| In this study, effects of environmental endocrine disruptors NP and TBT on growth ratio, gonad differentiation and organization structure on M.rosenbergii were studied by morphologic observation and continuous histological sections, in order to explore the toxicity of environmental pollution on the economy crustaceans, and reproductive damage, etc. By doing so, an evaluation system about pollution on crustacean can be established, and protection measures on fishery resources and aquatic ecosystems can be also suggested. The main results as followings:1.At water temperature 24～30℃, The mortality of the juvenile or adult giant freshwater prawn M.rosenbergii was noted at 96h. The test showed that the 96hLC50 of the juvenile or adult giant freshwater prawn M.rosenbergii were 1350 and 2925μg/L, and the safe concentration of them were 135 and 292.5μg/L. Gill, liver and pancreas, and stomach of the adult giant freshwater prawn M.rosenbergii were destroded seriosly treated by NP (10,30,90 and 270μg/L) for 28 days.①Blurred gill lobe structures, thickened respiratory epithelial cells and the damaged epithelial cells were observed in gill of NP treated group (concentration less than 30μg/L), and brown sediment were found at the base of the gill leaves. However, significant increased number of epithelial cells and blood lymphocytes were observed in the gill of NP treated group (concentration more than 90μg/L), and severe diffuse necrosis, necrosis of tissue scattered everywhere at the end of the gill leaves;②When the concentration is less than 90μg/L, the liver and pancreas cell vacuoles phenomenon, some individuals appear hepatopancreas cell lysis phenomenon, when the NP concentration of 270μg/L, the liver and pancreas cells vacuolization serious, fuzzy boundaries and cell lysis, liver and small tubular atrophy, reduced liver nuclei;③Concentration less than 90μg/L, the stomach cuticle thickens, the concentration of 270μg/L, the vague outline of epithelial tissue, a large number of epithelial cells necrotic.2. Effects of NP (5μg/L, 15μg/L, 45μg/L and 135μg/L) on body length, weight and sexual rate were studied at the early stage of growth on giant freshwater prawn M.rosenbergii. There were no significant differences (P﹥0.05) in body length and weigh between the control and the NP treatment groups exposed for 10 to 15 days at water temperature 24～30℃. However, obvious decresed body length and weigh were found in giant freshwater prawn treated by NP (except 5μg / L) for more than 20 days (P <0.05). No significant difference in sexual rate was observed between the control and the NP treatment groups, while the number of gonad undeveloped increased with the concentration of NP. There were no intersexul gonad in NP treatment groups.3.At water temperature 24～30℃, The mortality of the juvenile or adult giant freshwater prawn M.rosenbergii is noted at 96h. The test shows that the 96hLC50 of the juvenile or adult giant freshwater prawn M.rosenbergii were 51,376μg/L;The safe concentration of the juvenile or adult giant freshwater prawn M.rosenbergii were 5.1,37.6μg/L.the adult giant freshwater prawn M.rosenbergii of the experimental groups(2,8,32μg/L). Gill, liver and pancreas and stomach three kinds of organizations have produced anomalies, TBT concentrations below 8μg/L, the treatment group of gill epithelial cells showed swelling, support cells in the nucleus contraction, blood cavity blood cell aggregation; liver and pancreas cells showed vacuolization; stomach appeared thickened cuticle. TBT was higher than 32μg/L treatment groups the blood gill cavity blood cell swelling, shorter gill lobe atrophy, the base of the common epithelial cells increased significantly, epithelial membrane shrinkage, thickening of the gill filaments; liver and pancreas of a serious degree of vacuolization, nucleus disappeared, and the emergence of necrosis; gastric epithelium blurring the cuticle, epithelial cells were detached.4.At water temperature 24～30℃, The concentration of 0μg/L, 1.25μg/L, 2.5μg/L, and 5μg/L of TBT exposure concentration of 30d, the 10d, 20d, 25d, 30d time, 1.25μg/L and 2.5μg/L treated group weight, body length was significantly lower than the control group (P <0.05), 5μg/LNP treated group body weight, body length compared with the control group, with significant differences (P <0.01). However, TBT on giant freshwater prawn M.rosenbergii did not affect the sex ratio, can not determine the sex of the gonad of juvenile prawn M.rosenbergii in undeveloped state, did not find two individuals gonads.
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