The relationship between oxygen consumption, body temperature and surface area in the hatching and young chick

Abstract

There is an increase in the effective surface area of the chick at hatching and this is accompanied by an increase in the oxygen consumption so that there is little change in the oxygen uptake per square centimetre. This results in the body temperature of the chick being maintained at its prehatching level. The body temperature of the chick rises for six days after hatching. This appears to be due to the progressive replacement of the yolk with actively metabolising tissue resulting in the active mass of the bird increasing at a greater rate than the effective surface area. The oxygen consumption (ml./g./hr.) continues to rise after the body temperature becomes constant which suggests that there is an increase in the metabolic rate after hatching.