A number of important enhancements have been made to the calculation of Estimated Breeding Values (EBVs) for Angus cattle in Australia and New Zealand.
The enhancements form part of the annual updates that are applied to the TransTasman Angus Cattle Evaluation (TACE), with the enhancements implemented in the December 2023 analysis.
The enhancements which were implemented broadly fall in three main categories:
- Optimal use of genomics; including an increase in the relationship weighting applied to genomics for all single-step EBVs and the transition to a single-step model for the Docility EBV.
- Enhanced Research Breeding Values; including updated variance components (heritabilities) for the Mature Body Condition (MBC), Mature Cow Height (MCH), and Coat Type (CT) RBVs. Along with MBC and MCH being transitioned to a single-step model, to be consistent with the CT RBV evaluation model.
- Genetic evaluation efficiency and maintenance; including a more efficient Calving Ease EBV analysis and updates to the contemporary grouping for the days-to-calving trait.
Further information on the annual enhancements which will be implemented in TACE is provided below.