Forage Quality: Making Sense Out of Your Alphabet

Soup

Forage Quality: Making Sense Out of Your Alphabet

Soup

Dennis Hancock, PhD.Extension Forage Specialist

UGA – Dept. of Crop and Soil Sciences

Dennis Hancock, PhD.Extension Forage Specialist

UGA – Dept. of Crop and Soil Sciences

Outline

•What is forage quality?

•What do all those terms mean?

•Can you give me one number to look at?

•How do I use forage quality data?

•What affects forage quality?

Which is the better hay?Which is the better hay?

Which is the better hay?Which is the better hay?

How good is this hay?

Crude Protein = 13.5%

How good is this hay?

Crude Protein = 13.5%

Crude Protein and Hay Quality

Crude Protein and Hay Quality

• CP is the most overrated measure of quality! Total N x 6.25 = CP, %

• Tells you nothing about the form nitrogen is in Protein (AA), Bound Protein, Nitrates etc.

• Protein requirements are (typically) easily met

• Somewhat related to maturity

• Tells you very little about energy content

• Important- just overemphasized

• CP is the most overrated measure of quality! Total N x 6.25 = CP, %

• Tells you nothing about the form nitrogen is in Protein (AA), Bound Protein, Nitrates etc.

• Protein requirements are (typically) easily met

• Somewhat related to maturity

• Tells you very little about energy content

• Important- just overemphasized

How do we get enough energy in the animal?

How do we get enough energy in the animal?

• The animal eats more forage. What is the physical limit? Can a cow eat enough straw to meet her energy

needs?

• What forage the animal eats must be high in energy. High digestibility -> High energy

• Bottomline: Every bite has to count!

• The animal eats more forage. What is the physical limit? Can a cow eat enough straw to meet her energy

needs?

• What forage the animal eats must be high in energy. High digestibility -> High energy

• Bottomline: Every bite has to count!

The Relationship between Fiber (NDF) and Dry Matter Intake (DMI)

The Relationship between Fiber (NDF) and Dry Matter Intake (DMI)

Fiber (NDF) Level

Inta

ke

Intake toMeet Needs

Intake is Physically Limited

Dry Matter Intake (DMI)

Dig. Energy Intake

Low Digestibility High Digestibility

What is high quality forage?What is high quality forage?

• Forage that is highly digestible (i.e., high TDN) and large amounts of the forage can be consumed (i.e., high DMI).

= High Quality Forage

• Relative Forage Quality (RFQ) = TDN * DMI/1.23

• Forage that is highly digestible (i.e., high TDN) and large amounts of the forage can be consumed (i.e., high DMI).

= High Quality Forage

• Relative Forage Quality (RFQ) = TDN * DMI/1.23

The Plant CellThe Plant Cell

Cell Contents

Cell Wall

The Plant CellThe Plant Cell

PectinsHemicelluloseCelluloseLigninSilica

ProteinOilMineralsSugarsOrganic Acids

Easily Digestible

Neutral Detergent FiberCell Contents

Cell Wall

The Plant CellThe Plant Cell

HemicelluloseCelluloseLigninSilica

Neutral Detergent FiberCell Contents

Cell Wall

The Plant CellThe Plant Cell

CelluloseLigninSilica

Cell Contents

Cell Wall Acid Detergent Fiber

Acid Detergent Lignin

The Plant CellThe Plant Cell

Silica (& Minerals)Cell Contents

Cell Wall

Ash

The Plant CellThe Plant Cell

PectinsHemicelluloseCelluloseLigninSilica

ProteinOilMineralsSugarsOrganic Acids

Easily Digestible

Neutral Detergent FiberCell Contents

Cell Wall

3 Primary Components• Cellulose

“Concrete Blocks”

• Hemicellulose “Red Bricks”

• Lignin “Rebar and the Mortar”

Fiber = Cell WallFiber = Cell Wall

Neutral Detergent Fiber

Acid Detergent Fiber

Lignin

It is the relative amount of each that is important.

