Interbull Routine Genetic Evaluation for Dairy Production Traits

January 2009


Introduction

The latest test international evaluation for dairy production traits took place as scheduled at the Interbull Centre. Data from twenty seven (27) countries were included in this evaluation. Results were distributed on January 8, 2009, to designated representatives.

International genetic evaluations for milk, fat and protein yields of bulls from Australia, Austria, Belgium, Canada, Czech Republic, Denmark, Estonia, Finland, France, Germany, Hungary, Ireland, Israel, Italy, Japan, Latvia, Netherlands,New Zealand, Norway, Poland, Rep. of South Africa, Slovak Republic, Slovenia, Spain, Sweden, Switzerland, the United Kingdom, and the United States of America were computed. Brown Swiss, Guernsey, Holstein, Jersey, Red Dairy Cattle and Simmental breed data were included in this evaluation.

New data (national genetic evaluations) included in this evaluation

DFS (RDC) Correction of a minor error for Finnish cow's. They have not been corrected for days carried calf in a proper way.
    
DFS (JER) Inclusion of Swedish Jerseys (small population).
     
EST (HOL,RDC) Inclusion of additional bulls with daughters in less then 10 herds.
     
DEU (HOL,RDC) Few id changes
     
ITA (HOL) Introduced DIM and a 4 seasons effect in the model.
     
NOR (RDC) Used Pete Sullivans program to cumpute EDC's.
     
USA (ALL) Used multi-trait instead of single-trait best prediction to calculate milk, fat, and protein lactation records.
     
CHE (HOL) Id changes in cooperation with the Swiss Red & White Breeders Association. Red & White bulls have been mentioned RED instead of HOL.
     
CAN (ALL) Adjustment for pregnancy and a small change in contemporary group definition (impact is small).
     
SVK (HOL,SIM) Participated for the first time in a routine run.
     
GBR (JER) The main change for JER is the merging of records from Jersey Island (not previously submitted to Interbull) with those from the mainland (previously submitted to  Interbull). Until now Jersey evaluations were based only on mainland daughter records and bulls from the island that have daughters already on the Island but used on the mainland were treated as foreign bulls and thus coded with status '21'. The merging of both data sets means that these bulls are now coded '12' and they are no longer considered foreign bulls. This explains why many bulls have changed status. Secondly, the loss of EDC by a number of bulls is due to changes in herd-test day coding as a result of combining both data sets.
     
GBR (RDC) The main change for RDC is the inclusion of additional animals with pedigree status X at the request of the RDC society.
     
NLD  (ALL) - change of database for Flemish data (data from Luxembourg still used)
     

Changes in Interbull procedures

Data and method of analysis

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. The difference between "No. Records" and "No. Bulls" is explained by common bulls with proofs in more than one country. The entry "Publishable Proofs" reflects bulls whose international evaluations were distributed to service customers. The difference between "No. Bulls" and "Publishable Proofs" is explained by bulls not meeting the minimum criterion for official publication in the country of origin.

Tables 2 and table 3 presents the current definition of the reference (genetic) base and date of evaluation, respectively, as supplied by each country in the dairy-production proof file.

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.

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 4).

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. Small groups (generally consisting of less than 10 bull) were combined.

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
Genetic correlation estimation procedure

Time edits

Weigel and Banos. 1997. J. Dairy Sci. 80:3425-3430

International reliability estimation

Harris and Johnson. 1998. Interbull Bulletin 17:31-36

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 (http://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, calving (Brown Swiss, Holsteins, Red Dairy Cattle), fertility and workability traits is scheduled for April 2009. New data for the April routine run should reach the Interbull Centre not later than Tuesday March 24, 2009, 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 April 2, 2009. Official release date of the results is targeted to be Tuesday April 7, 2009.

Next test international evaluation

The next test international evaluation for dairy production, conformation, udder health, longevity and calving traits (Red dairy cattle breed, Brown Swiss, Holstein) and female fertility traits is scheduled for May 2008. 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 and validation results to the Interbull Centre for the next test-run is April 28, 2008 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 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;

e-mail: Joao Durr_at_hgen.slu.se Phone: +46-18-672098
  Flavio.Forabosco_at_hgen.slu.se   +46-18-671974
  Jette.Jakobsen_at_hgen.slu.se   +46-18-671955
Eva.Hjerpe_at_hgen.slu.se +46-18-672438
Hossein.Jorjani_at_hgen.slu.se +46-18-671964
  Anne.Torsell_at_hgen.slu.se   +46-18-671975
Jan.Philipsson_at_hgen.slu.se +46-18-671976
Dan.Englund_at_hgen.slu.se +46-18-671968

Please use Interbull_at_hgen.slu.se  for all communication regarding Interbull services.