【作者】 王摆；

【导师】 汝少国； 姜明；

【作者基本信息】 中国海洋大学 ， 生态学， 2006， 硕士

【摘要】 随着化学物质特别是持久性有机污染物大量排放到环境中,这些化学物质对生物乃至生态系统的内分泌扰乱作用,越来越受到生态毒理学家的关注。目前,各国学者正积极开展环境激素的生物筛选方法研究,而生物筛选方法建立的基础是模型动物的选择。本文以玉米琼脂培养基为载体,在实验室成功地分离并单种传代培养了自由生活海洋线虫Chromadorina sp.,以Chromadorina sp.为模型动物,选择急性致死率、胚胎发育和繁殖为指标,并辅以对消化管、性腺、肌肉和体壁超微结构的观察,研究了久效磷对海洋线虫Chromadorina sp.的毒性和环境激素效应。作为模型动物的Chromadorina sp.,是从青岛栈桥附近潮间带分选出的,经实验室内人工培养,Chromadorina sp.的胚胎、胚后发育特征和生殖行为的形态学、生态学研究结果表明,在23±0.5℃,盐度为26.7条件下,Chromadorina sp.的胚胎发育时间为49.69±2.90 hr,最短世代时间为14 d,四次蜕皮依次发生在第三天、第五天、第七天和第九天,并在第十四天开始产卵。刚孵化的幼虫长约165μm,通体透明,开始摄食后,可以区分透明的咽和不透明的消化管。L1、L2、L3、L4幼虫平均体长分别为227μm、335μm、437μm和528μm。第四次蜕皮后,出现性别分化,性成熟后,体长为638.9±64.8μm,雌雄个体开始交配、产卵。种群的性比为1:1,行两性繁殖,內禀增长率为0.076 d-1。由于Chromadorina sp.世代周期短、发育特征明显、雌雄异体、繁殖快等特点,是研究化学污染物繁殖毒性的理想模型动物。将上述分选出的Chromadorina sp.经过数月传代培养后,暴露在含有久效磷的玉米琼脂平板上。结果表明,久效磷对Chromadorina sp. 24,48,96 hr-LC50分别为66.42、36.94、16.03μM;在0.1-10.0μM范围内的久效磷使Chromadorina sp.胚胎发育延迟,10μM的久效磷影响卵的孵化,1μM久效磷使线虫子一代的数量减少,仅是对照组的52.9%。久效磷抑制了Chromadorina sp.的繁殖,对海洋线虫Chromadorina sp.具有较高毒性和生殖扰乱作用。更多还原

【Abstract】 As large number of chemicals,especially permanent organic pollution are released into the environment, and many of these chemicals are suspected to have endocrine-disrupting activity and thereby affect organisms in many ecosystems. At present, many researchers from different country are endeavoring to develop assay for environmental hormone, and the base to construct the assay is to choose an model organism. In this paper, the local marine nematode Chromadorina sp. were collected and cultivated on cornmeal agar plate, and the toxicity and environment-hormonal activity of monocrotophos are studied using Chromadorina sp. as a model organism, and choosing mortality, embyonic development and reproductive as main endpionts, the changes of intestine, glanod, body muscle and bodywall as assistant indicaters.The model organism marine nematode Chromadorina sp. are collected from intertide nearby Qingdao pier, and cultivated in large numbers in lab. We describe the morphology and ecology of Chromadorina sp.’s embryonic, postembryonic development and reproduction by the means of measuring and recording under a microscope. We find that embryonic development of Chromadorina sp. undergoes 49.69±2.90 hours at 23±0.5℃, 26.7S, and the minimum generation time is 14 days. The four molt time is determined by drawing the postembryonic growth curve, are found to occur at the third, fourth, seventh and ninth day after hatching. Chromadorina sp. lay eggs at the fourteenth day. The hatched larvae is exceeding translucent, after taking food the intestine become opaque and the body length is 165μm. The body length of L1, L2, L3, L4 larvae are 227μm, 335μm, 437μm and 528μm. After the fourth molting, the Chromadorina sp. begin to sexual differentiation. The body length of adult is 638.9±64.8μm. Male and female adults begin to copulate and lay eggs. As Chromadorina sp. having short lifecycle, obvious developmental characters, dioecism, fast reproduction, has been shown to be suitable test organism for assessing the reproductive toxicity of chemicals.After cultivated for several months, the marine nematode Chromadorina sp. are exposured to monocrotophos. The 24, 48, 96hr-LC50 of monocrotophos to更多还原