Abstract
In order to estimate the change of a number of body parts in accompany with the growth, 24 parts of the body were measured chronologically in 259 male and 171 female Thoroughbreds born over a period from 1979 to 1982. The measurement was undertaken over a period from 300 to 1320 days of age. The following results were obtained. (1) In the early period, the height of the croup was greater than the body length. It became the same as the body length until 720 days of age, and was surpassed by the latter at 1200 days of age. (2) From 300 to 1320 days of age, the growth rate of body length was higher than that of body height at the withers, at the back, or at the croup. In this study, the growth rate of length of the breast was 65-75% of that of body length. (3) The growth in thickness of the point of the hip was more remarkable in females than in males. The growth in circumference of the forearm, cannon, gaskin and hind cannon, however, was more distinct in males than in females. (4) The highest growth rate was shown by the circumference of the breast of all the 24 parts of the body.
