三角帆蚌嗜水气单胞菌病的病理研究

Study on Pathology of Hyriopsis cumingii Lea Disease Caused by Aeromonas hydrophila

采用生物显微镜和透射电镜观察了三角帆蚌人工感染嗜水气单胞菌后肝脏、肠道、鳃、斧足、闭壳肌等主要器官的组织和细胞病理变化 .病蚌临床症状与自然染病症状相似 ,病变早期 ,体内有大量粘液排出体外 ,蚌壳后缘出水管喷水无力 ,两壳微开 ;病变后期 ,闭壳肌失去功能 ,两壳张开 ,肠道水肿 ,有腹水 ,肠内无食物 ,肝脏呈糜烂状 ,斧足苍白 ,鳃暗黄 .组织及细胞超微结构观察可见 ,嗜水气单胞菌对肝脏危害最为严重 ,肝小管肿大破裂 ,管腔变小甚至完全堵塞 ;肝细胞肿大变性 ,胞浆内出现空泡 ,细胞核溶解 ,水肿变性直至坏死 ,间质中大量的嗜酸性细胞浸润 .其次是鳃 ,鳃丝细胞排列松散 ,纤毛受到不同程度的破坏 ,甚至脱落 ,隐窝深处细胞坏死 ,水肿 ,细胞内及细胞间出现空泡 ,粗面内质网扩张 .嗜酸性细胞局部聚集 。

The histopathological and cytopathological changes of major organs such as liver,gill,leg,shutting shell muscle from Hyriopsis cumingii Lea diseased by means of artificial infection with Aeromonas hydrophila were observed by using microscope and TEM for discovering pathomorphological changes of Hyriopsis cumingii Lea disease and its mechanism.The clinical symptoms were similar to that occuring in natural cases.At the early stage of the disease,there was much extrudative mucilage in the body of sick Hyriopsis cumingii Lea,and the spraying of water nozzle in its back shell was weak and the two shells opened slightly.With the progress of disease,the shutting shell muscle didn't work,and the shells opened widely.Sick Hyriopsis cumingii Lea had intestinal edema and ascites with no food in intestine,erosion like liver,pale leg and darken yellow gill.The histological and cytological observation showed that the damage to the liver caused by Aeromonas hydrophila was the most serious,which caused intumescentia and break of liver canaliculus,even the canaliculus became small until blocked completely.Liver cell degenerated and swelled,there were vacuoles in plasm.In celledema degeneration,necrosis and karyolysis occurred.Many eosinophilic cells were in interstical tissue.The damage to gill was less serious.The arrangement of gill cell was loose,Gilia was damaged in different degrees,and even shedded.The cell in the deep of crypt occured necrosis,edema,vacuole in cells and between cells,dilation of rough endoplasmic.Eosinophilic cells were focal aggregation,and secretory cells were calcified.