Download FEED NUTRIENTS

ANIMAL SCIENCE
8647-A
FEED NUTRIENTS
INTRODUCTION
Feeding livestock is more than just giving any available feed to the animals. Young market animals require proper
nutrition to grow and finish out. Breeding animals require correct nutrition to reproduce. As humans, we need
the right balance of nutrients* supplied by the four basic food groups (meats, vegetables, dairy products, and
fruits) on a daily basis. Similarly, livestock and poultry require adequate amounts of six classes of nutrients
(proteins, carbohydrates, fats and oils, vitamins, minerals, and water) for growth, maintenance, finishing, work,
reproduction, and lactation.
The livestock or poultry producer must know the nutritional requirements of the animal species and the animal’s
function (growth, work, gestation, lactation, etc.). After determining the animal’s nutritional needs, the livestock or
poultry producer should look into the availability and cost of feeds.
All foods that sustain life contain nutrients. The animal converts the nutrients into useful forms via the digestive
system. Blood then carries the nutrients throughout the body. Nutrients pass through capillary walls and enter body
cells to provide nourishment and energy for life processes.
Nutrients are either essential or non-essential. The feed ration must supply the essential nutrients because they
cannot be produced by the body. The body can synthesize certain nutrients for growth and maintenance. Those
non-essential nutrients are manufactured in the body. A specific nutrient can be either essential or non-essential,
depending on the class of the animal.
* Underlined words are defined in the Glossary of Terms.
-1-
CLASSES OF NUTRIENTS
As previously stated, rations must supply daily feed requirements from six classes of nutrients.
Protein
Proteins are complex organic macromolecules containing carbon,
hydrogen, oxygen, nitrogen, and usually sulfur. They consist of one
or more chains of amino acids. Proteins are fundamental components of all body cells and include many substances (such as enzymes, hormones, and antibodies) necessary for proper body functions. They are essential in the animal’s ration for growth and repair
of tissue and can be obtained from feeds containing meat, fish, egg,
milk, and legume products.
Proteins consist of one or more chains of amino acids that are
required by the body. The breakdown of protein during digestion
releases the amino acids. Blood carries the amino acids to all body
parts. Single stomach animals require 22 amino acids in their body.
Those animals can manufacture 12 of the 22 amino acids but cannot store the amino acids in their bodies. As a result, they must get
a daily dose of protein containing the other 10 amino acids. Ruminants manufacture all amino acids required by their bodies. They
only need a source of nitrogen, even from a poor quality protein
source, from which the microbes in the rumen then construct the
essential amino acids.
As to their sources, proteins are of two kinds: plant protein and animal protein.
Plant proteins come directly or indirectly from plants. Examples include soybean meal, cottonseed meal, linseed
meal, and alfalfa leaf meal. Animal proteins are usually by-products of fish, dairy, and meat processing plants.
Examples are tankage, meat scraps, fish meal, and dried milk.
As to digestibility, the two classes of proteins are crude protein and digestible protein.
Crude protein is the total amount of protein (digestible and non-digestible) contained in a feedstuff. Digestible
protein is the percentage of crude protein that can be easily digested by the animal. An animal digests approximately 80% of the crude protein in a feedstuff.
Carbohydrates
Carbohydrates are organic compounds that include sugars, starches, celluloses, and gums. Carbohydrates are
produced by photosynthetic plants and contain only carbon, hydrogen, and oxygen, usually in the ratio 1:2:1. Feed
grains are high in carbohydrates and serve as a major energy source for animals. Carbohydrates are highly digestible and make up almost 75% of an animal’s ration. Excess carbohydrates produce fat in an animal.
-2-
As to digestibility, nitrogen-free extract and crude fiber are the two groups of carbohydrates.
Nitrogen-free extract consists of sugars and starches, such as those found in grains. It is highly digestible and
considered the more soluble form of carbohydrates. On the other hand, crude fiber contains carbohydrates that
cannot be easily digested by the animal. Highly fibrous plants are sources of crude fiber.
Fats and Oils
In terms of providing energy, fats and oils serve the same
function as do carbohydrates. Fats and oils are the densest forms of energy and derived from plants and animals. At room temperature, fats are solids and oils are
liquids. They both provide 2.25 times more energy than
do carbohydrates.
Animals require only small amounts of fats and oils.
However, they are very important nutrients in the ration.
Minerals
Minerals are substances necessary for the maintenance of life and good health. Some are essential components
of bodily substances, such as the calcium in bones and the iron in hemoglobin. Others help regulate the activities
of metabolism.
As to their availability and animal needs, minerals divide into two groups: macro minerals and trace (micro)
minerals.
Macro Minerals
Macro minerals include:
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
Calcium (Ca)
Phosphorus (P)
Sodium (Na)
Chlorine (Cl)
Potassium (K)
Magnesium (Mg)
Macro minerals perform certain functions in the body. They must be supplied in the feed ration, but an overabundance of any is harmful to the animal.
