Transport and Recovery of Turbot (Scophthalmus maximus) Sedated with MS-222 and Eugenol: Effects on Intermediary Metabolism and Osmoregulation

SIMPLE SUMMARY: The waterless transportation of live fish is considered to be a green and economic solution to achieve a high survival rate. However, the effects of cold domestication and the environment after leaving the water are prone to cause stress in fish. In this experiment, the turbots were anesthetized with 40 mg/L MS-222 and 20 mg/L eugenol solution. Then, turbots were cooled to dormancy, followed by waterless transport for 18 h. The results of blood physiological indices indicated that the MS-222 and eugenol could reduce the stress on turbot during cooling and simulated waterless transport. ABSTRACT: This study focused on the anesthetic waterless keep-alive transport technique for turbot. MS-222 and eugenol were used to anesthetize turbot and then the waterless keep-alive transport was conducted. The blood physiological changes and flesh quality changes of turbot were evaluated after cooling and during the simulated waterless transport. The results show that the temperature lowered from 13 to 2 °C, resulting in a decrease in moisture, fat and protein contents of all samples. Compared to the control turbot, the turbots treated with MS-222 and eugenol presented higher pH and glycogen content. During the simulated waterless transport, the pH, ATP and glycogen contents in MS-222- and eugenol-treated turbots decreased and the IMP and lactate levels increased. For the blood biochemical indices, blood glucose, cortisol and urea nitrogen increased with the increase in transport time in MS-222- and eugenol-treated turbots. At sampling time, the changes in blood physiological indices were significantly higher in the control samples than those in the MS-222- and eugenol-treated samples. The results indicate that the turbot samples treated with MS-222 or eugenol could reduce stress during cooling and simulated waterless transport.