桶形芋螺和菖蒲芋螺的性畸变  

Imposex of Conus betulinus and Conus vexillum

作　　者：朱四喜[1] 董巧香[1,2] 沈金辉[3] 于秀娟[1] 杜虹[1] 黄长江[1] 

机构地区：[1]汕头大学科技中心水生生物技术与环境资源保护研究所 [2]AquacultureResearchStation,LouisianaStateUniversityAgriculturalCenter,LouisianaAgriculturalExperimentStation,BatonRouge,Louisiana70803,USA [3]汕头市中心医院病理科

出　　处：《生态学报》2005年第2期289-297,共9页Acta Ecologica Sinica

基　　金：国家自然科学基金资助项目 (4 0 1760 2 9) ;广东省重大科技兴海资助项目 (A2 0 0 0 0 5 F0 2 ) ;广东省自然科学基金资助项目 (0 0 0 792 )~~

摘　　要：2 0 0 1年 9月和 2 0 0 3年 8月在广东湛江的硇洲岛和 2 0 0 3年 6月在广东阳江的闸坡渔港采集桶形芋螺 (Conus betulinus)和菖蒲芋螺 (Conus vexillum) ,发现两个海区的芋螺雌性个体均发生性畸变 ,性畸变率均为 10 0 % ,但雌 /雄性比仍大于 1.0。两种芋螺的畸变阶段和类型多 ,桶形芋螺有 S3b、S3c、 S4 、S*4 、S5b、S5c,而菖蒲芋螺有 S1 c、S3b、S4 、S*4 、S6 b。 2 0 0 3年 6月在阳江采集的桶形芋螺畸变程度最高 ,种群 RPSI为 5 3.8% ,VDSI高达 4 .9,雌性不育率达 4 4 .0 %。 2 0 0 1年 9月在硇洲岛外海深水区采集的菖蒲芋螺的种群 RPSI虽然只有 14 .7% ,但性畸率为 10 0 % ,VDSI也达 4 .1%。由此可见 ,两种芋螺对有机锡污染均比较敏感 ,而且有个体大、易采集、性畸变率高、畸变阶段跨度大、畸变类型多、畸变特征易于鉴别等特点 ,是中国东南沿海低潮线和潮下带有机锡污染生物监测的理想指示种。如与潮间带有机锡污染指示种疣荔枝螺 (Thaisclavigera)结合起来 ,便可相互补充 。Organotin compounds, especially tributyltin (TBT), are widely used as biocidal additives in antifouling paints because of their effectiveness. However, they also cause severe damages to non-target organisms while they kill fouling organisms. For example, TBT has been reported to induce imposex in gonochoristic gastropods, that is, imposition of male sexual organs such as penis and vas deferens on female sexual organs. In the present study, we describe anatomical and histological structures of imposex genital sysytem of Conus betulinus and C. vexillum, and evaluate their imposex and possibility as an ideal biomonitor in organotin contamination along the Southeast China Sea. Conus betulinus and Conus vexillum were collected from Naozhou Island of Zhanjiang and Zhapo Fishery Harbor of Yangjiang in Guangdong in September of 2001 and June and August of 2003. After they were identified to the species, the samples were narcotized using 7% MgCl_2 in distilled water, and the salient features of the reproductive system were examined with a stereomicroscope. The external genital characters (e.g. vas deference and penis) were differentiated with the divisional system established by Fioroni et al in 1991, and vas deference extension and penis length were measured to the nearest 0.1 mm. The genital tracts of males and imposex females were embedded in paraffin, and serial sections were cut and stained with azan. The anatomical and histological photographs were taken with a Zeiss Axicam, and analyzed with the analytic system of Axio Vision. To evaluate the degree of imposex, the imposex indices such as incidence of imposex (IOI), sex ratio index (SRI), relative penis size index (RPSI), vas deference sequences index (VDSI), and the percentage of sterile females per sample (%STER) were calculated by the methods of Gibbs et al in 1987 and Barroso et al in 2002. All female of Conus were found to be imposex, and 93.4% imposex individuals were found having penis and vas deference. The stages of imposex in Conus included S_(1c)

关 键 词：桶形芋螺(Conus betulinus) 菖蒲芋螺(Conus vexillum) 性畸变 有机锡 指示种 

分 类 号：X55[环境科学与工程—环境工程] Q958[生物学—动物学]