Effects of Change of Body Weight on Racing Time in Thoroughbred Racehorses

더러브렛 경주마의 체중변화가 주파기록에 미치는 효과

  • Published : 2008.12.31


The objective of this study was to estimate the effects of change in body weight on racing time in Thoroughbred racehorses, using total 8,197 horses and 155,656 racing records collected from Korea Racing Association(KRA). The average body weight of the racehorses was 449kg, and the average body weights of stallion, gelding and mare were 460kg, 454kg and 441kg, respectively. Body weight of stallion was the greatest. The considerable loss of body weight was observed in March, April and May for mare, and in May, Jun and July for stallion and gelding. Overall, the body weight of the racehorses decreased in spring and summer, and increased in autumn and winter. The estimated heritability and repeatability for racing time were 0.237 and 0.525, respectively. The heritability for body weight estimated from total records was 0.612. The estimated heri- tabilities for body weight were 0.472, 0.578 and 0.555 for gelding, stallion and mare, respectively. As the change of body weight was greater than ±10kg, the racing time increased significantly. When the body weight changed more than ±20kg in comparison to the changes of body weight of ±5kg, the racing time increased by 0.3 second. When the change of body weight was ±0.5% of body weight, the racing time was the best(fastest). When the change of body weight was more than ±2.5%, racing performance decreased considerably.



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