在巴西,曼氏血吸虫的中间宿主有B.tenagophila、藁杆双脐螺、光滑双脐螺三种双脐螺。本文比较研究了这三种螺的毛蚴感染水平及每天的尾蚴逸出数。 用实验室饲养的长度分别为8—10mm、8—10mm、4—7mm的上述三种双脐螺,进行曼氏血吸虫发育的比较研究。每种螺200只, In Brazil, the intermediate host of Schistosoma mansoni B.tenagophila, double pole snail double smooth, smooth double umbilical snail three snails. This paper comparatively studied the infection levels of these three species of spirochetes and the number of cercariae released per day. Comparative studies on the development of Schistosoma mansoni using the above three species of Umbilical snails, 8-10 mm in length, 8-10 mm in diameter and 4-7 mm in length, were carried out in laboratory. 200 snails each