feed efficiency, rfi and the benefits for the beef industrydepartment/deptdocs.nsf/all/lr...feed...

Feed Efficiency, RFI and the

Benefits for the Beef Industry

J.A. Basarab, P.Ag., Ph.D. Alberta Agriculture and Rural Development

Lacombe Research Centre, Alberta, Canada

Tiffin Conference, Cattle Gate to Dinner Plate

19 January 2012, Lethbridge, Alberta

Feed Efficiency in Beef Cattle: Why?

56-71% of total cost of production for cow-calf operations

is associated with feed, bedding and pasture

(Alberta Agriculture and Rural Development 2005)

65-75% of the total dietary energy cost in breeding cows

is required for maintenance (Ferrell & Jenkins 1985; NRC 1996)

Genetic improvement in feed efficiency - estimated:

$50-100 million annually to Alberta’s beef cattle industry

Energetic Efficiency in growing beef cattle

1. Feed Intake

2. Feed Conversion Ratio: DMI/ADG;

CV for DMI, 8-12%; CV for ADG, 16-20%

3. Partial Efficiency of growth: ADG/(avg. DMI-expected DMIm)

efficiency of growth after removing FI for maintenance

4. Relative Growth Rate: 100 x [log end wt – log start wt]/days on test

Growth relative to instantaneous body size

5. Kleiber Ratio: ADG/avg test period LWT 0.75

weight gain per unit of metabolic body weight

All measures are related to body size, growth

and composition of gain

Maintenance requirements of beef cattle is largely

unchanged over last 100 years (Johnson, Ferrell and Jenkins, 2003)

CH4 NH3 N2O GWP100

Chickens – layers -30 -36 -29 -25

Chickens – broilers -20 10 -23 -23

Pigs -17 -18 -14 -15

Cattle – dairy -25 -17 -30 -16

Cattle – beef 0 0 0 0

Sheep -1 0 0 -1

% Change in greenhouse gas emissions and global

warning potential achieved through genetic

improvement (1988-2007)

Sources: Project for DEFRA by Genesis Faraday Partnership and Cranfield University

(AC0204) from Hume et al. (2011), J. Ag. Sci., doi:10.1017/S0021859610001188 .

Pork 2.8-4.5 kg CO2e/kg pork; chicken 1.9-2.9 kg CO2e/kg chicken; Dairy 1.3 kg CO2e/kg milk

Beef 18-36 kg CO2e/kg beef

Calf-fed, Hormone FreeAn imal GHG emissio n s = 9 2 2 ,1 0 7 k g CO2 e

Figure 1. Breakdown of total greenhouse gas (GHG) emissions resulting from hormone free and growth implanted

calf-fed and yearling-fed beef production systems (CO 2 equivalents, 160 cow-herd assumed).

Calf-fed, growth implantedAn imal GHG emissio n s = 9 2 8 ,3 4 4 k g CO2 e

Yearling-fed, Hormone FreeAn imal GHG emissio s = 1 ,2 1 9 ,6 5 9 k g CO2 e

Yearling-fed, Growth ImplantedAn imal GHG emissio n s = 1 ,2 3 7 ,0 8 2 k g CO2 e

Total GHG emissions include methane from enteric fermentation and manure, nitrous oxide from manure, carbon dioxide from energy use and nitrous oxide from cropping.

Productive cow

70.0%

Productive cow

69.6%

Productive cow

53.0%Productive cow

52.2%

Feeder 15.1%

Replacement bulls 1.3%

Spring culled cows 3.9%

Fall culled cows 3.1%

Replacement heifers 3.4%

Herd bulls 3.5%

Feeder 14.5%





Herd bulls 3.6%

Feeder 35.4%





Herd bulls 2.7%

Feeder 36.3%





Herd bulls 2.7%

37 131

8 17 134

17560

9 316

049

3 61 827

1 16 328 9 8124

8 4 43 86 597

928 20 24

9 54 643 31 15 16

5 1 5

Bull ID

-5

-4

-3

-2

-1

0

1

2

3

4

RF

I, k

g a

s fe

d/d

ay

+RFI Mid RFI -RFI

Olds College; 96 British bulls (2003-05)

Cost difference: -RFI vs. +RFI

3.0 kg as fed/day x $0.15/kg x 140 days = $63

Diet (as fed basis): 76% barley silage; 30% barley grain & 3% beef sup. (32 % CP)

Residual Feed Intake (RFI) also called Net Feed Efficiency:

FEED INTAKE ADJUSTED FOR BODY SIZE AND PRODUCTION - growing cattle

is the difference between an animal's actual feed intake & its expected feed

requirement for maintenance of body weight, growth and changes in fatness.

