Redox regulation in Atlantic cod (Gadus morhua) embryos developing under normal and heat-stressed conditions

► Impacts of a 4 °C increase on redox parameters in Atlantic cod embryos were studied. ► Embryos were incubated at optimal (6 °C) or threshold (10 °C) temperatures. ► At 6 °C, developmental increases in oxidized glutathione were observed. ► At 10 °C, survival was diminished and the glutathione redox shift did not occur. ► At 10 °C, stage-specific reduced mRNA levels occurred in several key redox genes.