Fiber = Cell WallFiber = Cell Wall

The Plant CellThe Plant Cell

HemicelluloseCelluloseLignin

Amt. & Ratio of Each

Total Digestible NutrientsRelative Forage Quality

(RFQ)Metabolizable Energy

Dry Matter Intake

What can you make out of Crude Fiber?

• Crude fiber makes no allowance for the ratios of cellulose, hemicellulose, and lignin (relative to one another).

• Crude fiber makes no distinction between forage species and different fiber types.

• Crude fiber makes no allowance for the ratios of cellulose, hemicellulose, and lignin (relative to one another).

• Crude fiber makes no distinction between forage species and different fiber types.

Feeding the Dairy Herd:http://www.extension.umn.edu/distribution/livestocksystems/DI0469.html

• Section: Feed Nutrientshttp://www.extension.umn.edu/distribution/livestocksystems/components/DI0469-03.html

What can you make out of Crude Fiber?

• Crude fiber is not an accurate measure of total fiber Much of the lignin and hemicellulose

(and some cellulose) is lost during the analysis.

1890s technology!

• Most testing labs no longer report CF. It is required on tags of purchased

feeds.

• Crude fiber is not an accurate measure of total fiber Much of the lignin and hemicellulose

(and some cellulose) is lost during the analysis.

1890s technology!

• Most testing labs no longer report CF. It is required on tags of purchased

feeds.

Feeding the Dairy Herd:http://www.extension.umn.edu/distribution/livestocksystems/DI0469.html

• Section: Feed Nutrientshttp://www.extension.umn.edu/distribution/livestocksystems/components/DI0469-03.html

What is high quality forage?What is high quality forage?

• Forage that is highly digestible (i.e., high TDN) and large amounts of the forage can be consumed (i.e., high DMI).

= High Quality Forage

• Relative Forage Quality (RFQ) = TDN * DMI/1.23

• Forage that is highly digestible (i.e., high TDN) and large amounts of the forage can be consumed (i.e., high DMI).

= High Quality Forage

• Relative Forage Quality (RFQ) = TDN * DMI/1.23

RFQ Simplifies ComparisonsRFQ Simplifies Comparisons• Relative Forage Quality

Predicts energy based on fiber quality and intake

• Combined into a single value RFQ of 100 is ~ = full-bloom

alfalfa Could simplify marketing RFQ allows comparisons to be

made across forage species Allows hay to be easily assigned

to appropriate physiological stages

• Relative Forage Quality Predicts energy based on fiber

quality and intake

• Combined into a single value RFQ of 100 is ~ = full-bloom

alfalfa Could simplify marketing RFQ allows comparisons to be

made across forage species Allows hay to be easily assigned

to appropriate physiological stages

Range in Appropriate

RFQs

Range in Appropriate

RFQs

Common Questions about Interpreting and Using Forage

Quality Data

Reading Forage Quality Data

Reading Forage Quality Data

1

2

3

Price

4

Let’s Do Some Comparisons

A

B

C

Nutrient Requirements: 1200 lb cow*

Nutrient Requirements: 1200 lb cow*

Req.

TDN 58.1%

CP 9.6%* First 3-4 mo postpartum,

prep to rebreed

Comparing One Lot of Hay To Another

Lot ID A B C

Kind of Hay Tift 85 TF/OG Coast

RFQ 96.2 109.7 118.5

CP, % 10.7 14.6 14.3

NDF, % 65.8 58.5 56.1

ADF, % 40.6 36.2 32.7

Lignin, % 7.0 6.6 4.8

TDN, % 52.8 56.9 61.2

Which lot is best for our lactating beef cow?Which lot is best for our lactating beef cow?

Req.

TDN 58.1%

CP 9.6%* First 3-4 mo postpartum,

prep to rebreed

Comparing One Lot of Hay To Another

Lot ID A B C

Kind of Hay Tift 85 TF/OG Coast

RFQ 96.2 109.7 118.5

CP, % 10.7 14.6 14.3

NDF, % 65.8 58.5 56.1

ADF, % 40.6 36.2 32.7

Lignin, % 7.0 6.6 4.8

TDN, % 52.8 56.9 61.2

Price, $/ton 140 140 135

Which lot is best for our lactating beef cow?Which lot is best for our lactating beef cow?

