Genetic analysis of traits from Holsteiner riding horses -: Variance components for performance traits of foals on field test, mares at studbook registration and mares on field and station test
In the present study genetic parameter for performance traits of foals, mares at studbook registration and on test on station and field were estimated. Scores from different inspectors were combined to a single record. Records from test station and field test were used as the same trait. Estimated heritabilities for the performance traits of foals were h(2) = 0.40 (gait/swing) and h(2) = 0.42 (type) on high magnitude. The genetic correlation between these two traits was r(g) = 0.77. Estimates for conformation traits ranged from h(2) = 0.11 and h(2) = 0.12 for traits front and hind legs, over h(2) = 0.19 to h(2) = 0.25 for gait, upper line and push/swing, to high estimates with h(2) = 0.41 for type. The genetic correlations among traits of studbook registration ranged from r(g) = 0.45 to 0.93. The genetic association between hind leg and the remaining traits were estimated between r(g) = 0.45 and 0.57 on moderate magnitude. Estimated heritabilities for performance traits of mares ranged from h(2) = 0.19 (galopp) to h(2) = 0.41 (free jumping). The genetic associations between basic gaits and rideability varied from moderate to high magnitude (r(g) = 0.58 to 0.81). The positive genetic correlations between basic gaits as well as rideability and free jumping indicated no antagonism between these traits (r(g) = 0.22 to 0.48). The genetic correlations between traits of different complexes of performance showed especially between performance traits of foals and traits of studbook registration of mares high correlations. This justifies an early selection of distinct conformation traits in an foal age of 100 days. Estimates of genetic correlations between performance traits of mares on test station and foals ranged mostly on low and moderate magnitude. Equally, correlations between performance traits of mares on test station and at studbook registration were on moderate magnitude. The study showed new results for the selection on conformation traits in a breeding program. Genetic parameters estimated for treated as combined score of different inspectors and combined records collected from testing station and field test of mares contribute to simplification of breeding value estimation for Holsteiner riding horses.