Cooling combined with hyperoxic CO2 anesthesia is effective in improving the air exposure duration of tilapia

The Influence of Hypothermia Hibernation Combined with CO2 Anesthesia on Life and Storage Quality of Large Yellow Croaker (Pseudosciaena crocea)

We explore the feasibility of the long-term transportation of live large yellow croakers (Pseudosciaena crocea) using the combined method of CO₂ anesthesia and hypothermia hibernation, and its effect on the quality of recovered fish stored at 4 °C. Fish treated with CO₂ anesthesia at a 2 ppm/s aeration rate were cooled at 3 °C/h to hibernate survived for 36 h at 8 °C in seawater. This method resulted in better survival rates and time, and a lower operational time than hypothermia hibernation or CO₂ anesthesia methods. The results of a blood analysis indicated that the stress experienced by the fish during hibernation was mitigated, but existent after recovery. The drip loss rate of the ordinary muscle of hibernated fish was significantly different from that of the control group at 4 °C, but there was no significant difference in the pH, lactic acid content, and color during early storage. Furthermore, hibernation did not affect springiness and chewiness. Thus, the combination of CO₂ anesthesia and hibernation may improve the survival and operation efficiency of fish in long-term transportation. However, this method affects the quality of fish after long-term storage. Thus, hibernated fish should be consumed after appropriate domestication or immediately after recovery.