Interbull Routine Genetic Evaluation for Direct Longevity Traits

May 2006

Introduction
International genetic evaluations for direct longevity of bulls from Australia, Belgium, Canada, Switzerland, Germany, Denmark, Spain, Finland, France, The  United Kingdom, Ireland, Israel, Italy, New Zealand, The Netherlands, and The United States of America were computed in this evaluation for Ayrshire, Brown Swiss, Guernsey, Jersey, Holstein and the Simmental breed.

Changes in national data compared to:
- February 2006 routine evaluations

• Canada changed from a three trait model to a five trait model. Survival in first lactation was divided into three traits (survival from 0-120 DIM, 121-240 DIM, and 241 DIM to next calving) and survival in 2nd and 3rd lactation were considered as the 4th and 5th trait, respectively.
   

Changes in international evaluations compared to:
-  February 2006 routine evaluations

• Direction of scale was included.

Data and method of analysis of sire variances were implemented

Data were national genetic evaluations of AI sampled bulls with daughters in at least 10 herds. Table 1 presents the amount of data included in this Interbull evaluation. 

Table 2 presents the date of evaluation as supplied by each country in the 017-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. Different breeds were analysed separately. Heritability estimates used in both the de-regression and international evaluation were as in each country's national evaluation (Table 3).

Estimated genetic parameters are shown in APPENDIX I and the corresponding number of common bulls are listed in APPENDIX II. Parameters are listed by breed, trait and country.

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 (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 and calving traits (Holsteins, Ayrshire, Brown Swiss) is scheduled for August 2006. New data for the August routine run should reach the Interbull Centre not later than Tuesday July 25, 2006, 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 3, 2006. Official release date of the results is targeted to be Monday, August 7, 2006.

Next test international evaluation

The next test international evaluation for dairy production, conformation, udder health, longevity and calving traits (Holstein, Ayrshire, Brown Swiss) is scheduled  for September 2006. Countries wishing to enter the system for the first time or planning to submit new information (modified national evaluation procedure, newbreeds 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 September 2006 test evaluation is September 1, 2005 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.