t was age and an independent variable (d); Wt was body weight or body component weight at t days of age and a dependent variable (g); Wm was parameter of mature body weight or body component weight; B was parameter of the growth rate for the body weight or body component weight before maturity; and t* was age parameter of body weight or body component weight reaching maximal growth rate. Among these, the weight at the inflection point was 0.368Wm (i.e., Wm/e); the age at the inflection point was t*; and the maximal daily gain was Wm _ B/e