Screen Out Environmental Hormone In Vivi Using Marine Nematode Chromadorina Sp.as A Model Organism

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...