session 2 basic nutrients

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“a substance that must be consumed as part of the diet to provide a source of energy, material for growth, or substances to regulate growth or energy production.”

- Bantam Medical Dictionary

“a raw or processed agricultural commodity or other nutrient source”

- SACN, 5- SACN, 5thth Ed. Ed.

Essential “Non-dispensable”Body cannot produce

Non-Essential “Dispensable”

The body can produce

Conditionally EssentialRequired during certain physiologic

or pathologic conditions

Supply energyCofactors in metabolic chemical reactions

Transport substances throughout bodyRegulate body temperatureImpact food palatabilityForm structural components of the body

WaterWater CarbohydratesCarbohydrates ProteinProtein FatFat MineralsMinerals VitaminsVitamins Antioxidants*

EnergyProducingNutrients

Most important nutrientBody composition ~ 70% of fat-free body

weightFunctions:

Solvent Transports materials Chemical reactant (hydrolysis) Supports blood volume and pressure Regulates body temperature Provides shape to body

How Water Gets Into an AnimalHow Water Gets Into an AnimalMetabolizableMetabolizable IngestedIngested

Breakdown of Breakdown of carbohydrates, protein, carbohydrates, protein, fat as used for energyfat as used for energy

Free WaterFree Water

Routes of Water LossRoutes of Water Loss

Urine, Feces, Respiration, Perspiration, Milk, Urine, Feces, Respiration, Perspiration, Milk,

* Loss of 15% results in death

Water Content Varies by Water Content Varies by NutrientNutrient

CarbohydrateCarbohydratess

0.6 grams of water per gram 0.6 grams of water per gram of carbohydrateof carbohydrate

ProteinProtein 0.4 grams of water per gram 0.4 grams of water per gram of proteinof protein

FatFat 0.2 grams of water per gram 0.2 grams of water per gram of fatof fat

What types of things influence the amount

of water an animal

needs?

Species

Environment (climate, air movement, etc.)

Food type and source

Diet composition (high protein, fiber, mineral salts)

Life stage and lifestyle

Water quality

Total Dissolved Solids- Index for measuring water quality- More dissolved solids, decreased water

quality- 6 most common minerals present in water are

chloride, sodium, calcium, magnesium, sulfates and bicarbonate

- Other factors: pesticides, pathogens, bacteria, algae, protozoa

- < 2,500 mg/L dissolved solids desired

Energy: “the ability to do work” -SACN, p.26

Calorie: amount of heat required to raise the temperature of 1 gram of water 1°C.

Kilocalorie = 1000 calories

All living cells require energy

After water, energy is most critical requirement in nutrition

Carbohydrates, Protein, Fat provide energy from the diet

Not all of consumed energy is used

GROSSENERGY(GE)

DIGESTIBLEENERGY(DE)

METABOLIZABLEENERGY(ME)

Gross Energy (GE)

Total amount of heat produced when feed is burnt completely

GE determines total energy content of a feed, but doesn’t equal amount of energy available to the animal

GROSSENERGY(GE)

Digestible Energy (DE)

the energy remaining after the energy lost in feces is subtracted from the gross energy

Measure of the energy absorbed from the feed after consumption

Not a true measure, some energy is from tissue sloughing from the GI tract

DIGESTIBLEENERGY(DE)

Digestible Energy

DIGESTIBLE ENERGY = Gross Energy – Fecal energy losses

Image source: Dr. Geneva Acor, Hill’s Pet Nutrition, Inc.

Metabolizable Energy (ME)

Energy available to the animal after energy from feces, urine, and gases has been subtracted from the gross energy

More accurate than DE for estimating amount of energy available to animal

Expensive: feeding trials

METABOLIZABLEENERGY(ME)

Metabolizable Energy

METABOLIZABLE ENERGYMETABOLIZABLE ENERGY = Gross Energy – Fecal, Urine, Gas = Gross Energy – Fecal, Urine, Gas losseslosses

GrossEnergy

Digestible Energy

Image source: Dr. Geneva Acor, Hill’s Pet Nutrition, Inc.