- moderately heritable

(h2 = 0.29-0.46)

- reflects an animal’s

energy requirement

for maintenance.

Energetic Efficiency in growing beef cattle

148 steers from 5 genetic strains fed a finishing diet and gaining 1.52 kg/day . No relationship to slaughter

weight, hip height and gain in hip height (Basarab et al. 2003).

rp = 0.00

P = 0.99

rp = 0.00

P = 0.99

Selection for low RFI will:

1. Have no effect on growth & animal size Phenotypic (rp) & genetic correlations (rg) are near zero Arthur et al. 2001; Basarab et al. 2003; Crews et al. 2003; Jensen et al. 1992

2. Reduce feed intake by 10-12% at equal body size & ADG rp = 0.60-0.72; rg = 0.69-0.79 (Arthur et al. 2001; Basarab et al. 2003, 2007,

2011;Herd et al. 2002)

-2 -1.5 -1 -0.5 0 0.5 1 1.5

Residual feed intake, kg DM/hd/day

5

6

7

8

9

10

DM

I, k

g/h

d/d

ay

73 hybrid bulls

Olds College,

Fall 2006

rp = 0.64

3. Improve Feed Conversion Ratio (FCR) by 9-15% at

equal body size & average daily gain rp=0.53-0.70; rg = 0.66-0.88; Arthur et al. 2001; Basarab et al. 2003, Herd et al. 2002

148 steers

rp = 0.43

Lacombe

-5 -4 -3 -2 -1 0 1 2 3 4 5

RFI, kg as fed/day

3

4

5

6

7

8

FC

R,

kg D

MI/k

g g

ain

4. No effect on carcass fat provided RFI is adjusted

for fatness (Basarab et al. 2003; Nkrumah et al. 2007)

Phenotypic (rp) & genetic correlations (rg) are inconsistent

& near zero (0.20 to –0.20)

Classical Serial Slaughter Study: Total whole body composition (water, fat, protein, ash

& energy); MEI = Retained energy + Heat Production

Liver weight: 7.8% LOW RFI (P=0.007)

Stomach complex: 7.6% LOW RFI (P=0.004)

Heat production: 9.3% LOW RFI (P<0.001)

5. Lower heat production by 9-10% (MEI=RE+HP; HP=NEm + HIF)

Basarab et al. 2003; Nkrumah et al. 2007

1.00

1.20

1.40

1.60

1.80

2.00

2.20

2.40

2.60

2.80 8.5

- 9

.0

9.5

- 1

0.0

10.5

- 1

1.0

11.5

- 1

2.0

12.5

- 1

3.0

13.5

- 1

4.0

14.5

- 1

5.0

15.5

- 1

6.0

16.5

- 1

7.0

17.5

- 1

8.0

18.5

- 1

9.0

19.5

- 2

0.0

20.5

- 2

1.0

21.

5 -

22.0

22.5

- 2

3.0

23.5

- 2

4.0

Time (0.5 hr)

Oxyg

en

co

nsu

mp

tio

n (

L/

min

)

LOW or -RFI

MEDIUM RFI

HIGH or +RFI

6. Lower methane emissions by 15-30% &

manure production by 15-20% Okine et al. 2001; Arthur et al. 2002; Nkrumah et al. 2007; Hegarty et al. 2007

0.000

0.040

0.080

0.120

0.160

0.2009

.0 -

9.5

10

.0 -

10

.5

11

.0 -

11

.5

12

.0 -

12

.5

13

.0 -

13

.5

14

.0 -

14

.5

15

.0 -

15

.5

16

.0 -

16

.5

17

.0 -

17

.5

18

.0 -

18

.5

19

.0 -

19

.5

20

.0 -

20

.5

21

.0 -

21

.5

22

.0 -

22

.5

23

.0 -

23

.5

0 .0

- 0

.5

Time (0.5 hr)

Me

tha

ne

pro

du

ctio

n (

L/m

in)

