Interbull Routine Genetic Evaluation for Dairy Production Traits

April 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:

SVN HOL, BSW, SIM BV:s multiplied with 100 instead of 1000 as done previously
 
LTU HOL, RDC We changed the model a little bit: We added crossbreed cows as different population so now we have 4 populations 1 red 2 black and white, 3 black 
and white bull*red cows 4 red bulls*black and white cows as we added the population we increased the control of false data the test records count 
for a lactation. The population is not big and bulls do not have a lot of daughters.
ITA HOL, JER Base change and exclusion of cows calving before January 1997 
 
AUS HOL, JER, RDC, GUE Base change
CHE RHOL Base change
 
CHE HOL New publication rules causing some bulls to change from official to unofficial.
JPN HOL Correction of some cow's pedigree
DEU HOL, RDC Small decreases in number of daughters/herds/EDC due to constant update of sire identities and systematic breed correction of cows/daughters. 
NOR RDC Base change

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 August 2013. Deadline for sending data to the Interbull Centre is Tuesday July 23, 2013, 17:00 CET; confidential distribution of results is targeted for Thursday August 1, 2013, with earliest possible official release of results on August 13, 2013. Please remark the three week turn around time.

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.