Comparison of Oxygen Consumption of Larval and Juvenile Carp Determined by Three Different Methods

Abstract

The oxygen consumption of carp of 0.0021-3.5 g (1 to 79 days old after hatching) was determined at 25°C by three different methods. Oxygen consumption in vivo of intact fish (M_{in vivo}) was determined by the semiclosed method and the constant flow method. Oxygen consumption in vitro of minced whole body (M_{in vitro}) was determined by manometry.
The relationship between oxygen consumption of an individual fish (M in μl O₂•min^-1) and body mass (W in g) was expressed by the equation M=aW^b. Mass exponent “b” was 0.831, and was identical for the three methods. The light condition had an effect on oxygen consumption in the semi-closed method, but not in the constant flow method. The value of “a” was 5.71 in the semi-closed method in the light, 4.56 both in the semi-closed method in the dark and in the constant flow method in the three light conditions, and 2.70 in the manometry method. The difference in the value of “a” among the different methods of respirometry is thought to be due to the difference of activity of fish.