Evaluation of the length of competitive life in Hungarian sport horses.

The research conducts an in-depth analysis of the competitive lifespan of jumping horses in Hungary and investigates potential genetic and risk factors that may affect their performance.

Objective of Research

• The primary objective of this study was to analyse the competitive lifespan of jumping horses in Hungary. This information would help assess to what extent genetic evaluation can predict a horse’s performance, and also identify risk factors that might influence the horse’s performance.

Data Collection

• The researchers collected data of lifetime performances in jumping competitions of 8475 horses born from 1992 onwards. These records were collected between the years 1996 and 2011, with 32.7% of the data being right-censored.
• The number of years the horses spent in competitions was taken as the measure of their competitive longevity.

Model and Variables

• A discrete-time survival model was used for evaluation, which included fixed effects of gender, age at first competition, and competition level as time-dependent effects.
• All of these fixed effects showed high significance (p < 0.001).

Findings

• The researchers noted that horses competing in lower level events (category 1) had the highest risk of ending their racing career.
• Conversely, horses competing in the highest category events showed the lowest risk.
• Stallions exhibited 15% higher culling risk, while geldings demonstrated a 20% lower risk in comparison to mares.
• Risk ratio increased as the age at first competition increased. For horses that began competing at the age of 8 or older, the risk ratio was 56% higher than for 5-year-old horses.
• Horses that began their career at 4 years of age spent the longest time in sports tracks. Their risk of culling was 20% lower than those that started at the age of 5.

Genetic Findings

• The heritability of the length of competitive life was found to be 0.17, suggesting moderate genetic influence.
• Breeding values were predicted for each horse, and 47 of them showed an accuracy greater than 0.60. The efficacy of these breeding values was illustrated by comparing offspring to extreme stallion groups.

Implications

• The findings of this research shed light on the factors influencing the competitive longevity of sport horses. These insights could prove crucial in identifying and breeding potential champion horses in the future.