LOW or -RFI

MEDIUM RFI

HIGH or +RFI

Three Cross Ranch – 2007 breeding season

Mating Grp 1 +RFI -RFI

X 123 cows


X 121 cows


X 48 cows

Morison’s Feedlot – Jun – Sep 2009 Feed Intake test, 240 feeders

20

12

0S

WK

29

SJ

B3

8S

JB

41

8S

WK

10

3S

11

SJ

B9

4S

74

8S

DC

25

S4

5D

C1

9S

DC

27

S5

2S

AL

13

9S

38

50

S1

09

S9

1S

77

S4

23

14

14

93

49

6S

14

S3

91

75

1 2 91

02

42

25

64

16

S4

03

32

51

08

S1

12

S4

20

S2

03

32

63

54

88

12

17

4S

18

06

7S

40

S1

11

51

23

S3

22

9A

L1

50

SJ

B1

01

SW

K2

0S

WK

98

SD

C2

4S

46

WK

11

4S

40

3S

JB

87

SJ

B6

8S

JB

24

S6

96

7

Bull ID

-2

-1.5

-1

-0.5

0

0.5

1

1.5

RF

I, k

g D

M/d

ay

Distribution of Residual Feed Intake (RFI) for TX BeefBooster

bulls tested from Dec 11/2006 to Mar 8/2007.

(barley silage:grain (60:40%) diet)

n=73, mean=0.00

SD= 0.506

R2 x 100 = 58.2%

9 -RFI

BULLS

9 +RFI

BULLS

7. No effect on bull fertility Wang, Ambrose, Colazo, Basarab et al., J. Anim. Sci. 2011

Traits n rp sign.

365-day SC, cm 404 0.01 NS

Front feet score 343 0.02 NS

Front leg score 274 -0.01 NS

Hind feet score 343 0.03 NS

Disposition score 343 -0.04 NS

Semen morphology 260 0.08 NS

Semen motility 260 0.14 *

Semen conc. score 260 -0.09 NS

Progeny produced (27 sires) 0.00 NS

Relationship (rp) between RFI and breeding

soundness in yearling beef bulls

No difference in culling reasons: 42.1% of +RFI & 41.5% -RFI bulls culled

3.7% reduction in DMI (0.35 kg DM/d/9.5 kg DM/d); cow 13 kg DM/d x 3.7% x $0.15/kg DM x 365 = $26/cow

-1.5 -1 -0.5 0 0.5 1

Sire phenotypic RFI, kg DM/day

-0.5

0

0.5

Average P

rogeny R

FI,

kg D

M/d

ay

y = 0.016 + 0.352x,

sire=13, R2 = 57.3%

0.352 kg DM/day x $0.30/kg DM x 150 days

= $15.84/hd

Relationship between sire phenotypic RFI and

average progeny phenotypic RFI (Three Cross Ranch)

Where r-square for growth curves was greater than 0.95 and progeny per sire is 2 or more.

Slope equal for slaughter heifers and steers.

Progeny performance Sires Sires

During finishing +RFI -RFI Sign.

Number of progeny 95 144

Progeny carcass weight, kg 366 372 NS

Progeny carcass grade fat, mm 11.0 11.3 NS

Progeny ribeye area, cm2 93.5 93.7 NS

Progeny marbling score 4.22 4.30 NS

Progeny yield grade 1.38 1.45 NS

Progeny lean meat yield, % 58.6 58.4 NS

NS, not significant, P>0.05

Effect of sire RFI on the carcass quality of their progeny

Individual Animal Feed Intake Facility, Lacombe Research Centre, AB, Canada

Cow productivity & reproductive fitness

56.6% barley straw:40.0% silage

3.4% Feedlot sup (32% CP)

ad libitum twice daily

30% straw:70% grass hay (DM basis)

9.6% CP, 8.75 MJ ME/kg DM

7 8 9 1 0 1 1 1 2 1 3 1 4 1 5 1 6

Age, mo

0

2 0

4 0

6 0

8 0

1 0 0

Cu

mu

lati

ve

% r

each

ing

pu

ber

ty

[-RFI] n=94

[+RFI] n=89

P = 0.03

P = 0.40

P = 0.34

P = 0.22

P = 0.29

P = 0.54

P = 0.99A.

8. No effect of RFIfat on age at puberty and pregnancy

A. Levels of significance are given for cumulative percent of heifers reaching puberty by

9, 10, 11, 12, 13, 14 and 15 mo of age. B. Levels of significance are given for cumulative

percent heifers pregnant by 2, 7, 12, 17, 22, 27, 32 and 37 d of the breeding season.

Adapted from Basarab et al. (2011).

0 1 0 2 0 3 0 4 0

Days from start of breeding season

0

2 0

4 0

6 0

8 0

1 0 0

Cu

mu

lati

ve

% p

reg

na

nt

(-RFI) n=94 (+RFI) n=96

P=0.49

P=0.76

P=0.47

P=0.68P=0.38

P=0.29

P=0.80

P=0.80

B.

