Feedstuff Analysis

Chris Ellason

Feedstuff Analysis

Feed Sampling Proximate Analysis

– Dry matter– Ash– Crude Protein– Ether Extract– Crude Fiber– NFE

Detergent Method

NDF - cell wall components– cellulose– hemicellulose– lignin– silica– heat damaged protein

Detergent Method

ADF - Acid Detergent Fiber– lignocellulose

NDF used to predict gut fill and intake ADF used to predict digestibility ADIN - acid detergent insoluble nitrogen

Know the Form of the Numbers

Dry Matter Basis As-fed Basis Air-dry Basis

Energy Measurements

Gross Energy - GE – total potential energy of a feedstuff– determined by bomb calorimeter

Fecal Energy - FE– Energy from undigested feed and other

components of feces– Determined by bomb calorimeter

Energy Measurements

Digestible Energy - DE– GE - FE

Gaseous Products of Digestion - GPD– combustible gasses that escape during digestion

– mainly methane, traces of H, CO, H2S

Urinary Energy - UE– loss of spent metabolites and energy through

urine

Energy Measures

Metabolizable Energy - ME– referred to as usable portion of ingested energy– DE - UE - GPD = ME

Heat Increment - HI– heat derived from metabolism or fermentation

of feedstuffs

Detergent Method

Energy– NEm

– NEg

– NEl

These values are calculated from ADF and NDF

Net Energy - NE

Net Energy computed by ME - HI Includes the amount of energy used for

maintenance plus some production component

NEM

– amount of energy expended to maintain energy equilibrium

Net Energy

NEM

– basal metabolism– energy of voluntary activity– warming of body– cooling of body

Net Energy for some production function

Energy Measurements

Common Feeds

Carbonaceous Concentrates– High in Energy– Low in fiber– Low in Protein– Variable in protein quality– fair in P– low in Ca

Concentrates

Corn– high energy– 8 - 9 % CP– Low in Lysine

Sorghum Grain– Must be processed– lower in energy than corn– higher in CP than corn

Concentrates

Oats– 75 - 85% energy of corn– very palatable– higher in fiber than corn

Beet Pulp Molasses

Concentrates

Citrus Pulp Animal Fat Cookie Meal

Protein Feeds

Soybean meal– low in Ca– most complete in energy and protein

Cottonseed meal Peanut Meal

High Moisture Feedstuffs

Green Chop - forage chopped in the field and fed without further processing

Silage - forage cut wet and put through controlled fermentation

Vitamins and Minerals

Add Vitamins to assure adequate amounts Mineral supplementation

– all minerals are not created equal– greater absorption of sulfates over oxides– example CuS vs CuO

Feed Additives

Antibiotics– Chlortetracycline– AS700

Growth Stimulants– ionophores - Bovatec, Rumensin

Others– MGA - used to stop heat

Problems Associated with Grain Feeding

Non Ruminants

Enteritis– Characterized by inflammation of stomach and

possibly SI– Antibiotics in starter rations can control this to

some degree Dietary changes, erratic feed intake and

weaning stress Also grain overload or highly fermentable

feeds

Non Ruminants

Laminitis (founder) Inflammation of the laminae Typically a result of poor grain/fiber

balance Excessive grain consumption results in

excessive lactic acid production

Ruminants

Enterotoxemia – over eating disease– Increase in clostridial organisms

Severe kidney damage and pin-point hemorrhages in intestine

Clostridial vaccination

Ruminants

Lactic acidosis – grain overload Overgrowth of bacteria which prefer lower

pH environment These are the starch digesting bacteria As they increase pH drops further Primarily due to their production of lactic

acid

Ruminants

If unchecked acids can be absorbed into the bloodstream resulting in metabolic acidosis

Endotoxins and histamine can result in founder

Liver abcesses Acidosis can occur in either acute or

chronic form

Polioencephalomalacia (PEM)

Primarily caused by over eating grain Organism in grain causes ruminal

production of Thiaminase Causes an acute thiamin deficiency Other PEMs can occur by intakes of high

sulfate water or feed – This type is not responsive to thiamin treatment

What to watch for

Dairies – low butterfat Humping of back Kicking at stomach Altered intake Fever

What to watch for

Gut sounds and motility Rumen pH Cud chewing Feed sorting Hoof problems (softening, white line, sole

abcesses) General unhealthy appearance (eyes, ears

etc.)