Usefulness of international dairy bull evaluations

1. Usefulness of international dairy bull evaluations Rex L. Powell Animal Improvement Programs Laboratory Agricultural Research Service, USDA, Beltsville, MD rpowell@aipl.arsusda.gov

2. Interbull Formed • IDF and EAAP activities • 1982 - Leningrad meeting • 1983 - Interbull formed • 1988 - Became ICAR committee • 1991 - Centre established

3. Interbull Centre • Site: Uppsala, Sweden • Responsibilities and activities: • Steering committee sets policy • General operations by staff • Global service provider

4. Interbull Evaluation Process • National evaluations sent to Centre • MACE combines pedigree and national evaluation data • Estimated genetic correlations applied • Evaluations returned to countries on their own scale • Officiality responsibility of countries

5. Sending Receiving 25 20 15 No. countries 10 5 0 Feb-99 Aug-94 Aug-95 Aug-99 Aug-96 Aug-97 Aug-98 Evaluation date Countries Participating in Service

6. Numbers of Countries per Bull 100 94.6 80 60 Percentage of Bulls 40 20 3.8 0.8 0.3 0.1 0.1 0.1 0.1 0.1 0 1 2 3 4 5 6 7 8 9+ Number of countries

7. Question Do foreign data aid in prediction of future national evaluations?

8. Data Best Predictor? NATIONAL NATIONAL Study Design 1995 1999

9. NATIONAL NATIONAL Study Design 1995 1999 r SD r SD

10. Data • February 1995 Interbull evaluations • National 1995 evaluations • National 1999 evaluations • Canada, Germany, Italy, Netherlands, USA

11. Answers • Foreign data improved prediction • Improvement greatest for imported bulls • Interbull evaluations should be official

12. Top 100 Bulls for Yield (USA)Based on Official Evaluations Source: Interbull and domestic, February 2001

13. Top 100 Bulls for Yield (NLD)Based on Official Evaluations Source: Interbull and domestic, February 2001

14. Top 100 Bulls for Yield (CAN)Based on Official Evaluations Source: Interbull and domestic, February 2001

15. Top 100 Bulls for Yield (HUN)Based on Official Evaluations Source: Interbull, February 2001

16. Top 100 Bulls for Yield (CSK)Based on Official Evaluations Source: Interbull, February 2001

17. Use of Reliability • Measure of accuracy • Guides how much to use a bull, not whether to use a bull • Minimum restricts the number of bulls • Limiting bulls limits progress

18. Impact of Minimum REL On Number of Bulls & Mean PTAP of Top 50 (USA) Source: Interbull, May 2001

19. Impact of Minimum REL On Number of Bulls & Mean PTAP of Top 50 (HUN) Source: Interbull, May 2001

20. Impact of Minimum REL On Number of Bulls & Mean PTAP of Top 50 (CSK) Source: Interbull, May 2001

21. Websites • interbull.org • Publications & bulletins • Evaluation summaries • aipl.arsusda.gov • Documents • Downloadable files • Access to all evaluations

22. Conclusions • Interbull Centre young and growing • Rankings differ by country • Foreign data improve prediction of later national evaluations • Most gain is from considering all bulls on one scale • Challenges remain in technical areas and in education

23. Foreign Bull Options • Top 100 on HGI • HGI as high as 10th HUN bull and • HUN REL 75% for production • HUN REL 70% for conformation • Nominated and approved

24. Foreign Bulls In & Out • 367 bulls on HGI combined list • Includes 68 of top 200 on US Net Merit • Bulls from all countries eligible for US NM$ list • 6 of top 12 for NM$ not included on HGI list (among them #2) • 3 of top 8 on TPI not included • #1 not included

25. Foreign Bulls Excluded 1Protein and REL from Hungarian scaled MACE 2Reliability of evaluation in home country of bull

26. Reliabilities on Hungarian Scale