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December 2021: Changes to Evaluation System
Kristen Parker Gaddis and Paul VanRaden
December 1, 2021
Genetic evaluations for Residual Feed Intake (RFI) were improved using variance adjustments and a higher estimated heritability. The RFI records are now
adjusted to have equal variance across herds and across first versus later parities.
Mahesh Neupane and Kristen Parker Gaddis and Paul VanRaden and Rob Tempelman
August 1, 2021
The new Lifetime Net Merit (NM$) including Feed Saved (FSAV), Heifer Livability (HLIV) and Early First Calving (EFC), along with a number of new parameters and
assumptions, will be introduced in the August 2021 evaluation.
Several small adjustments to fertility traits editing will be introduced with the April 2021 evaluation to better account for late-term abortions. Fertility credits for traits
Heifer Conception Rate (HCR) and Cow Conception Rate (CCR) now treat the last service as a failure instead of success if the next calving is coded as an abortion.