Effect of operculum dissection tagging on oxygen consumption and hematological response of Korean rockfish Sebastes schlegelii

Abstract

Oxygen consumption and hematological response of the juvenile Korean rockfish, Sebastes shlegelii (mean body weight 45 g) were investigated under three different operculum dissection tagging: no dissection (control), one side (OS) and both sides (BS) dissection. Oxygen consumption rate (OCR) of fish was measured with an interval of 5 minutes for 24 hours using a continuous flow-through respirometer under 15, 20, and 25℃, respectively. In each group three replicates were set up and 45 fish were totally involved. Hematological responses such as cortisol, hemoglobin, hematocrit, and glucose were measured at 1, 6, 12, 24 and 48 hours of each group after tagging. The blood of fish sampled 5 fish of each time. The OCRs increased with increasing water temperature under all groups (P < 0.001). The OCRs of OS group were significantly (P < 0.05) higher than those of control and BS groups except 15℃. In case of 15℃, the OCR of BS group was significantly (P < 0.05) lower than that of OS group, but there was no difference between the control and BS. The concentrations of hemoglobin, hematocrit and glucose in OS and BS groups were significantly (P < 0.05) higher than that of control after 1 hour of tagging, but there were no differences among the groups in the other times. The significant higher concentration of cortisol than control showed after 1 hour tagging in BS, and 1 and 6 hours tagging in OS group. Based on the results,sides (BS) dissection. Oxygen consumption rate (OCR) of fish was measured with an interval of 5 minutes for 24 hours using a continuous flow-through respirometer under 15, 20, and 25℃, respectively. In each group three replicates were set up and 45 fish were totally involved. Hematological responses such as cortisol, hemoglobin, hematocrit, and glucose were measured at 1, 6, 12, 24 and 48 hours of each group after tagging. The blood of fish sampled 5 fish of each time. The OCRs increased with increasing water temperature under all groups (P < 0.001). The OCRs of OS group were significantly (P < 0.05) higher than those of control and BS groups except 15℃. In case of 15℃, the OCR of BS group was significantly (P < 0.05) lower than that of OS group, but there was no difference between the control and BS. The concentrations of hemoglobin, hematocrit and glucose in OS and BS groups were significantly (P < 0.05) higher than that of control after 1 hour of tagging, but there were no differences among the groups in the other times. The significant higher concentration of cortisol than control showed after 1 hour tagging in BS, and 1 and 6 hours tagging in OS group. Based on the results,