Estimation of Genetic Parameters and Annual Trends for Racing Times of Thoroughbred Racehorses

더러브렛 경주마의 주파기록에 대한 유전모수 추정과 연도별 개량량 분석

  • Oh, Seung-Yoon (Interdisciplinary Program in Bioinformatics, Seoul National University) ;
  • Park, Jong-Eun (Department of Agricultural Biotechnology, Seoul National University) ;
  • Lee, Jeong-Ran (Department of Statistics, Seoul National University) ;
  • Lee, Jin-Woo (Korea Racing Authority) ;
  • Oh, Hee-Seok (Department of Statistics, Seoul National University) ;
  • Kim, Hee-Bal (Department of Agricultural Biotechnology, Seoul National University)
  • Received : 2009.02.06
  • Accepted : 2009.04.21
  • Published : 2009.04.01


The aim of this study was to estimate genetic parameters and annual trends on the racing performance of Thoroughbred horses by a statistical analysis of the resulting records. We used the racing results of 245,979 observations for 13,458 horses recorded in 19 years of race held at Seoul and Busan racing tracks, provided by Korea Racing Authority. After a careful adjustment of some variables such as racing times, jockey and trainer numbers and the average prize a horse won, we selected significant factors that explain the result of racing records of a horse by stepwise AIC and BIC methods. The estimated heritability and repeatability were 0.322 and 0.332, respectively. The average of annual phenotypic and genetic improvement was -0.166 seconds and -0.161 seconds, respectively. Based on the statistical approach, we established reasonable animal model of well-set variables, which is important in the study on estimating performance of racing horses.


Thoroughbred;Heritability;Repeatability;Genetic trend


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