Applying feed intake monitoring Applying feed intake monitoring systems into producer testing systems into producer testing programsprograms

Dr. Daryl R. Strohbehn

Extension Beef Specialist

Iowa Beef Center @ ISU

Why Feed Efficiency?Why Feed Efficiency?

With everything else equal or even less wouldn’t you rather have a more feed efficient sire?

Why Feed Efficiency?Why Feed Efficiency? Feed cost represents 60% of

the total cost in finishing cattle. (Fox @ 2002 BIF)

Feed cost represents 63% of total financial cost to run a beef cow. (Strohbehn, IA SPA results 2000-04)

A 10% improvement in feed efficiency can improve feedlot profits 43%. (Fox, et.al. 2001)

65-75% of total dietary energy cost in breeding cows is required for maintenance. (Ferrell & Jenkins 1985; NRC 1996)

A 5% improvement in feed efficiency has an economic impact 4 times greater than a 5% improvement in ADG. (Gibb & McAllister 1999)

Why Feed Efficiency?Why Feed Efficiency?

Environmental friendly cattle

Selection for improved feed efficiency will:– Lower methane

emissions by 9 to 12% (Okine, et.al. 2001)

– Reduce manure N, P and K production by 15-17% (Arthur, et.al. 2002)

Why Feed Efficiency?Why Feed Efficiency?

It’s a heritable trait.

TraitHeritability

Feed conversion (f/g) .36

Feed efficiency (g/f) .42

Feed intake .41

Koots, et.al. 1994

Feed Conversion = Feed Intake / Animal Gain

Example - 4:1 or 8:1 (lbs of dry matter / lb gain)

Feed Efficiency = Animal Gain / Feed Intake

Examples: .25 lbs gained / lb feed or .125 lbs gain / lb feed

Efficiency Traits – Let’s get our definitions straight

(usually expressed in units of 100% dry matter)

Later on I will talk about RFI, NFI and NFE.

I remember when….1960-70’sI remember when….1960-70’s

Individual fed bulls in separate pens– Example: Wye Plantation in Queenstown,

Maryland Daily hand kept written records Very, very high labor No animal peck order, thus no impact

from competition

<-PinPointer 4000 system

Technology Advancements

Calan Electronic Feed Gates

- Each animal has its own space and daily written records

Technology Advancements

System at Circle A Angus, MO

GrowSafe GrowSafe System, CanadaSystem, Canada

Feed Conversion testing with Feed Conversion testing with on the farm/ranch systemson the farm/ranch systems Don’t take this job lightly

– It’s like milking dairy cows, methodical daily duties.

Requires attention to feed and management details, regardless of intake monitoring system utilized.

Requires meticulous record keeping, both with feed intake and weight gains.

Record analysis assistance Record analysis assistance may be needed.may be needed.

Feed conversion is just not feed intake divided by gain.

Most tests are equal time on feed, thus bull weights while on test vary a great deal.

BIF method: account for differences in average bull weights during test.

Range in off test weight: 974 - 1541

BIF MethodologyBIF Methodology

Adjusted Feed Conversion uses metabolic weights.– ( W.75 / Wi

.75 ) x ( Feed / Gain )

– W is the mid test weight; the average of the initial weight and final weight.

– This method adjusts feed/gain of heavier than average bulls downward and lighter than average bulls upward.

Question ???Question ??? Two bulls have the same Feed Conversion and 3.5 lb ADGs on

120 day test.– 6.5 lbs feed to 1.0 lb gain– Bull A and B have off test weights of 1300 and 1200, respectively.– Are they the same for Feed Conversion?

NO !– After adjusting for differences in body weight– Bull A’s average test weight was 1090 lbs, Bull B’s average test weight

