Influence of Illumination Oscillations on Growth and Energetics of the Goldfish Carassius auratus

Periodic oscillations of illumination exert a positive, rather than negative, effect on goldfish growth and energetics. In a variable light regime, the fishes grow at a higher rate, have decreased oxygen and food requirements, improve the utilization of consumed food for growth, and decrease the oxygen expenditure per increment of unit body mass. The goldfish reactions to the frequency of illumination oscillation and the succession of the stationary light regime by the oscillatory regime were described.