中文摘要：

为了探讨水体镉（Cd）污染对鱼类的生态毒理效应,在实验室条件下,测定了不同浓度Cd（0、0.36、0.73、1.09和1.46 mg/L）暴露对鲢（Hypophthalmichthys molitrix）幼鱼半致死浓度、组织（肝、鳃、肌肉）Cd累积量、相对临界游泳速度（Ucrit）、以及耗氧率（MO_2）的影响。结果显示：Cd暴露导致重金属在幼鱼组织中累积,与对照组比较,Cd在鳃和肌肉中累积量差异不显著;肝脏中累积量差异显著,暴露浓度为0.73 mg/L时肝脏中镉累积量最高。鲢幼鱼相对临界游泳速度随着Cd暴露增加显著降低,浓度为1.46 mg/L时Ucrit为对照组的69.75%。临界游泳速度与鳃和肌肉组织中镉累积量呈显著负相关,相关系数分别为-0.96（P=0.01）和-0.90（P=0.04）。Cd暴露导致鲢幼鱼耗氧代谢范围增加,暴露浓度为0.73 mg/L时耗氧代谢范围较对照组增加了19.32%。低浓度Cd暴露导致鳃和肌肉损伤,并引起鲢幼鱼游泳过程中耗氧代谢效率降低,有氧运动能力和游泳能力下降。

英文摘要：

In this investigation,the eco-toxicological effects of cadmium on the swimming performances of juvenile silver carp（ Hypophthalmichthys molitrix） were measured. Cadmium concentrations were measured in tissues（ gill,liver and muscle）. The relative critical swimming speed（ Ucrit）,as well as oxygen metabolic rate（ MO2） range were measured in juvenile silver carp after a 96 h exposure to a range of cadmium concentrations（ 0,0. 36,0. 73,1. 09 and 1. 46 mg / L）.The results showed that cadmium exposure had significant effects on the cadmium concentrations in tissues,especially,in the liver（ F = 4. 32,P = 0. 038）. Besides,cadmium exposure had significant effects on the Ucritand MO2 range. The Ucritwas 30. 25% of the control after 96 h exposure to1. 46 mg / L cadmium. The correlation coefficients of critical swimming speed and cadmium accumulation in gill and muscle tissue were negative,- 0. 96（ P = 0. 01） and 0. 90（ P = 0. 04）respectively. The metabolic range increased with the increasing of cadmium concentration. At 1. 46 mg / L of cadmium exposure,the metabolic range increased by 19. 32% than that of the control. The results indicated that cadmium exposurewould have significant effects on swimming capabilities and the metabolic rate of juvenile silver carp. Cadmium has inhibitory effect on juvenile silver carp behavior,and low Cd concentrations exposure resulted in gill and muscle damage,and caused a decrease in oxygen metabolic efficiency,aerobic capacity and swimming ability of juvenile silver carp.