was 990 lbs» Bull A Adjusted FC=6.27

» Bull B Adjusted FC=6.74

Beef Improvement Federation Guidelines

Duane Warden

Warden’s Ironwood Angus

Council Bluffs, IA

24 years of feed efficiency testing using

PinPointer system

Warden’s Adjusted Feed Conversion 1995-2004

y = -0.2021x + 7.6846

R2 = 0.3845

4

4.5

5

5.5

6

6.5

7

7.5

8

1995 1997 1999 2000 2001 2002 2003 2004

Warden’s Adjusted Feed Conversion 1995-2004

y = -0.2021x + 7.6846

R2 = 0.3845

4

4.5

5

5.5

6

6.5

7

7.5

8

1995 1997 1999 2000 2001 2002 2003 2004

701bull

New Levelbull

0350bull

4 Point 8bull

3303bull

4333bull

Influence sires – Past and Present

Warden’s Adjusted Feed Conversion 1995-2004

y = -0.2021x + 7.6846

R2 = 0.3845

4

4.5

5

5.5

6

6.5

7

7.5

8

1995 1997 1999 2000 2001 2002 2003 2004

701bull

New Levelbull

0350bull

4 Point 8bull

Warden Smarts

Sire Adj Feed Conversion

701 5.84

New Level 5.02

0350 5.18

4 Point 8 4.82

3303 5.21

4333 5.18

3303bull

4333bull

Warden’s Adjusted Feed Conversion 1995-2004

y = -0.2021x + 7.6846

R2 = 0.3845

4

4.5

5

5.5

6

6.5

7

7.5

8

1995 1997 1999 2000 2001 2002 2003 2004

701bull

New Levelbull

0350bull

4 Point 8bull

Warden Smarts

Sire RFI

701 -.70

New Level -2.20

0350 -1.33

4 Point 8 -2.61

3303 -1.06

4333 -2.50

3303bull

4333bull

Over 40 Years AgoOver 40 Years Ago

Dr. Robert Koch, U of Nebraska research and reported on a new system that adjusted feed intakes for body weight and growth.

Splits feed intake into two portions– 1. feed intake for a given level

of growth & size– 2. a residual portion

Data from:

-Lincoln, NE

-Fort Robinson, NE

-Fort Reno, OK

Breeds:

Angus

Hereford

Shorthorn

Thus was born RFIThus was born RFI(Residual Feed Intake)(Residual Feed Intake)

RFI is also known as:– NFI: Net Feed Intake– NFE: Net Feed Efficiency

RFI is the difference between a bull’s actual feed intake and its expected feed intake based on its size and growth.

RFI = actual DMI – expected DMI Heritability estimates 29% to 46%

RFIRFI(Residual Feed Intake)(Residual Feed Intake)

Used to identify animals that are either + or – from their expected ME intake.

-NFE = high efficiency +NFE = low efficiency

ADG

Wt.

Individual Bull

Expected DMI

Individual bull DMI

-NFE

Studies indicate RFI is an Studies indicate RFI is an independent traitindependent trait

Warden data no correlation between Off Test Weight and RFI

Relationship between RFI and Off Test WeightWarden Data: 1987-2005 (n=316 hd.)

-6.00

-4.00

-2.00

0.00

2.00

4.00

6.00

900 1100 1300 1500

Off Test Weight

RFI

r = -.02

Studies indicate RFI is an Studies indicate RFI is an independent traitindependent trait

Warden data no correlation between ADG and RFI.

Relationship between RFI and ADG Warden Data: 1987-2005 (n=316 hd.)

2.50

3.00

3.50

4.00

4.50

5.00

5.50

-6.00 -4.00 -2.00 0.00 2.00 4.00 6.00

RFI

ADG

r = -.01

Studies indicate RFI is an independent trait, Studies indicate RFI is an independent trait, but related to Adjusted Feed Conversionbut related to Adjusted Feed Conversion

Warden data .46 correlation between Adjusted Feed Conversion and RFI

Relationship between RFI and Adjusted Feed Conversion

4

5

6

7

8

9

10

-5.00 -3.00 -1.00 1.00 3.00 5.00

NFI

AFE

r = .46

RFI

Studies indicate RFI is an independent Studies indicate RFI is an independent trait, but related to Dry Matter Intaketrait, but related to Dry Matter Intake

Warden data .55 correlation between Dry Matter Intake and RFI.

Relationship between RFI and Dry Matter Intake

18.00

20.00

22.00

24.00

26.00

28.00

30.00

32.00

34.00

-5.00 -3.00 -1.00 1.00 3.00 5.00

RFI

DMI

r = .55

Other relationships were Other relationships were evaluated….evaluated….

A significant correlation between RFI and ultrasound fat cover existed (.17)– Means fatter bulls were less

efficient No significant relationships

existed between RFI and other performance parameters.– EPDs (BW, WW, YW, Milk)

and ultrasound REA

Dilemma with calculating RFIDilemma with calculating RFI Requires doing a regression

analysis of the data to develop an equation called Expected Dry Matter Intake.

Expected Dry Matter Intake is then used against Actual Dry Matter Intake to develop the RFI.

Not many producers have the expertise and knowledge of statistics to do this exercise.

Going to require serious expertise involvement either from Extension Service or Breed Association.

Warden-Beedle information gathering system using off the shelf electronic components.

Joint project with the Iowa Beef Center, Miraco, ID-ology, and Rice Lake Scales

Our Future…..Let’s Hope.

A view from Australia on the possibilities

Angus NFI Percentile