Download Lecture Materials/Unit 1

FEEDS & RATION FORMULATION
Spring 2017
INTRODUCTION

Feeds represent the most expensive input cost for the
livestock producer

Expensive to maintain the animal

Expensive if don't supply nutrient in adequate amounts to get good
performance

Expensive if overfeed nutrients relative to the animal's requirements
INTRODUCTION

Basic nutrients

Water

Protein

Energy: fat and carbohydrates

Minerals: macro and micro

Vitamins: fat soluble and water soluble
INTRODUCTION

Important to understand most limiting nutrient
concept:

Animal performance

Environment

Balance

Cost
Feeds and ration formulation involves applications of the
process of nutrient utilization:




Ingestion
 prehension of feed, chewing and swallowing to the initial digestive
organs
Digestion
 reduction of food to utilizable form; physical and chemical processing of
ingested food
Absorption
 food is reduced to utilizable form; transported from inside the digestive
tract to the blood stream
 active transport
 passive diffusion
Metabolism
Biological Functions that Require Nutrients
Maintenance: "the maintaining of an animal in a state of well
being or good health from day to day".
A maintenance ration is the feed required to adequately
support an animal doing no non-vital work, making no growth,
developing no fetus, storing no fat or yielding no product.
As much as 100% of an animal’s ration
Maintenance

Energy for vital functions: heart, respiratory,
membrane transport


energy expenditure gives off heat
Maintain body temperature

sources: heat from work of vital organs, heat from
nutrient utilization, heat from work of normal activity,
heat from economic work, heat from work of shivering
Maintenance

Protein for repair of tissue

there is constant breakdown or turnover of body tissue protein
 excreted largely as urine
 N excreted as urine during starvation equals maintenance
requirement for protein

Minerals: some minerals excreted daily (not a problem)

Vitamins

Others: water, small amount of fats
Growth: increase in muscle, bone, and connective tissue
(accumulation of fat is not growth)

Protein -- dry matter of muscle and connective tissue

Energy

Minerals -- especially calcium and phosphorus in young

Vitamins

Water -- free muscle tissue is about 75-80% water
Fattening

Deposition of unused energy in the form of fat



Internal fat (around abdominal organs), intermuscular, subcutaneous
Intramuscular fat
Fattening versus growth: growth is easier to deposit




muscle is mostly water
fat may actually replace water
2.25 x's amount of energy in fat versus protein or carbohydrate
nature of the growth curve for all animals
Changes in body composition with
increased age and weight of pigs
age (days) 1
weight (kg) 1-2
17
2-2
28
7
89
25
age (days)
weight (kg)
144
60
183
90
200
110
water
protein
fat
ash
Normal postnatal growth curves
Figure 1. Normal postnatal growth curves of
ofmuscle,
bone, and
muscle,
bone,
fat. and fat.
Total
Maturity
Muscle
Fat
Mass
Birth
Bone
Time
Reproductive animals

Milk production:



Fetal development




nutrient requirements are in proportion to amount of milk produced
Major nutrients required are: energy, protein, Ca and P
***fetal requirement for nutrients is not great
83 lb calf (25% DM) = 22 lb of DM; which is only about 4 days of milk
for the lactating animal
importance of nutrition during late gestation may be preparation for
lactation (and rebreeding in cattle)
Others = wool, work, others
Nutrients from a Feed Management Perspective
(Chapter 3, Kellems and Church)

Water

Water - most crucial nutrient -- most immediately required

70% of lean body mass

Can only lose 10% of body water

Consume 3-4 times amount of water as dry matter (DM)

Consume an amount of water which is needed to maintain homeostasis
(GIT, blood)
Water

Functions
transport (digesta, blood)
 urine -- media to excrete nitrogenous waste
 evaporative cooling
 rumen microbes


Sources
drinking water
 feed -- some feeds have up to 85% water
 metabolic water -- oxidation of nutrients to produce
water

Water

Practical Applications

water consumption is critical to maintain DM (nutrient)
intake

requires management during hot and cold weather

requires management when high salt diets are fed
Energy

Energy is very difficult to measure quantitatively


defined as calories -- amount of energy required to
raise 1 g of water 1o C -- kilocalorie – megacalorie
Carbohydrate:
C6H12O6 + 6 O2
C:H:O 1:2:1
6 CO2 + 6 H2O
Energy
Energy - Carbohydrates

Monosaccharides:







Glucose -- primary sugar
Fructose -- ketose, sweet, corn sweeteners
Galactose
Mannose
Arabinose
Xylose
Ribose
Energy – Carbohydrates - Polysaccharides

