一种虹彩病毒感染大菱鲆的病理学研究

Pathological study on the infection of Scophthalmus maximus by an iridovirus

中文关键词: 大菱鲆  虹彩病毒  病理学  肿大细胞

英文关键词: Scophthalmus maximus  Iridovirus  Pathology  Enlarged cells

中文摘要:

      对我国虹彩病毒感染的大菱鲆Scophthalmus maximus进行的组织病理和超微病理学研究发现，该病典型的病理学特点是在病鱼的脾脏、肾脏、肠、肝脏、鳃、心脏和皮肤等器官组织内出现嗜碱性的肿大细胞。病毒感染导致患病大菱鲆多个器官组织发生了不同程度的病理变化，其中以脾脏组织的病理变化最为显著，表现为造血组织的严重坏死。此外，肾脏造血组织发生坏死、肠固有膜和黏膜下层出血和水肿、肝细胞水样变性、心肌局灶性坏死以及皮肤真皮层出血并伴有水肿和炎性渗出也是该病常见的组织病理学变化。超微病理研究表明，肿大细胞内有虹彩病毒粒子存在。病毒分布于受感染细胞的胞质、组织间隙以及血管腔内。受感染细胞出现线粒体和内质网等细胞器肿胀、崩解等细胞病理变化。研究认为，病毒感染造成皮下组织血管损伤出血，是虹彩病毒感染的大菱鲆发生“红体病”的原因所在。虹彩病毒感染所致的机体严重贫血是患病大菱鲆死亡的主要原因，而主要器官组织的病变使得病鱼器官功能衰竭则可加速鱼的死亡。

英文摘要:

      Pathological study on Scophthalmus maximus affected by an iridovirus in China revealed that the most prominent and consistent characteristics of this disease were the basophil enlargement of cells, mainly in the spleen, and also in the kidney, intestine, liver, gill, heart and skin. There were various pathological changes to the tissues associated with iridovirus. The spleen suffered the marked pathological changes with the heavy necrosis of hematopoietic tissue. In addition, necrosis of hematopoietic tissue in kidney, haemorrhage and oedema in submucosa of intestine, hydropic degeneration of hepatic cells, local necrosis of cardiac muscle and hemorrhage with inflammatory exudation in dermis were also observed. Electron microscopy showed that numerous viral particles were present in the enlarged cells. The viral particles were distributed in the cytoplasm, tissue interstice and lument of blood vessel. Cells infected by the virus presented obvious cytopathological changes. The mitochondria and endoplasmic reticulum fragmented and dissolved in the swollen cytoplasm. The haemorrhage in subcutaneous tissue with virus infection was responsible for the reddish appearance of diseased turbot. Anaemia caused by the virus infection was the main cause of death in affected fish and organ failure as a result of tissue necrosis also accelerated the death of diseased fish.