Req.

TDN 58.1%

CP 9.6%* First 3-4 mo postpartum,

prep to rebreed

What is the value of forage quality?

What is the value of forage quality?

$65/1000 lb roll51% TDN

$70/1000 lb roll58% TDN

A)

B)

Scenario: Lact. Cows• Bale A cost:

No supplement; $70/bale

• Bale B cost: 180 lbs of supplement/1000 lb

bale $15.75 supp. + $65 =

$80.75 + labor

In this case, the feeding of one bale paid for the forage

test.

Thou Shalt Test Your Forages

Thou Shalt Test Your Forages

NIR CuvetteNIR Cuvette

Cost Comparison (UGA)Cost Comparison (UGA)

Measurement NIR Wet Chemistry

CP, NDF, RFQ, TDN, NEm, NEg, NEl, Moisture

$8 $21

+ Nitrate $10 $23

+ Minerals $20 $28

+ ADF No charge $38

+ Lignin No Charge $53

What Affects Forage Quality?What Affects Forage Quality?

Primary Factors Affecting Forage Quality

Primary Factors Affecting Forage Quality

Factor Recommendation

Plant Maturity Cut bermudagrass every 4-5 wks; cut tall fescue in the boot or early head stage.

Forage Species Use the highest-quality grass species that will persist in your environment.

Bale Storage Protect bales from rainfall and weathering during storage (i.e., barn, tarp, etc.)

Rain During Curing

Avoid cutting if significant rainfall (> 0.50 inches) is predicted during curing.

Moisture at Baling

Allow forage to dry to the appropriate moisture (Round: 15%; Square: 18%)

Fertilization Provide fertilizer based on soil test recommendations

Variety Use varieties that have proven to be higher in quality.

The Paradox of Forage Quality and Quantity

Days of Growth

0 5 10 15 20 25 30 35 40 45 50

For

age

Mas

s(d

ry lb

s/a

cre

)

0

2000

4000

6000

8000

10000

12000Growth Curve

Digestibility & Palatability

Bermudagrass Harvest Interval

Effects on Protein and Digestibility

McCollough and Burton., 1962DMI 11.9, 8.8, 9.5 lbsADG 1.2, .9, 0 lbsOat straw = ~ 43 TDN

15.8

6.3 5.3

55.049.0

45

0

10

20

30

40

50

60

Crude Protein Digestibility

4 weeks 8 weeks 13 weeks

The Effect of Maturity on the Bottomline: Supplementing a

Lactating Cow

The Effect of Maturity on the Bottomline: Supplementing a

Lactating Cow

Crop Maturity CP TDNSuppleme

nt Cost

-- % -- -- % -- lbs/hd/day $/hd/day

Bermudagrass

4 weeks 10-12 58-62 0 $0

6 weeks 8-10 51-55 4.8 $0.45

8 weeks 6-8 45-50 7.5 $0.72+ ~$2.00/hd/d

Primary Factors Affecting Forage Quality

Primary Factors Affecting Forage Quality

Factor Recommendation

Plant Maturity Cut bermudagrass every 4-5 wks; cut tall fescue in the boot or early head stage.

Forage Species Use the highest-quality grass species that will persist in your environment.

Bale Storage Protect bales from rainfall and weathering during storage (i.e., barn, tarp, etc.)

Rain During Curing

Avoid cutting if significant rainfall (> 0.50 inches) is predicted during curing.

Moisture at Baling

Allow forage to dry to the appropriate moisture (Round: 15%; Square: 18%)

Fertilization Provide fertilizer based on soil test recommendations

Variety Use varieties that have proven to be higher in quality.

Quality Differences in the Major Forage Species

Quality Differences in the Major Forage Species

40

50

60

70

80

Dig

estib

le D

M, %

Trop

ical Annual

Grasses

Cool S

eason P

erennial

G

rasses

Cool S

eason A

nnual G

rasses

Leg

um

es

Trop

ical Peren

nial

Grasses

Maint.

