GROWTH CURVE PARAMETERS OF LINES OF JAPANESE-QUAIL (COTURNIX-COTURNIX-JAPONICA), UNSELECTED AND SELECTED FOR 4-WEEK BODY-WEIGHT

This study was carried out to estimate growth curves of control and se lection lines which was selected for higher 4-week body weight for fiv e generations and to compare three nonlinear growth models (Gompertz, Bertalanffy and Logistic) in terms of fitting to quail data, and ident ify genetic and environmental effects on growth curve parameters. Body weights from hatch to sexual maturity were measured twice a week to s tudy growth pattern of quail. Gompertz, Bertalanffy and Logistic model s provide a better description of growth curve of quail summarizing ag e-weight data into the three growth curve parameters. Although all gro wth models used fit the quail data well, Gompertz was the best model. Line and sex were generally significant effects on growth curve parame ters. Genetic variation in asymptotic weight were observed. The high c orrelation among the same growth curve parameters (say A) from differe nt models show that the parameters tend to measure similar characteris tics of growth.