Cardiorespiratory and thermal responses to hypercapnia in chickens exposed to CO 2 during embryonic development.

•CO2 during embryonic development does not change ventilation in 10 days chicks under room air conditions, regardless of sex.•Hypercapnic ventilatory response is decreased by pre-exposure to 1 % CO2 during embryonic development, especially in in 10 days male chicks.•CO2 during the beginning of embryonic development on the embryo did not cause changes in body temperature in chicks.•Embryonic CO2 exposure does not change blood pressure and heart in chicks.•Post-hatch effects of embryonic exposure to CO2 is sex-dependent.