Influence of imported sport horses on the genetic evaluation of Swedish warmblood stallions

Abstract

There is substantial international influence on the Swedish Warmblood (SWB) sport horse population. The SWB Association suspects that imported horses are pre-selected based on their anticipated performance level, which could lead to biased estimated breeding values (EBVs) for stallions. This study examined different strategies to handle records for imported horses in the genetic evaluation. The stallions were evaluated for 10 traits using 3 different EBV estimation methods that were compared based on ranking comparisons of stallions, accuracy, correlations and absolute differences between EBVs. The results showed that the stallions’ EBVs were affected by imported offspring which, as a group, had higher average scores than horses born in Sweden. Sire EBVs differed by up to 0.6 genetic standard deviation of the trait between methods for stallions with >50% imported offspring. Excluding imported offspring lowered the accuracies and caused larger re-ranking compared with including a fixed effect of origin in the model.

Keywords

Correlation; estimated breeding value; pre-selection; dressage; showjumping

Published in

Acta Agriculturae Scandinavica, Section A - Animal Science
2016, Volume: 66, number: 4, pages: 183-189

SLU Authors

• Pettersson, Maria

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    

• Eriksson, Susanne

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    

• Gelinder Viklund, Åsa

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Animal and Dairy Science


Publication identifier

DOI: https://doi.org/10.1080/09064702.2017.1346702

Permanent link to this page (URI)

https://res.slu.se/id/publ/85748