Maternal Productivity

Project

(southern Aust)

Jeisane Accioly, Fiona Jones and

Michael Laurence(on behalf of a large team)

WA Maternal Productivity WA Maternal Productivity TeamTeam

Brad Seib

John Milligan

Tex Hann

NolaMercer

Ryan Drage

Brian McIntyre Peter Jelinek LeonardaPaszkudzka-Baizert

Greg Sawyer

CollaboratorsCollaborators

Western Australia

• Jane Speijers

Other Researchers

South Australia

• Wayne Pitchford

• Katrina Copping

• Mick Deland

• Nick Edwards

• Ian Carmichael

• Michelle Hebart

• Stephen Lee

New South Wales

• Kath Donehue

•Robert Herd

• Peter Parnell

Victoria

• John

Graham

Industry Push

Low Efficiency High Efficiency

1. Adoption of selection

strategies influencing

body composition (e.g.

RBY and NFI) constrained

by industry concerns

about impact on breeding

herd efficiency, especially

in variable nutritional

environments

Key industry issuesKey industry issues

2. The seedstock industry

lacks suitable selection

criteria for effective

improvement of

breeding herd efficiency

(kg cow and calf per MJ

energy consumed by

cow & calf)

Key industry issuesKey industry issues

Key issue in SouthKey issue in South

Maternal efficiency:

Cow feed (75%)

• Maintenance

• Energy storage & retrieval

Reproductive performance

Calving ease

Calf value

Longevity

Cow salvage value

Improve breeding herd efficiency in temperate Australia

Impact of selection for body composition on herd efficiency,

especially under variable nutrition

Efficient use of available feed resources & body reserves to

produce progeny

Full multi-trait index with measure of maternal efficiency &

optimally weighted composition traits for variable environments

Project aimsProject aims

Key research question …

Does selection for improved NFI or RBY% influence breeding herd efficiency* ?

Hypothesis: Selection for reduced NFI and reduced carcass fatness increase

breeding herd efficiency in good, but not in poor

nutritional environments

* Kg of cow and calf liveweight / MJ energy

consumed by the breeding herd

Two approaches:

1. Correlations between traits across large range of production

systems (Industry herds)

2. Differences between divergent single-trait lines in formal

design (Research herds)

Project approachProject approach

Animal Selection• 154 “fat line” yearling heifers arrived Jan-Feb 07

sourced from industry seedstock herds in Vic & SA

(‘B’ heifers).

• 62 NFI heifers arrived Jan-Feb 08 Sourced from Trangie NFI Selection Herd, NSW.

• 95 “fat line” yearling heifers arrived Feb-Mar 08 sourced from industry seedstock herds in Vic & SA (‘C’ heifers).

Maternal efficiency herds

Angus

Hereford

Research herds

Vasse (WA)

Struan (SA)

4 LinesHigh FatLow FatLow FatHigh NFILow NFI

2 NutritionHighLow

2 SitesVasse, WAStruan, SA

x x

Intensive measurements and estimation of food intake

Research herdsResearch herds

3 calving seasons

EBV differences EBV differences between the linesbetween the lines

EBVHigh Fat (n=170)

Low Fat (n=170)

High NFI (n=81)

Low NFI (n=81)

Rib fat 1.2 -1.4 3.2 -0.4

Rump P8 1.4 -1.5 3.0 -0.6

NFIP 0.65 -0.47

NFIF 0.77 -0.87

BWt 3.8 4.9 2.9 4.6

Wt200 31.3 36.3 18.9 25.9

Milk 10.8 10.6 7.8 9.0

Wt600 75.9 83.8 47.6 60.6

MCWT 67.7 81.3 42.0 58.6

DTC -3.3 -1.8 -1.2 0.3

EMA 2.40 2.10 0.42 0.48

Heifer managementHeifer management

Nutritional treat’s applied

9 week joining

Calving

SepSep

OctOct

NovNov

Dec Dec

JanJan

FebFeb

MarMar

AprApr

MayMay

JuneJune

JulyJuly

AugAug

SepSep

OctOct

NovNov

Dec Dec

JanJan

FebFeb

JuneJune

JulyJuly

AugAug

Sep Sep

OctOct

NovNov

Dec Dec

JanJan

FebFeb

MarMar

AprApr

MayMay

JuneJune

JulyJuly

AugAug

SepSep

OctOct

NovNov

9 week joining

Nutritional treat’s applied

Calving

Weaning Weaning

VasseVasse StruanStruan

9 week joining9 week joining

0

100

200

300

400

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Pas

ture

En

erg

y S

up

ply

(M

J/h

a/d

ay)

0.0

100.0

200.0

300.0

400.0

Cat

tle

En

erg

y D

eman

d

(MJ/

hea

d/d

ay)

Energy Supply & Demand: Early Calvers & Late CalversEnergy Supply & Demand: Early Calvers & Late Calvers

