ANGUS CATTLE EVALUATION
December 2025
ANNUAL ENHANCEMENTS TO THE TRANSTASMAN ANGUS
CATTLE EVALUATION
December 2025
Dear Angus Breeders,
This document includes details of the 2025 annual enhancements for inclusion in the TransTasman Angus Cattle Evaluation (TACE). The enhancements are scheduled for implementation in the December 2025 analysis, being the analysis where the Estimated Breeding Values (EBVs) are released on approximately November 27th, 2025.
The annual enhancements that are made to TACE ensure that the EBVs published for Angus animals continue to be the best possible estimate of an animal’s breeding value, maximising the genetic improvement that is being achieved in Angus breeding programs.
The 2025 TACE Enhancements focus on two key areas:
Please contact staff at Angus Australia if you have any questions. A list of contacts is provided on page 3.
Regards
Scott Wright
Carel Teseling Chief Executive Officer Chief Operational Officer
1. ENHANCEMENTS TO THE GENETIC EVALUATION OF MATURE BODY COMPOSITION TRAITS AND COAT TYPE
The December 2025 updates include refinements to the evaluation of Mature Body Condition (MBC), Mature Cow Height (MCH), and Coat Type (CT) traits. These enhancements form an important part of the ongoing maintenance of the TransTasman Angus Cattle Evaluation model and data pipeline, ensuring EBVs remain accurate, stable, and relevant for modern breeding objectives.
Key points:
• SNP density increase: The SNP density used in the genotype imputation pipeline in preparation for the single-step genetic evaluation of MBC, MCH, and CT has increased from 45,364 SNPs to 61,105 SNPs. More genomic information improves EBV accuracy and stability.
• Minimal impact on animal rankings: Correlations between preand post-enhancement EBVs remain high (>0.95), ensuring breeders can continue selecting with confidence.
• Subtle improvements to EBV accuracy: Particularly for younger animals or those with fewer recorded measurements.
• Unchanged reporting: EBV interpretation, reporting, and placement on angus.tech remain the same.
A key refinement, in 2025, is the increase in the SNP density used in the genotype imputation pipeline in preparation for the single-step genetic evaluation of MBC, MCH, and CT, from 45,364 SNPs to 61,105 SNPs. Imputation is the process of filling in missing SNPs, which can occur when animals are genotyped with different SNP panels or when some markers fail quality checks. By using the higher-density SNP set to fill these gaps, each animal has a complete and consistent genotype, improving the accuracy and stability of EBVs. These enhancements allow breeders to make more informed selection decisions for mature cow composition and coat type.
Importantly, these refinements are minor, meaning that EBVs remain largely consistent with previous evaluations. Correlations between EBVs before and after the enhancements are high (>0.95), indicating that animal rankings within herds are largely unchanged, and breeders can continue selecting with confidence. EBV accuracies may improve slightly, particularly for younger animals or those with fewer recorded measurements, but overall, these refinements are subtle, supporting stability while improving precision.
The figures compare the previous MBC & MCH EBVs (based on 45k SNPs) with the updated MBC & MCH EBVs (based on 61k SNPs) for both sires with higher (≥75%) and moderate (≥50%) accuracy. The comparison demonstrates a strong correlation between the previous and updated MBC & MCH EBVs (>0.95), with regression slopes close to 1 and minimal changes to the intercepts. Correlations between the previous and updated CT EBVs were also high (>0.98) for both sires with higher (≥75%) and moderate (≥50%) accuracy. This indicates that the relative ranking of animals has remained largely unchanged.
The patterns observed are consistent across both high- and moderate-accuracy sires, showing that the refinement applies uniformly across the population. While the updated EBVs are on
Figure 1. Scatter plot comparing EBVs pre- vs post-enhancement for MBC and MCH traits, highlighting high correlation (>0.95) and minimal re-ranking for both high (>75%) and moderate (>50%) accuracy sires.
average slightly higher, the shift is minor and does not materially affect selection decisions. Overall, the increase in SNP density has enhanced the precision of EBVs while maintaining stability in herd rankings, allowing breeders to continue using existing selection decisions with confidence.
