Members are reminded of recent updates to the software used in the calculation of calving ease EBVs. To assist members with messaging to clients around the changes the following has been developed.
Some considerable modifications were implemented into the software that is used to calculate the Calving Ease Direct and Calving Ease Daughters EBVs in December 2019. The modifications were part of an upgrade to the calving ease analysis software so that it is largely consistent with the software that is used to calculate the EBVs for other traits. For the technically minded, this included implementation of a new EBV SOLVER program, improved modelling of genetic groups, a revised procedure for handling calving difficulty scores, and a revised procedure for handling of genomic information. Importantly, the new Calving Ease EBVs now provide a better estimate of each animal’s breeding value.
It is important to be aware that the modifications that have been implemented have resulted in a considerable increase in the standard deviation, or spread of Calving Ease EBVs, when viewing the Calving Ease EBVs for animals in this catalogue. This is illustrated by an increase in the 1% percentile band for the Calving Ease Direct EBV increasing from +5.0 to +12.2. Similarly, the 99% percentile band for the Calving Ease Direct EBV has decreased from -7.6 to -13.1.
Figure 1- Shows the change in spread with the recent updates to the software used to calculate CE EBVs