高锰酸钾对中华绒螯蟹的毒性作用及持续效应

Toxicity and Continuous Effects of Potassium Permanganate to Chinese Mitten Handed Crab Eriocheir sinensis

在水温15~20℃下,将体质量(7.2±1.5)g的中华绒螯蟹(Eriocheir sinensis)早熟蟹和体质量(5.2±1.3)g幼蟹置于50 L的塑料水箱中,高锰酸钾浓度分别为32 mg·L^(-1)、64 mg·L^(-1)、128 mg·L^(-1)、256 mg·L^(-1)、512 mg·L^(-1)、1024 mg·L^(-1)、2048 mg·L^(-1)和16 mg·L^(-1)、32 mg·L^(-1)、64 mg·L^(-1)、128 mg·L^(-1)中,采用静水生物毒性实验法,研究高锰酸钾对中华绒螯蟹的毒性。毒性实验观察96 h后,将中华绒螯蟹投入清水中继续饲养30 d,研究高锰酸钾对中华绒螯蟹生长的影响。结果显示,高锰酸钾对早熟蟹和幼蟹的96 h半致死浓度(LC_(50))分别为106.64 mg·L^(-1)和53.81 mg·L^(-1),安全浓度(SC)分别为10.66 mg·L^(-1)和5.38 mg·L^(-1);清水条件下,浸浴在高于16 mg·L^(-1)高锰酸钾中所存活的幼蟹在4 d后死亡,浸浴在安全浓度下的早熟蟹和幼蟹依然存活,且蜕壳率分别为20%、6.67%,而未经高锰酸钾处理的对照组早熟蟹和幼蟹的蜕壳率则为13.33%、43.33%;幼蟹的蜕壳率和体质量显著大于实验组幼蟹(P<0.05)。结果表明当高锰酸钾浓度到达一定程度后,个体损伤无法逆转,虽然安全浓度对幼蟹死亡率没有影响,但阻碍其生长发育。

Precocious juvenile Chinese mitten handed crab(Eriocheir sinensis)with body weight of(7.2±1.5)g and normal juvenile Chinese mitten crab with body weight of(5.2±1.3)g were placed in a 50 L plastic water tank and exposed to potassium permanganate at concentrations of 32 mg·L^(-1),64 mg·L^(-1),128 mg·L^(-1),256 mg·L^(-1),512 mg·L^(-1),1,024 mg·L^(-1),2,048 mg·L^(-1)and 16 mg·L^(-1),32 mg·L^(-1),64 mg·L^(-1),128 mg·L^(-1),respectively,at water temperature of 15~20℃by a hydrostatic biological toxicity test method to explore the effects of potassium permanganate on Chinese mitten handed crab toxicity.After 96 h of toxicity test,Chinese mitten handed crab were put into clean water and kept for 30 d to explore the effect of potassium permanganate on the growth of Chinese mitten handed crab.The results showed that the 96 h LC_(50) were 106.64 mg·L^(-1)in the precocious juveniles with safety concentration(SC)of 10.66 mg·L^(-1)and 53.81 mg·L^(-1)in normal juvenile crab with SC of 5.38 mg·L^(-1).In the clear water,the juvenile crab exposed to more than 16 mg·L^(-1)potassium permanganate died in four days,and the precocious crabs and juvenile crabs(experimental group)bathed in a safe concentration were still survival,with molting rate of 20%and 6.67%,respectively.However,the precocious crabs and juvenile crabs without potassium permanganate treatment had molting rates of 13.33%and 43.33%,significantly higher molting rates and body weight in the juvenile crab than the juvenile crab in the test groups(P<0.05),indicating that when the potassium permanganate concentration reaches a certain level,the individual damage was reversed.The growth and development of juvenile crab were hindered,although the mortality of juvenile crab was not affected under the safe concentration.The findings enriched the research content of the disinfectant application in aquaculture by exploring the continuous effect of potassium permanganate on the toxic effects of Chinese mitten handed crab.