animal feed processing

1. Feed Processing
Lecture 9
ANS 336
2/9/2001

2. Processing
• To Make a profit
– Reduces cost by improving feed efficiency
– Improve production from better utilization
– Increase intake
• To alter particle size
– Easier to consume – pelleting, cubing
• Range feeding, reduce fines, reduce selection, improve handling
efficiency.
– More digestible

3. Purpose of Processing
• To Change moisture content
– To make is safe for storage, improve
palatability, more digestible, to prepare for
other processes. (steaming, rolling,flaking)
– Two ways to remove moisture
• Aeration with heat
• Aeration without heat
– For safe storage
• Hay (loose) 25 %
• Baled 20-22 %
• Chopped 18-20 %
• Cubes 16-17 %

4. Purpose of Processing - Moisture
• Addition of water to ensile grains
– Best at 30 % moisture
• Addition of water to rations to improve
palatability and improve mixture
uniformity.
• Improve intake
– High ambient temperature.

5. Purpose of Processing
• To change density (weight per unit of
volume)
– Reduce transportation charges
– Bulky to control intake
– Increase density to increase amount consumed.
• Dairy cows increased energy and protein needs in
transition period but reduced intake.
– Flaking reduces density but improves surface
area of the grain for improved digestibility.

6. Purpose of Processing
• To change Palatability (acceptability) hence
feed intake.
– Adding to improve: molasses, flavors, fats
• Adds nutrient content while improving intakes
– Adding to limit consumption: salt
• Palatable in limited quantities but in excess very
limiting.
• Animals on pasture or range need limiting factor on
free choice of minerals and some feeds

7. Purpose of Processing
• To change nutrient content
– Adding Iron
– Milk fed over an extended period of time
• Adding vitamins
• Antibiotics
• Fats
• Protein
– Sugar coating cereal

8. Purpose of Processing
• To increase nutrient availability and
digestibility.
– Milo, rolled, dry ground or not processed has
close to the same nutrient content of Corn.
• Less available - starches represent 70-80% of the
total dry matter appears to less available in milo
than other grains.
• By hydration or rupturing of the starch molecules
more of the starch appears to be digestible giving
better results in digestion trials.
– Processing increases surface area for microbes
and digestive enzymes. Improves utilization.

9. Purpose of Processing
• To detoxify or remove undesirable ingredients.
– Cottonseed – Gossypol
• Adding iron salts: rupturing of pigment gland
– Soybean meal
• Heat – deactivates trypsin inhibitor
– Linseed meal
• Water -Crystalline water soluble substance
– ? Sweet Clover – spoiled or moldy
• Dicoumarol – anticoagulant, causes internal bleeding
– Manufactured form called Dicumarol

10. Purpose of Processing
• To improve mechanization
– Baling
– Chopping
– Cubing
– Ensiling
– Round baling
– Transportation
– Storage
– Self feeding
– Push button feeding

11. Purpose of Processing
• To lessen molds, salmonella and other
harmful substances.
– Aflatoxins
• Mycotoxins – carcinogens result of molds growing
in grains
• Ammoniated feeds – Cottonseed
• Ammonia added to hay stacks.
– Propionic and acetic acids reduce or inhibit
mold growth.
• Added at harvest

12. Purpose of Processing
• To enhance rumen function (chemical, buffers, by-
pass)
– Heat or pressure treated
• Protected or escape protein
• Treatment with tannins
• Formaldehyde or other aldehydes
• Lipids
• Complexing with bentonite clay
• Use of AA analogs (proteins)
• Adding ionophore- Monensin (Rumensin)
– Changes rumen fermentation patterns
– Shifting of VFA and methane production
– Changes passage rate of particulate matter
– Slow release NPN
– Buffers – passage rate versus rumen pH

13. Methods of Processing
• 70-80 % of the dry matter in Concentrates is
composed of Starch.
– Therefore, processing methods have as their
primary objective; to improve the availability of
these Starches to improve feed efficiency and
digestibility.
– Steam Flaking is the standard – everything is
measured to that standard
• First process that showed a major increase in feedlot
performance

14. Types of Processing
• Dehulling – (Decortication)
– Removal of outer-coat of grain
or nut.
– Hulls high in fiber, low in
digestibility for monogastrics.
– Used as fiber source in
Ruminants.
– Cottonseed Hulls
– Soybean Hulls
– Can vary protein levels in
CSM, SBOM by the amount
of Hulls removed.
– Undecorticated seed has about
22% protein – Decortication
can increase amount of protein
to 60%
• Hulls low in protein, high in
fiber.
• Extruding –
(Gelatinization)
– Feed is pressed, pushed, or
protruded through
constrictions under
pressure.
– Grinding, heating with
steam then forced through a
tube by an auger.
• The holes are cone shaped
from smaller to larger
allowing the feed to
expand causing disruption
of the starch molecules.
– Improved feed efficiency
Milo by 15% over dry
rolled Milo in Feed lot
trials.

