Interbull Routine Genetic Evaluation for Dairy Production Traits

December 2012


Introduction
The latest international evaluation for dairy production traits took place as scheduled at the Interbull Centre. Data from twenty seven (32) countries were included in this evaluation.

International genetic evaluations for milk, fat and protein yields of bulls from Australia, Austria-Germany, Belgium, Canada, Czech Republic, Denmark-Finland-Sweden, Estonia, France, Hungary, Ireland, Israel, Italy, Japan, Latvia,Lithuania, Netherlands, New Zealand, Norway, Poland, Republic of South Africa, Slovak Republic, Slovenia, Spain, Switzerland, the United Kingdom, the United States of America ,Portugal,Korea,Argentina and Urugay were computed. Brown Swiss, Guernsey, Holstein, Jersey, Red Dairy Cattle and Simmental breed data were included in this evaluation.

Changes in national procedures

Changes in the national genetic evaluation of production traits are as
follows:

ZAF GUE Methodology changed from a test-day model where lactations were included as repeated measures, to a multi-trait model where lactations are treated as different traits.
 
ZAF RDC Methodology changed from treating different lactations as repeated measures, to treating them as different traits in our test-day model.
 
ARG HOL  Participating for the first time.
 
URY HOL Participating for the first time.
JPN HOL Included 4 generations pedigree for cows with own yield records intead of 2 generations.Changed unknown parents group definition.Changed publication criteria from "15 daughters passed 90 DIM" to "15 daughters passed 120 DIM" in at least 10 herds.Therefore, number of daughters, number of herds, and EDC decreased in some bulls. 
 
SVN HOL, BSW, SIM Made some changes in method of evaluation and change the base.

INTERBULL CHANGES COMPARED TO THE AUGUST ROUTINE RUN

Introduction of the Interbull IDEA pedigree database
The Interbull Centre has changed the database platform from IBIS to IDEA, as it was presented in Cork. 

The "Restricted Area" on our website will no longer gather you access to the database. Clicking on the "Restricted Area" will provide you a warning message and a link to the correct IDEA page, but we highly recommend to bookmark https://idea.interbull.org. The access to IDEA will be available again through the Interbull Centre webpage when the new webpage will be ready. The previous username and password are no longer active in IDEA. Access to IDEA is now based on individual log ins, if you wish for co-worker(s) to also get access to the database you should send an email to Valentina or Carl (carl.wasserman@slu.se) with the complete name and email address of your co-worker(s).

Conversion equations
The Interbull Centre was notified that Interbull conversion equations were not applicable for some country-breed-trait combinations in which published national evaluations are not in the same scale as the corresponding national EBVs included in MACE. As a result, it was decided to include a code in the parameter file indicating if the country-breed-trait combination submitted to Interbull is on the nationally published scale. The information about scale will be included in the file with conversion equations sent back to countries as e.g. "Non Applicable".

Publication of proofs of imported bulls without Interbull proof from country of first registration.
Currently, the publication rule is that a proof of an imported bull (type of proof 21) only gets published if his first country proof (type of proof 11 or type of proof 12) is included in the evaluation for the specific sub-trait. Not all countries do participate in the complete service portfolio, and therefore, if the country of first proof of a bull is not included in MACE  evaluations the importing country of this bull do not get an Interbull proof back even if national daughter based proof is submitted to Interbull. The reason of including this rule in the past was to account for selection. The imported bulls are included in MACE if they have at least 150 daughters (or 150 EDC) in 50 herds (HOL), 30 daughters (or 30 EDC) in 10 herds (GUE), or 80 daughters (or 80 EDC) in 20 herds (other breeds), but not published if first country of proof is missing. The issue was presented and discussed during the Interbull Meetings in Cork, 2012, and it was decided to relax the business rule on the requirement of first country proof. The distribution files will therefore include these bulls.


Data and method of analysis

Data were national genetic evaluations of AI sampled bulls with at least 10 daughters or 10 EDC (for clinical mastitis and maternal calving traits at least 50 daughters or 50 EDC, and for direct calving traits at least 50 calvings or 50 EDC) in at least 10 herds. Table 1 presents the amount of data included in this Interbull evaluation for all breeds.

National proofs were first de-regressed within country and then analysed jointly with a linear model including the effects of evaluation country, genetic group of bull and bull merit. Heritability estimates used in both the de-regression and international evaluation were as in each country's national evaluation.

Table 2 presents the date of evaluation as supplied by each country in the 01x-proof file.

Estimated genetic parameters and sire standard deviations are shown in APPENDIX I and the corresponding number of common bulls are listed in APPENDIX II.

Scientific literature
The international genetic evaluation procedure is based on international work described in the following scientific publications:

International genetic evaluation computation:

Schaeffer. 1994. J. Dairy Sci. 77:2671-2678
Klei, 1998. Interbull Bulletin 17:3-7

Verification and Genetic trend validation:

Klei et al., 2002. Interbull Bulletin 29:178-182.
Boichard et al., 1995. J. Dairy Sci. 78:431-437

Weighting factors:

Fikse and Banos, 2001. J. Dairy Sci. 84:1759-1767

De-regression:

Sigurdsson and G. Banos. 1995. Acta Agric. Scand. 45:207-219
Jairath et al. 1998. J. Dairy Sci. Vol. 81:550-562

Genetic parameter estimation:

Klei and Weigel, 1998, Interbull Bulletin 17:8-14
Sullivan, 1999. Interbull Bulletin 22:146-148

Post-processing of estimated genetic correlations:

Mark et al., 2003, Interbull Bulletin 30:126-135
Jorjani et al., 2003. J. Dairy Sci. 86:677-679
http://www.interbull.org/documents/genetic_correlation_estimation_procedure.pdf 

Time edits

Weigel and Banos. 1997. J. Dairy Sci. 80:3425-3430

International reliability estimation

Harris and Johnson. 1998. Interbull Bulletin 17:31-36

Next routine international evaluation
The next routine evaluation of Interbull for production, conformation, udder health, longevity, calving, female fertility and workability traits is scheduled for April 2013. Deadline for sending data to the Interbull Centre is Tuesday March 19, 2013, 17:00 CET; confidential distribution of results is targeted for Thursday April 4, 2013, with earliest possible official release of results on April 9, 2013. Please remark the three weeks turn around due to Easter. 

Next test international evaluation
The next test run for production, conformation, udder health, longevity, calving, female fertility and workability traits will take place in January 2013.

Countries planning to introduce changes in their national evaluation procedures and wishing to have them included in the routine Interbull evaluation, should have their data examined in this test run. New data and validation results should be sent to the Interbull Centre no later than January 15, 2013, 17:00 CET.

PUBLICATION OF INTERBULL ROUTINE RUN
Results were distributed by the Interbull Centre to designated representatives in each country. The international evaluation file comprised international proofs expressed on the base and unit of each country included in the analysis. Such records readily provide more information on bull performance in various countries, thereby minimising the need to resort to conversions.

At the same time, all recipients of Interbull results are expected to honour the agreed code of practice, decided by the Interbull Steering Committee, and only publish international evaluations on their own country scale. Evaluations expressed on another country scale are confidential and may only be used internally for research and review purposes.

All recipients are also expected to follow the agreed guidelines for advertising genetic merit. The guidelines has been distributed to all members and is available on the Interbull homepage (http://www.interbull.org) under "Public Area/Publications/Guidelines/Interbull Advertising Guidelines".