Genetic and Environmental Parameters Effecting Racing Performance of Turk-Arabian Horses Raised at Anatolian State Farm

In this study, some environmental factors and genetic parameters affecting performance of racing for Turk-Arabian horses at different distances raised at Anatolian Agricultural Farms were investigated. In the experiment, 3184 race records of 437 offspring of 32 horses races from 1996 to 2008 were evaluated by two statistical models. The effects of year, hippodrome, track and distance on racing time and race speed were found highly significant (p<0.01). Genetic parameters were estimated by REML procedure using DFREML program. Estimated heritabilities of race finishing times ranged from 0.106 to 0.044 and estimated repeatability from 0.714 to 0.233. Results indicated that a moderates level of genetic progress is possible for racing time if selection is based on the phenotypic value of the horses. For short and medium distance horse breeding values, calculated spearman correlation (0.26) was not significant (p>0.05). This should be taken into account in the breeding program, since the short and medium distance running abilities of horses were independent. In addition, runway type should be considered for estimation of the breeding values. Model-1 and Model-2 provided similar results for racing time. Model-1 (full model) may be preferred to Model-2 as interpretation of racing time abilities for all the factors available via Model-1.