Most accurately predicts amount of energy available to the animal

Has been determined on a few feedstuffsUsed widely in formulating diets for ruminant

species

Method for estimating energy content in a feed

Food is fed and all dietary components are measured

Amount of dietary components in feces is measured

Digestible crude protein+ digestible crude fiber+ digestible nitrogen free extract ( starches

and sugars)+ 2.25 X Digestible ether extract ( fat)TOTAL DIGESTIBLE NUTRIENTS

WHAT CHARACTERISTI

CS OF A FEED MIGHT AFFECT

ITS DIGESTIBILITY?

Maturity of plant material- as plants mature, an undigestible material called lignin increases in plant cell walls

Energy producing nutrient

Composed of carbon (C), hydrogen (H), oxygen (O) – CH2O

Includes sugars, glycogen, starch and cellulose

Mainly in plants (~75% of solid plant material)

Cell layer is cellulose; Starch is the energy source

Monosaccharides CH2O GLUCOSE

Glucose & fructose most common

Glucose is immediate source of energy for cellular reactions i.e. tissue repair, muscle contractions, nerve transmissions

Body continually supplies glucose to blood from stored compounds in liver (glycogen)

Extremely Important

Disaccharides (CH2O)2

Short chain of 2 CHO molecules

Lactose (milk sugar); Sucrose (table sugar)

Plants convert their stores of carbohydrates to sucrose for easy transport through the plant

Proteins often have attached disaccharides

Polysaccharides (CH2O)3

Includes starches, glycogen and celluloseThe most abundant of all carbohydrates

Starches- from plants, broken down into glucose subunits

Glycogen- storage form of glucose in animal cells, stored in liver and muscle, broken down to release glucose

Cellulose- comprises majority of plant cell wall, insoluble, digested by bacteria in the herbivore digestive tract

Energy producing nutrient

Found in highest concentration of any nutrient except water in all living organisms

Composed of carbon (C), hydrogen (H), oxygen (O), and nitrogen (N) (and sometimes sulfur (S) and phosphorus (P)

WHAT FUNCTIONS DO PROTEINS PERFORM

IN THE BODY?

Functions

Tissue BuildingHormonesGrowthEnzymesImmune SystemBlood cells

Made up of amino acid (AA) sub-units

Definition:Small organic compound that consists of an amino group (NH2) on one end and a carboxyl group (COOH) on other plus a special group that defines the individual amino acid

AA are linked together by peptide bonds

2 linked bonds = dipeptide

3+ linked bonds = polypeptide

Synthesized by plants, rumen microorganisms

Non-herbivores get AA in diet

Absorbed in the anterior small intestine

Most protein in plants and animals composed of only 20 amino acids

10 Essential Amino Acids (11 for cats)

Essential Amino AcidsEssential Amino Acids

Phenylalanine Histidine

Valine Arginine

Tryptophan Lysine

Threonine Leucine

Isoleucine

Methionine Taurine*Cats only

Requirement for monogastric and avian species is for amino acids

High needs for: young, rapidly growing gestating and lactating animals surgery or trauma certain pathologic conditions

Protein DeficiencyPoor growth rate in young; weight loss in

adultsExcess sheddingHigh neonate mortality; reduced egg

production, infertilityCauses of Protein DeficiencyCauses of Protein Deficiency

Inadequate food intakeInadequate food intake Poor quality proteinPoor quality protein Maldigestion or malabsorptionMaldigestion or malabsorption Protein losing enteropathy, NephropathyProtein losing enteropathy, Nephropathy Common in catteries and kennels Common in catteries and kennels

Uncommon due to cost of feedUsed for energy or stored as fatChronic excess stresses kidneysExcretion of urea increases nitrogenous

wastes that build up in bloodstreamWhen urea or other non-protein sources are

fed to ruminants, toxicity and death occur if diet has insufficient carbohydrates

Energy producing nutrient

Insoluble in water

Include fat, oils, complex sterols

Comprised of carbon (C), hydrogen (H) and oxygen (O)

Fat is solid at room temperature

Oil is liquid at room temperature

Functions

InsulationAbsorption of fat-soluble vitamins Hormone synthesisStructure to cell membraneMoisture to skinPalatability

