水体盐度对雌性三疣梭子蟹生长、卵巢发育、渗透压调节、代谢和抗氧化能力的影响

Effects of water salinity on the growth, ovarian development, osmoregulation,metabolism and antioxidant capacity of adult female swimming crab(Portunus trituberculatus)

为研究长期盐度适应对雌性三疣梭子蟹生长、卵巢发育、渗透压调节、代谢和抗氧化能力的影响,本实验设置了不同盐度(10、15、20和25)的水体,对生殖蜕壳后三疣梭子蟹雌体进行60 d的盐度适应实验。结果显示:(1)雌蟹的成活率、增重率、特定生长率和性腺指数随水体盐度的升高而显著上升。(2)血清渗透压、Na^+、Cl^–、Ca^2+、Mg^2+、大部分游离氨基酸和总游离氨基酸含量及后鳃Na^+/K^+-ATP酶活性均随水体盐度的升高而显著上升。(3)血清中葡萄糖和肝胰腺乳酸含量随水体盐度的升高而显著降低,而血清中的尿素氮、尿酸及肝胰腺中的尿酸含量均随水体盐度的升高而显著上升;肝胰腺中的甘油三酯、总胆固醇和尿素氮含量均在20和25盐度组较高。(4)10盐度组血清和肝胰腺中的总超氧化物歧化酶活性显著低于其他组,而血清中的总抗氧化能力、谷胱甘肽过氧化物酶、γ-谷氨酰转肽酶、血蓝蛋白和肝胰腺中的谷胱甘肽过氧化物酶、丙二醛水平均在10盐度组最高。研究表明,水体盐度升高可促进三疣梭子蟹生长和卵巢发育;在20和25盐度条件下,雌蟹机体的代谢水平和氧化胁迫较低。

In order to investigate the effects of long-term salinity adaptation on growth,ovarian development,osmoregulation,metabolism and antioxidant capacity of adult female swimming crab(Portunus trituberculatus),adult female P.trituberculatus post puberty molt was subjected to four water salinities(10,15,20 and 25)for 60 days.The results showed as follows:The survival rate,weight gain rate,specific growth rate and gonadosomatic index of female crabs increased significantly with increasing water salinity.The serum osmolality and the contents of Na^+,Cl^-,Ca^2+,Mg^2+and major free amino acids,and total free amino acids in the serum,as well as the posterior gills Na^+/K^+-ATPase activity showed an overall increasing trend with increasing water salinity.The contents of serum glucose and hepatopancreas lactic acid decreased significantly with increasing water salinity,while the levels of serum urea nitrogen,uric acid,and hepatopancreas uric acid showed an increasing trend.The higher contents of triglyceride,total cholesterol and urea nitrogen in the hepatopancreas were detected in 20 and 25 salinity treatments.The activity of total superoxide dismutase in the serum and hepatopancreas of females from 10 salinity treatment was significantly lower than that of other salinity treatments,while the highest levels of total antioxidant capacity,glutathione peroxidase,γ-glutamyl transpeptidase and hemocyanin in the serum,as well as and hepatopancreas glutathione peroxidase and malondialdehyde were detected at 10 salinity treatment.In conclusion,elevating water salinity could promote the growth and ovarian development of adult female P.trituberculatus,and the females had lower levels of metabolism and oxidative stress under the conditions of 20 and25 salinities.