| Currently, water pollution in aquaculture increasingly sticks out, the pesticidespollution in aquaculture attracted people’s attention. Endosulfan is an organochlorinepesticide, lots of studies had been conducted to investigate the toxicity of endosulfan,but there is no national sholars foucesd on the toxicity of endosulfan to M. rosenbergii.Therefore, a static study was conducted to investigate the acute toxicity of endosulfanto different life stage of M.rosenbergii; meanwhile the chronic toxicity of endsouflanon M. rosenbergii was conducted using the method of tissue sections; lastly, arecovery test was conduted. Results were followed:1. Acute toxicity of endosulfan to zoae and postlarvae of M.rosenbergiiThe24h,48hLC50and safe concentration of endosulfan for Z5, Z7, Z9werefollowed as2.09,0.39and0.004mg/L；2.99,0.84and0.02mg/L；4.43,2.00and0.12mg/L;24h,48h,72h,96hLC50for postlarvae were5.48,1.85,0.62and0.47mg/L,respectively; safe concentration were followed as SCZ5<SCZ7<SC仔虾<SCZ9. Therewere a significant increase on Na~+/K~+-ATPase activity when postlarve exposed toendoufan0.01-0.26mg/L (P<0.05), but there was no remarkable effect on ACP andAKP activities in postlarvae.2. Acute toxicity of organcholine insecticide endosulfan to M.rosenbergii96h LC50of endosulfan for prawns1.5,4and7cm-long were1.52,4.53, and6.09mg/L, respectively.AKP and ACP activities in hepatopancreas of prawn1.5and7cm long didn’tshow concentration-respone relationship, however, ACP activity of hepatopancreas7cm long exposed to endosulfan0.12and199.89mg/L were lower than control group(P<0.05); ACP and AKP activities in hepantopancreas of prawns4cm long were lowerthan control group.AChE activities in hepatopancreas of praws1.5,4and7cm long were allsignificantly lower than control (P<0.01); POD activities in hepatopancreas of prawn1.5cm long from treatment0.12mg/L and0.43mg/L were significantly lower than control (P<0.05); POD activities in the hepatopancreas of prawn4cm long whencompared with control were reduced by64.7%,78.1%,98.5%,56.1%,67.0%,59.3%and48.0%, respectively; POD activities in the hepatopancreas of prawn7cm wererespective47.2%,39.7%,22.0%,60.9%,9.9%,1.3%and58.4%of control group.Na~+/K~+-ATPase in the hepatopancreas of prawn1.5cm long were lower thancontrol exposed to endosulfan0.01mg/L,0.43mg/L,1.51mg/L,5.31mg/L and18.62mg/L; Na~+/K~+-ATPase in prawn7cm long were significantly reduced by49.3%,73.6%,40.3%,37.4%,6.1%and46.4%.3. Chronic toxicity and histopathological studies with endosulfan in freshwaterprawn Macrobrochuium rosenbergiiThe survivals of prawns in each treatment were decreased as exposure ofendosulfan concentration increased; however, there was no significant relationship ongrowth rate (weight gain and length gain) compared with control group (P>0.05).After50d, LSZ activities in prawns were extremely significant lower thancontrol (P<0.01); ACP activity in prawns of treatment0.06mg/L was the most lowest;AKP activity in prawns of treatment0.05mg/L was significantly higher than control(P<0.01); MDA concentrations were respective121%,134%,99%,80%,106%and44%of control group; GPX activities in prawns exposed to endosulfan0.05~0.16mg/L were induced, while GPX activities were decreased.Significant structural alterations of hepatopancrea tubules were observed inM.rosenbergii exposed to0.05-0.60mg/L endosulfan, including swelling and fusion ofbasal laminae, tubular necrosis lesion, separation of necrotic cells of thehepatopancreas from basal laminae, hemoctic infiltration in interstitial sinuses,appearance of eosinophilic materials and brown granules.4Recovery test of M.rosenbergii after long term exposure of endosulfanAfter60d of expoure, total ensoulfan concentration in the muscle samples fromprawns exposed to0.25mg/L,1.00mg/L and4.00mg/L were1.57pg/g,1.72pg/g and1.95pg/g, respectively, the mean of bioconcentration factor was2.83. Expoused toclean water for7d, total ensoulfan concentration in the muscle samples from prawnswere1.84pg/g,1.84pg/g and1.95pg/g, respectively; After7d fed in phenobarbitalsolutions, total ensoulfan concentration in the muscle samples from prawns were1.38pg/g and1.73pg/g. After30d fed in clean water, no endosulfan had been detectable inthe muscle samples. Meanwhile, no endoslulfan sulfate had been detected throughoutall the samples. |
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