Nonstructural carbohydrate (NSC) or non-fiber carbohydrate
(NFC): mostly starch (some simple sugars), very extensively
digested and/or fermented (90+ percent), not bulky

Amylose

Amylopectin: waxy grains, probably more extensively fermented
ruminally

Glycogen; animal energy storage; liver and skeletal muscle
Amylose -1, 4 linkage
CH2OH
CH2OH
OH
OH H
H
H
OH H O OH H OH
H OH
O
O
O
O
O
O
O
O
O
O
H OH
O
CH2OH
OH H
H H
HO OH H O
H OH
O
O
Structure of starch: Amylopectin,
showing 1:6 branch point
6
CH2OH
4
1
O
6
CH2OH
O
4
1
6
CH2
O
1
4
6
CH2OH
O
4
1
O
O
Energy – Carbohydrates - Polysaccharides

Structural carbohydrate = fiber: less digestible even in the ruminant, very
bulky - occupies much space in the GIT

cellulose: primary carbohydrate in fiber, comprised solely of β-1,4 linked
glucose, lowly digestible

hemicellulose; secondary carbohydrate in fiber; made up of glucose,
xylose, arabinose, mannose, galactose

lignin -- most significant anti-nutritional factor
• amorphous polyphenols
• gives support to the cell wall structure
• present in the "woody" plant parts
• increase as plant matures
Energy – Carbohydrates – Other Polymers

Pectin -- plant cell wall cement

Cutin - waxy coat of leaf surface
Diagram of a plant cell showing cell wall structure
Cell Content
Protein
Sugar
Fats
Starch
Pectins
Primary
Wall
Secondary
Wall
Hemicellulose
Cell
Wall
Lignin
Cellulose
NDF
ADF
Energy – Structural Carbohydrates

Chemical treatment - objective is to make the SC fraction of
forage more digestible

Ammoniation: anhydrous, aqua or urea
•
Untreated straw  42% digestible
Ammoniated straw  55% digestible
•
Effectiveness depends on conditions during treatment
•

Alkaline hydrogen peroxide; oxidizes the lignin
Ruminant system of carbohydrate digestion and
absorption:
Polysaccharide
simple sugar
absorbed 6 ME
or
Polysaccharide simple sugar fermented to VFA
absorbed
ME
Ruminant system of carbohydrate digestion and
absorption:
Ruminant system of carbohydrate digestion and
absorption:

Propionic acid, most energy efficient VFA

Propionic acid increased by:



Feeding higher level of grain
Feeding ionophores
Ionophores (Rumensin and Bovatec):

Acetic acid,  propionic acid, no change in total VFA
Feed:gain

Methane production,  bloat

Ruminant system of carbohydrate digestion and
absorption: Effect of feeding grain
Ruminant system of carbohydrate digestion and
absorption: Effect of feeding grain
Energy – Lipids

fat = glycerol + fatty acids


triglyceride = glycerol + 3 fatty acids
Common fatty acid length -- C14 to C20

very hydrogenated – energy

saturated vs. unsaturated

essential fats



linoleic: C18-2
linolenic: C18-3
arachidonic: C20-4
Energy – Lipids

Feed applications

fats contain 2.25 x's energy per weight as CHO's -- CHO = 4 kcal/g;
fat = 9 kcal/g

increase the energy density of a ration; must be limited, usually 5-6% of
ration as lipid for ruminant, 6-7% for monogastric

reduce dustiness
may increase palatability
aid absorption of vitamin A,D,E,K
may decrease absorption of Ca, Mg, Na



Energy – Lipids

Feed applications – continue

fat will reduce fiber digestion in the rumen; commonly seen in the
lactating dairy cow; restrict fat to about 6 percent of the total diet DM

now have ruminally inert fats on the market to avoid lower fiber
digestion; best to have a combination of fat from basal ingredients, an
oil source such as whole cottonseed or full fat canola, and inert fat

fat metabolism -- ketones -- ketosis
Protein

Most expensive nutrient per weight to supply

Functions






Muscle
Enzymes
Hormones
Antibiotics
skin, hair
Amino acids are what is actually required by the animal -building blocks of protein
Protein

Protein  digestion  free AA  absorption  transported to the cell to
synthesize a new protein for use by the animal

Animal can not absorb an intact protein

21 naturally occurring AA

10 essential AA
Protein



Dietary Essential AA -- an amino acid required by an animal and can not be synthesized
by the animal in the amounts needed; and therefore must be present and available in the
diet
 Arginine
 Histidine
 Isoleucine
 Leucine
 Lysine
 Methionine – S-containing, Cystine may provide ½ the reqmt
 Phenylalanine -- tyrosine may provide ½ of the requirement
 Threonine
 Tryptophan
 Valine
Nonessential AA -- required by the animal but can be produced in adequate amounts
Limiting AA -- AA that is first depleted during protein synthesis
Ruminant system of protein digestion and absorption

