With the August 2019 proof round comes a complete revision of the fertility evaluations. This means previous seasonal fluctuations in a bull’s value for Daughter Pregnancy Rate (DPR) should now be a thing of the past.
This adjustment will also improve the stability of a bull’s values for Cow Conception Rate (CCR) and Heifer Conception Rate (HCR).
The simple, primary reason that DPR fluctuated from one proof to the next was that seasonal groupings used for the calculations were previously based on heifer breeding dates instead of cow breeding dates.
After correcting the seasonal groupings, CDCB reran the past four proof evaluations and saw a much more stable trend for all fertility traits. This means you can have confidence that the lingering instability should now be resolved.
This means you can trust that selection for DPR, CCR or HCR within your customized genetic plan will help you create more fertile, Alta 4-EVENT COWS.
What does that mean for this proof round?
With this August proof adjustment, the average industry values for DPR, CCR, and HCR did drop slightly. The table below outlines the overall average drop for these fertility traits in the Holstein and Jersey breeds.
|Young genomic Holstein bulls||Dtr-proven Holstein bulls||Young genomic Jersey bulls||Dtr-proven Jersey bulls|
|Average DPR change from April to August 2019||-0.6||-0.3||-0.3||0.0|