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Important changes to Holstein UK genetic evaluations for type traits in April 2017

As of April 2017, Holstein UK genetic evaluations for type traits will no longer be calculated by CDN in Canada. This service will now be provided by AHDB Dairy and their contract partners SRUC/EGENES in Edinburgh.

This move has provided an opportunity to review the type evaluation process and a number of important changes are being implemented in April 2017, which are set out below;

1) Type traits will be expressed on a reduced scale, which will result in less extreme values for young genomic bulls in particular. Type scores for the majority of bulls will now lie within 3 standard deviations (or 3 points) from the population mean.
For reference, the table below gives some statistics related to all available Holstein sires;

TM rank Current New
Top TM 4.76 3.73
Top 10 3.79 3.23
Top 25 3.49 3.06
Top 50 3.56 2.84
Top 100 3.37 2.68

2) An enhanced international and genomic evaluation for locomotion will result in more accurate PTA being calculated for this trait. This improvement will result in some bulls having a substantially different PTA result in April 2017, as compared with their previous published value. This is in accordance with an increase in the reliability of their PTA.

3) International daughter information will continue to be included in the calculation of type results for daughter proven sires, even when they reach the standard of ten effective UK daughters. This will allow for a smoother transition of results for those bulls which initially only have international daughters and then gradually acquire UK daughter information.
If you have any queries about these changes please contact;

Darren Todd Direct: 01923 695275
Mobile: 0770 3647139
Email: darrentodd@holstein-uk.org

Marco Winters Direct: 01978 760797
Mobile: 07980 545469
Email: Marco.Winters@ahdb.org.uk