Hagfish Eptatretus burgeri is classified as a agnathans and has many different physiological properties compared with vertebrates. In this study, we examined effects of water temperature and salinity on blood properties and oxygen consumption in hagfish. In the experiment of water temperature change, hematocrit (Ht), red blood cell (RBC) and glucose of hagfish blood revealed the lowest values at 15. Oxygen ℃ consumption of hagfish had significantly increased with rising water temperature, and the increasing rate was twice as much when the temperature was manipulated every 5. Also, oxygen consumption during ℃ the night time (a short photoperiod) was significantly higher than that of the daytime. Q10 level was 3.50 in the light period and 3.92 in the dark period. No significant change in plasma glucose level was showned in changing salinity from 30 psu to 22 psu, while it had rapidly increased at 20 psu (13.7±4.0 mg/dL) and thereafter all hagfish were dead at 18 psu. However, osmolarity, Na+, K+ and Cl-levels had significantly decreased when salinity decreased. This results are expected to develop the artificial rearing techniques of natural hagfish.

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Aquaculture production of Korean rockfish Sebastes schlegeli has been continuously increased from 2000s and the fish has become the second most important mariculture fish in Korea. However, there are some environmental problems in aquaculture of Korean rockfish recently. In this regards, stress responses to high water temperature was examined via oxygen consumption, blood physiological parameter and endocrinological method. Oxygen consumption of Korean rockfish had significantly increased with rising water temperature. And oxygen consumption during the light time was no different with the dark time. The levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) showed no difference until 27 , but it had rapidly increased at 30 . Moreover high water temperature affected to increase in ℃ ℃ plasma glucose and cortisol levels.

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