Genetic Evaluation Board (GEB) Executive Summary – February 2019 –

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Source: Canadian Dairy Network

The Genetic Evaluation Board of CDN met on Wednesday, February 13, 2019 at the Holiday Inn in Guelph, Ontario following an Open Industry Session held the previous day. The following is a summary of the discussions and recommendations from the GEB, which will be considered by the Canadian Dairy Network (CDN) Board of Directors at its next meeting scheduled for March 7, 2019.

  •   Brian Anderson from Athlone Farms was re-elected as Chairman of the Genetic Evaluation Board for 2019.
  •   The GEB recommended that CDN proceed with the planned implementation of an updated Pro$ formula for the Holstein and Jersey breeds as well as the first introduction of Pro$ for Ayrshires, effective the April 2019 genetic evaluation release. Specific changes associated with the new Pro$ formula include:

     Updated economic values for revenue based on current milk pricing across Canada. Updated economic values on the expense side of the profit equation, which now include the cost of extra inseminations associated with poor reproduction as well as different daily maintenance costs based on each cow`s estimated relative body size

    •   More accumulated cow lifetime profitability data since Pro$ was originally developed in

      2015.

    •   A Pro$ formula for Jerseys based on cow lifetime profitability data specific to that

      breed.

      In addition, the GEB recommended that CDN implement automated procedures to develop and introduce an updated Pro$ formula annually for each breed, including an annual update to the genetic base used to express published Pro$ values.

  •   In conjunction with the update of the Pro$ formula, the GEB also recommended that CDN update the LPI formula in each breed, effective April 2019, based on the discussions held with the respective breed associations. Although all details of the updated LPI formula will be published separately by CDN, the key changes include:
    •   For all breeds, an increased weight on fat such that it is at least equal to or greater than the weight on protein within the Production component, to reflect national changes in milk pricing in recent years
    •   Changes to the Durability component in Holsteins by including Hoof Health alongside Feet & Legs as well as Rump

      For Ayrshire, with the introduction of Pro$, the LPI formula will shift the relative emphasis on the three components to 46% Production, 32% Durability and 22% Health & Fertility, instead of the current 50:31:19, and also adjust the relative weights on the various traits within each of the three components

    •   The Jersey LPI formula will increase emphasis on the Health & Fertility component relative to Production and Durability, and incorporate some adjustments within each of the three components including the removal of Dairy Strength from Durability
    •   The LPI formula for the other coloured breeds will reflect current breed goals and the desired rate of genetic progress for key traits of importance
    •   In terms of future plans for genetic and genomic evaluation services, the GEB discussed and supported the strategy outlined by CDN to develop and introduce evaluations for additional traits including cystic ovaries, metritis and retained placenta, with April 2020 as the target release date, as well as feed efficiency with a target date of August 2020.
    •   The GEB discussed results from the ongoing work at CDN to develop an improved genetic and genomic evaluation model for calving performance traits, namely calving ease and calf survival. Based on the most recent analyses conducted by CDN, the GEB supported the current direction of implementing a single step genomic evaluation system, with a possible implementation date of December 2019 or April 2020. Results from genomic validation testing and final recommendations associated with the new calving performance system will be presented at the next Open Industry Session in October 2019.
    •   Given the current direction of industry partners to introduce new DHI service options to allow for the remote collection of on-farm production data electronically, without visiting the farm, the GEB discussed how such data could ultimately be included for genetic evaluation. It is expected that the inclusion of milk weights on each data collection date can easily be incorporated into the current Test Day Model used by CDN for production traits. The use of fat and protein components analysis from in-line sensors may also be possible. When discussing how resulting cow evaluations would be published and labelled, the GEB recommended that CDN examine the possibility of making publicly available all cow evaluations based on their own production data, including such evaluations that may completely be based on unsupervised and/or non-verified data. This topic will be openly discussed with industry partners and presented at Open Industry Sessions in the future.
    •   Another topic discussed by the GEB that is of broad interest to Canadian producers, breeders and industry partners is the current and future emphasis placed on stature, especially in the Holstein breed. In general, the GEB supports the recent changes implemented by Holstein Canada related to the assessment of stature and how it contributes to Dairy Strength and consequently to overall Final Score for Conformation. While such changes have an immediate impact on classification results, the GEB recognizes that they take several years of classification data before impacting genetic evaluations. For this reason, the GEB recommended that CDN examine the possibility of moving to composite indexes for the calculation and publication of genetic evaluations for Conformation, Mammary System, Feet & Legs, Dairy Strength and Rump. An expected advantage of this approach is the establishment of composite indexes that reflect the desired direction of selection for traits of intermediate optimums such as Stature, Rear Legs Side View, Teat Length and others. To allow for broad industry discussion and input on this topic, CDN will include it on the agenda for the Open Industry Sessions planned for October 2019 and March/April 2020.
    •   CDN continues to be closely involved in the international effort to address the potential downward bias of progeny proven sires resulting from genomic pre-selection applied by A.I. organizations prior to purchasing genomic young sires. Given the complexity of this issue, any advancement in methods and models to account for this effect is expected to take time.
    •   Following an industry request, the GEB discussed the current policy implemented by CDCB in the United States associated with the availability to CDN of haplotype results for genotyped animals. As a consequence, the GEB recommended that CDN initiate further discussions with CDCB to find a solution such that CDN is able to provide haplotype results for all genotyped animals.
    •   The next Open Industry Session is scheduled to take place on Wednesday, October 9, 2019 in St. Hyacinthe, Québec with the Genetic Evaluation Board meeting the following day.

      If there are any questions, concerns or comments regarding the recommendations of the Genetic Evaluation Board, as outlined in this summary, please feel free to contact committee members listed at http://www.cdn.ca/committees-geb.php or by contacting Brian Van Doormaal directly at Canadian Dairy Network