Despite the recognition that increased suspended solids is harmful to aquatic organisms, studies on the responses of them to suspended solids are limited. The present study determined ecotoxicology risk of suspended solids by evaluating the effects of suspended solids on survival rate, weight gain rate, RNA/DNA ratio and DNA damage of Marsupenaeus japonicus postlarvae. The results suggest that suspended solids have little influence on postlarvae in low concentration groups(＜500 mg/L), while in high concentration groups (≥500 mg/L), the suspended solids could increase the survival rate of the postlarvae due to lower cannibal rate, but decrease the weight gain rate and RNA/DNA ratio of the postlarvae. And weight gain rate has significant positive relationship with RNA/DNA ratio. Although DNA damage parameters such as comet cell rate, tail length and tail moment clearly increased in high concentration groups (≥ 500 mg/L), tail length and tail moment were more sensitive as comet indicators of DNA damage than comet cell rate. These results suggest that RNA/DNA ratio and DNA damage parameters are effective biomarkers for assessing the effects of suspended solids on Marsupenaeus japonicus postlarvae.%以日本囊对虾(Marsupenaeus japonicus)仔虾为受试生物,研究不同悬沙浓度(0、l0、50、100、500和1 000 mg/L)下仔虾的存活率、增重率、RNA/DNA比率变化和DNA损伤情况,探讨悬沙对仔虾的影响.结果表明,低浓度悬沙(＜500 mg/L)对仔虾的存活率、增重率、RNA/DNA比率和DNA损伤指标无显著影响.高浓度悬沙(≥500 mg/L)为仔虾生长蜕皮提供隐蔽场所,减少自残,但在提高存活率的同时,影响仔虾摄食,表现为仔虾的增重率和RNA/DNA比率与对照组相比显著下降(P＜0.05),且增重率和RNA/DNA比率之间具有显著的正相关性(P＜0.05).在高浓度悬沙组(≥500 mg/L)中,作为DNA损伤指标,彗星细胞拖尾率、尾长和尾矩与对照组相比均显著增加(P＜0.05),但不同的指标灵敏度不同,尾长和尾矩灵敏度较拖尾率更高.结论认为,RNA/DNA比率和DNA损伤指标能够有效评估悬沙对仔虾生长的影响.
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