Interbull Routine Genetic Evaluation for Conformation Traits

November 2003

Introduction

International genetic evaluations for conformation traits of Ayrshire, Brown Swiss, Guernsey, Holstein and Jersey bulls from Australia, Belgium, Canada, Czech Republic, Denmark, France, Finland, Germany, Hungary, Italy, Japan, the Netherlands, Norway, New Zealand, Poland, Rep. of South Africa, Spain, Sweden, Switzerland, the United Kingdom, and the United States of America were computed in this routine evaluation.
 

New data (national genetic evaluations) included in this evaluation:

• Ayrshire conformation evaluations were considered for the first time. Countries participating were: Australia, Canada, Denmark, Finland, Norway, New Zealand, Sweden, United Kingdom, and the United States.
   
• The Czech Republic participated in the Holstein evaluation for the first time. However, the three overall conformation traits had to be excluded, since file format errors in the test run made the estimated correlations invalid.
   
•  France provided evaluations for modified definitions of overall conformation and overall udder scores, and improved computations of EDC's for all overall traits, for the Holstein evaluation.
   
•  Italy provided evaluations for modified definition of overall feet and legs for the Holstein evaluation.
   
• The Walloon region of Belgium modified their national evaluations for overall traits. The new evaluations are based on direct assessments of the overall trait, i.e. no longer a composite based on a combination of other direct traits. Also, all lactations are now included in the conformation evaluation.
   
• Japan now include records from cows calving at 18 and 19 months in their national evaluation.
   
• Finland introduced a new data base system with changes in data extraction and handling of genetic evaluations.
   
• Belgium and the Netherlands changed their standardization of breeding values. This is inconsequential with respect to the breeding values in MACE, but affects the estimated sire standard deviations as reported in the appendices.

Changes in Interbull procedures:

• A weighted average of Ayrshire and Holstein genetic correlations were used for Ayrshire Mace as recommended by Mark et al. (2003, Interbull Bull. 30, 126-135).
   
• The trait rear leg rear view was excluded from the Brown Swiss evaluation, and the traits pasterns and foot angle were combined (called pasterns/foot angle).
   
• The trait rear teat placement was included in the Interbull conformation evaluations for all breeds.
   
• All countries are now expected to be identified with their appropriate ISO code. Thus, Czech Rep. is now identified as CZE and Slovenia as SVN.

Data and method of analysis

Data were national genetic evaluations of AI sampled bulls with daughters in at least 10 herds. Table 1, table 2, table 3, table 4 and table 5 presents the amount of data included in this Interbull evaluation for Ayrshire, Brown Swiss, Guernsey, Holstein and Jersey, respectively. Table 6 gives trait definitions as provided by participating countries.

Estimated genetic parameters are shown in APPENDIX I, APPENDIX II, APPENDIX III, APPENDIX IV and APPENDIX V for Ayrshire, Brown Swiss, Guernsey, Holstein and Jersey, respectively. Parameters are listed by trait and country.

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 6).

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). Birth year grouping was by 1-5 year periods. Smaller groups (consisting of less than 15 bulls) were combined.

Analysis followed a similar procedure as Mace for production traits. However, parameters used were estimated with the EM-Reml procedure descriped by Klei & Weigel (1998) and a weighted average of Ayrshire and Holstein genetic correlations were used for Ayrshire Mace as recommended by Mark et al. (2003, Interbull Bull 30, 126-135).


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 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.

Next routine international evaluation

The next routine international evaluation for dairy production, udder health and conformation traits is scheduled for February 2004. New data for that run should reach the Interbull Centre not later than January 27, 2004, 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 February 5, 2004. Official release date of the results is targeted to be February 9, 2004.

Next test international evaluation

The next test international evaluation for dairy production, conformation, and udder health traits is scheduled for March 2004. 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 to the Interbull Centre for the next test-run is March 1, 2004.

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 exercise 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;