Mod. Production

High Production

Primary Factors Affecting Forage Quality

Primary Factors Affecting Forage Quality

Factor Recommendation

Plant Maturity Cut bermudagrass every 4-5 wks; cut tall fescue in the boot or early head stage.

Forage Species Use the highest-quality grass species that will persist in your environment.

Bale Storage Protect bales from rainfall and weathering during storage (i.e., barn, tarp, etc.)

Rain During Curing

Avoid cutting if significant rainfall (> 0.50 inches) is predicted during curing.

Moisture at Baling

Allow forage to dry to the appropriate moisture (Round: 15%; Square: 18%)

Fertilization Provide fertilizer based on soil test recommendations

Variety Use varieties that have proven to be higher in quality.

Primary Factors Affecting Forage Quality

Primary Factors Affecting Forage Quality

Factor Recommendation

Plant Maturity Cut bermudagrass every 4-5 wks; cut tall fescue in the boot or early head stage.

Forage Species Use the highest-quality grass species that will persist in your environment.

Bale Storage Protect bales from rainfall and weathering during storage (i.e., barn, tarp, etc.)

Rain During Curing

Avoid cutting if significant rainfall (> 0.50 inches) is predicted during curing.

Moisture at Baling

Allow forage to dry to the appropriate moisture (Round: 15%; Square: 18%)

Fertilization Provide fertilizer based on soil test recommendations

Variety Use varieties that have proven to be higher in quality.

Primary Factors Affecting Forage Quality

Primary Factors Affecting Forage Quality

Factor Recommendation

Plant Maturity Cut bermudagrass every 4-5 wks; cut tall fescue in the boot or early head stage.

Forage Species Use the highest-quality grass species that will persist in your environment.

Bale Storage Protect bales from rainfall and weathering during storage (i.e., barn, tarp, etc.)

Rain During Curing

Avoid cutting if significant rainfall (> 0.50 inches) is predicted during curing.

Moisture at Baling

Allow forage to dry to the appropriate moisture (Round: 15%; Square: 18%)

Fertilization Provide fertilizer based on soil test recommendations

Variety Use varieties that have proven to be higher in quality.

Primary Factors Affecting Forage Quality

Primary Factors Affecting Forage Quality

Factor Recommendation

Plant Maturity Cut bermudagrass every 4-5 wks; cut tall fescue in the boot or early head stage.

Forage Species Use the highest-quality grass species that will persist in your environment.

Bale Storage Protect bales from rainfall and weathering during storage (i.e., barn, tarp, etc.)

Rain During Curing

Avoid cutting if significant rainfall (> 0.50 inches) is predicted during curing.

Moisture at Baling

Allow forage to dry to the appropriate moisture (Round: 15%; Square: 18%)

Fertilization Provide fertilizer based on soil test recommendations

Variety Use varieties that have proven to be higher in quality.

Primary Factors Affecting Forage Quality

Primary Factors Affecting Forage Quality

Factor Recommendation

Plant Maturity Cut bermudagrass every 4-5 wks; cut tall fescue in the boot or early head stage.

Forage Species Use the highest-quality grass species that will persist in your environment.

Bale Storage Protect bales from rainfall and weathering during storage (i.e., barn, tarp, etc.)

Rain During Curing

Avoid cutting if significant rainfall (> 0.50 inches) is predicted during curing.

Moisture at Baling

Allow forage to dry to the appropriate moisture (Round: 15%; Square: 18%)

Fertilization Provide fertilizer based on soil test recommendations

Variety Use varieties that have proven to be higher in quality.

What is New?What is New?

Dennis Hancock, PhD.Extension Forage Specialist

UGA – Dept. of Crop and Soil Sciences

Dennis Hancock, PhD.Extension Forage Specialist

UGA – Dept. of Crop and Soil Sciences

VarietiesVarieties

• UF Riata Improved bahiagrass, similar to Tifton 9 Better cold tolerance, longer growing

season Seed production beginning in 2009 (in GA).

