The influence of elevated environmental temperature and nutrient intake on thyroid status and hepatic enzyme activities in immature male chicks.

1. Increases in hepatic ATP citrate lyase specific activity and in serum thyroxine levels were observed in immature chicks in response to either controlled food and water intakes at 22 degrees C, or an elevation in environmental temperature to 30 degrees C. Hepatic phosphofructokinase specific activity was reduced at the higher temperature. 2. Over a 4-week experimental period thyroid function and hepatic enzyme activities adapted to the controlled nutrient intake but not to the temperature stressor.