Calcium (Ca) and phosphorus (P) are the most abundant of the minerals in a feed ration. Calcium is necessary for
heartbeat regulation, blood clotting, muscle contractions, and bone and teeth maintenance. All biochemical reactions require calcium and phosphorus. Phosphorus is an essential constituent of protoplasm, bones, and teeth. The
calcium to phosphorus ratio (1.5 to 1) is important in feed rations.
-3-
Sodium (Na) and chlorine (Cl) are usually found together as sodium chloride (NaCl, or common salt). Salt serves
to maintain acidity levels in body fluids and proper pressure in body cells. The hydrochloric acid produced in the
stomach contains chlorine.
Potassium (K) also serves to maintain proper acid levels in body fluids and pressure in body cells. It is also
required in some enzymatic reactions in carbohydrate metabolism and protein synthesis.
Magnesium (Mg) is necessary for utilizing energy in the body and for bone growth.
Animals require larger quantities of macro minerals than they do trace minerals.
Trace Minerals
Trace minerals include:
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
Copper (Cu)
Zinc (Zn)
Manganese (Mn)
Iodine (I)
Selenium (Se)
Cobalt (Co)
Fluorine (F)
Iron (Fe)
Molybdenum (Mo)
Animals need very small amounts of trace minerals, usually ranging from 2% to 5%. However, this small percentage is essential for performing many body functions, such as:
Growth of bones, soft tissues, and teeth
Blood and body fluid processes
Vitamin utilization
Regulation of chemical processes
Reproduction
Digestion
Body tissue repair
Release of body heat for energy needs
Muscle activity
Internal organ functioning
Vitamins
Vitamins are organic compounds needed in small amounts by
the body. However, they are important for growth, maintenance, reproduction, and lactation. Vitamins do not build body
tissue as do minerals.
As to solubility and storage in the body, vitamins are either
fat-soluble or water-soluble. They are obtained naturally from
plant and animal feedstuffs.
The body stores fat-soluble vitamins. Large amounts of fatsoluble vitamins can be deadly to an animal.
-4-
This is not true for water-soluble vitamins, which cannot be stored in the body. Regular intake of adequate amounts
of water-soluble vitamins is important.
Fat-soluble vitamins include:
ƒ
ƒ
ƒ
ƒ
VitaminA
Vitamin D
Vitamin E
Vitamin K
Water-soluble vitamins include:
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
Thiamine (Vitamin B1)
Riboflavin (Vitamin B2 or Vitamin G)
Pyridoxine (Vitamin B6)
Vitamin B12
Folic Acid (Vitamin Bc)
Biotin (Vitamin H)
Choline
Inositol
Niacin or Nicotinic Acid
Pantothenic Acid
Water
All animals require water for body functions. Water is
necessary for digestion and absorption of nutrients,
removal of waste, production of milk, shaping of cells,
and regulation of body temperature. Water is a vital
factor in nutrition.
Water is the largest component of bodies and constitutes approximately 50% of body mass. The animal’s
feeding habits directly affect the amount of water consumed. Animals require approximately three pounds
(approximately 1/3 gallon) of clean water for each
pound of solid feed eaten.
SUMMARY
Similar to people, animals need adequate nutrition for their bodies to function properly. A livestock or poultry
producer must know what nutrients are required in an animal’s diet and provide them in the correct amounts
corresponding to the animal’s purpose in the livestock program.
-5-
Acknowledgements
Kristy Corley, Graduate Technician, Department of Agricultural Education,
Texas A&M University, revised this topic.
Larry Ermis, Curriculum Specialist, Instructional Materials Service,
Texas A&M University, reviewed this topic.
Vickie Marriott, Office Software Associate, Instructional Materials Service,
Texas A&M University, prepared the layout and design for this topic.
Christine Stetter, Artist, Instructional Materials Service,
Texas A&M University, prepared the illustrations for this topic.
REFERENCES
Baker, J. K. et al. Animal Health. Danville, IL: Interstate Printers & Publishers, Inc., 2000.
Ensminger, M. E. Animal Science. Danville, IL: Interstate Printers & Publishers, Inc., 1991.
Gillespie, James R. Animal Nutrition and Feeding. Albany, NY: Delmar Thomson Learning, 1987.
Livestock Extension Publications. [On-line]. Available: http://texaserc.tamu.edu/catalog/
topics/Livestock.html. [2002, March].
Nutrients for Cattle. [On-line]. Available: http://www.agric.gov.ab.ca/agdex/400/00053003.html [2002, March].
Poultry Extension Publications. [On-line]. Available: http://texaserc.tamu.edu/catalog/topics/
Poultry.html. [2002, March].
GLOSSARY OF TERMS
Capillary – Relating to any of the small blood vessels connecting arterioles with venules.
Metabolism – The chemical processes occurring within a living cell or organism that are necessary for the
maintenance of life.
Nutrients – An essential or non-essential element or compound in a food or feed.
Organic – Relating to carbon compounds of animal or vegetable origin.
Ruminants – Hoofed and even-toed mammals with a four-compartment stomach.
Soluble – Capable of being easily dissolved, such as soluble fats.
Synthesize – To create a whole or complete unit from parts or components.
