著者

Kazuhiro KAMIYA Hajime OHMURA Daisuke ETO Kazutaka MUKAI Shigeto USHIYA Atsushi HIRAGA Sadao YOKOTA

出版者

Japanese Society of Equine Science

雑誌

Journal of Equine Science (ISSN:13403516)

巻号頁・発行日

vol.14, no.3, pp.97-100, 2003 (Released:2003-12-19)

参考文献数

13

被引用文献数

1

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T. M. Opera O is considered as one of the greatest racehorses in the history of horseracing in Japan. Only a very few data is available on circulatory function of elite Thoroughbred racehorses. Recently, we obtained data on circulatory parameters of T. M. Opera O. The left ventricular mass of T. M. Opera O, as measured on an echocardiogram, was 4.60 kg. The resting heart rate (HR) of T. M. Opera O was 25 beat/min. The low-frequency and high-frequency power, as determined by an analysis of HR variability, were 13,900 and 5.963 ms2, respectively, which were considerably higher than those of the other racehorses. These results suggest that a large heart, formed by genetic factors and training, markedly enhanced the parasympathetic nervous activity and reduced the resting HR of T. M. Opera O. The data we obtained from T. M. Opera O is invaluable for understanding the physical fitness of elite Thoroughbreds and for further developing their athletic performance.