Abstract

BALCıOğLU, M.S.; KıZıLKAYA, K.; YOLCU, H.İ.  and  KARABAğ, K.. Analysis of growth characteristics in short-term divergently selected Japanese quail. S. Afr. j. anim. sci. [online]. 2005, vol.35, n.2, pp.83-89. ISSN 2221-4062.

This study was carried out to examine the effect of short-term selection for 5-weeks of age body weight in divergent lines of Japanese quail. Growth curves for both sexes within each selection group resembled the general sigmoid shape of a typical growth curve. Gompertz model curves and the observed growth curves were very similar. In both males and females the parameter estimates of the Gompertz growth curve were obtained with a high determination coefficient (0.9898 > R² > 0.9840). Sex differences in asymptotic weight were found to be significant across lines. Similarly, in both sexes a significant divergent selection effect was determined for parameter A. The growth rate in all the Japanese quail lines was significantly higher in males than in females. There was also a significant increase in growth rate of the females selected for increased 5-week body weight over the control females, as well as a significant decline in growth rate of males selected for decreased 5-week body weight compared to the unselected control group.

Keywords : Gompertz model; growth curve; asymmetric response; growth rate.

        · text in English     · English ( pdf )