Effects of Temperature Reduction and MS‐222 on Water Quality and Blood Biochemistry in Simulated Transport Experiment of Largemouth Bronze Gudgeon, Coreius guichenoti

Abstract

AbstractThe effects of temperature reduction, MS‐222 (3‐aminobenzoic acid ethyl ester methanesulfonate) anesthesia and the combination of these factors on water quality and the blood biochemistry of the largemouth bronze gudgeon, Coreius guichenoti, a rare, endangered, and valuable fish in the upper Yangtze River, were investigated before and after simulated long‐term transport. The results showed that transport caused deterioration of water quality and elevated the concentrations of plasma cortisol (2–3.5 times) and plasma lactate (1.33–2.5 times) in C. guichenoti. Temperature reduction was found to play a major role in improving the water quality by reducing total ammonia nitrogen and oxygen consumption, while MS‐222 anesthesia mainly inhibited the activity of transported C. guichenoti and suppressed the increases in plasma lactate and alanine aminotransferase. Some interactions were observed between anesthesia and temperature reduction during C. guichenoti transportation regarding improving the water quality and reducing the physiological stress. The results suggest that during the long‐term transportation of C. guichenoti, the combined use of temperature reduction and MS‐222 is most preferable, followed by the use of temperature reduction alone or MS‐222 at a relatively high temperature. These data provide useful information regarding the transport and physiological response of C. guichenoti as well as other related stresses in this fish.