| 초록 |
This study investigated growth and hematological changes in parrotfish Oplegnathus fasciatus (~200 g/fish) reared under different total ammonia nitrogen (TAN) concentrations (0, 4, or 8 mg/L) for 6 weeks. Survival rates of parrotfish in all experimental groups did not significantly differ, as they were all ~100%. Although specific growth rate (SGR), weight gain, and daily feed intake in the high TAN concentration group (TAN8) were significantly lower than in the other two groups, there was no significant difference between the TAN4 group and the control group, (TAN0), indicating that parrotfish have a strong resistance to ammonia toxicity. As for temporal changes of the major blood components, cortisol increased as a result of stress caused by the high ammonia concentration in the TAN8 group. For this reason, the concentrations of energy sources such as glucose and total cholesterol were reduced. However, there was little difference among all experimental groups in concentrations of liver function glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT), and nutrient factors, such as total protein and albumin. |
