摘要
采用光学显微镜和电子显微镜技术分别对患迟钝爱德华氏菌(Edwardsiella tarda)病的大菱鲆(Scophthalmus maximus)的病理学变化进行了研究。结果发现,迟钝爱德华氏菌可引起大菱鲆肾脏、脾脏、肝脏、心脏、肠和鳃等多个器官组织发生不同程度的病变,其中以肾脏病理变化最为显著,主要表现为造血组织局部坏死、单核巨噬细胞显著增生和肉芽肿形成。肝脏发生脂肪变性,血窦扩张充满单核巨噬细胞,严重者发生局部坏死;脾脏单核巨噬细胞增生显著,脾实质出现多处局部坏死;心肌纤维变性,肌纤维间有单核巨噬细胞浸润,病变严重者形成局部坏死灶。此外,在病鱼的肠和鳃内也发现大量单核巨噬细胞浸润的现象。研究表明,迟钝爱德华氏菌感染的大菱鲆主要是以单核巨噬细胞来参与炎症反应。爱德华氏菌病的病理分型应属肾脏型或肝肾混合型。
Since 2002,a novel edwardsiellosis in turbot,associated with Edwardsiella tarda was identified in China. Pathological studies were carried out in turbot affected by E. tarda under optical and transmission electron microscope. The aim of the study was to describe the pathological findings observed and to provide scientific basis for the diagnosis and treatment of edwardsiellosis. Eighteen diseased fish ranging from 6-23 cm in body length were collected for pathological observation from six farms. The results showed that there were various degrees of pathological changes in the kidney, spleen,liver,heart,intestine and gills of diseased fish. While several organs seemed to have been affected,the kidney was extremely vulnerable to the infection showing the most prominent and consistent pathological characteristics of this disease such as focal necrosis of hematopoietic tissues,proliferation of mono-macrophages and formation of granulomas. In the kidney of some fish,large numbers of E. tarda were often present with infiltration of microphages. There was fatty degeneration of liver with dilated hepatic sinusoids full of mono-macrophages in most affected fish. For the fish with severe infection,focal necrosis was also often observed in the liver. Large numbers of mono-macrophages were observed in the spleen accompanied by focal necrosis. For the heart,cardiac muscle fibers were degenerative. And large numbers of mono- macrophages were infiltrated between muscle fibers. Focal necrosis composed of necrotic cardiac muscle fibers, macrophages and lymphocytes were observed in the severe heart infection. In addition,obvious infiltration of monomacrophages was also found in the intestine and gills. Granulomas were also occasionally observed in the submucosa of intestines and the primary lamella of gills from some affected turbot. Pathological changes revealed that when the disease was in early stage,the multiple necrotic foci in the tissue were often observed with exudative fibrin. With the disease developed,numerous proliferative mono-macrophages began to appear and phagocyted E. tarda. Then macrophages with bacteria transformed into epithelioid cells which formed into multiple granulomas at last. Mono-macrophages were the main cell type implicated in the inflammatory response of diseased turbot affected by E. tarda. In present study,edwardsiellosis in cultured turbot in China belonged to nephric form or nephric-hepatic form. Further studies are needed to confirm whether there is hepatic form of edwardsiellosis for cultured turbot in China.
出处
《中国水产科学》
CAS
CSCD
北大核心
2009年第3期411-419,共9页
Journal of Fishery Sciences of China
基金
国家‘863’高技术发展项目(2003AA622070).
