Influence of salinity, temperature and body weight on oxygen consumption and ammonia excretion of Pleuronectes yokohama juvenile

Abstract:

The effects of salinity (8,14,20,26,32), temperature (10,15,20℃) and body weight (6 groups) on oxygen consumption rate and ammonia excretion rate of Pleuronectes yokohama juvenile were studied by means of closed breathing experimental method in this study. The results showed that when salinity ranged between 8 and 32, the oxygen consumption rate and ammonia excretion rate were significantly decreased with salinity decline. While temperature was between 10 and 20℃, the oxygen consumption rate and ammonia excretion rate were significantly increased with the increase of temperature. In addition, the oxygen consumption rate and ammonia excretion rate decreased with the increase in weight. The O/N ratio decreased with the increase of salinity and the decrease of temperature, and it showed the O/N ratio ranged from 44.441 to 12.278 and 13.446 to 17.631 respectively. The average Q₁₀ values at these temperature were 1.545 and 2.018 respectively, while no significant differences were found in O/N ratio among different body weight. The energy sources of P. yokohama under the experiment conditions were mostly fat and protein with different ratios, only in the group of salinity 8 the energy sources were fat and sugar.