The Importance of the Time Element in the Determination of the Respiratory Metabolism of Fishes

Abstract

Data obtained from many expts. on the rate of respiratory metabolism of Fundulus parvi- pinnis indicate that after approximately 24 hrs. under experimental conditions these fishes attain a metabolic rate that is lower and more constant than that of the initial period. This final rate may be maintained for several days and this "normal" metabolism is defined as the value obtained at any given constant temp. within the normal temperature range and which is maintained for at least 12 hrs. at approximately the same level. The time required to reach a normal level probably varies in different species of fishes. The continuous flow method was used, and the O determined by the Winkler method.