Tankage – Protein supplement used for feeding livestock and which contains ground meat and bone by-products of slaughtered animals.
Trace – An extremely small amount.
-6-
SELECTED STUDENT ACTIVITIES
SHORT ANSWER/LISTING: Answer the following questions or statements in the space provided or on additional paper.
1.
List the six classes of nutrients.
a.
_______________________________
d.
_______________________________
b.
_______________________________
e.
_______________________________
c.
_______________________________
f.
_______________________________
2.
The feed ration must supply the ____________________ ____________________ because they cannot be produced by the body.
3.
Distinguish between crude protein and digestible protein.
____________________________________________________________________________
____________________________________________________________________________
____________________________________________________________________________
4.
In regard to feed requirements, what is the main difference between macro and trace minerals?
____________________________________________________________________________
____________________________________________________________________________
FILL IN THE BLANK: Complete each statement with the correct word or phrase.
5.
____________________ is a necessary nutrient in largest supply in the animal’s body.
6.
List the four fat-soluble vitamins.
a.
_______________________________
c.
_______________________________
b.
d.
_______________________________
7.
_______________________________
List four body functions that require adequate amounts of trace minerals.
a. _________________________________________________________________________
b.
_________________________________________________________________________
c.
_________________________________________________________________________
d.
_________________________________________________________________________
-7-
8.
WORD FIND: Circle the words hidden in the puzzle below. The words may run horizontally, vertically,
diagonally, forwards, or backwards.
CALCIUM
CARBOHYDRATES
CHLORINE
CRUDE FIBER
FATS
I
P
F
L
M
S
S
O
R
S
I
Y
F
I
K
U
M
A
S
C
M
N
I
V
A
L
F
O
B
I
R
E
N
A
T
R
A
U
E
U
R
U
R
E
T
A
I
V
S
T
A
I
T
I
T
N
T
I
D
N
I
F
N
C
E
T
W
E
A
T
C
K
S
F
A
S
W
F
E
V
FEEDSTUFF
FISH MEAL
IRON
MINERALS
NUTRIENT
F
A
A
A
E
M
C
F
T
O
I
T
R
A
B
C
A
U
N
I
N
G
R
R
A
R
A
N
S
N
D
T
E
N
O
R
I
D
S
I
S
I
E
T
C
E
S
U
R
E
N
I
R
O
L
H
C
D
I
N
A
F
I
S
H
L
M
E
A
L
T
S
L
R
U
N
N
N
M
F
O
F
E
S
M
L
A
M
S
I
E
S
T
A
S
O
U
U
S
P
R
A
M
F
A
A
I
U
S
T
T
I
A
T
I
R
I
T
N
R
I
A
I
M
S
N
N
F
T
I
I
O
R
M
I
D
S
K
U
O
H
M
I
L
E
R
G
G
M
E
C
E
I
W
O
E
E
N
L
T
OILS
POTASSIUM
PROTEIN
RIBOFLAVIN
RUMINANT
N
L
S
R
H
A
T
N
A
A
B
F
R
S
I
C
T
R
O
E
E
A
A
F
E
N
I
E
L
I
F
R
A
S
A
M
A
T
M
I
A
L
A
N
C
M
T
A
F
U
I
N
E
L
I
W
R
N
S
N
S
A
T
T
A
H
A
O
T
S
I
G
C
R
N
N
D
T
R
E
I
A
R
T
C
B
E
S
C
I
A
I
K
M
S
P
Y
I
I
I
L
O
I
S
T
D
D
I
O
K
U
D
L
E
A
O
H
R
S
N
I
V
F
L
U
E
T
C
N
M
N
M
A
E
I
T
O
M
T
G
R
N
Y
R
E
A
R
A
E
E
T
F
D
L
E
A
B
T
O
S
L
O
C
F
D
V
T
R
U
R
W
I
E
T
E
S
R
T
I
B
SODIUM
TANKAGE
TRACE
VITAMIN
WATER
I
N
I
I
E
R
N
R
E
A
I
A
L
O
O
S
A
R
L
C
T
D
I
R
U
M
I
N
A
N
T
S
T
N
E
I
C
U
S
B
S
I
N
U
T
R
I
E
N
T
A
E
D
E
A
U
A
E
R
T
A
N
O
O
M
M
L
R
R
R
I
A
S
B
R
M
S
R
A
O
D
N
T
A
E
A
A
G
N
T
A
O
A
M
T
F
U
L
D
F
ADVANCED ACTIVITIES
1.
Select an animal (hog, cow, horse, chicken, etc.) and research the feed nutrients required in that animal’s daily
ration for each of the applicable functions: growth, maintenance, finishing, work, reproduction, and lactation.
2.
If animals are not fed properly, their needs for vitamins and minerals may not be met. Research vitamin and/
or mineral deficiencies in animals and report findings to the class.
ALL RIGHTS RESERVED
Reproduction prohibited without written permission.
Instructional Materials Service
Texas A&M University
2588 TAMUS
College Station, Texas 77843-2588
http://www-ims.tamu.edu
2002
-8-