青海湖裸鲤体腔寄生蠕虫种群动态与宿主食性的关系

STUDIES ON THE DYNAMIC MECHANISM OF CAVITY HELMINTHS IN GYMNOCYPRIS PRZEWALSKII PRZEWALSKII IN THE QINGHAI LAKE Ⅰ: ECOLOGICAL APPROACH AND THEIR RELATIONSHOP TO FEEDING OF HOST

对盲囊线虫在青海湖中以锯缘真剑水蚤作为第一中间宿主 ,舌状绦虫和裂头绦虫都以咸水北镖水蚤和锯缘真剑水蚤作为第一中间宿主 ,青海湖裸鲤对咸水北镖水蚤的摄食量随体长增加而增加 ,对锯缘真剑水蚤摄食量随体长增加的变化则不明显。因而提出 :舌状绦虫在不同大小的青海湖裸鲤中的种群数量变化不是由于宿主的摄食习性改变引起的。

The present paper dealed with the first intermediate hosts of three species of helminths, Ligula intestinalis, Diphyllobothrium sp. and Contracaecum rudolphii , from the cavity of fish Gymnocypris przewalskii przewalskii (in the Qinghai Lake) which were being fed by the fish host of different size. The results showed that both Ligula intestinalis and Diphyllobothrium sp used Arctodiaptomus salinus and Eucyclops serrulatus as intermediate hosts, but Contracaecum rudolphii only infected E. Serrulatus. Larger fish significantly consumed more A. salinus, but not significantly more E. serrulatus. The population’s extinction of L. intestinalis in fish larger than 200 mm was not due to fish’s feeding change to the intermediate hosts. The population increases of Diphyllobothrium sp. and C. rudolphii with the growth of fish was related to the increasing composition of larger fish to the intermediate host and the accumulation of worms in the cavity of host.