exam 5: New material Flashcards
various non-nutritive substances are
added to a ration to
- stimulate growth or other types of performance
- improvement of feed utilization or feed efficiency
- improving the health of the animal
general info on types of feed additives
-some have demonstrated situation-specific responses while others are universal
-Factors other than bio-efficacy considered relative to the use of an additive: cost, toxicity, tissue residues.
-In general, most feed additives produce their response in young, rapidly growing animals. There is seldom any benefit in mature animals (buffers and thyroprotein compounds being two exceptions).
what are the two exceptions of feed additives that are beneficial to mature animals
buffers and thyroprotein compounds
Most common use of nonnutritive additives are as:
antibacterial agents
hormones and their derivatives
others (buffers, antioxidants, enzymes etc)
what are the two main examples of antibacterial agents
antibiotics
sulfa drugs
examples of feed additive classifications
Medications
Antioxidant
Antifungal Agents
Enzymes
Herbs
Pellet Binders
Surfactants
Pigments
Direct‐Fed Microbials
Essential oils
Fermentation
Products
Flavors
Stool Conditioners
Buffers
feed additive: general modes of action
Sub-therapeutic antibiotics:
Decrease sub-clinical infection
decrease growth depressing microbial metabolites
decrease gut maintenance (turnover and inflammation)
decrease competition for nutrients
what do plant extracts do
–Varied physiological functions
–Antimicrobial
–Altered mucin production
–decrease intestinal “turnover”
what do probiotics do
–specific pathogen(s) exclusion
–Immunological modulation
–Improved nutrient use
–Antimicrobial action (pH ↓ &
bacteriocins)
antimicrobial agents and anthelmintics are defined as ________ by the Food and Drug Administration (FDA)
drugs
FDA regulates the ______________ of antimicrobial agents and anthelmintics
usage levels
allowable combinations
periods of withdrawal prior to slaughter
a compound synthesized by a living organism that inhibits the growth of
another organism.
antibiotic
It is well-recognized that antibiotics effective in
improving the performance of animals has one thing in common, ______________________________.
their ability to suppress or inhibit growth of certain microorganisms
how are antibiotics absorbed
readily absorbed into the vascular system of the host animal
others are hardly absorbed at all
Levels fed: general performance enhancement
low levels of 5-50 g/ton
Levels fed: disease prevention levels
50-200 g/ton feed
Levels fed: therapeutic levels
200-500 g/ton
Aimed at the control of respiratory diseases, and diarrhea
particularly useful for short-term treatment of the entire group of animals.
effects of antibiotic feeding
- Animals responding to antibiotic feeding consume more feed than controls, gain weight faster, and thus less feed is needed per unit of gain
- Reduced morbidity (sickness)
- Reduced mortality (death)
- Reduced incidence of secondary infections,
dehydration, pneumonia, etc.
effects of antibiotic feeding specific to feedlot cattle
best benefit to young, stressed calves arriving to feedlot
also cattle that have been mismanaged
feeding antibiotics reduces the incidence of liver abscesses of high grain rations for feedlot cattle
effects of antibiotic feeding specific to dairy cattle
does not increase milk production
high levels of antibiotics to lactating dairy cows are prohibited by law as there may be residue into the milk
Antibiotics are drugs, not nutrients, and thus their
effects upon the nutrition of animals must be _______
secondary
The mode of action of antibacterial drugs
appears complex and there are at least three plausible populations (assumptions):
what are the three assumptions
- Metabolic effect– drug affects various enzyme systems like phosphorylation
- Nutrient sparing effect– via altered microbial
composition of the G.I. tract - Disease control– benefits from suppression or control of subclinical or non-specific diseases
Nutrient sparing effect- via altered microbial
composition of the G.I. tract wherein the antibiotic
may:
a. stimulate microorganisms in the G.I. tract which
favor nutrient synthesis of a critical nutrient(s)
b. suppression of organisms that compete with
the host for dietary needs
c. improved nutrient absorption resulting from
thinner, healthier intestinal walls for antibiotic fed
animals.
what are some societal concerns regarding antibiotics
are they less effective?
does feeding them pose a public health threat?
In considering the possibility that feeding antibiotics
to animals might cause a threat to public health, the
reasoning is:
- antibiotic-resistant strains of nonpathogenic
bacteria with transferable resistant (R) factors
emerge in the intestines of the animals being fed
the antibiotics - These R factors may be transferred to the animals’ virulent (toxic)bacteria.
