EFFECT OF THE TEMPERATURE AND SALINITY ON ACTIVE METABOLISM OF MUGIL PLATANUS.

The metabolism of a fish includes three well-differentiated levels: standard metabolism, routine metabolism and active metabolism. The standard metabolism is the minimum energy required for the fish to survive, associated to rest and unfed state. The routine metabolism is the fraction of energy used by unfed fish with movement of spontaneous swimming, or routine activity. Routine metabolism is the mean rate oxygen consumption measured when precautions are taken against the fish being influenced by outside stimuli (1). The active metabolism already represents the metabolic rate in the maximum level of activity. BRETT (2) demonstrated that fast swimmer fishes can increase its metabolism up by 10 times the standard metabolism, whereas fish of colder waters increase its metabolic rate by 2 or 3 times. In addition, the swimming performance (3) was recorded as the highest position-maintaining velocity plus the fraction of the time interval of the velocity in which they became exhausted (4), i.e., the physical capacity that facilitates it to swim against a certain water direction during a certain period of time (5). This study aimed to investigate the effect of the temperature (25° C, 20° C and 15° C ) and salinity (35‰., 20‰. and 5‰ ) on active metabolism of Mugil platanus (mullet), a eurihialinic and eurithermic fishThis study aimed to investigate the effect of the temperature (25° C, 20° C and 15° C ) and salinity (35‰., 20‰. and 5‰ ) on active metabolism of Mugil platanus (mullet), a eurihialinic and eurithermic fis