盐度驯化对雌性日本鳗鲡形态特征及性腺发育的影响  

Effects of salinity acclimation on morphological characteristics and gonadal development of female Anguilla japonica

作　　者：夏瑛 黄晓荣[1,2] 刘鉴毅[1,2] 张涛[1,2] 庄平[1,2] 赵峰[1,2] XIA Ying;HUANG Xiaorong;LIU Jianyi;ZHANG Tao;ZHUANG Ping;ZHAO Feng(College of Fisheries and Life Science,Shanghai Ocean University,Shanghai 201306,China;Key Laboratory of East China Sea Fishery Resources Exploitation,Ministry of Agriculture and Rural Affairs,East China Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences,Shanghai 200090,China)

机构地区：[1]上海海洋大学水产与生命学院,上海201306 [2]中国水产科学研究院东海水产研究所,农业农村部东海渔业资源开发利用重点实验室,上海200090

出　　处：《中国水产科学》2024年第1期29-39,共11页Journal of Fishery Sciences of China

基　　金：中央级公益性科研院所基本科研业务费专项资金资助项目(2022XT02,2023TD14)。

摘　　要：为查明盐度驯化对5龄雌性日本鳗鲡(Anguilla japonica)形态特征及性腺发育的影响,通过150 d的模拟盐度驯化实验,分析雌鳗在不同盐度驯化下的形态特征和性腺发育状况。结果显示,从盐度0~35依次驯化至90d(在盐度15、25、35依次分别驯化30d)时,雌鳗的胸围(PC)、胸鳍指数(PI)、性体指数(GSI)和肝脏指数(LI)随盐度的升高均显著增加(P<0.05);而消化道指数(DTI)和眼径指数(EI)随盐度的升高均无明显变化(P>0.05)。通过对卵巢切片观察发现,雌鳗的卵母细胞直径(OD)随盐度的升高显著上升(P<0.05),但卵母细胞始终处于脂肪泡时期。在盐度35中继续驯化,发现雌鳗在第90、120和150天的上述7项指标在各盐度组间均不存在显著性差异(P>0.05)。为了解流水对雌鳗性腺发育的影响,设置了同步盐度驯化的流水组。结果显示,在整个盐度驯化过程中,流水组雌鳗7项指标的变化趋势与静水组一致,除卵母细胞直径(OD)外的其他6项指标与同一驯化盐度下的静水组均无显著性差异(P>0.05)。流水组的卵母细胞直径(OD)均显著高于同一驯化盐度下的静水组(P<0.05),且在盐度35驯化30d后,流水组的卵母细胞进入初级卵黄球时期,卵母细胞直径达到(161.97±7.46)μm,显著高于静水组的(140.46±9.36)μm(P<0.05)。通过对静水组和流水组雌鳗血清中促性腺激素含量的测定发现,整个盐度驯化期间,静水组和流水组雌鳗在各盐度下的黄体生成素(LH)含量均无显著性变化(P>0.05),流水组雌鳗的LH含量与同一盐度下静水组也无显著差异(P>0.05)。盐度驯化对静水组和流水组雌鳗的卵泡刺激素(FSH)均有显著性影响,经盐度35驯化30 d后,流水组FSH含量达(39.66±1.78) U/L,显著高于静水组的(36.97±1.52) U/L (P<0.05)。综上表明,盐度是雌性日本鳗鲡性腺发育的重要启动因子,流水刺激能够加速卵母细胞的早期发育,促进FSH的合成。研究结果可为日本鳗鲡繁殖The effects of salinity acclimation on the morphological characteristics and gonadal development of 5-year-old female Japanese eels(Anguilla japonica)were investigated.A 150-day salinity acclimation experiment was conducted to analyze the morphological features and gonadal development of female eels under different salinity conditions.The results showed that,as salinity increased from 0 to 35 over a period of 90 d(with 30 d of acclimation at salinities 15,25,and 35,respectively),the pectoral circumference(PC),pectoral fin index(PI),gonadosomatic index(GSI),and liver index(LI)of female eels significantly increased(P<0.05),while the digestive tract index(DTI)and eye diameter index(EI)showed no significant changes with increasing salinity(P>0.05).Ovarian histological observations revealed a significant increase in oocyte diameter(OD)with increasing salinity(P<0.05),although the oocytes remained in the oil droplet stage.After continued acclimation to salinity 35,no significant differences were observed in the aforementioned seven indices at 90,120,and 150 d(P>0.05).To investigate the effects of flowing water on female eel gonadal development,a flowing water group was acclimated to varying salinities.The results showed that the trends of changes in the seven indicators in the flowing water group of female Japanese eels during the salinity acclimation process were consistent with those of the still water group.Except for OD,the other six indicators in the flowing water group at the same acclimation salinity level showed no significant differences compared with the still water group(P>0.05).The OD in the flowing water group was significantly larger than that in the still water group at the same salinity(P<0.05).After 30 d of acclimation at salinity 35,oocytes in the flowing water group entered the primary yolk globule stage,with an oocyte diameter of(161.97±7.46)μm,which was significantly larger than that of the still water group at(140.46±9.36)μm.Determination of gonadotropin levels in the serum of female eels in t

关 键 词：日本鳗鲡 盐度驯化 形态特征 性腺发育 促性腺激素 

分 类 号：S917[农业科学—水产科学]