
Amine (-NH3)
Carboxyl (-COO)
R group
What makes an amino acid essential? Non-essential?
Essential: cannot be produced in sufficient quantities to meet needs
Non-essential: can be produced sufficiently
Which amino acids are essential?
Phenylalanine
Valine
*Threonine
*Tryptophan
Isoleucine
Methionine
Histidine
*Arginine
Leucine
Lysine
What 3 maintenance functions are amino acids needed for?
- Endogenous urinary N (amino acid pool)
- Replace scurf
- Replace metabolic fecal N.
What is scurf? What is metabolic fecal nitrogen?
Scurf = proteins lost from body surface
Metabolic fecal N = proteins lost from undigested digestive secretions (enzymes/mucus) and fecal bacteria
What animals require the most CP?
Calves and lactating dairy cows
What is the most ideal amino acid source for ruminants?
“true” protein
What are some examples of true protein?
proteins, peptides
What are some examples of non-protein nitrogen?
Urea, ammonia, nitrates, nitrites
Urea is __% N
44%
What is the difference between RDP and RUP?
RDP: used by microbes (incorporated into cell or deaminated)
RUP: escapes rumen bacterial degradation
What factors affect microbial CP degradation?
- stage of plant growth (mature less degradable)
- cross linking of peptide chains
- Seed coat
- Chemical nature of proteins
- Rumen pH
- Heat
- mineral chelation
How does 3 dimensional structure of a protein affect degradability?
differences in solubility and how well it unravels
Isoelectric point
pH where proteins are least soluble
How does heat affect protein degradability?
- reduce trypsin inhibitors
- increase escape
- maillard reaction of aldehyde with NH2 of protein
How does source of carbohydrate effect ruminal amino acid fermentation?
What is the fate of ammonia produced in the rumen?
- Eructated
- Made into urea by the liver
What is the fate of ammonia after it is absorbed?
- makes amino acids that go into the blood pool
What is nitrogen recycling and what is the benefit for ruminants?
ammonia recycled back to rumen
Benefit is it serves as N for microbes when protein consumption is limited
When would it be beneficial to supplement dairy or beef cattle with RUP and/or protected amino acids?
may be beneficial for calves or dairy cows
