Trends on Racing Speed Traits in Thoroughbred Racehorses

더러브렛 경주마의 속도형질에 대한 추세 분석

  • Published : 2008.12.31


This study was carried out to calculate genetic trends on racing speed traits of Thoroughbred racehorses, using a total 208,043 racing records of 9,934 heads collected from January, 1990 to December, 2006 in Gwacheon racecourse. Repeated time, winning time and annual best time were used racing speed traits. The estimated heritabilities and repeatabilities for repeated time, winning time and annual best time were 0.288, 0.275, 0.341 and 0.502, 0.475, 0.496, respectively. Average phenotypic improvement per race year for racing speed traits were ranged from -0.115 to 0.148 second. The other side, the genetic improvement per race year for repeated time was -0.027 second but winning time and annual best time were not shown consistent trends. Therefore, we concluded that repeated time is recommended improvement trait of Thoroughbred racehorses.



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