Toxicity Of Heavy Metals In Cyprinus Carpio, Carassius Auratus Pengzenensis And Residues Of Antibiotics In Trionyx Sinensis

The main objective of this paper is to use Cu,Zn,Cd and oxytetracycline, norfloxacin as experimental toxicants and Cyprinus carpio,Carassius auratus Pengzenensis,Trionyx sinensisas as experimental creature, studied the toxicity of copper,zinc,cadmium to the larval carps; accumulations of copper,zinc in the larval carps. The results showed that toxicities of three heavy metals were in the sequence of Cu>Cd>Zn for the larval carps,the 96th lethal concentration and safe concentration of Cu,Zn,Cd were 0.2mg/L,0.02mg/L;7.05mg/L,0.70mg/L;2.51mg/L,0.25mg/L.The results of accumulation indicated that copper,zinc mainly accumulated in gill,liver and kidney. There are some copper,zinc in muscle and bone.The degree of accumulation increase by the growth of exposed time.Then it reached homeostasis at last,some copper and zinc was transferred and discharged.Secondly,the results showed that accumulation of copper was related to metallic species and con-centration,and as well as fish tissues.The interaction became more significant with the increase of the metals;the accumulation of the copper increased in kidney,brain and gill in the mixture-metal interaction,but the metal mixture could not affect the accumulation of Cu in the muscle.The other metals could not change the accumulation order of the copper in the tissues of Carassius auratus Pengzenensis,the accumulation order of the Cu in the fish tissues was kidney>brain>gill>muscle.Finally,Trionyx sinensis were injected intramusclularly respectively by different doses of oxytetracycline and norfloxacin once one day for five days at water temperature of (25.5±1)°C.The three tissues,i.e.liver,kidney and muscle,were analyzed at hour 24,72,120 and 240 after withdraw medication.The result indicated that norfloxacin could be only detected in the liver and muscle at 72 and 144 hour post-dosing,but other samples were not noted.The experiment result also showed that residue levels of oxytetracycline were highest in liver,kidney secondly,lowest in muscle. OTC levels in kidney and muscle reached the maximum at day 3 post-dosing; but at day 6 post-dosing in liver. OTC levels in the liver decreased rapidly after treatment,whereas in the muscle and kidney,level peak initially before decreasing slowly with time.OTC levels were very low (0.35mg/kg in liver 0.25mg/kg in muscle) at day 10 post-dosing.However,OTC levels stayed high (2.18mg/kg) in kidney.So concluded that the muscle had the lowest OTC residue among the soft turtle tissues.