- These virulent, antibiotic-resistant bacteria are
passed on to man. If this transfer of resistance is occurring, then the areas where people are working with animals should show the most resistance
Presently available growth promoting hormones or their derivatives include:
MGA
Synovex
Ralgro
DES or diethylstilbestrol
Bovine SomatoTrophin (BST)
Injectable growth hormone approved for increased
milk production in dairy cattle. Altered nutrition and
management are required with this product.
Bovine SomatoTrophin (BST)
A synthetic estrogen that was used for about 18 years in the cattle industry before its removal in 1972 from the market.
DES or diethylstilbestrol
A brand of zeranol (the active component is resorcyclicacid lactone - a product isolated from a type of corn mold)
Acts like an estrogen
response is best with high quality rations
Ralgro
200 mg progesterone + 20 mg of estradiol benzoate
S Synovex
200 mg testosterone + 20 mg of estradiol propionate
H Synovex
This implant is sex specific.
Generally increases of 10-15% in average daily gain and similar savings in feed have been observed.
Synovex
synthetic progestogen
This compound when fed orally to feedlot heifers
suppresses estrus and appears to promote growth.
MGA
MGA appears to promote growth, a portion of
this weight increase may be due to ____________in a manner similar to the effects of ____________ on
certain women.
water retention
birth control pills
A re-partitioning agent fed for a period of time before slaughter
directs nutrients more toward protein deposition and away from fat deposition.
beta-agonists
most common beta-agonists
ractopamine
The great amount of interest in this area is based on
the fact that about 10% of the total energy intake of the ruminant is lost as methane in the functioning rumen.
This represents a major loss for productive purposes.
methane inhibitors
The great amount of interest in the area of methane inhibitors is based on the fact that about 10% of the total _______ intake of the ruminant is lost as ________in the functioning rumen.
This represents a major loss for productive purposes.
energy
methane
The_______ must be matched to the substrate.
enzyme
with regards to enzymes, there may need to be some protection from certain ___________________
GI environmental factors
Problems can be encountered in shifting ruminants
from a high roughage diet to a high concentrate diet can require________
buffers
indicators of a need in increased buffering capacity following rapid intro of highly fermentable CHO source:
less chewing/cud= less saliva=less bicarbonates being returned to rumen
high acid production from VFA’s
the inability of microorganisms to shift rapidly with a build up of lactic acid causing pH to decline
faulty mineral rations
indicators of a need in increased buffering capacity following rapid intro of highly fermentable CHO source:
less chewing/cud= less saliva=less bicarbonates being returned to rumen
high acid production from VFA’s
the inability of microorganisms to shift rapidly with a build up of lactic acid causing pH to decline
faulty mineral rations
Studies with the use of buffers in dairy cows indicate they may be beneficial in at least three instances:
- using ammonium chloride in prepartum cows for reducing milk fever
- low milkfat problems
- sudden ration shifts
Antibiotics may be effective at times as ______________________, their efficacy wears off with
continued usage.
bloat controlling agents
Surface active agents have shown considerable promise for control of __________provided a relatively regular intake can be obtained
pasture bloat
a relatively inert montmorillonite clay which is often used as a pellet binder
bentonite
Work with pigs has demonstrated clear benefits to the addition of 0.5%______________ to diets containing aflatoxin.
bentonite
Fed at the rate of 5% of the diet for the purpose of
reducing the recycling of such pesticides as dieldrin
and DDT in dairy cows.
activated carbon
Many pesticides are recycled via the________
bile
if_____________ is fed much of the excreted compounds may be adsorbed and passed out of the body.
