The Ultrastructural Observation on the Secondary Echinococcus Granulosus Cysts in Mice Infected with Protoscoles from Tibetan Sheep and Yak Origins in Qinghai Plateau
Abstract：The ultrastructural observation on the secondary echinococcus granulosus cysts in mice infected with protoscoleces from Tibetan sheep and yak origins in Qinghai plateau were carried out by transmission electron mocroscopy during 1991～1992. The structure of cysts wall of secondary echinococcus granulosus cysts in mice was similar between Tibetan sheep and yak origins ,and was comprised of the laminar layer and the germinal membrane.The laminar layer was layer-shape structure and was comprised of reticulae fibre and irregular electron-dense granular,but the structure was dense in Tibetan sheep original sample and was scatter in yak origin-al sample near germinal membrane. The germinal membrane were divided into tegument and cyton.The microtriches located in outer edge of tegument was short and thin in Tibetan sheep origin sample and was long and fine in yak origin sample,and similar to that of primary echinococcus granulosus cysts,It suggested that the structure and morphology of microtriches be stable,and glycogen mass could be seen in the basal part of tegument of yak origin sample,it suggested that the tegument have active physiological and biochemical functions.The tegumental cells had a great deal of organella,the morphology and structure of mitochondria were similar between primary and secondary echinococcus granulosus cysts in sheep origin sample,but those were different in yak(rigin sample.It suggested that the morphology and structure of mitochondria be not stable and were multi-change in different hosts.The massive vacuoles in which most of walls was single layer,and mitochondria attached to inner edge were observed,these were probably relative to form daughter cysts through development.The results of this paper suggested that the different strains of echinococcus granulosus should probably exist in Qinghai Plateau.
