Beef cattle

Evaluation of Impact of Genomic Data on EBV in Large Multi-breed Beef Cattle Genetic Evaluation

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Abstract

Data from SNP genotyping is one of the fastest growing sources of information entering into beef cattle genetic evaluation systems. Traditionally, the impact in terms of accuracy increase from including genomic information was expressed as progeny equivalents based on increases in EBV accuracy. Inconsistent methodology has been used in different national beef cattle evaluations to arrive at those estimates. The objective of this research was to estimate the impact on accuracy of genotyping non-parent animals in a large multi-breed genetic evaluation. To this end, two genetic evaluations were conducted. The first (Full Run) contained all data and information that was traditionally included in the published weekly runs, whereas the second (Partial Run) had all phenotypes from animals born after 1/1/2024 removed from the analysis. Analysis was then performed on those 31,577 genotyped animals born after 1/1/2024 by regressing de-regressed across-breed EBVs from the full analysis on the Breed Covariates (BC) and EBV from the truncated analysise. Breed covariates included Angus, Gelbvieh, Shorthorn, South Devon, Hereford, Red Angus, Limousin, other continental, and others. The MS effect was derived from the genotype data included in the analysis. A Coefficient of Determination (R2) was calculated for the model to determine the amount of variation in the de-regressed full EBVs is accounted for. To calculate the R2 resulting from using genotypic data, and converted to progeny equivalents, selection index methodology for the regression of sire EBV on a number of offspring records was computed using a heritability of 0.23. The resulting R2 for the Docility model was 0.37. This would correspond to a requirement of 10 progeny records to reach this level of reliability for Docility. This approach to calculation of the impact of genomic information in routine genetic evaluation provide a metric to compare the increase in accuracy of non-parent animals for selection decisions.

Keywords: 2026

How to Cite:

Boldt, R. & Garrick, D., (2026) “Evaluation of Impact of Genomic Data on EBV in Large Multi-breed Beef Cattle Genetic Evaluation”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2286682. doi: https://doi.org/10.31274/wcgalp.24095

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