EBVs and the breeding herd –

What’s happening out

there?

Wayne Pitchford

Kath Donoghue

Genetic change in growth traits

50kg

Genetic change in body composition

Genetic change in profit per cow

Changing Genetic Potential

962 progeny analysed across 77 herds

623 progeny analysed across 20 herds

Sire 600d Wt (kg)

MCWt (kg)

Milk(kg)

DC(days)

Rib Fat

(mm)

Rump Fat

(mm)

RBY(%)

IMF%

Long Fed

Index ($)

1 +122 +119 +20 -8.7 -3.2 -3.2 +1.6 +0.6 +103

2 +57 +50 0 -4.7 +4.5 +3.6 -2.0 +3.7 +98

Data collection

Traits:

– Weight and Height

– P8 and Rib fat and IMF%

– Eye muscle area and Condition Score

Time of collection:

– 1st parity: Pre Calving (PC1) and Weaning (W1)

– 2nd parity: Pre Calving (PC2) and Weaning (W2)

Industry herds:Bald Blair Angus Barwidgee AngusBooroomooka Angus Chis AngusEastern Plains Angus Kenny’s Creek AngusRennylea Angus South Boorook HerefordsTe Mania Angus Tuwhareto AngusTwynam Angus Willalooka AngusWirruna Herefords Yalgoo HerefordsYavenvale Herefords

Ultrasound technicians:Jim GreenLiam CardileMatt Wolcott

Acknowledgements

Data structure

Angus (n=5,949) Hereford (n=1,452)

PC1 4,867 1,124

W1 3,735 645

PC2 2,772 918

W2 2,109 485

Average (SD) 2p (SE) h2 (SE)

A H A H A H

n=3,735 n=645

WT (kg) 515 (64) 503 (43) 2,003 (58) 1,868 (114) 0.39 (0.05) 0.42 (0.12)

P8 (mm) 5.8 (2.9) 6.8 (3.0) 5.4 (0.17) 17 (13) 0.51 (0.06) 0.97 (0.06)

Rib (mm) 5.0 (2.2) 5.0 (1.8) 3.2 (0.10) 3.3 (0.21) 0.49 (0.05) 0.54 (0.14)

EMA (cm2) 59 (9) 58 (6) 42 (1.2) 40 (2.4) 0.32 (0.05) 0.47 (0.11)

IMF (%) 5.5 (1.9) 2.9 (0.08) 0.39 (0.05)

Descriptive statistics – W1

Phenotypic relationships for same trait over time

Trait PC1-W1 W1-PC2 PC2-W2

WT 0.66 (0.01) 0.79 (0.009) 0.72 (0.01)

P8 0.47 (0.02) 0.74 (0.01) 0.57 (0.02)

Rib 0.49 (0.02) 0.72 (0.01) 0.57 (0.02)

EMA 0.45 (0.02) 0.63 (0.02) 0.50 (0.02)

IMF 0.51 (0.01) 0.69 (0.01) 0.54 (0.02)

Trait PC1-W1 W1-PC2 PC2-W2

WT 0.88 (0.03) 0.94 (0.03) 0.95 (0.02)

P8 0.70 (0.05) 0.89 (0.04) 0.92 (0.04)

Rib 0.65 (0.05) 0.96 (0.04) 0.96 (0.03)

EMA 0.68 (0.07) 0.84 (0.06) 0.85 (0.07)

IMF 0.76 (0.06) 0.92 (0.04) 0.86 (0.06)

Genetic relationships for same trait over time

Change in weight: 1st lactation (n=3,615)

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Change in WT, kg

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Change in P8 (mm)

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Change in P8: 1st lactation (n=3,616)

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Change in EMA, sq.cm

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Change in EMA: 1st lactation (n=3,623)

Change in Weight over time

Trait 1st lactationWeaning –

Calving2nd lactation

1st lactation 0.16 (0.04) -0.53 (0.02) 0.10 (0.03)

Weaning –

Calving-0.51 (0.23) 0.09 (0.04) -0.43 (0.03)

2nd lactation 0.62 (0.20) -0.30 (0.27) 0.14 (0.05)

rp above; rg below

Change in traits: 1st lactation

Trait WT P8 EMA IMF

WT 0.48 (0.01) 0.43 (0.01) 0.36 (0.02)

P8 0.70 (0.10) 0.39 (0.02) 0.40 (0.02)

EMA 0.70 (0.12) 0.68 (0.11) 0.35 (0.02)

IMF 0.71 (0.12) 0.76 (0.10) 0.74 (0.11)

rp above; rg below

Messages

Currently rapid change in cattle growth, carcass

composition and profit. Will accelerate!

Cow weight and body composition is heritable and

repeatable over time

Cows change in weight and composition substantially

throughout year

Change in weight is lowly heritable

Thank you for the

enormous contribution from the Vasse team

and for listening!