Accounts for most of body’s stored energy“Fat reserves”

Fat provides twice as much energy as CHO and protein

Source of essential fatty acids Hydrophilic, absorbs water and takes up

more space in the body

Definition:A chemical unit that occurs naturally, either singly or

combined, and consists of strongly linked carbon and hydrogen atoms in a chain-like structure

Important for lipid-protein structure of cell membrane

Linoleic acid and Linolenic acid are essential for mammalian species. (Both are Omega 6 fatty acids)

Arachadonic acid is required in cats

Important to brain developmentIam’s - “How to Grow Smart Puppies”™

Beneficial in inflammatory conditions

Common sources found in feeds:Flaxseed, linseed, menhaden fish, animal fat,

evening primrose oil, black currant oil

Signs of EFA DeficiencySigns of deficiency: scaly skin, necrosis of tail,

reduced reproduction, edema, hemorrhaging, poor feathering in chickens

- Seen in pigs, chickens, calves, dogs, mice and guinea pigs

- Rare in ruminants, despite a fat-free diet, because the microbes produce adequate amounts of EFA

1. Neutral fats2. Phospholipids3. Sterols4. Carotenoids5. waxes

Most abundant fat in living thingsIncludes saturated fats and unsaturated fatsSaturated-have no shared carbon bondsUnsaturated- one shared bond between

carbonsPolyunsaturated-two or more shared bonds

between carbons

Form cell membranes- one hydrophilic end and one hydrophobic end

Fatty acid portion ( tail) is hydrophobic and not water soluble

Lipids that have no fatty acidsOccur in cell membranesInclude sex hormone ( estrogen, testosterone)Cholesterol, bile salts and sterols,

( biologically important)1.cholesterol- most common sterol in animal

cell tissues2.Bile salts- role in fat digestion in small

intestine

Red and yellow pigment cells of all plantsClassified as lipids because of insolubility in

water and oily consistencyVitamin A comes from splitting pigment

Long chain fatty acids tightly packed Firm consistency: repel waterHelp form the cuticle on plants and leavesKeeps feathers of water fowl clean and dry

Monogastrics1.Primary site is small intestine2.Bile and pancreatic lipase3.If large amount of fat is mobilized for energy,

ketones form and excessive amounts are dumped into urine, milk and lungs

Ruminants- microbes convert unsaturated fats to saturated fats

Small, organic compounds required by body for normal function

Cofactors in ezymatic reactions

Classified as fat solublefat soluble or water solublewater soluble - Absorbed through variety of ways

Important in milk – especially colostrumcolostrum

Different for each vitamin

Vision Blood clotting factors Immune defense Epithelial tissue Bone mineralization and

resorption Neural transmission

Vitamin AVitamin CPotassium

ZincVitamin E

IronMagnesium

CalciumVitamin KSelenium

Vegetable OilTuna, red meat

Citrus, green peppersCarrots, pumpkinBeef, Brazil nutsSardines, milkYogurt, lentils

SoybeansNuts, bananas

Cauliflower, broccoli

Vitamins A, D, E, K Higher potential for toxicity than water

soluble vitamins

Require fat and bile salts to be absorbed

Important part of visual proteins

Key for epithelial tissues (skin, lining of body cavities)

Beneficial to immune system

Signs of deficiency: poor coat, retarded growth, anorexia

Signs of toxicity: anorexia, “Cervical spondylosis” in

cats

Calcium/Phosphorus balanceKey in bone resorption and mineralizationAbsorbed as ergosterol, converted to

calciferol (D2) in skin

Kidneys convert D2 to different compound used for calcium absorption

Signs of deficiency: Rickets, posterior paralysis

Signs of excess: anorexia, kidney stone, FORLs

Antioxidant “Tocopherol”Alpha tocopherol: active in bodyMixed tocopherol: active in food

