Fried B, Stableford L T
Department of Biology, Lafayette College, Easton, Pennsylvania 18042.
Adv Parasitol. 1991;30:108-65.
A total of 23 species from 14 families of the Digenea have been studied in chick embryos, mainly on the chick chorioallantoic membrane (CAM). Most species for which cultivation has produced ovigerous adults in chick embryos have been avian digeneans with progenetic metacercariae. Less success has been obtained with the hermaphroditic, non-progenetic, economically important trematodes such as fasciolids and echinostomatids, although post-metacercarial development has been achieved for Fasciola hepatica and Echinostoma trivolvis (synonym of E. revolutum) (see Fried and Butler, 1979; Fried and Pentz, 1983). Success with human or animal blood flukes has been minimal, although adults of Schistosoma mansoni and Spirorchis spp. (turtle blood flukes) have at least been maintained on the CAM (see Fried et al., 1982; Fried and Tornwall, 1969). Schistosome cercariae and in vitro transformed cercariae (schistosomules) should be tested in chick embryos. Marine avian schistosomes in the genera Austrobilharzia and Ornithobilharzia, along with the freshwater avian schistosome Trichobilharzia, would provide useful material for avian embryo studies on non-human schistosomes. Studies on trematodes in chick embryos have been done mainly to gain basic biological information on these parasites. That is, to identify species for which definitive hosts are not available; for studies on worm-intraspecific variation, growth and development; for studies on worm feeding and digestion; and for studies on worm-mediated chemoattraction and worm site location on the CAM (Fried, 1989). Sites other than the upper surface of the CAM have not been well-explored for digeneans, although Irwin and Saville (1988a,b) have examined the subchorioallantois and allantois as habitats for stigeids and microphallids. They have also studied the effects of serum supplements to the embryo on the enhancement of worm growth and development. Irwin and Saville's work should be extended to other helminths. The albumen in the hen's egg is a good site for the development of Clinostomum marginatum and Amblosoma sawaense (see Larson and Uglem, 1990; Fried et al., 1981), but the reasons for the better growth of these parasites in the albumen than on the CAM are not known. The inoculation of trematode larvae into CAM blood vessels, the yolk sac, the amnion and the embryo proper have not been explored and may provide useful avenues of research. Only a single study has been done with a monogenean trematode, Polystomoides sp. (see Fried, 1965), in which worms were grown on the CAM at 30 degrees C.(ABSTRACT TRUNCATED AT 400 WORDS)
在鸡胚中已对复殖目14个科的共23个物种进行了研究，主要是在鸡胚绒毛尿囊膜（CAM）上进行的。在鸡胚中培养出带卵成虫的大多数物种都是具有幼体性后尾蚴的禽类复殖吸虫。对于雌雄同体、非幼体性、具有经济重要性的吸虫，如片形吸虫和棘口吸虫，培养成功率较低，尽管肝片吸虫和三歧棘口吸虫（卷棘口吸虫的同义词）已实现了后尾蚴后的发育（见弗里德和巴特勒，1979年；弗里德和彭茨，1983年）。对人体或动物血吸虫的培养成功案例极少，尽管曼氏血吸虫和旋睾属吸虫（龟类血吸虫）的成虫至少已在CAM上维持存活（见弗里德等人，1982年；弗里德和托恩瓦尔，1969年）。血吸虫尾蚴和体外转化的尾蚴（童虫）应在鸡胚中进行测试。澳大利亚血吸虫属和鸟血吸虫属的海洋禽类血吸虫，以及淡水禽类血吸虫毛毕吸虫，将为禽类胚胎中关于非人血吸虫的研究提供有用材料。对鸡胚中吸虫的研究主要是为了获取这些寄生虫的基础生物学信息。也就是说，用于鉴定没有终末宿主的物种；用于研究虫体种内变异、生长和发育；用于研究虫体摄食和消化；以及用于研究虫体介导的化学吸引和虫体在CAM上的定位（弗里德，1989年）。对于复殖吸虫，除了CAM上表面之外的其他部位尚未得到充分探索，尽管欧文和萨维尔（1988a、b）已将绒毛尿囊膜下层和尿囊作为茎双腔吸虫和微茎科吸虫的栖息地进行了研究。他们还研究了向胚胎添加血清对虫体生长和发育的促进作用。欧文和萨维尔的工作应扩展到其他蠕虫。鸡蛋中的蛋白是缘口吸虫和泽氏并殖吸虫发育的良好场所（见拉森和乌格勒姆，1990年；弗里德等人，1981年），但这些寄生虫在蛋白中比在CAM上生长得更好的原因尚不清楚。将吸虫幼虫接种到CAM血管、卵黄囊、羊膜和胚胎本身尚未进行探索，可能会提供有用的研究途径。仅对一种单殖吸虫多盘虫属物种进行过一项研究（见弗里德，1965年），其中虫体在30摄氏度的CAM上生长。（摘要截取自400字）
