EXAM 2: Nitrogen Flashcards
aWhat does crude mean in crude protein
The word “crude” refers to the fact that not all nitrogen in most feed is exclusively in the form of protein.
what two ways can protein be studied/measured
quantitative perspective
qualitative perspective (profile of AA’s)
proteins serve as
structural elements of body
enzymes
hormones
carriers in blood
associated with genes
antibodies
proteins are comprised of _______% of dry, fat free body
80
about what percent of protein is in meats across species
18
Proteins contain C,H, and O. All proteins also contain___?
Nitrogen
Proteins contain C,H, and O. Almost all proteins also contain _____?
Sulfur
from the amino acids: cysteine and methionine
The average Nitrogen content taken is ______ for estimating the protein content of tissues and feedstuffs
16%
yield only amino acids or their derivatives on hydrolysis
examples: albumins, globulins, histones, protamines
simple proteins
simple proteins combined with a nonprotein radical
conjugated proteins
one or more protien molecules with nucleic acids
high in terms of seeds and glandular tissue and liver
ex. RNA
nucleoproteins
protein molecule and a substance(s) containing a carbohydrate group
ex. mucin in saliva
glycoproteins
protein molecule and a P-containing substance other than a nucleic acid or lecithin
ex. casein
phosphorprotein
protien molecule and a metal
ex. hemoglobin
metalloprotein
protein molecule and a lipid
ex. cell membranes
lipoprotein
consist of altered and degraded products of naturally occurring proteins
produced by the action of heat, enzymes, or chemical agents
derived proteins
end product of protein digestion or hydrolysis
building blocks for body protein
amino acids
how many amino acids are present in proteins
25
1 amino group
1 carboxyl group
neutral amino acids
more carboxyl groups than amino groups
acidic amino acid
more amino acid group than carboxyl groups
basic amino acid
the two sulfur-containing amino acids
cysteine
methionine
what amino acids are Monoamino-dicarboxylic (acidic)
aspartic acid
glutamic acid
what amino acids are diamino-monocarboxylic (basic)
arginine
lysine
citrulline
Amino acids and proteins are amphoteric. What does this mean
can be acidic or basic
dipolar ions
electrically neutral
zwitterions
what happened in 1870-1900
the proposal that amino acids were probably the building blocks of proteins
What did W.C Rose do in 1930’s
supplied all of the nitrogen to the animal in the form of amino acids
amino acids that must be contained in the diet consumed
there is 10 of them
dietary essential amino acids
amino acids that can be synthesized by the body at the rate adequate for normal growth
nonessential amino acids
what are the 10 essential amino acids
MATT HILL VP
methionine
arginine
threonine
tryptophan
histidine
isoleucine
leucine
lysine
valine
phenylalanine
What amino acids are readily synthesized by animal tissues
glycine
alanine
serine
aspartic acid
glutamic acid
asparagine
glutamine
proline
hydroxyproline
cannot by synthesized at a rate rapid enough to meet the body needs
essential amino acids
what two animals require the 10 essential amino acids listed for growth
dogs
pigs
For maintenance man only needs ____ amino acids
8
don’t need arginine and histidine
for growing humans they need ____ amino acids
10
for poultry how many amino acids are needed
12
the 10 essential plus glycine and serine
sparing effect
cysteine can meet half the requirement of methionine
tyrosine can meet half the requirement of phenylalanine
plants can utilize _______ and can __________ for each AA
ammonia
fabricate the carbon structures
Mammals lack the ability to
make approximately half of these carbon structures
Two aspects of protein nutrition (supply) of concern:
qualitative phase
quantitative phase
factors to consider when thinking protein quality
relative proportions of essential AA to meet animal needs
digestibility of these AA
rate of digestion
when you run out of 1st limited amino acid what happens
protein synthesis stops
feed conversion ratio
feed intake/ weight gain
if feed intake/ weight gain increases, is it good or bad
bad
feed efficiency
weight gain/feed intake
if weight gain/feed intake (feed efficiency) increases, is it good or bad
good
What are the two AA that is normally low
tryptophan
methionine
performance trial (including muscle and fat, also GI fill)
growth trial
measures how well the nitrogen absorbed is used
% of the actually digested N that is utilized
biological value
if you increase protein, you do what to the diet
increase the diet-induced endogenous loss
denaturation
modifying the molecular structure of a protein
protein losses biological function (active to inactive)
What are the two types of amino acid transporter
sodium-dependent
sodium independent
The process whereby an amino group (NH2) from an amino acid is transferred to a keto acid
transamination (aminotransfer)
means for detoxifying NH3
occurs in the liver
requires energy
essentially irreversible
krebs urea cycle
example of fairly poor quality
corn protein
High roughage diets are not conducive to _____
good utilization of NPN
what does NPN stand for
non-protein nitrogen
problems presently associated with the use of NPN
urea toxicity
decreased palatability
reduced performance
actually NH3 toxicity is due to the inability of the liver to conjugate to urea
urea toxicity
what are the recommendations for use of urea
no more than 1% of urea in the diet
no more than 33% of total ration N as urea
no more than 50% of supplemental N as urea
what are the two categories of Nitrogen sources
true protein
non-protein nitrogen
What are some examples of non-protein nitrogen
peptides, amino acids
nucleic acids
added NPN
when a plant is young, _____is high
NPN
when a plant is mature, _____is high
protein-N
how much of NH3 produced in the rumen is excreted in urine
10-15%
Terms for protein that escapes degradation in the rumen are
bypass protein
undegraded protein
escape protien
if the % of the undegraded portion is increased, then the availability of the protein directly to the animal is
increased
what are the factors affecting the extent of degradation
chemical nature of protein
retention time in the rumen
particle size
rumen pH
if heat treatment is increased, what happens to degradation
decreased
Examples of heat treatments include
pellet
roasting
extrusion
reasons to maximize microbial protein synthesis
increase amino acids in the small intestine
increase microbial growth, which increases fiber digestion
factors affecting microbial protein synthesis
available energy
available nitrogen
other nutrients
What allows ruminants to survive on very low-protein diets
nitrogen recycling
as protein increases in the diet, nitrogen recycling does what
decreases
forms of NPN
in feedstuffs
added (urea, NH3)
All NPN must go through _____ to yield _______
NH3, microbial protein
Factors that affect NPN utilization
nutrient balance of diet
frequency of feeding
the energy content of the diet
urea adaptation
increase in frequency, does what to ability to use urea
increase
Increase in energy density does what to urea utilization
increase
symptoms from too much ammonia
develops rapidly
uneasiness, discomfort
frequent urination
slobbering, bloat
tetany
_____ is an example of high quality, high soluble in the rumen
soybean meal
Utilization is influenced by the
nature of the rumen microflora
what is a prerequisite of maximal microbial growth from NPN
readily available energy source be present to provide the carbon skeleton
most NPN sources release____ very rapidly
NH3
if the carbon skeleton is not available, the NH3 is not utilized to make
amino acids
aromatic amino acids
phenylalanine
tyrosine
thyroxine