activated carbon
examples of other additives
activated carbon
bentonite
bloat control compounds
buffers
enzymes
methane inhibitors
beta-agonists
the most promise of the use of thyroid active hormones like thyroxine and thyroproteins/ simulated thyroproteins (iodinated casein) has been in
lactating cows and ewes
simulated thyroprotein example
iodinated casein
mold products
antibiotics
mycotoxins
molds protect their food by secreting
mycotoxins
toxic metabolites of filamentous fungi (molds)
mycotoxins
myco means
fungus
toxin means
poison or toxicant of fungal orgin
diseases produced by mycotoxins
mycotoxicoses
disrupting cell membranes, protein/DNA synthesis
cytotoxicity
more than ____ molds produce toxins, _____ mainly toxic for animals
100
13
Mycotoxins are more common in _______________ than in animal products
cereals and oilseeds
a diverse group of compounds that are toxic to animals and produced by actively growing filamentous fungi
mycotoxins
molds are _________ organisms
aerobic multi-cellular
mold growth requires _____ available water than bacterial growth
less
do all molds produce mycotoxins
NO
mycotoxins are __________ metabolites of mold growth
secondary
general effects of mycotoxins: toxin-dependent, dose-dependent
feed refusal
digestive problems
nervous system problems (staggering)
reproduction (conception to abortion)
immune impression
organ damage
teratogenic (embryo malformation)
carcinogenic
death
Important mycotoxins in the US: Aflatoxins
Aspergillus flavus
A. parasiticus
Important mycotoxins in the US: Zearalenone
Zea maiz
Fusarium roseum
F. monliniforme
Important mycotoxins in the US: Trichothecenes
T-2 toxin (Fusarium tricinctum)
Vomitoxin/DeOxyNivalenol (DON)
Important mycotoxins in the US: Fumonsin
Fusarium moniliforme
Important mycotoxins in the US: Ochratoxin
A. ochraceous
Penicillium viridiactum
Factors Contributing to Aflatoxin Formation
Storage conditions (humidity)
Grain humidity (>13%)
Water stress (drought years, wet harvest)
Insect damage (in the field or storage)
High temperatures (90º F during a critical time of development)
Plant variety
Planting density
Soil fertility (soil Ca / peanuts / aflatoxin)
Late planting date: late harvest date
Black sclerotia _________caused by Claviceps purpurea infection_________
ergots
barley
One of the most potent carcinogens (liver, kidney, urinary system, intestine, lung)
Attacks vascular system: hemorrhages (Vit K may
teratogenic
aflatoxin
Insects function as vehicles for _______________
transmission of fungi
Mycotoxins & Moulds Occur in Most Feeds
including
grain
hay
silage
types of aflatoxins include
B1
B2
G1
G2
M1
aflatoxin: B1
most hepatotoxic, carcinogenic and
prevalent
aflatoxin: M1
aflatoxin metabolite in milk (1-2% of dietary
level)
Acute primary mycotoxicoses
High [toxins]
Hepatitis (inflamed liver)
nephritis (inflamed kidney)
necrosis of epithelium
death
Chronic primary mycotoxicoses
Lower [toxins] over a longer period of time
Detriments growth performance
Secondary mycotoxic diseases
Even lower [toxins] than chronic primary
Immunosuppression
The more aflatoxins present in the guinea pigs liver caused what to happen
increasingly pale livers with increasing doses of aflatoxins
An enlarged ________ was present in a mouse given an intraperitoneal injection of zearalenone.
uterus
ways to prevent Mold Growth in stored grains
Ammoniation
organic acids
salts of organic acids
most effect methods to prevent mold growth is
ammoniation
examples of organic acids
propionic (1%)
acetic
sorbic
benzoic
examples of salts of organic acids
calcium propionate
potassium sorbate
ways to reduce Aflatoxin content
Mechanical screening (separating grains)
Chemical inactivation: Ammonia, methylamine,
sodium hydroxide, formaldehyde, HCl, H2O2, NH3
Propionic acid (1%)
Heating: not effective
Blending (not for sale: prohibited by FDA)
Dietary Manipulations to Alter Response to
Mycotoxins
organic and inorganic binders
examples of inorganic binders
***or mineral clays
bentonite
zeolites
Hydrated Sodium Calcium AluminoSilicates (HSCAS)
examples of organic binders
dehydrated alfalfa meal
Cell wall carbohydrates from
yeasts (Saccharomyces cerevisiae)
Increase Plane of nutrition (protein, energy and vitamin contents)
organic binders
liver tumor from rat was present after given
aflatoxin
oral lesions and decreased growth in turkeys
abomasal ulcers in calves are all due to
T-2 mycotoxin
why do we add feed additives
to ensure our animals can better utilize/absorb their feed because naturally the process of absorbing is not 100%
buffer and thyroprotein always make a positive or negative result?
positve
thyroprotein is related to what kind of metabolism
energy
importance of activated charcoal
helps prevent poisoning of DDT
less that 1% of the diet
most effective enzyme
phytase
direct feed microbials are known as what
probiotics and prebiotics
probiotic vs. prebiotic
post:
-good bacteria (lactobacilli bact.)