Interpretation reminder:
• Mature Body Condition EBVs estimate genetic differences between animals in the body condition of mature females. Higher EBVs indicate daughters likely to maintain more body condition, at weaning.
• Mature Cow Height EBVs estimate genetic differences in the height of mature females. Higher EBVs indicate taller mature females.
• Coat Type EBVs estimate genetic differences in coat characteristics. Lower Coat Type RBVs indicate an animal is expected to produce progeny with a shorter, slicker coat.
Additionally, Angus Australia is committed to ensuring that our genetic evaluation model and data pipelines remain efficient and accurate. As a result, as part of the 2025 TACE Enhancements, additional updates were applied to the MBC, MCH & CT model and data pipeline to increase the efficiency and accuracy of the overall evaluation.
2. POTENTIAL CHANGES TO EBVS AND ACCURACIES AS ANGUS NEW ZEALAND MIGRATES TO A NEW DATA RECORDING SYSTEM
The TransTasman Angus Cattle Evaluation (TACE) is an international genetic evaluation, combining pedigree, performance, and genomic information from both the Angus Australia and Angus New Zealand databases. This integrated dataset ensures EBVs are robust, reliable, and relevant for breeders in both countries, supporting informed selection decisions.
The transition of Angus New Zealand (AngusNZ) to a new data recording system will result in minor changes to some animals EBVs and accuracies in the December 2025 TACE analysis. While this primarily affects the New Zealand portion of the TACE population, some Australian animals may also experience slight adjustments due to shared pedigree and genomic linkages across the Trans-Tasman genetic evaluation.
Overall rankings within herds are expected to remain largely unchanged, while the refinements help ensure EBVs and accuracies reflect the latest data and pedigree structure
Key points:
• Minimal breed-level impact: EBV correlations between the evaluation pre- and post- AngusNZ’s migration to the new data recording system remain high (>0.99), ensuring breeders can continue selecting with confidence.
• High overall consistency: Limited impact on herd selection decisions; animal rankings largely consistent.
• Source of EBV movements: For those animals where EBV changes are observed, the adjustments appear to arise from updated or removed pedigree and genomic information within the AngusNZ system.
SUPPORTING THE ONGOING DEVELOPMENT OF ANGUS BREEDING
The TACE updates reflect Angus Australia’s ongoing focus on supporting progressive and informed breeding decisions. Each year, refinements are applied to ensure EBVs, and selection tools remain relevant, reliable, and practical for breeders in making decisions for their herds.
Carel Teseling, Chief Operations Officer at Angus Australia, said, “These refinements help ensure TACE continues to provide breeders with clear and reliable information to guide selection decisions while keeping pace with the data and technology available today.”
Nancy Crawshaw, Extension Manager at Angus Australia, added, “The annual updates are part of our ongoing commitment to supporting members with practical tools for herd improvement. We encourage members to review the updates and consider how they may inform their breeding decisions.”
Ongoing support for Angus Australia members
To ensure that all members are well-informed about the December updates, Nancy Crawshaw, Extension Manager at Angus Australia, advised that comprehensive explanatory materials was distributed to Angus Australia members in November and available from the Angus Australia website. These resources provide clear guidance on how the changes will affect breeding decisions and how to make the most of the new tools.
“We encourage our members to reach out with any questions they may have about the 2025 TACE enhancements,” said Ms. Crawshaw. “Our team is here to support breeders as they navigate these refinements.”
CONTACTS FOR FURTHER INFORMATION
To further discuss any of the enhancements implemented in the December 2025 TransTasman Angus Cattle Evaluation, please contact members of Angus Australia’s Genetic Improvement and Extension team.
Nancy Crawshaw
Extension Manager
Ph: +61 2 6773 4643
E: nancy.crawshaw@angusaustralia.com.au
Brad Hine
Extension Officer
Ph: +61 2 6773 4613
E: brad.hine@angusaustralia.com.au
Hanlie Jansen
Genetic Improvement Specialist
Ph: +61 2 6773 4641
E: hanlie.jansen@angusaustralia.com.au
Malshani Samaraweera
Geneticist
Ph: +61 2 6773 4622
E: Malshani@angusaustralia.com.au