Contemporary groups

Number Avg size Min size Max size

PC1 188 57 2 182

PC2 86 87 2 171

Pre-Calving:• Preg status• Parity 1 wean status (PC2 only)• Season (Autumn, Spring)• Herd• Breeder management group

Number Avg size Min size Max size

W1 117 110 2 368

W2 87 70 2 161

Weaning:• Preg status of current parity• Preg status of future parity• Wean status of current parity• Season (Autumn, Spring)• Herd• Breeder management group

Contemporary groups

Model of analysis

Animal model fitted using ASReml: Contemporary group Age of animal Direct genetic effect

Bivariate analyses: Same trait across 4 time points (PC1, W1, PC2,

W2) Different traits within same time point

Contemporary groups

Number Avg size Min size Max size

PC1 188 57 2 182

PC2 86 87 2 171

Pre-Calving:• Preg status• Parity 1 wean status (PC2 only)• Season (Autumn, Spring)• Herd• Breeder management group

Number Avg size Min size Max size

W1 117 110 2 368

W2 87 70 2 161

Weaning:• Preg status of current parity• Preg status of future parity• Wean status of current parity• Season (Autumn, Spring)• Herd• Breeder management group

Contemporary groups

Model of analysis

Animal model fitted using ASReml: Contemporary group Age of animal Direct genetic effect

Bivariate analyses: Same trait across 4 time points (PC1, W1, PC2,

W2) Different traits within same time point

Descriptive statistics – PC1

Average (SD) 2p (SE) h2 (SE)

A H A H A H

n=4,867 n=1,124

WT (kg) 487 (70) 456 (33) 1,209 (33) 1,083 (50) 0.55 (0.05) 0.46 (0.08)

P8 (mm) 5.8 (3.1) 6.4 (2.4) 4.2 (0.11) 6.0 (0.30) 0.52 (0.05) 0.56 (0.09)

Rib (mm) 4.6 (2.2) 4.4 (1.4) 2.1 (0.06) 2.1 (0.10) 0.50 (0.05) 0.65 (0.08)

EMA (cm2) 57 (10) 50 (6) 36 (0.86) 39 (1.7) 0.30 (0.04) 0.15 (0.06)

IMF (%) 5.2 (2.0) 2.3 (0.06) 0.34 (0.04)

Average (SD) 2p (SE) h2 (SE)

A H A H A H

n=2,772 n=918

WT (kg) 552 (73) 533 (41) 1,933 (63) 1,671 (80) 0.36 (0.06) 0.07 (0.07)

P8 (mm) 6.1 (3.2) 7.6 (3.0) 5.5 (0.18) 9.1 (0.45) 0.33 (0.06) 0.20 (0.08)

Rib (mm) 4.9 (2.4) 4.9 (1.7) 3.0 (0.10) 3.0 (0.14) 0.28 (0.06) 0.18 (0.08)

EMA (cm2) 61 (9.8) 55 (7) 45 (1.4) 47 (2.3) 0.25 (0.05) 0.25 (0.09)

IMF (%) 5.5 (2.2) 2.8 (0.09) 0.28 (0.06)

Descriptive statistics – PC2

Average (SD) 2p (SE) h2 (SE)

A H A H A H

n=2,109 n=485

WT (kg) 585 (74) 588 (49) 2,981 (119) 2,539 (173) 0.54 (0.07) 0.30 (0.14)

P8 (mm) 7.9 (4.1) 11 (4.8) 9.8 (0.42) 23 (1.6) 0.64 (0.08) 0.37 (0.17)

Rib (mm) 6.6 (3.1) 6.7 (2.6) 5.7 (0.24) 6.7 (0.44) 0.57 (0.08) 0.05 (0.11)

EMA (cm2) 63 (9.4) 62 (7) 42 (1.5) 48 (3.2) 0.23 (0.06) 0.14 (0.12)

IMF (%) 6.1 (1.8) 2.5 (0.09) 0.37 (0.07)

Descriptive statistics – W2

Trait WT-P8 WT-EMA WT-IMF P8-EMA P8-IMF EMA-IMF

PC1 0.18 (0.02)

0.41 (0.02)

0.20 (0.02)

0.30 (0.02)

0.42 (0.02)

0.32 (0.02)

W1 0.39 (0.02)

0.53 (0.01)

0.35 (0.02)

0.45 (0.02)

0.57 (0.01)

0.45 (0.02)

PC2 0.30 (0.02)

0.46 (0.02)

0.24 (0.02)

0.36 (0.02)

0.51 (0.02)

0.35 (0.02)

W2 0.39 (0.02)

0.49 (0.02)

0.29 (0.03)

0.47 (0.02)

0.49 (0.02)

0.39 (0.02)

Phenotypic relationships between traits

Trait WT-P8 WT-EMA WT-IMF P8-EMA P8-IMF EMA-IMF

PC1 0.09 (0.08)

0.48 (0.07)

0.21 (0.08)

0.28 (0.08)

0.42 (0.07)

0.31 (0.09)

W1 0.27 (0.09)

0.51 (0.08)

0.29 (0.10)

0.44 (0.08)

0.70 (0.06)

0.42 (0.09)

PC2 0.12 (0.13)

0.53 (0.10)

-0.04 (0.15)

0.13 (0.15)

0.47 (0.11)

0.21 (0.15)

W2 0.45 (0.09)

0.66 (0.09)

0.15 (0.13)

0.68 (0.09)

