The inheritance of growth and form in the mouse. V. Allometric growth.

A complete diallel cross, including inbreds and reciprocals, was made among six inbred lines of mice. Body weight, tail length and tail width were measured at ages of 1 through 12 weeks. The parameters of 4 longitudinal allometric relations, y = bxa, were determined for each mouse: tail length vs. body weight for weight for weeks 1 through 9 and for weeks 1 through 12, and tail width vs. body weight for the same periods. The estimated value of a was taken as one variable and the value of log y corresponding to a weight of 12 g or 15 g for 9 or 12 pairs of measurements was taken as the other. The allometric equation appears to provide a satisfactory empirical description of the relative growth of tail length and width vs. body weight. The diallel analysis suggests a low heritability for a for both sexes and both periods and an intermediate heritability for the location parameters.