Loading…

Flash Player 9 (or above) is needed to view presentations.
We have detected that you do not have it on your computer. To install it, go here.

Like this presentation? Why not share!

Vasse presentation stephen lee

on

  • 392 views

 

Statistics

Views

Total Views
392
Views on SlideShare
392
Embed Views
0

Actions

Likes
0
Downloads
4
Comments
0

0 Embeds 0

No embeds

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

    Vasse presentation stephen lee Vasse presentation stephen lee Presentation Transcript

    • Reporting outcomes from social science and industry herd data analysis
      Stephen Lee
      Ian Nuberg
      Wayne Pitchford
    • Maternal Productivity
      Difficult to define:
      • the outputs in the beef production system relative to the inputs
      • weight of calf weaned / MJ energy cow calf unit
      • cow weight change (kg)
      Traits include:
      Reproductive performance (no. of calves weaned per cow exposed)
      Pre-weaning growth of progeny
      Change in size and body composition of the cow
      Motivating concern
      • How does increasing production potential impact on breeding herd efficiency?
    • Research Approach
      In-depth interviews with seedstock breeders on role and key influencers of maternal productivity
      • hypotheses generating – logic of breeding and management
      Maternal Productivity Data from 4500 industry animals over first and second parity
      associations between performance potential (EBVs) and body energy reserves
      genetic parameter estimates
      reproduction differences
      output traits (calf weaning weight, cow weight change)
      Management and breeding implications for cows differing in genetic potential
    • Breeding goals
      Majority of breeders had similar goals:
      low cost of production
      high quality product (marbling and yield)
      multiple end market specifications
      structural soundness
      temperament
      Contrasting on-farm animal management approach
    • Diverse management
    • Controlled input
      ‘I have a real problem with fat and I touched on this before in regard to cow condition. Fat is expensive to put on, you put it on, the animal goes to the processor and they cut if all off. When you feed it (fat) on and it costs you somewhere in the vicinity of 40% of every mega-joule you end up using in the process of putting it on and then re-metabolising it again, that’s just crazy’
      ‘If you couldn’t do it any other way and we were dropping 10% conception rate, then you have to have that fat there. If you can have yield and have efficient cows, then to me the wrong thing for a seedstock business to do is to push positive fat.’
    • Variable input
      ‘We have done a study of what it costs us to produce dry matter during the year and it is about 4 times as cheap during spring compared to autumn. So that says a lot about when you put condition on and when you can let the cows coast through. The ones that have stayed in the system have this ability where they can put weight on quickly in spring when there is compensatory growth and they can draw down on those reserves when things are tougher and then gain weight quickly when the feed is available.’
      ‘I use the carcass traits more for maternal productivity than for carcass. It is huge, rib and rump, whenever I use an AI sire I have a really good look at his fat EBVs. When I use a negative fat bull the drop out rate in our maternal side is too high.’ ‘I know the feedlot buyer wants high yielding steers but I can’t afford that in the cow herd.’
    • Maternal Productivity
      Calving ease
      Calf growth
      Feed Intake (energy)
      Fertility – 365 day breeding cycle
      Pre-calving energy reserves
      P8 and Rib EBVs
      EMA EBV
      600d Wt EBV
      Milk EBV
      Frame
      Maturity pattern
    • EBV Standard Deviations
    • 962 progeny
      77 herds
      623 progeny
      in 20 herds
    • Percentage increase in P8 fat depth for 1mm increase in P8 EBV
      %change in P8 fat depth
      A 1mm increase in P8 fat EBV for Angus at pre-calving first parity (PC1) increased scanned P8 fat depth by 14.6%
    • Maternal Productivity
      Calving ease
      Calf growth
      Feed Intake (energy)
      Fertility – 365 day breeding cycle
      Pre-calving energy reserves
      P8 and Rib EBVs
      EMA EBV
      600d Wt EBV
      Milk EBV
      Frame
      Maturity pattern
    • Relationship between Rib and P8
      EBVs and observed days to calving
      A 1mm increase in P8 EBV resulted in reduced observed DTC by 0.95 days in Spring and 2.45 days in Autumn
    • Relationship between pre-calving rib fat depth and observed days to calving
      In Spring calving cows for every extra millimetre pre-calving scan rib fat depth, observed days to calving was reduced by 0.39 days, this effect was larger in Autumn calving cows (-2.89).
    • Summary
      Cow management approach differed between breeders (CONTROL vs. VARIABLE)
      Cow management approach was linked with attitude to optimal EBVs for traits including fat, growth and milk
      Body composition
      • EBVs for P8 and Rib impact cow fat depth at pre-calving and weaning (approx 15% per standard deviation)
      • Body composition traits are phenotypically repeatable for pre-calving and weaning
    • Summary
      Days to calving and Rib and P8 EBVs
      Approx 1.0 days shorter DTC in spring
      Approx 2.5-2.9 days shorter DTC in autumn
      Pre-calving but not weaning cow fat depth impacts subsequent days to calving
      Approx 2.89 days/mm rib fat in autumn and
      Approx 0.39 days/mm rib fat in spring.
      • For control input management, where it is cost effective to increase inputs (feed), the effect of increasing genetic potential for yield (leanness) is unlikely to compromise observed pre-calving energy reserves
      • However, in variable input systems, the ability for young cows with high potential for leanness and growth to attain sufficient pre-calving energy reserves in adverse seasons may be compromised
    • Acknowledgements
      Ian Nuberg
      Wayne Pitchford
      Angus Australia
      Herefords Australia
      Collaborating herds!