猪隐孢子虫内生发育虫体超微结构观察

用扫描电镜和透射电镜技术观察了猪隐孢子虫(Cryptosporidium suis)sucp分离株在5日龄仔猪体内内生发育虫体形态结构和寄生特点。结果发现,感染前期和高峰期,在盲肠、结肠和直肠有虫体寄生,而感染后期仅在直肠上发现虫体,并且多集中在肠腺区域。实验观察到滋养体、裂殖体、大配子体、合子和孢子化卵囊等不同阶段的虫体。虫体周围一定区域的微绒毛融合、萎缩或倒伏,肠粘膜上的微绒毛明显脱落。中期滋养体营养器和致密带之间有一层较宽的特殊结构,并且该结构到后期滋养体和裂殖体阶段消失,这层特殊结构尚未见文献报道。在带虫空泡内膜与虫体外膜形成的致密带上方存在典型的呈竖向或斜向排列的纤维塞状结构(microfilament plug)营养器。

THE OBSERVATION ON ULTRASTRUCTURE OF ENDOGENOUS DEVELOPMENT STAGES OF CRPTOSPORIDIUM SUIS

In order to observe the endogenous development characteristics of Cryptosporidium suis sucp strain,five-day-old piglets were inoculated with C.suis sucp strain and samples were observed by transmission electron microscope and scanning electron microscope.The results showed that various stages of C.suis existed in caecum,colon and rectum of the piglets.At the later stages of infection,numerous Cryptosporidia only occurred in rectum.Microvilli of colon and rectum atrophied and desquamated around the Cryptosporidia.One unknown wide band,which probably was filled with nutrition materials,was found between dense band and feeder organelle in metaphase of trophozoites by transmission electron microscope.It,however,disappeared in the other endogenous development stages,including the later stages of trophozoite,various types of merozont and macrogamont.There was a typical feeder organelle,which vertically or sidelongly located above dense band at the bottom of parasitophorous vacuoles.