Interbull Routine Genetic Evaluation for Udder Health Traits

December 2013 

 

Introduction
The latest routine international evaluation for udder traits took place as scheduled at the Interbull Centre. Data from twentysix (26) countries were included in this evaluation.

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

Changes in national procedures
Changes in the national genetic evaluation of udder health traits are as follows:

ZAF (HOL): Test-day model is introduced where test-day records from different parities (parities 1-3) are treated as different traits. An adjustment for heterogeneous residual
variance due to days in milk within parity has been introduced. Stricter editing specifications are being applied, i.e. at least one parent should be known and 
test-day records of a cow are only included from the third test onwards.
 
NOR (RDC): New definition of a rolling calving year, so that the latest year is full 12 months of data. The herd recording system is also changing their datamodel and database platform. 
 
CZE (HOL,SIM): Records of old bulls without proofs are excluded. These bulls were in data files because of pedigree. Now these bulls are in the pedigree file. 
 
SVN (HOL,BSW,SIM): Standardised breeding values BV12 (BV12=((BV-a)/b)*12+100 a=mean b=STD) for all traits and all breeds is used instead of absolute breeding values.
     
LVA (HOL,RDC): Adjusted breed group
  
PRT (HOL): Some changes in info (daughters, herd, EDC) for all traits due to changes in paternities confirmed by DNA tests 
  

INTERBULL CHANGES COMPARED TO THE AUGUST ROUTINE RUN 

Edit on inclusion of import bulls (type of proof = 21) has changed from this test run. An import AI bull with official publication status 'Y' from a given country is included if he has a first country proof included from a different country OR he has a second country proof included from a different country with at least 150 daughters or 150 EDCs in at least 50 herds for Holstein, 30 daughters or 30 EDCs in at least 10 herds for Guernsey, and 80 daughters or 80 EDCs in at least 20 herds for Brown Swiss, Jersey, Red Dairy Cattle, Simmental. 

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 March 2014. Deadline for sending data to the Interbull Centre is Tuesday March 11, 2014, 17:00 CET; confidential distribution of results is targeted for Thursday March 20, 2014, with earliest possible official release of results on April 1, 2014. 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 January 2014.

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 January 14, 2014, 17:00 CET.

PUBLICATION OF INTERBULL TEST RUN

Test evaluation results are meant for review purposes only and should not be published.