0.57 (0.09)

0.37 (0.15)

Genetic relationships between traits

Moderate, consistent phenotypic relationships

Mostly consistent genetic relationships

WT higher rg with EMA than fat

Fat traits (P8, Rib, IMF) appear highly correlated

Reanalyse when data collection complete

Messages

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Change in weight: Between parities (n=1,614)

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Change in weight: Parity 2 (n=2,062)

Trait Parity 1 Between parities Parity 2

Parity 1 0.30 (0.05) -0.44 (0.02) 0.11 (0.03)

Between parities -0.72 (0.13) 0.16 (0.05) -0.46 (0.02)

Parity 2 0.97 (0.10) -0.67 (0.18) 0.26 (0.06)

rp above; rg below

Change in P8 over time

Trait Parity 1 Between parities Parity 2

Parity 1 0.16 (0.04) -0.46 (0.02) 0.04 (0.03)

Between parities -0.85 (0.13) 0.11 (0.04) -0.52 (0.02)

Parity 2 0.34 (0.30) -0.72 (0.23) 0.06 (0.03)

rp above; rg below

Change in EMA over time

Trait Parity 1Between parities

Parity 2

Parity 1 0.17 (0.04) -0.39 (0.02) 0.09 (0.03)

Between parities -0.51 (0.23) 0.10 (0.05) -0.52 (0.02)

Parity 2 0.63 (0.23) -0.73 (0.28) 0.10 (0.04)

rp above; rg below

Change in IMF over time

Messages

Other composition traits have similar trends to WT

Do we need to scan cows?

Seedstock sector – selection for adaptation

Breeder sector – monitoring condition/adaptation

Reanalyse when data collection complete

Trait WT P8 EMA IMF

WT 0.34 (0.02) 0.31 (0.02) 0.26 (0.02)

P8 0.57 (0.20) 0.32 (0.02) 0.28 (0.02)

EMA 0.84 (0.17) 0.79 (0.24) 0.29 (0.02)

IMF 0.79 (0.18) 0.51 (0.24) 0.62 (0.29)

rp above; rg below

Change in traits: Parity 2

Trait WT P8 EMA IMF

WT 0.20 (0.03) 0.23 (0.02) 0.18 (0.03)

P8 0.29 (0.28) 0.15 (0.03) 0.26 (0.03)

EMA 0.79 (0.19) -0.13 (0.30) 0.24 (0.02)

IMF 0.49 (0.36) 0.42 (0.31) 0.70 (0.20)

rp above; rg below

Change in traits: Between parities

Messages

Phenotypic correlations still moderate

Most genetic correlations lower than Parity 1 & 2

May need to scan cows?

High SE on all rg

Reanalyse when data collection complete

All traits are moderately heritable

EMA & IMF similar to published estimates in

yearling heifers

P8 & Rib higher than published estimates- stage

of physiology??

WT similar to Angus MCW (0.41)

Reanalyse when data collection complete

Messages

Messages

Phenotypic correlations moderate to high

Genetic correlations high to very high

May not need repeated measures on cows

PC1-W1 phenotypic & genetic correlations lowest

Only first 2 parities measured

Need to compare to young measures

Reanalyse when data collection complete

Low h2 for change in weight

Change in parity 1 reasonable indicator of change in

parity 2, genetically (rg = 0.62)

But rp is 0 so environmental correlation must be

negative???

Change in parity 1 is in opposite direction to change

between parities, (rg = -0.51, rp = -0.53 )

Messages

Messages

Genetically – all traits changing in same direction

Phenotypic is more moderate

Do we need to scan cows?

Seedstock sector – selection for adaptation

Breeder sector – monitoring condition/adaptation

Change in body composition and maternal output

Trait change:

Have to be in same CG at both time points

Age at first time point

Direct genetic effect

Maternal output (Calf weaning weight):

Unadjusted calf WWT

CG: CG of dam for trait change PRELIMINARY ANALYSIS!

Trait change & maternal output: Parity 1

Calf WWT (h2 =0.12)

Phenotypic correlation Genetic correlation

WT -0.13 (0.02) -0.24 (0.20)

P8 -0.12 (0.02) -0.31 (0.18)

Rib -0.11 (0.02) -0.26 (0.17)

EMA -0.12 (0.02) -0.50 (0.19)

IMF -0.14 (0.02) -0.51 (0.18)

Calf WWT (h2 =0.17)

Trait Phenotypic correlation Genetic correlation

WT -0.15 (0.02) -0.54 (0.19)

P8 0.04 (0.02) -0.10 (0.25)

Rib 0.02 (0.02) -0.10 (0.26)

EMA 0.04 (0.02) -0.47 (0.28)

IMF -0.05 (0.02) -0.67 (0.23)

Trait change & maternal output: Parity 2

Messages

Increased calf WWT moderately associated genetically

with loss of condition in cows

Low to zero phenotypic correlations

h2 of calf WWT low, but is maternal genetic component (1/4

Vdir + Vmat)

High SE on all rg

Make further refinements to model

Reanalyse when data collection complete

Future analyses

Yearling measures with later life traits

Fertility analyses

Lifetime maternal productivity