Minutes from Interbeef Technical Committee Meeting

Nantes, August 27, 2013
La Cité Nantes Events Centre

Participants

Brian Wickham (WG Chairman), Lubos Vostry, Pavel Bucek, Zdenka Vesela, Clara Diaz Martin, Eric Venot, Ross Evans, Thierry Pabiou, Anders Fogh, Mohammad Nilforooshan, João Dürr, Laurent Griffon, Peter Amer (observer), Mike Coffey, Norman Maiwashe, Ludmila Zavadilová (observer), Gerben de Jong (observer), Amandine Launay and Andrew Cromie.

1 & 2. Opening and adoption of agenda

The Interbeef Chairman, João Dürr, welcomed all the participants. The agenda was accepted with one addition: Mohammad Nilforooshan requested space to report on the impact of the agreed publication rules on the number of animals to be published.

ADOPTED AGENDA

Opening
Adoption of agenda
Minutes from meeting in Aarhus – May 27, 2012 (https://wiki.interbull.org/public/IBeef_Tech_Meet_Aarhus?action=print)__
Results from the survey on “Assessment of genetic parameter estimation procedures for weaning weight and inclusion of records from crossbred animals” (IRL)
Results from AWW variance components study (IRL)
September 2013 AWW routine run
1. Genetic parameters?
2. Inclusion of new countries in AWW evaluations
Preliminary results from the calving traits pilot run (CZE)
Technical Committee terms of reference
Other matters
Recommendations to the working group
Adjourn

3. Minutes from meeting in Aarhus

Eric Venot made the following remarks on the minutes:

What should be done about animals that change sex or breed from one evaluation to the next?
- Explanation: each authoritative organization is responsible for the quality of the information added to the Interbeef pedigree and changes made by the authoritative organization cannot be reverted by other users.
Should animals that are considered "invalid" by the authoritative organization be included in the evaluations?
- Recommendation: the Interbull Centre will investigate which animals are in such situation and the impact of removing these animals from the evaluation.

4. Results from the survey

Ross Evans presented the summary of the answers provided by the respondents. The survey provided a valuable description of the national procedures for variance component estimation, as well as the use of crossbred data. The presentation of the results are available at Survey_slides.pdf.

5. Results from AWW variance components study

Thierry Pabiou presented the results from the study on AWW LIM variance components carried out by the ICBF team. There was not enough time to finish the analyses for CHA before the meeting. The written report is available at INTERBEEF ACROSS COUNTRY VCE LIMOUSIN v5.pdf. The technical committee discussed the results and the main comments were:

Investigate if "invalid IDs" occur among common bulls
Pruning non-informative animals can reduce the number of equations substantially
Defining phantom groups should be considered
Prior to bending the matrix of correlations, add the weighted average of the correlations that converged in the empty cells instead of 0.80
Since there are so many non-estimable correlations, one possibility would be to consider all correlations as 1 (no genotype-environment interaction) for the time being and concentrate efforts on modelling the heterogeneous variance
It is probably best to consider the maternal effects as 1 because they are even more difficult to estimate than the direct genetic effects