Effects of acute and chronic hypoxia on the locomotion and enzyme of energy metabolism in Chinese shrimp Fenneropenaeus chinensis

To characterize the locomotor behaviors and their relation with physiological regulation in Chinese shrimp Fenneropenaeus chinensis, animals were held at approximately 6.0 (normoxia), 4.5, and 3.0 mg L(-1)dissolved oxygen (DO) for 1 day (acute) and 15 days (chronic), after which the swimming and tail-flipping abilities, and the activities of key enzymes involved in anaerobic and aerobic metabolism in hepatopancreas and pleopod and abdominal muscles were determined. Results showed that hepatopancreas was preferentially powered compared with pleopod and abdominal muscles during hypoxia. Physiological differences in muscles resulted in locomotion differences. F .chinensis presented reduced reliance on anaerobic glycolysis to conserve energy during chronic hypoxia at 3.0 mg L-1DO, but this physiological regulation reduce the survival of shrimp in the wild due to a reduction in tail-flipping. These findings suggested that when assessing the survival strategy of shrimp during hypoxia, both physiological regulation and behavioral changes should be considered.