the first week and high EST (38.9°C) during the third week
of incubation on embryo development, hatchability, and posthatch performance. Eggs in the control group were incubated at a constant EST of 37.8°C. Because parent stock age is an important factor in embryo development and hatchability (Gladys et al., 2000), the trial was performed twice with eggs of parent stock of different ages.
Beside effects of eggshell temperature on embryo development and hatchability, posthatch performance was also determined
in chicks housed at different temperatures (HT).