【摘要】 采用扫描电镜观察了贝氏隐孢子虫在珍珠鸡体内的发育。大量球形虫体镶嵌于气管和法氏囊微绒毛丛中。气管纤毛消失，微绒毛生发生融合。法氏囊粘膜表面可观察到宿主细胞突起，在突起的表面有数个虫体寄生。滋养体呈球状，平均大小为１．７μｍ。裂殖体拥有４个或８个香蕉状裂殖子。成熟大配子体大小为 ４.２ × ３．３μｍ，在其侧面可观察到锯齿状突起。偶尔能观察到卵囊，其表 面有一明显裂缝。虫体逸出后所留下的带虫空泡似弹坑状，根据其结构可将其分为两类，其中一类为裂殖子或小配子的形成场所，另一类为卵囊的形成场所。更多还原

【Abstract】 Oocysts of Cryptospor: dium baileyi isolated from ducks were orally inoculated into thirty guinea fowls to observe the development of this organism by scanning electron microscope. A large number of spherical organisms with different sizes were embeded in the mi crovilli of the tracheas and bursas of Fabricius (BF). The cilia of tracheas were lost, and the microvilli became fused. Detached epithelial cells were sometimes observed on the mucosal surface of tracheas. There was host cell protruding on BF, with several organisms on.its surface. The trophozoite was spherical, averaged 1. 7um in size. The trophozite developed into the schizont, in which four or eight merozoites were formed. The mature merozoites were banana-shaped, and located within the parasitophorous vacuole. After removing from the parasitophorous vacuole, the merozoites dispersed to look for suitable sites of invasion. in the early stage of invasion, the meroxoite attached its anterior end to the epithelial cells followed by swelling of the anterior end. Finally, the merozoite developed into trophozoite. The trophozoite underwent subsequently schizogony or gametegony. The well-developed macrogametocyte was 4. 2× 3. 3μm in size, and the serrated prominences could be seen on the lateral aspect of the macrogametocyte. Oocysts having the characteristic cleft were found only occassionly. Two forms of crater-like structures were observed. One of them, possessing a residual body at its base, was .formed after the merozoites or microgametes escaped. The other, characterized by a feeder organelle at its base, was formed after the oocyst left.更多还原