2. WA Maternal ProductivityWA Maternal Productivity
TeamTeam
Brad
Seib
John
Milligan
Tex
Hann
Nola
Mercer
Ryan Drage
Brian McIntyre Peter Jelinek
Leonarda
Paszkudzka-Baizert
Greg Sawyer
4. 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
6. 386 kg Start wt 398 kg
1.5 kg/d ADG 1.5 kg/d
1640 kg Expected feed 1670 kg
1880 kg Actual feed 1580 kg
+ 240 kg Net feed intake - 90 kg
Low Efficiency High Efficiency
7. 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 issues
8. 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 issues
9. Key issue in South
Maternal efficiency:
Cow feed (75%)
• Maintenance
• Energy storage & retrieval
Reproductive performance
Calving ease
Calf value
Longevity
Cow salvage value
10. 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 aims
11. 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
12. 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 approach
13. 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
15. 4 Lines
High Fat
Low FatLow Fat
High NFI
Low NFI
2 Nutrition
High
Low
2 Sites
Vasse, WA
Struan, SA
x x
Intensive measurements and estimation of food intake
Research herds
3 calving seasons
18. 0
100
200
300
400
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
PastureEnergySupply
(MJ/ha/day)
0.0
100.0
200.0
300.0
400.0
CattleEnergyDemand
(MJ/head/day)
Energy Supply & Demand: Early Calvers & Late CalversEnergy Supply & Demand: Early Calvers & Late Calvers
19. Rainfall (mm)
2006: 577 mm 2007: 810 mm 2008: 671 mm 2009: 679 mm
2010: 464.1mm
0
50
100
150
200
250
300
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
2006 2007
2008 2009
2010
22. Weight of Fat cowsWeight of Fat cows
0
100
200
300
400
500
600
700
PM1 W0 PM 2 W1
CowWeight(kg)
High Fat Low Fat High Fat High Nut Low Fat High Nut High Fat Low Nut Low Fat Low Nut
23. P8 FatP8 Fat
0
2
4
6
8
10
12
PM1 W0 PM 2 W1
Cowp8Fat(mm)
High Fat Low Fat High NFI High Nut Low NFI High Nut High NFI Low Nut Low NFI Low Nut
24. 11stst
calvers pre-matingcalvers pre-mating
and pregnancy testand pregnancy test
Line
Age
(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
25. Pre-mating and pregnancyPre-mating and pregnancy
test 2test 2ndnd
calvingcalving
Line Nutrition
Weight
(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
26. Days to calving forDays to calving for
heifersheifers
260
270
280
290
300
310
320
330
High Nutrition Low Nutrition
DaysToCalving(days)
High Fat Low Fat
*
27. Days to Calving 2Days to Calving 2ndnd
calverscalvers
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
28. 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??
34. P8 Fat – NFI cowsP8 Fat – NFI cows
0
2
4
6
8
10
12
14
16
PM1 W0 PM 2 W1
Cowp8(mm)
High NFI Low NFI High NFI High Nut Low NFI High Nut High NFI Low Nut Low NFI Low Nut
35. 11stst
calvers pre-matingcalvers pre-mating
and pregnancy testand pregnancy test
Line
Age
(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
36. Pre-mating and pregnancyPre-mating and pregnancy
test 2test 2ndnd
calvingcalving
Line Nutrition
Weight
(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
37. Days to calving forDays to calving for
heifersheifers
260
270
280
290
300
310
320
330
High Nutrition Low Nutrition
DaysToCalving(days)
High NFI Low NFI
38. Days to Calving 2Days to Calving 2ndnd
calverscalvers
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
41. 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
42. 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