15. Types of Processing
• Grinding
– Reduces particle size by
impact, shearing, or
attrition.
• May change digestibility
of cellulose and protein.
– Hammermill
• Hammers to decrease size
until it passes through a
screen.
• Desirable when pelleting
follows. Weed seed
present.
– Called Mash or Meal
– Mash – poultry
– Meal four footed animals
– Economical but depends on
power, speed screen size
and type of grain.
• Rolling
– Dry – cracking or
crushing of grain by
steel rollers.
– Steam
• Crimping
• Expose grain to steam
for 1-8 minutes before
rolling.
• Does not improve feed
efficiency over
grinding.
• Increases palatability
and animal acceptance.
Reduces fines.
• May add up to 6 %
moisture to grain.

16. Types of Processing
• Heat treatments
– Excess destroys nutrients –
Protein, vitamins
– Done properly – increases
nutrient availability. –
• Destroys trypsin inhibitor in
Soybeans
• Improves rate and efficiency
of gains through partial
gelatinization of protein.
• Improves availability of fats
and AA. Increases ME
– Must be done properly.
• Does not improve for
monogastrics but does for
Ruminants.
• Dry heating
– Micronizing
• Heated to 300º F by gas
fired infrared generators as
it passes on a steel plate
then dropped into rolls.
(7% moisture).
• Densities between 18-30
lbs per bushel.
• 25 # recommended.
• Cheaper than steam
rolling.
– Popping
• Milo - Density problem
with reduced feed intake.

17. Types of Processing
• Roasting
– Corn and Soybeans
• Increase availability of
starches and proteins
– Soybeans
• Improves feed efficiency
and gains by 10 % over
ground corn.
• Fats - higher content in
raw beans.
• Greatly increases
availability and value of
protein for monogastrics.
– Hogs fed whole cooked
beans have a softer carcass.
Value added ?
– Expensive equipment-
requires long term
investment.
• Cooking
– Fitting beef cattle.
– Hogs
• Potatoes, beans, soybeans
– Garbage – decreases
nutrient availability but also
destroys Trichinella which
causes trichinois in humans.
– Reduces selection by hogs.
– Destroys proteins.
– Trichinois: If pork is
properly cooked - no
problem with transmission.
But incidences are higher in
areas where garbage is fed
to hogs.
– All states require
commercial garbage fed to
animals must be cooked.

18. Types of Processing
• Exploding
– Swelling of grain under
pressure then releasing of
the air.
• Grain put into steel
“bottles” steam injected
into the bottles to 250 psi
for 20 seconds then
released.
• Forces moisture into the
grain.
– Becomes expanded balls
with hulls removed
– Product similar to puffed
cereal.
– Compared to Steam flaking
of Milo in animal response.
• Flaking
– Modification of steam
rolling by increasing the
amount of time steam is
applied or by the amount of
pressure.
– Milo responds the best.
– Preferred method for
horses. – Fluffy - produces
fewer digestive problems
– Flaking influences the
density of the feed
– Results depend on:
Steaming time, temperature,
grain moisture, roller size
and tolerance, processing
rate, type and variety of
grain.

19. Types of Processing
• Pelleting - Cubing
– Compacting and
forcing through dies.
• Facilitates
mechanization
• Eliminates fines.
Increases palatability
• Alleviates separation of
ingredients and sorting.
• Increases feed density.
– Reduce storage space
– Transportation costs
– Popular amount horse
owners.
• Pelleting - Cubing
– May destroy Vitamin
A, E, and K if
insufficient
Antioxidants for
processing.
• Pellegra (nicin
deficiency)does not
exist in Mexico despite
their high corn based
diets.
– Limewater is added
to the corn meal in
making tortilla. Lime
water releases
nicotinic acid.

20. Types of Processing
• Crumbling
– Pellets crumbled
• Feed additives.
– Terramycin crumbles
• Bran Mash
– Steamed wheat bran
– Traditional feed for horse
on idle days.
• Watered Feeds
– Mixing water with feeds to
make a gruel, slurry, or
swill.
– Mixing, Whey with wheat
screenings
• Blocks
– Mineral supplements
– Fat supplements
• High energy blocks
• Up to 500 lbs in size for
long term use.
• Hardness, salt and fat
content will help limiting
intake to about 2 lbs per
day.
• Lessens labor
requirements for range
cattle.
• Alleviates losses from
feeding on ground or from
wind.

21. Types of Processing
• Feeding whole corn
– Under six months of age
calves masticate enough to
process the whole kernels.
– Roughage to concentrate
ratio seems to be important.
– Whole kernels in the grain
cause concern. However,
ground corn passes through
also but is fine, therefore,
not seen.
– Animals on high
concentrate diets show very
little improvement from
processed ground grain.
May not offset processing
cost.
– Hogs and poultry not a
problem.
• When mixing or
processing feeds - Be
cautious.
– Prior feeds processed
can leave residue.
– Additives are usually
extremely potent.
– Customers can be
easily lost over
unintentional mixing of
the wrong ingredients.