Protects cell membranes

Signs of deficiency: sterility in males, steatitis in cats, immunodeficiency

Signs of toxicity: Increased clotting time

Vital to blood clotting proteins

Synthesized by microbes in ruminant gut

Deficiency is rare in all species except poultry

Signs of deficiency: increased clotting time, hemorrhaging

Sign of excess: minimally toxic

B-Vitamins, Vitamin C

Minimally toxic, due to excretion from the body in urine

Key as cofactors in enzymatic reactions

Thiamin (BThiamin (B11)) Pyroxidine (BPyroxidine (B66))

Riboflavin (BRiboflavin (B22)) Biotin (BBiotin (B77))

Niacin (BNiacin (B33)) Folic Acid (BFolic Acid (B99))

Pantothenic acid Pantothenic acid (B(B55))

Cobalamin (BCobalamin (B1212))

Functions varied among forms of Vitamin B

No single food source has enough vitamin B - must be gained from multiple sources

Riboflavin deficiency is rare

Niacin deficiency results in pellagra with dermatitis; dementia

Antioxidant

Collagen synthesis

Important in Carnitine synthesis

Signs of deficiency: scurvy Signs of toxicity: rare

Natural component of animal cells

Most carnitine (~98%) in body lives in skeletal and cardiac muscle

Helps transport fatty acids into cells

Helps build lean tissue

In nutrition, mineral means all inorganic elements in a food

Major portion of body fluids (electrolytes)

Important in enzymatic reactions

“Ash”

Macro MineralsMacro Minerals

CalciumCalcium

PhosphorusPhosphorus

SodiumSodium

MagnesiumMagnesium

PotassiumPotassium

ChlorideChloride

SulfurSulfur

Micro MineralsMicro Minerals

ChromiumChromium

CobaltCobalt

CopperCopper

FluorineFluorine

IronIron

IodineIodine

ManganesManganesee

MolybdenuMolybdenumm

NickelNickel

SeleniumSelenium

SiliconSilicon

ZincZinc

Largest amounts found in skeletal system

Provide structural rigidity

Some functions:Iron is essential part of hemoglobinIodine is component of thyroid

hormoneSodium is key to body’s pH level

Of total minerals in animal’s body…Ca = 46% and P = 29%

Absorbed from the GI tract

Fat sometimes chelates certain minerals, thereby reducing their availability to animal

Young are more efficient than old at absorbing minerals

Requirements vary by species

Definition:

“an especially reactive atom or group of atoms that has one or more unpaired electrons; produced in the body by natural biological processes or introduced from an outside source (as tobacco smoke, toxins, or pollutants) and that can damage cells, proteins, and DNA by altering their chemical structure.”

- Merriam-Webster Dictionary

DNA

Mitochondria

Attack cell membranes,Attack cell membranes,DNA & MitochondriaDNA & Mitochondria mutations in DNAmutations in DNA changes fluidity of changes fluidity of

cell membrane cell membrane

Cause Cause oxidative stressoxidative stress in the bodyin the body

Creates DNA damageDamage accumulates over course of animal’s lifeInjures cellsResponsible for lots of chronic illnesses

Cancer, Kidney disease, Cardiovascular disease, Cognitive Dysfunction Syndrome, etc

PollutionRadiation

MetabolismChemicals

Food Additives

Mitochondria“Powerhouseof the Cell”

DamagedMitochondria

Body’s Defense

sBody’s Defense

s

Body’s Defense

s

Body’s Defense

sXX

XX

Definition:

“a substance that inhibits oxidation or reactions promoted by … free radicals”

-Merriam-Webster Dictionary

Inactivate free radicals

Improve cellular efficiency

Work best in conjunction with other antioxidants

(help to regenerate each other)

Some are active in food; some are active in the body

Fights oxidation in the food

Carotenoids & Flavonoids (from Vitamin A)

Mixed Tocopherols (form of Vitamin E)Vitamin CEthoxyquin

Commonly marketedCommonly marketedin dog and cat foodin dog and cat food

Fight oxidation in the animal’s cells

Alpha tocopherols (form of Vitamin E)Ascorbic AcidSeleniumLipoic AcidBeta CaroteneCarotenoidsFlavanoids

“Cowboy”

SMALL ANIMAL NUTRITION: ENERGY CALCULATIONS &

LIFE STAGE/LIFE STYLE NUTRITION

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