Adaptation of chickens to extremes of temperatures

Experiments were designed to study in chickens:

(1) the relationship of rearing temperature to the ability to resist extremes of temperature,

(2) the relationship of the ability to resist one extreme of temperature to the ability to resist the opposite extreme,

(3) the relationship of adrenal size and ascorbic acid content to rearing temperatures and the ability to resist temperature extremes, and

(4) the effect of a tranquilizer upon the development of resistance to extremes of temperature.