-target small intestine
-exclude bad bacteria
pre:
-target large intestine
-resistant CHO/starch (not broken by stomach HCl)
-food for good bacteria
major process in feed manufacturing
ingredients recieving
grinding
batching and mixing
conditioning and pelleting
causes of weighing variation
hand-weighing ingredients
micro-ingredients and premix dose errors
discrepancies between call size and scale resolution
mixer uniformity evaluation: <10%
excellent
no corrective action
mixer uniformity evaluation: 10-15%
good
increase mixing by 25-30%
mixer uniformity evaluation: 15-20%
fair
increasing mixing by 50%
look for worn equipment
overfilling
sequence of ingredient addition
mixer uniformity evaluation: +20%
poor
possible combination of all corrective actions for fair rating
consult extension personnel or feed equipment manufacture
what type of mixer takes the longest dry/wet
vertical
what type of mixer takes the least time dry/wet
twin shaft paddle
batching equipment
micro bin system
tote bag system
scales (micro/macro)
weigh buggy
batching and mixing objective/goal
accurate weighing of ingredient
minimum batching time
production of feed with uniform distribution
advantages of roller mills
low energy consumption
less noisy
less heat production
less moisture loss
uniformity of particle size
disadvantages of roller mills
investment cost are high
complicated operation
high maintenance cost
grinding issues
strict cleaning requirement
advantages of hammermills
produce wide ranges of particle sizes
handle friable material/fiber
cost of purchase is low compared to roller mills
low maintenance cost
easy to operate
disadvantages of hammermills
less uniform particle size
high energy usage
generates lots of heat
noisy
high potential for dust pollution
when will roller mill technology may not be feasible
when product is not friable, fragile or breakable
high fiber/moisture
no value from maintaining a uniform particle size with minimal fines
grind size is controlled by
number of roll pairs
roll gap
roll speed
corrugations
corrugation number
particle size is controlled by
screen size
hammer tip speed
air assist system
hammer setting
hammer pattern
particle size is related to _______________ operations
hammermill
grind size is related to _______________ operations
roller mill
environment and safety factors regarding roller mill
less dust
lower noise level
environment and safety factors regarding hammermill
requires dust control (bag house air permit)
high noise
rise of fire and explosion
maintenance cost regarding roller mill
re-corrugation
freight cost (location of shop vs feed mill)
routine gap adjustment higher maintenance time (daily particle samples)
maintenance cost regarding hammermill
screen replacement
hammer replacement
minimal maintenance time
grinding equipment factors to consider (categories)
grinding capacity requirement
energy consumption
maintenance cost
environment and safety
less than 400 microns
fine particle
400-700 microns
medium particle size
greater than 700 microns
coarse particle size
info on warehouse
ingredients and totes are stored on racks
first in/first out ingredient rotation
FIFO stands for
first in-first out
the grinding operation does what
increase surface area
enhance energy and nutrient digestibility
functions of grinding
achieve proper/uniform particle size
improve the efficiency of pelleting operation
improve feed quality
maintain the desired physical characteristics of feed like flowability and limiting dust
receiving center equipment includes
scales
unloading mechanism
receiving hopper/conveyors
cleaning/screening devices
elevator legs
what makes up the unloading mechanisms of receiving center equipment
truck dumper
hopper bottom trailers or RR cars
mechanical scoops
front end loader for barges
what makes up the cleaning/screen devices of receiving center equipment
magnets
grain scalpers
grain cleaners
receiving center ingredients terms
unprocessed grains
processes bulk ingredients
soft feed ingredients
heavy feed ingredients
liquids
micro-ingredients
why is heating not effective to reduce aflatoxin
by the time you reach a temp to kill it you are causing your products proteins to denature
ruins product
ammoniation
treatment/reaction with ammonia
the most hepatotoxic aflatoxin
B1
what are these structures
aspergillus toxins: aflatoxin
teratogenic
Substances that cause congenital disorders in a developing embryo or fetus
aflatoxin is prevelent in
southern section of US
Zearalenone,DON (Vomitoxin) are prevelent in
northern US
Ergotamine is prevelent in
northwest US
Tremorgens are prevelent in
western US
Ochratoxin are prevalent in
eastern US
what do beta agonist do
A re-partitioning agent fed for a period of time before slaughter
directs nutrients more toward protein deposition and away from fat deposition.