0 1 0 2 0 3 0 4 0 5 0

Days from start of calving

0

2 0

4 0

6 0

8 0

1 0 0

Cu

mu

lati

ve

Per

cen

t (%

)

-RFI +RFI

9. No effect of calving pattern

RFI adj.

for fat

n= 75 n= 73

NS

NS

NS

NS

NS

Heifers exposed to breeding 98 92

Calving difficulty, % 6.7 9.2 NS

Total calf death, % 5.3 11.8

Calf death unknown, % 2.7 7.9

Weaning rate, % 71.4 71.7 NS

Birth weight, kg 36.6 36.5 NS

Pre-weaning ADG, kg/day 0.98 0.99 NS

Weaning weight, kg 251 255 NS

Heifer productivity, kg/hd/yr 186 191 NS

Heifer RFI fat

-RFI +RFI sign. Trait

Productivity traits in -RFI and +RFI first calf heifers

Basarab et al. 2011; improved early life survival 1) better uterine env. due to more available nutrients, and 2)

lower reactive oxygen species, proton leakage in mitochondria and oxidative stress at cell level.

LOW RFI cow J1042 (5 yr-old Hereford-Angus cow

in the spring of 2004; RFI adj = -2.64 kg as fed/day;

2003 weight at weaning =787 kg).

HIGH RFI cow E1245 (8 yr-old Hereford-Angus cow

in the spring of 2004; RFI adj = 2.83 kg as fed/day;

2003 weight at weaning = 755 kg).

10. No effect on pregnancy, calving or weaning rates

No effect on kg calf weaned/cow exposed to breeding (Arthur et al. 2005; Basarab et al. 2007)

Note: cow RFI was adjusted for conceptus weight

Long-term (1997 to 2006) ultrasound back fat thickness of cows that

produced -RFI and +RFI progeny

0 10 20 30 40 50 60 70 80 90 100 110 120

Months from January 1, 1997

0

2

4

6

8

10

12

14

16

18

Ult

ra

sou

nd

Ba

ck

fa

t th

ick

ne

ss,

mm

Progeny RFI <=-0.44 Progeny RFI >=0.44

W97

PC

PB

W98 PC

PB

PB

PB

PB

PB

PB

PB

PB

PC

PC

PC

PC

PCPC

PC

W99

W00

W01

W02

W03

W04

W05

W06

1997/98 1998/99 1999/00 2000/01 2001/02 2002/03 2003/04 2004/05 2005/06

1996/97

0 10 20 30 40 50 60 70 80 90 100 110 120

Months from January 1, 1997

550

600

650

700

750

800

850

Body W

eig

ht,

kg

Progeny RFI <= -0.44 Progeny RFI >= 0.44

W97

PC

W98

PC

PBPB

PB

PB

PB

PBPB

PC

PC

PC

PC

PC

PC

PC

W99W00

W01W02

W03

W04W05

W06

1997/98 1998/99 1999/00 2000/01 2001/02 2002/03 2003/04 2004/05 2005/06

PBPB1996/97

Long-term (1997-2006) body weight of cows that

produced -RFI and +RFI progeny

10 20 30 40 50 60 70

Cow age, mo

400

500

600

700

Bod

y w

eig

ht,

kg

+RFI -RFI

Relationship between RFIfat as a heifer and subsequent changes in body weight as a cow

PB1

MayPC1

Aug

PreCalf-1

Feb

PB2

May

PC2

Oct

PreCalf-2

Mar

PB3

May

PC3

Oct

begin swath grazing

at ~3.5-yr old

reduces winter feeding costs by 47%

Swath Grazing

10 20 30 40 50 60 70

Cow age, mo

400

500

600

700

Bod

y w

eig

ht,

kg

+RFI -RFI

Relationship between RFIfat as a heifer and subsequent changes in body weight as a cow

PB1

MayPC1

Aug

PreCalf-1

Feb

PB2

May

PC2

Oct

PreCalf-2

Mar

PB3

May

PC3

Oct

PreCalf-3

Mar

PB4

May

PC4

Oct

PreCalf-4

Mar

PC5

Oct

backfat, 4.5 vs. 7.4 at 59 mo

backfat, 10.0 vs. 12.0 at 68 mo

begin swath grazing

at ~3.5-yr old

Repeatability of RFI in heifers to cows

Peter Lawrence, 2012, University College Dublin, Ireland

RFI measured as a heifer

Traits High Med Low sign.