• New Novel Endophyte Tall Fescues Arkansas releases UGA, UK, and Noble Foundation

• UF Riata Improved bahiagrass, similar to Tifton 9 Better cold tolerance, longer growing

season Seed production beginning in 2009 (in GA).

• New Novel Endophyte Tall Fescues Arkansas releases UGA, UK, and Noble Foundation

HerbicidesHerbicides

• OutRider (previously known as Maverick) Johnsongrass control

• Prowl H2O Label expected in July 2009 PRE crabgrass control (applied in Feb./early

Mar)

• DuPont has 2 good ones in the pipeline ‘Pastora’ label in late 2009?

Ryegrass and broadleaf control in bermuda Another for crabgrass/johnsongrass control

• OutRider (previously known as Maverick) Johnsongrass control

• Prowl H2O Label expected in July 2009 PRE crabgrass control (applied in Feb./early

Mar)

• DuPont has 2 good ones in the pipeline ‘Pastora’ label in late 2009?

Ryegrass and broadleaf control in bermuda Another for crabgrass/johnsongrass control

Current Research Overview

Current Research Overview

• N volatilization study (Calhoun/Eatonton)• Ryegrass baleage feeding trial (Calhoun)• Rye-Ryegrass growth curves

(Athens/Tifton)• Growth of forage brassicas (Athens)• Drying rates of SA grasses (Athens)• Pearl millet planting date (Athens)• Teff N response (Athens)• Switchgrass agronomics (Athens/Midville)• Clover management zones (Eatonton)

• N volatilization study (Calhoun/Eatonton)• Ryegrass baleage feeding trial (Calhoun)• Rye-Ryegrass growth curves

(Athens/Tifton)• Growth of forage brassicas (Athens)• Drying rates of SA grasses (Athens)• Pearl millet planting date (Athens)• Teff N response (Athens)• Switchgrass agronomics (Athens/Midville)• Clover management zones (Eatonton)

Current Research Overview

Current Research Overview

• DuPont herbicide trials (1: Calhoun; 4 Eatonton)

• On-farm Research on MiG Dairying (Wrens and Quitman) Forage species growth under IRR and MIG

Quality, Yield, and Distribution IRR scheduling for MIG Fate of N on MIG

• DuPont herbicide trials (1: Calhoun; 4 Eatonton)

• On-farm Research on MiG Dairying (Wrens and Quitman) Forage species growth under IRR and MIG

Quality, Yield, and Distribution IRR scheduling for MIG Fate of N on MIG

Current Research Overview

Current Research Overview

Variety Trials• Alfalfa (Athens, Midville, Tifton)• Cool Season Perennial Legumes (Athens,

Calhoun, Eatonton)• Cool Season Perennial Grasses (Athens,

Blairsville, Calhoun, Eatonton)• Chicory (Athens)

Variety Trials• Alfalfa (Athens, Midville, Tifton)• Cool Season Perennial Legumes (Athens,

Calhoun, Eatonton)• Cool Season Perennial Grasses (Athens,

Blairsville, Calhoun, Eatonton)• Chicory (Athens)

Strategies for Tight Budgets and Minimal Risk

Regional Forage Trainings - 2009

Across Georgia (4) and South Carolina (3)

Strategies for Tight Budgets and Minimal Risk

Regional Forage Trainings - 2009

Across Georgia (4) and South Carolina (3)

www.georgiaforages.com

Hay ProductionSchool 2009

April 21 UGA – Griffin Campus

Hay ProductionSchool 2009

April 21 UGA – Griffin Campus

www.georgiaforages.com

Corn Silage and Conserved Forage Field Day

June 18 UGA-Tifton

www.georgiaforages.com

Grazing School 2009September 22-23

UGA-Athens Livestock Arena

Grazing School 2009September 22-23

UGA-Athens Livestock Arena

www.georgiaforages.com

QUESTIONS?QUESTIONS?

www.georgiaforages.com1-800-ASK-UGA1

www.georgiaforages.com1-800-ASK-UGA1