Interbull Routine Genetic Evaluation for Dairy Production Traits

August 2013


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:

CHE RHOL/SIM There are some bulls whose number of daughters, herds or EDC slightly decreased for production traits.This is due to changes in the program 
 that we use to extract milk production data from our database.
JPN HOL Because we have corrected some cow's pedigree, number of daughters, number of herds, and EDC decreased in some bulls.  
CHE HOL There were reduction in the number of herds, daughters and EDC. Compared to the previous run, dummy herds for imported animals had been 
 removed. This also caused REL decrease for some traits in some years. Because of changes in publication rules, some bulls changed from official 
to unofficial. The number of bulls had decrease in some years/traits. This was due to deleting dummy herds and also deleting some older bulls 
that were actually "herd bulls". 
ARG HOL We had problems with one of the five programs that send data from the farms. When we changed the data base of the milk recording system in 2009, this 
program started in 2010 to send lactations with most of calvings with the related services in null (without bull). Then we have been reprocessed all 
this information during 2012 and 2013. Nowadays, this program is not used by the milk recording system. That was the only problem we had after the evaluation 
of August 2012. We have not changed anything about the methodology.

INTERBULL CHANGES COMPARED TO THE DECEMBER ROUTINE RUN
No changes in Interbull procedures

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
https://wiki.interbull.org/public/rG%20procedure?action=print

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 December 2013. Deadline for sending data to the Interbull Centre is Tuesday November 12, 2013, 17:00 CET; confidential distribution of results is targeted for Thursday November 21, 2013, with earliest possible official release of results on December 3, 2013. Please  remark the three week turn around time.

OBS!!!! THIS SCHEDULE IS TO BE RATIFIED IN THE NANTES MEETING

Next test international evaluation
The next test run for production, conformation, udder health, longevity, calving, female fertility and workability traits will take place in September 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 September 3, 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.