水体中5-HT对仔蟹生长以及内源5-HT水平的影响

Effects of 5-HT in Water on Growth and the Level of Endogenous 5-HT of Juvenile Crabs,Eriocheir sinensis

已有研究表明外源给予一定量的5-羟色胺(5-HT)可以调控甲壳动物的发育.本实验将同期变态的Ⅰ期仔蟹(仔Ⅰ)单只浸泡于浓度分别为1,3和5μg/mL的5-HT中,浸泡时间分别为1,2和4d,每组20个平行,每个平行1只,待变态成Ⅱ期仔蟹(仔Ⅱ)后观察各组的存活率、变态时间、规格(壳长、壳宽和湿重),并测体内5-HT含量.结果显示:不同浓度的5-HT组间,仔Ⅱ的存活率,规格及体内5-HT含量,各个实验组与对照组间并没有显著差异,且和浸泡时间没有依赖性关系.但是与对照组相比,同一浸泡天数,不同浸泡浓度间,其变态时间有显著差异(P<0.05),且变态时间有随剂量升高而缩短的趋势,如:5μg/mL(浸泡4d)实验组的变态时间(5.41±1.00)d比对照组的(6.74±1.82)d明显缩短约2d.而同一浸泡浓度,不同浸泡天数间并没有显著差异.结果表明:水体中适量的5-HT可能会促进河蟹仔蟹的生长,但最佳作用浓度的选择以及对河蟹的影响是否有阶段性,还需要进一步的深入研究.

Studies have proved that exogenous serotonin（5-HT） can control crustaceans development,so the effect of 5-HT on juvenile crab,Eriocheir sinensis,was investigated in the paper.Juvenile crabsⅠ（single）,which the newly synchronously metamorphosis from Megalopa,were exposed to fresh water including 1,3 or 5μg/mL 5-HT,for a period of 1,2,4 d,20 parallels of each,and only one in each parallel.After metamorphosis into Juvenile crabsⅡ,the survival rate,metamorphosis time,shell length,shell width and wet weight were observed and 5-HT levels of Juvenile crabsⅡ were measured.The results showed that： different concentrations of 5-HT experimental groups,in the stage of Juvenile crabsⅡ,there was no significant difference in the survival rate,the size,and 5-HT levels in vivo,meanwhile,no dependence relationship with soaking time.However,compared with the control,soaking in 5-HT of different concentrations for the same days,there was a significant difference in the metamorphosis time（P0.05）,and abnormal time shortened with the increase of soaking doses,for instance,5μg/mL（immersion for 4d） experimental group,its metamorphosis time（5.41±1.00d） shortened about 2d,compared with the control（6.74±1.82d）.In brief,our results showed that 5-HT in water may promote the growth of juvenile crabs,but the selection of optimal concentration,and at which stage in the role of crab largely,which needs further study.