DMI, kg/day

12 mo of age 6.66a 6.07b 5.60c ***

24 mo of age 8.62a 8.12ab 7.68b *

36 mo of age 9.66 8.95 8.96 NS

RFI computed on post-weaned heifers offered grass silage ad libitum and

2 kg concentrate/hd/day, and grass silage ad libitum during 1st and 2nd parity

Feed savings:1 kg DM/cow/d x $0.15/kg DM x 365 = $55/cow/yr

Selection for low RFI-fat will:

Have no effect on growth, body size or

slaughter weight

Reduce feed intake at equal weight and ADG

Improve feed to gain ratio by 10-15%

Reduce net energy required for maintenance

Reduce methane production by 20-30%

Have no effect on carcass yield & quality grade

Little if any effect on age at puberty

No effect on calving pattern in first calf heifers

No negative effect on pregnancy, calving or weaning rate

Positive effect on body fatness/weight particularly during

stressful periods

Reduce feed costs - $0.05-0.10/hd/d feeders, $19-38 mil.

- $0.08-0.15/hd/d in cows; $54-110 mil.

Effect on feed intake on pasture??

Selection for low RFI-fat will:

Multi-trait Selection indices

Feedlot profitability Index (FPI): Increase genetic potential of market progeny for feedlot profit

(Crews et al. 2003)

FPI = 7.43 EBVRFI-fat + 37.38 EBVADG + -0.12 EBVWT365

RFI-fat =bull’s RFI adjusted for final off-test ultrasound

backfat thickness, kg DMI/day

ADG = bull’s post-weaning average daily gain, kg/day

WT365 = bull’s 365-day weight, kg

Also consider carcass grade fat thickness, ribeye area and marbling

Multi-trait Selection indices

Maternal Productivity Index (MPI): consistently wean heavy calves over a sustained herd life, while

controlling cow feed costs (Mwansa et al. 2002).

MPI = $3.00 EBVWWTd + $2.70 EBVWWTm – $0.49 EBVCOWT + $2.39 EBVSURV3

WWTd = direct weaning weight (30%)

WWTm = maternal weaning weight (26%)

COWT = cow weight (17%)

SURV3 = ability of a female to produce at least 3 calves given she

became a dam (27%)

Also consider heifer/bull RFI-fat adjusted, age at first calving, calving ease

and birth weight

Others (e.g. protein turnover, ion

pumping, protein leakage, thermoregulation,

stress (60%)

Feeding Patterns (2%)

Body composition (5%)

Heat Increment (9%)

Digestion (14%)

Activity (10%) Richardson and Herd, 2004

Herd et al., 2004

Biological Mechanisms Contributing to Variation in RFI

RFI, kg DM/day 1.25 -1.18 <0.001

Metabolic BW 89.0 93.8 0.48

ADG, kg/day 1.46 1.48 0.39

DMI, kg/day 11.62 9.62 0.01 17.2%

Fecal DM, g/kg DMI 272 234 0.24

Urine, g/kg MWT 56.3 45.5 0.25

Urine N, g/kg DMI 8.60 7.13 0.19

CH4, L/day 152.2 120.1 0.04 21.1%

CH4, % of GEI 4.28 3.19 0.04 25.5%

HIGH LOW

RFI RFI

Sign.

level Trait

Relationship of feedlot RFI with fecal DM, urine

and methane production in steers fed at 2.5x NEm.

LOW RFI: ME higher, HP lower, RE higher (kcal/kg MWT)

Feed intake tests favor later maturing heifers and bulls

-1.25 kg DM/d

individual

0.0 kg DM/d

contemporary group average

RFI h2

Estimated Breeding value A Simple Example

0.40

Bull RFI-p EBV = -1.25 kg DM/day x 0.40 = -0.5 kg DM/day

Cow RFI-p EBV = 0.00 kg DM/day X 0.40 = 0.0 kg DM/day

Expected Progeny Difference =

(-0.5 +0.0)/0.5 = -0.25 kg DM/day

Accuracy=40%

-1.5 -1 -0.5 0 0.5 1 1.5

RFI-fat, kg DM/day

0

50

100

150

200

250

300

350

Pr

od

uc

tiv

ity

, kg

we

an

ed

/ma

tin

g o

pp

or

tun

ity

Relationship between heifer post-weaning RFIfat and their

subsequent lifetime productivity

190.8 kg calf weaned/

mating opportunity

222 mating opportunities

86 heifers

191.8 kg calf weaned/

mating opportunity

224 mating opportunities

83 heifers

No difference in calf birth weight, pre-weaning ADG and weaning weight

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