THE DAILY TOTAL METABOLISM AND SPECIFIC DYNAMIC ACTION IN THE SOUTHERN CATFISH (SILURUS MERIDION ALIS)

The daily total metabolism of 91 juveniles weighing 8.49-151.0 g were measured with closed respirometers at 15, 20, 25, and 30℃. The fish were fed four ration levels from starvation to 4% B. W. /day. The ratio of total metabolism to resting metabolism increased with increasing ration level and decreasing temperature. The ratio ranged from 1.076 to 3.066. The metabolic cost per unit body weight gain, calculated from the linear relationship between metabolism and growth, was 2288.2 J/g. The specific dynamic action (SDA), expressed as a percentage of food energy, was independent of temperature and body weight, and was 20.18%.