Present study showed that the multiple regression analysis of body measurements was useful for the estimation of the body proportion between the heifer and the cow in Japanese Black and Holstein cattle. Samples were obtained from the Okinawa Animal Show in 1988 and 1989.
The step forward regression with the standard partial regression coefficients of body weight on ten body parts measurements and the coefficient of determination re-adjusted for the degree of freedon (R^**2) was utilized for the present anaysis.
The coefficient of chest girth and R^**2 in heifers of Japanese Black were 0.707 and 0.856. The chest girth, thurl width, rump length and R^**2 in cows were 0.755, 0.607 and 0.924, respectively. The chest width, rump length and R^**2 of steers were 0.416, 0.301 and 0.865, respectively.
The coefficients of chest girth and R^**2 in heifers of Holstein were 0.497 and 0.965. The values of hip width, rump length, chest girth and R^**2 in cows were 0.474, 0.394, 0.371 and 0.971, respectively.
Our result suggested that the body weight was quietly correlated to the body proportion and the coefficient of body measurements against the front quarters of body proportion in the heifer more strongly reflected than in the cows.