Rainfall (mm)

2006: 577 mm 2007: 810 mm 2008: 671 mm 2009: 679 mm2010: 464.1mm

0

50

100

150

200

250

300

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2006 20072008 20092010

Nutritional controlNutritional control

Fat lines

Weight of Fat cowsWeight of Fat cows

0

100

200

300

400

500

600

700

PM1 W0 PM 2 W1

Co

w W

eig

ht

(kg

)

High Fat Low Fat High Fat High Nut Low Fat High Nut High Fat Low Nut Low Fat Low Nut

P8 FatP8 Fat

0

2

4

6

8

10

12

PM1 W0 PM 2 W1

Co

w p

8 F

at (

mm

)

High Fat Low Fat High NFI High Nut Low NFI High Nut High NFI Low Nut Low NFI Low Nut

11stst calvers pre-mating calvers pre-mating and pregnancy testand pregnancy test

LineAge

(days)*Weight

(kg)P8 fat

(mm)***Conception

rate*

Adjusted conception

rate*

High Fat 473 370 6.5 93.5 93.4

Low Fat 465 367 4.9 85.1 86.8

Pre-mating and pregnancy Pre-mating and pregnancy test 2test 2ndnd calving calving

Line NutritionWeight (kg)***

P8 fat (mm)**

Conception rate

High Fat High 531 8.3 94.9

High Fat Low 488 5.4 88.4

Low Fat High 575 7.6 93.5

Low Fat Low 491 4.2 85.7

Days to calving for Days to calving for heifersheifers

260

270

280

290

300

310

320

330

High Nutrition Low Nutrition

Day

s To

Cal

ving

(day

s)

High Fat Low Fat

*

Days to Calving 2Days to Calving 2ndnd calvers calvers

295

297

299

301

303

305

307

309

311

313 High Fat - High Nut" High Fat - Low Nut

Low Fat- High Nut Low Fat - Low Nut

MessagesMessages

• Low fat cows were bigger / heavier (ave. 50kg)

• Low fat cows were leaner (>3mm)

• Fat difference was consistent across seasons

• Low fat cows seem to have poorer reproduction??

Birth weightBirth weight

0

5

10

15

20

25

30

35

40

1st calf 2nd calf

Bir

th W

eig

ht

(kg

)

High Fat High Nut Low Fat High Nut High Fat Low Nut Low Fat Low Nut

Calf weaning weight Calf weaning weight from 1from 1stst calvers calvers

Messages (calves)Messages (calves)

• No effect of fat genotype on birth or weaning weight

• Nutrition effect on weaning weight

Net Feed

Intake lines

Weight of NFI cowsWeight of NFI cows

P8 Fat – NFI cowsP8 Fat – NFI cows

0

2

4

6

8

10

12

14

16

PM1 W0 PM 2 W1

Co

w p

8 (m

m)

High NFI Low NFI High NFI High Nut Low NFI High Nut High NFI Low Nut Low NFI Low Nut

11stst calvers pre-mating calvers pre-mating and pregnancy testand pregnancy test

LineAge

(days)Weight

(kg)P8 fat

(mm)***Conception

rate

Adjusted conception

rate

High NFI 493 306 10.4 91.9 91.8

Low NFI 492 315 8.2 91.6 91.6

Pre-mating and pregnancy Pre-mating and pregnancy test 2test 2ndnd calving calving

Line NutritionWeight

(kg)P8 fat

(mm)***Conception

rate

High NFI High 478 11.9 95.1

High NFI Low 441 8.7 96.1

Low NFI High 488 8.8 87.4

Low NFI Low 438 6.1 88.7

Days to calving for Days to calving for heifersheifers

260

270

280

290

300

310

320

330

High Nutrition Low Nutrition

Day

s To

Cal

ving

(day

s)

High NFI Low NFI

Days to Calving 2Days to Calving 2ndnd calvers calvers

310

312

314

316

318

320

322

324

326

High NFI High Nut High NFI Low Nut Low NFI High Nut Low NFI Low Nut

Birth weightBirth weight

0

5

10

15

20

25

30

35

40

1st calf 2nd calf

Bir

th W

eig

ht

(kg

)

High NFI High Nut Low NFI High Nut High NFI Low Nut Low NFI Low Nut

Calf weaning weight Calf weaning weight from 1from 1stst calvers calvers

MessagesMessages

• No difference in weight of cows

• Trend for Low NFI cows to be leaner

• No effect of NFI in reproduction

• No effect of NFI in birth or weaning weight

• Effect of nutrition on

weaning weight

Main messagesMain messages

• Genetically fatter cows seem to be more fertile, especially under low nutrition

• Selection for body composition holds across seasons and nutrition treatments

• No effect of cow fatness or NFI EBV on weaning weight of her calf

• Selection for NFI is associated with changes in fatness

To be continued …