| 摘 要： | The swimming endurance of whiteleg shrimp （Litopenaeus vannamei, 87.66 mm±0.25 mm, 7.73 g±0.06 g） was exam-ined at various concentrations of dissolved oxygen （DO, 1.9, 3.8, 6.8 and 13.6mgL-1） in a swimming channel against one of the fiveflow velocities （vb v2, v3, v4 and vs）. Metabolite contents in the plasma, hepatopancreas and pleopods muscle of the shrimp werequantified before and after swimming fatigue. The results revealed that the swimming speed and DO concentration were significantfactors that affected the swimming endurance ofL. vannamei. The relationship between swimming endurance and swimming speedat various DO concentrations can be described by the power model （vtb= a）. The relationship between DO concentration （mgL-l） e 9000and the swimming ability index （SAI）, defined as SAI= ∫9000vdt （cm）, can be described as SAI=27.947DO0.137 （R2=0.9312）. Thelevel of DO concentration directly affected the physiology of shrimp, and exposure to low concentrations of DO led to the increasesin lactate and energetic substrate content in the shrimp. In responding to the low DO concentration at 1.9 mg L-1 and the swimmingstress, L. vannamei exhibited a mix of aerobic and anaerobic metabolism to satisfy the energetic demand, mainly characterized by theutilization of total protein and glycogen and the production of lactate and glucose. Fatigue from swimming led to severe loss ofplasma triglyceride at Vl, v2, and v3 with 1.9mgL-1DO, and at V1 with 3.8, 6.8 and 13.6mgL-1 DO, whereas the plasma glucose con-tent increased significantly at v3, v4 and v5 with 3.8 and 6.8mgL-1 DO, and at v5 with 13.6mgL-1 DO. The plasma total protein andhepatopancreas glycogen were highly depleted in shrimp by swimming fatigue at various DO concentrations, whereas the plasmalactate accumulated at high levels after swimming fatigue at different velocities. These results were of particular value to under-standing the locomotory ability of whiteleg shrimp and its physiological changes, further contributing to the improvement of captureand rearing technique.
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