Lecture 1

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Concentrates
Feeds & Nutrition
AN S 336
Chapter 10
Introduction

All biological processes require energy
– Respiration, Temperature Regulation, Motor
Control, etc.
– Production

Production
– Parameters we as producers are seeking from our
livestock
– Lactation, growth, pregnancy, egg laying, etc.
– Require large amounts of energy
Introduction

Production cont’d
– Before energy is expended for production, energy
requirements for routine body functions must be
met
– Therefore, producers must utilize a high energy
ration when feeding
• High caloric density and digestibility
– A balanced high energy ration will allow for
livestock to reach their genetic potential for
production with a minimum amount of feed.
Concentrates


“Feeds that are high in nitrogen-free extract
and total digestible nutrients (TDN) and low
in crude fiber (less than 18%)”
NFE
–
–
–
Term for organic material in a feedstuff for which
there is no specific analysis.
These include carbohydrates, pigments, and
water soluble vitamins
100 – (% moisture + % crude fiber + % ash + %
ether extract + % crude protein)
Concentrates

TDN
– Sum of the digestible protein, digestible
fiber, digestible nitrogen-free extract and
digestible fat x 2.25
Concentrates

Can be broken down into 2 categories:
1. Carbonaceous feeds
2. Nitrogenous feeds
• Protein & protein supplements

Function as a dietary energy supply.
– Sugars, polysaccharides, fats and oils
consisting primarily of the elements
Carbon, Hydrogen, and Oxygen
Concentrates

When feeding concentrates, the cereal grains
play the most important role.
– Provide the bulk of the energy along with a large
portion of the dietary protein.

These grains are low in fiber, and are
considered to be highly digestible by all of the
livestock species
– Nonruminants such as poultry and swine have the
bulk of their ration consisting of these highly
digestible cereal grains.
Concentrates

Cereal Grains
– Seeds from cereal plants
– Corn, Oats, Barley and Sorghum
• Primary grains fed to livestock and poultry
• Rice and Wheat are primarily consumed by humans
– Millet, emmer, spelt and triticale are fed in small
amounts.
– Grains are very palatable to livestock with the
exception of Rye.
Feed Grains Fed to Livestock and
Poultry (Million Tons)
160
140
120
100
Corn
Sorghum
Barley and Oats
Total
80
60
40
20
0
1965
1970
1975
1980
1985
Corn (Zea mays)
Most widely fed to livestock of all the
cereal grains.
 Feeding value of other grains is
compared to corn on a lb for lb basis.
 TDN around 90% for all species of
livestock
 High in starch, Low in fiber

Corn (Zea mays)
Low in protein
 Used as a feedstuff for all animals
 Approximately 25% of all corn
production is fed to hogs.
 Constitutes about 81% of all grains fed
to livestock in the U.S.

Oats (Avena sativa)





Very palatable, and considered to be an
excellent conditioning feed
High in protein when compared to the other
grains
Best balance of amino acids of the cereal
grains
TDN approximately 75%
Compared with corn, oats have a feeding
value of 70-80% on a lb for lb basis.
Oats (Avena sativa)

Oats are considered to be an excellent
feed for all livestock especially horses
and breeding stock for most species.
Barley (Hordeum vulgare)
Palatable feed
 Contains more protein, lysine and fiber
than corn
 TDN approximately 82%
 Compared to corn, barley has a 90-95%
feeding value on a lb for lb basis

Barley (Hordeum vulgare)

A large portion of the barley grown in the U.S.
is used for brewing and distilling.
 As a feedstuff:
– An excellent source of energy for Beef and Dairy
cattle
– A good source of fiber for poultry and swine.
– Barley should be ground or somehow processed
prior to feeding for all species of livestock
Sorghum (Sorghum vulgare)
Sorghum is increasing in importance as
a feedstuff, and currently ranks second
behind corn.
 Almost exclusively a feed grain in the
United States.
 Sorghum has a TDN value of 75%
 When compared to corn, sorghum has a
feeding value of 85-95%

Sorghum (Sorghum vulgare)
Approx. 98% of the sorghum grain used
in the U.S. goes into livestock and
poultry rations
 Sorghum constitutes 6-8% of cereal
grains fed to livestock
 Sorghum needs to be processed in
some way prior to feeding

Minor Cereal Grains

Millet
– TDN approximately 70%
– May be used as a feed for livestock and
poultry

Emmer
– TDN approx. 77%
– Minor grain crop similar to barley and oats.
Minor Cereal Grains

Spelt
– TDN approx 75%
– Principally used as a livestock feed.
– Grain has no milling value.

Triticale
– Hybrid of durum wheat and rye
– TDN of 84%
– Difficult to use for livestock because of high costs
Digestion

The consumption of grain in a ration results in
the acquisition of carbohydrates or more
simply put starch which the body can use for
energy for the biological processes
mentioned earlier.
 Digestion and absorption of these starches
takes place in different places in the different
types of livestock.
Digestion

Ruminants vs. Non-Ruminants
– Ruminant animals digest starches in a different
way than do non-ruminants
– In the non-ruminant starches are broken down and
absorbed in the small intestine
– This is accomplished by a series of enzymes
(amylase, trypsin, etc.) which breaks the starch
down into a 6 carbon sugar known as glucose.
• Glucose is the sugar from which the body produces ATP
(useable energy)
Digestion

In the ruminant, the starches first reach the
rumen.
 Here, the starches undergo microbial
fermentation and are converted into Volatile
Fatty Acids (VFAs)
 These VFAs are short chain carbon
molecules 2,3,4 carbon atoms long which are
absorbed into the blood stream through the
rumen wall.
Digestion

Once in the blood stream, these carbon
chains can enter the cells and directly into the
Citric Acid Cycle to be converted into ATP.
 Not all starch will be digested by the rumen.
Some will escape and enter the abomasum
(true stomach) and small intestine. Once this
occurs, digestion and absorption will occur in
the same manner as it did in the nonruminant.
Problems

The use of concentrates gives the
producer a way to boost production
levels through higher levels of energy
consumed. These grains can be used
to bolster high levels of production, or to
compensate for animals which are
unable to use forages effectively. They
are not without their problems though.
Problems

High-concentrate rations can cause
acidosis and para-keratosis of the
rumen.
– Ruminants need some roughage to
stimulate the growth of rumen papillae
– This can be accomplished by rolling or
coarse grinding the grain.
– Most feedlot finishing rations contain some
source of forage (10-15% of the ration)
Problems

Some grains need to be processed before
they can be fed
– Determined by the type of grain and the type of
animal being fed.

Grains are more expensive than most forages
on a weight basis
– When comparing the two the energy content,
digestibility and nutrient density must be
considered on a per unit of feed basis
Problems

Grains are very deficient in calcium and
certain vitamins
– Most grains contain less than .1% calcium
and adequate amounts of phosphorous
– Vitamin A is low in all grains except for
fresh yellow corn
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