Samband mellan linjär beskrivning av hoppegenskaper på unghästtest och senare tävlingsprestation hos svenska varmblodiga hästar

Abstract: One goal of the association of Swedish Warmblood horses (SWB) is to be internationally competitive in both dressage and show jumping. Since performances at a high level are achieved late in life, selection is often based on information from young horse tests. Earlier studies have shown that there are strong genetic correlations between traits assessed at young horse tests and future competitions results. There are, however, no studies on which detailed jumping traits that are most important for a successful show jumping career for SWB horses. In 2013, SWB introduced a linear description at young horse test where the horses are described for 50 different traits on a linear scale between two extremes (A to I). The aim of this study was to investigate correlations between linearly described jumping traits at three years of age and show jumping competition results later in life. The question at issue was which linear show jumping traits are most important for the young horse to succeed in its future competition career. The data used in this study consisted of data for 1889 SWB horses that participated in young horse test for 3-year-olds in 2013 and 2014 and their show jumping performance until six and seven years of age, respectively. In 2013 there were eleven different linear jumping traits assessed at young horse test and in 2014 there were fourteen traits. The scale A to I was translated into a numeric scale from one to nine. The studied horses were first divided into subgroups based on age (six or seven years) and if they had competed in show jumping or not. The horses that had competed were divided based on if they had the highest ranking in easy class (L) or intermediate class (M). T-test were used to test if differences between the different groups were significant. The average for the linear traits was around the middle of the linear scale for all traits and all groups of horses: 4 - 6 (D - F). The result showed that horses with higher performance results at competitions generally had a more extreme trait description at three years test towards the left end of the scale (1/A). The most noticeable traits connected with performance were a scope (much- little), take off (powerful- weak), take off: direction (upwards- forwards) and back technique (rounded- hollow). There was also a high correlation between the mentioned linear traits and the describing showjumping scores at three-year tests. All traits differed significantly between horses that had competed and horses that had not competed. For the seven-year-old horses there were no significant differences for the traits haunches technique (open – tight) and carefulness (too careful – not careful) between horses with the highest placement in L class and horses with placement in M class. For the six-year-olds, there was no significant difference between the traits of foreleg technique (bent – hanging) and attitude (focused – not focused) between horses with the highest placement in L class and placement in M class. Remaining traits showed significant differences for both age groups between horses with the highest placement in L class and those with placement in M class. Based on the result, a big scope is the most important jumping trait for a future show jumping horse. A more rounded back technique, a more powerful, more upward take-off also proved to be important based on the linear description at young horse test for 3-year-old SWB horses tested in the years 2013 and 2014.