Interbull Routine Genetic Evaluation for Calving Traits

April 2008

Introduction
International genetic evaluations for calving traits of bulls from Australia, Canada, Denmark, Finland, Sweden, France, Germany, Israel, Italy, The Netherlands, Norway, Switzerland, and The United States of America were included in this evaluation.

Changes in national procedures compared to the Interbull Routine Evaluation in January 2008;

• NLD changed limits for publication of calving trait proofs to a minimum of 35% for any calving trait. Earlier bulls could only get a BV for maternal traits if reliability was at least 35% for direct traits. Also, publication code is now set to Y when code 21 bulls have at least 15 daughters in 10 herds (was 75 and 50).
• AUS changed their expression of proofs to relative breeding values with a base of 100.
• ITA deleted two years of old data from their evaluation

Changes in Interbull procedures compared to the Interbull Routine Evaluation in May 2007;

• none.

Data and method of analysis

Data were national genetic evaluations of AI sampled bulls with at least 50 calves (direct effects) or calving daugthers (maternal effects) in at least 10 herds. Table 1, Table 2 and Table 3 present the amount of data included in this Interbull evaluation for Brown Swiss, Holstein, and Red Dairy Cattle, respectively.

Table 4 presents the date of evaluation as supplied by each country in the 018-proof file.

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 5).

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

Ancestor-bulls without own proofs were traced back two generations from the oldest bulls with proofs in order to increase across country connections and account for the effect of selection.

Genetic groups were defined according to unidentified parents by national origin, breed and birth year of the bull and path of selection (sire, maternal grand-sire, maternal grand-dam). Minimum group size was set to 30.

Publication of Interbull evaluations

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 "Publications and Documentation/General information".

Next routine international evaluation

The next routine international evaluation for dairy production, udder health, conformation, longevity, calving (Brown Swiss, Holsteins, Red Dairy Cattle) and fertility  traits is scheduled for August 2008. New data for the August routine run should reach the Interbull Centre not later than Tuesday Aug 5, 2008, 17:00 Central European Time (CET); in any case, the most recently received data will be considered. The target time for distribution of results for internal review to designated representatives, who have signed a confidentiality agreement with the Centre, is Thursday August 14, 2008. Official release date of the results is targeted to be Tuesday August 19, 2008.

Next test international evaluation

The next test international evaluation for dairy production, conformation, udder health, longevity, calving traits (Brown Swiss, Holstein, Red Dairy Cattle) and female fertility traits is scheduled for May 2008. Countries wishing to enter the system for the first time or planning to submit new information (modified national evaluation procedure, new breeds etc) for following routine evaluations must have their data tested in this test-run.

Deadline for sending data and validation results to the Interbull Centre for the May 2008 test evaluation is April 22, 2008 at 17:00 CET.

Means of result distribution from the Interbull Centre

Electronic exchange of data is probably more efficient than anything else. Currently most countries in the service have established internet connections and receive international evaluation results on the day of their release.  Subscribers to the service that do not already has this option are encouraged to consider it and establish an internet connection and ftp account. When such accounts are available, please provide their specifications to the Interbull Centre. Until then, data will be delivered on CD-ROM's.

For more information about the international genetic evaluation service please contact the Interbull Centre: address: SLU Box 7023, 750 07 Uppsala, Sweden; fax: +46-18-672648;

Please use Interbull_at_hgen.slu.se for all communication regarding Interbull services.