** dietary AA are not the same AA that are absorbed and used to
synthesize animal protein
Summary -- Advantages of the ruminant
system
º
utilize fibrous feeds
º
utilize NPN
º
B vitamin production (plus vitamin K)
Minerals
Macro mineral (Ca, P, K, Na, Cl, S, Mg)
Micro mineral ( Fe, Co, Cu, F, I, Mn, Mo, Se, Zn, …)



sulfates more bio-available than oxides
chelated (or proteonated) minerals (Zn, Mn, Cu, Fe, Se) may be beneficial, but
are much more expensive
 Most recent is FDA approval of Se-methionine
Cu, Se, Zn and Fe are now recognized to be important factors in immune
function
Ca, P and Mg needed in greatest abundance and most commonly
supplemented
Minerals

Antagonists-an
element which
inhibits the
absorption or
transport of
another element
Minerals
A.
Sources
Ca%
P%
1.
2
3.
4.
5.
6.
Oyster shell
Ground limestone
Defluorinated rock phosphate
Dicalcium phosphate
Mono-ammonium phosphate
Mono-sodium phosphate
38
36
33
23.4
7.
8.
Forages
Grain
0.3-2
<0.05
0.15-0.4
0.3-0.4
9.
Requirement
0.3 to 0.4
0.25
18
18.7
26.9 (12.2% N)
22.4
Ca:P ratio = 1.2 to 1.5:1 for growing animals and dairy
6:1 laying hens
Minerals

Phytate phosphorus

Form of P bound in phytic acid, most P in grains is in phytate form

This form of P is lowly available for monogastrics but is available for
ruminants

Interest in phytase to increase utilization of P in basal ingredients - both
endogenous and exogenous phytase
Minerals

Magnesium -- hypomagnesemia -- grass tetany

during cool season, low root uptake of Mg
or if dietary Ca is too high
or when high soil (forage) K
or low soil P
desire K:(Mg + Ca) < 2.3 in grazed forage

supplement with MgO, MgSO4, legumes





Symptoms include muscular twitching, collapse, convulsion
Trace minerals
Selenium

Selenium -- Se deficient soils
 FDA will now allow
supplemental Se at .3 ppm;
seems to be level we need
for of Se-deficient soils
Copper

Copper - - deficiency of grazing
animals throughout the western
states; probably more associated
with Mo antagonism

Want a Cu:Mo ratio in
vegetation greater than 7
Thiomolybdates
Mo, S (as sulfate, sulfide or S amino acids), Cu and Fe all enter the rumen via feed, soil, water or supplements. Reactions
occur between Mo and S enabling the formation of thiomolybdate compounds which will readily bind Cu. In the absence
of rumen-available Cu (rumen-labile Cu), thiomolybdates are able to be absorbed through the rumen wall and small
intestine, allowing them to bind to Cu-containing substances, including enzymes whose activity will be reduced, thus
causing clinical problems often quoted as Cu deficiency, even though it is strictly a thiomolybdate toxicity.
Gould and Kendall, 2011
Copper Toxicosis

Sheep particularly sensitive to copper
5
ppm Cu
 Excessive Cu builds up in RBC, causing Heinz-body
formation and methemoglobin production
 Can’t bind oxygen- chocolate blood
 Release of hemoglobin damages kidneys

Avoid feeding cattle mineral
Vitamin premixes

Fat (A, D, E, K) vs. water soluble (B vitamins, C)

Vitamin Premixes (0.5-1.0% of diet)
 Complete
vitamin packages-may contain synthetic
antioxidants to increase stability
 Loss of vitamins in feedstuffs
 Heat/humidity
increase oxidation of A, E, thiamin, riboflavin
and biotin
 Vitamin/mineral premixes less stable
Vitamin supplementation

Monogastric animals
 Corn-soy
diet generally adequate in E, thiamin, B6, and
biotin
 Pigs and poultry -supplement Vit A, D, E, K, niacin,
riboflavin, pantothenic acid, B12
Horses

Horses can meet B vitamin needs due to large production in LI
(despite poor absorption)
Vitamin supplementation

Ruminants
 Vitamins
C, D synthesized, and rumen bacteria make B
vitamins and K
 Generally supplement Vitamin A, sometimes D
 recognize
that young animals and ruminants without
green forage (or fed stored forage) may respond
to vitamin E supplementation; involved in immunity;
injection or feed
 Concentration
of fat soluble vitamins in colostrum is
greater than in milk