The influence of weight and temperature on the routine oxygen consumption of C. macropomum , a Neotropical fish species of the family Serrasalmidae, was investigated during a constant flow respirometer. Plotted on a double logarithmic grid, oxygen consumption increases linearly with weight. Slopes of 0.64 at 25 and 30° C, and 0.78 at 35° C were obtained. Because of the significant difference in the slopes, a general value could not be provided. The metabolic rate of a 100 g fish increases from 103.7 to 191.5 and 289.7 mg O2/kg/h at 20, 25, and 30° C, respectively. At 35° C, the oxygen consumption rate decreased to 212.4 mg O2/kg/h. The metabolic rate is comparable to those of other tropical fish species. Obviously, C. macropomum is well adapted to the constant temperature conditions of its Neotropical habitats. |
