Source: Lactanet
written by: Cindy Jaton, agr., MBA, Ph.D and Hannah Sweett, Ph. D.
Lactanet will soon be offering monthly official genetic evaluations for cows and heifers in milk-recorded herds. These more frequent female evaluations, which are scheduled to start in October 2025, allow for faster access to up-to-date data and improved accuracy for decision-making.
Since 2007, official cow evaluations have been updated three times a year to include additional data within evaluations, implying that the official genetic evaluations for females stay the same for four months. Specific milk recording requirements are needed for an evaluation to be official (EBV) and those not meeting the requirements receive parent average (PA) values as their official evaluation. Similarly, for type evaluations, a classification in first lactation is required for a cow to get an official evaluation. However, an opportunity exists for Lactanet to revise the publication of official evaluations using the most complete and current data.
With official evaluations being updated in April, August and December each year, data cut-off dates are scheduled approximately six weeks prior to each official release to allow enough time to receive and process national and international data, including MACE evaluations from Interbull. By moving to monthly official evaluations, the same cut-off dates will be applied for usual tri-annual releases for all bulls and females. For the other nine months, however, all data accumulated up to roughly two weeks prior to the monthly release date, usually on the first Tuesday, will be used to calculate updated official genetic evaluations for cows in Canada and their affected female relatives, mainly daughters. For example, the cut off for the October 7, 2025, release would be Friday, September 19, 2025. This means any data received by Lactanet in between that time would not meet the cut off for the October release and would be included in the next monthly update on November 4, 2025.
What are the benefits of more frequent female evaluations?
Providing Canadian females with monthly official genetic evaluations will:
- Provide faster access to updated genetic data, allowing Canadian producers to make more timely selection and mating decisions
- Improve accuracy of cow evaluations as performance data is added
- Expand opportunities for cows and heifers to appear in top animal lists searchable on the LactanetGen.ca website
Which females will be updated?
The Lactanet database currently includes over 35 million animals, with the vast majority being females. The focus of moving to more frequent updates of official genetic evaluations is to provide the most current evaluation possible for cows in Canadian herds and any female relative that may be affected by updated evaluations. For this reason, the criteria for identifying the cows and heifers in Canada that will receive an updated evaluation are as follows:
- Cows that received an official EBV at the most recent tri-annual release (i.e.: in April, August or December) and have added new milk-recording data to their genetic evaluation for production traits.
- Cows that have added milk-recording data for production or a first lactation classification to receive their first official EBV for production and/or conformation traits.
- Female relatives of these cows adding new data, including daughters, dam, and sisters that have an “Active” status in the Canadian population, will also be updated if their LPI or the LPI subindex values change significantly compared to those officially published for the previous tri-annual release.
How will updated cows and heifers be identified on the LactanetGen.ca website?
The new monthly official genetic evaluations will be displayed on the LactanetGen.ca website for females meeting the criteria for each monthly update, usually on the first Tuesday of the month. For the expected update on 7 October, 2025, the genetic evaluation run date displayed will change from 25*AUG to 25*OCT, including newly genotyped females. All males and any females not updated during a monthly release will continue to show a date of 25*AUG until the next official tri-annual release in December 2025.
Will bull evaluations be affected?
Official bull evaluations will not change between the official tri-annual releases, except when moving from PA to GPA and/or if there are pedigree changes. That said, the monthly female evaluations between official proof releases will also reflect changes in the monthly interim evaluations of their sire, maternal grandsire, etc. Canadian female evaluations will therefore always reflect the most recent data for them and their female relatives in Canada!
Coming December 2025
Currently, Lactanet calculates two different cow evaluations for production traits, depending on the inclusion of supervised test day records. For cows enrolled on a “Publishable” milk-recording service, cows normally qualify to receive an “official” EBV for production traits. For cows in herds without sufficient supervised milk-recording data, Lactanet calculates “management” production indexes, which have been updated monthly for the herd owner’s use. These “Official” and “Management” evaluations for production traits, as well as LPI and Pro$ values, are used for Lactanet’s Genetic Herd Inventory reports, Compass and DairyComp, and are also shared with AI companies offering genetic mating programs in Canada. Cows with “Management” production indexes receive Parent Average (PA) values on the Lactanet and breed association websites.
The fact that some cows and heifers have had different genetic evaluations available depending on the degree of supervised testing has been a longstanding source of confusion. However, starting December 2025, each female will only have one genetic evaluation available regardless of whether the herd is enrolled on supervised milk recording or not. Top lists for cows will therefore include qualifying cows that are currently considered as having an unofficial “Management” genetic evaluation for production traits as well as LPI and Pro$. Keep an eye out for additional information closer to December.
Summary
Starting withy the monthly release on October 7, 2025, cows on milk recording in Canada will receive monthly official genetic evaluations with the most up-to-date information. This move aligns with industry trends toward enhanced data collection, helping producers make accurate genetic decisions. Later this year, cows will also only receive one production evaluation regardless of the data source.
