Epsilon Archive for Student Projects

Abstract

Genetic evaluation is an important tool in sport horse breeding, as it supports selection of horses with favourable genetic potential for competition performance. In the Swedish Warmblood horse, competition performance is currently evaluated using Lifetime Accumulated Points (LAP), which has limitations because points are mainly awarded to placed horses at higher competition levels. Therefore, alternative performance traits may be useful for improving the use of competition data in genetic evaluation. The aim of this study was to analyse show jumping and dressage competition data from Swedish Warmblood horses and investigate whether Highest Level Achieved (HL) was suitable for use in SWB genetic evaluation.
The data consisted of competition records from the Swedish Equestrian Federation from April 2009 to January 2026. Highest Level Achieved was defined separately for dressage and show jumping according to the highest competition level reached by each horse. Genetic parameters were estimated using animal models, and breeding values, accuracies, stallion rankings and genetic trends were compared with the current genetic evaluation. Genetic correlations between HL and young horse performance test traits were also estimated.
Heritability estimates were moderate to high for both disciplines though slightly higher for show jumping than for dressage, with estimates of 0.44 and 0.33, respectively. The rank-correlations for the new EBV (EBVhl) and the official EBV (EBVlap) were high, 0.86, but not close to unity. Some re-ranking of stallions did occur for the top 30 breeding stallions. The genetic trends were positive and showed good genetic progress over time. Genetic correlations between HL and young horse test traits varied based on discipline, supporting earlier findings of discipline specialisation within the breed.
Overall, HL appears to be a good and genetically informative trait for evaluating SWB competition performance. However, it is also influenced by opportunity to compete, rider, management and longevity, which should be considered in future evaluations.