22. Types of Processing
Animal Waste Processing.
• Poultry waste
• Broiler and layer litter has
been used for many years.
• High nitrogen content.
• Types of processing
– Deep stacking
• Several weeks for
increased temperature to
160º F growth stopped at
80 º F and killed at 145 º F.
– Used successfully for many
years
– No documented animal
health problems.
– Ensiling (fermentation)
• CHO are converted to lactic,
acetic and other acids
• Heat is generated killing
pathogens
• Nutritive value is improved
by blending with other feed
ingredients such as cereal
grains prior to ensiling and
adjust to 40% moisture.
• Residues from medicines and
minerals may not be affected
by ensiling Be cautious.
• No disease problem from
ensiling. Problem ?

23. Types of processing- Adding Fats
• Increases Caloric density
of ration
• Improves palatability
• Facilitates absorption of
Vit. A and D
• Supplies Linoleic acid
– Animal body requires
Linoleic acid – all species.
Ruminant microbes can
synthesis.
• Delays hunger.
– Fats require longer period
in the stomach that CHO
and protein. “Sticking to the
ribs” in Human diets.
• Controls dust and fines
• Lubricates equipment
– Coats and clogs equipment
if in excess.
• Solidify in cold weather.
• High levels cause pellet to
be soft.
• Fats can become rancid.
• Added at the levels of:
– 5-10 % swine and poultry
– 2 – 6 % in ruminants
– Lower consumption if
exceeded.
• Ethoxyquin – effective
antioxidant.

24. Types of processing- Adding Fats
• Degree of unsaturated Fats important in
availability of Vitamins.
– Digestibility decreases with saturation.
– Relationship between degree of saturation and
type of body fat formed. Especially in
monogastrics.
– High levels of unsaturated fats produce soft
pork.
– Cappuccino machines in dairy cows.

25. Types of Processing
• Molasses – 5- 15 % of
diet it has about 75 %
energy value of corn.
• Appetizer and controls
dust.
• In humid conditions
should be limited to 5 %
of ration as mold can
develop.
– Addition of Calcium
propionate can control
mold.
• Organic preservatives
– Propionic and Acetic at 1 to
1.5 % at time of harvest to
inhibit molds and bacteria.
• Treatment of High-
cellulose feeds.
– Rice, barley, oat straw;
bagasse; tree bark; corn
cobs;gin trash; newspaper;
and seed hulls.
– In their natural state are
poor feedstuffs because of
lignin or silica or a
combination of the two
encrust the energy-rich
CHO, cellulose, and
hemicellulose and keeps
microbes from breaking
them down to release the
energy.
– Must open up to permit
digestion by microbes

26. Types of Processing
High Cellulose Feeds cont’d
• Chemical treatment
– Alkali – sodium hydroxide,
calcium hydroxide,
potassium hydroxide.
– Increases digestion of cell
walls
– Increase energy digestibility
by 10%
– Decreases nitrogen
digestibility through heating
effect. Therefore improved
performance with added
protein sources.
– Used during WW I in
Germany when critical
shortages of animal feed
occurred.
• Ammoniated
– Air-tight enclosure and
adding anhydrous ammonia
or liquid nitrogen.
– 3.0-3.5 % anhydrous and
take about 20 days.
– Adds NPN
– No mineral residue such as
chemical.
– Increases CP by 3- 10 %
– Increases TDN and DE by
3-23 %
– Increases animal intake
– Prevents molding.
– Dangerous to use – very
toxic

27. Types of Processing
High Cellulose Cont’d
• Hydrogen Peroxide
– Residue pH is brought up to 11.5 becomes mushy, then
rinsed off and dried.
– Can be used wet but quick.
– Has better feed values than corn silage.
– Right now; tooooo expensive and a patent is pending on
the process.
– Requires a lot of water.
• High pressure steaming
– Used with and without chemicals
– Aspen (wood) has been shown to have digestibility of
up to 56%.
– Sheep consumed at 60% of the ration.
• Normal body weight gains and carcass traits.
• Cost is high - Use in situations of high feed cost

28. Types of Processing
• Total Mixed Rations
– Makes greater efficiency in feeding and lessens sorting
at feed bunk.
– Forces consumption of ingredients not highly palatable.
– Can limit concentrate consumption
– Easier to get animals on full feed.
– Easier to automate
– Provide better control of nutrient intake
– Species involved.
• Dairy
• Beef Feedlot
• Sheep
• Chickens
• Swine

29. Summary
• We process to improve profitability,
increase mechanization, utilize poorly
digestible feed stuffs.
• To improve rates of gain
• To improve the number of animals each
person can handle.
• To utilize products that animals would not
normal consume.