异育银鲫造血器官坏死症病鱼体内鲤疱疹病毒Ⅱ型的电镜观察与超微病理学特征

Ultra-pathological Observation of Cyprinid Herpesvirus 2(CyHV-2)of Allogyogenetics Silver Crucian Carp(Carassius auratus gibelio)with Hematopoietic Necrosis

为分析患鲫造血器官坏死症异育银鲫Carassius auratus gibelio体内不同器官组织中鲤疱疹病毒（CyHV-2）粒子的形态结构、分布和发生过程,采集患病异育银鲫体肾、脾脏、头肾、肝胰脏、肠道、鳃各组织样本,利用透射电镜观察疱疹病毒和组织细胞超微病理学。在所采集器官组织中均观察到鲤疱疹病毒Ⅱ型的DNA内核、空衣壳、实心核衣壳、含包膜成熟病毒共4种不同成熟时期的病毒粒子,不同时期的病毒粒子直径分别为65-90nm、90-180nm、90-180nm、170-220nm;体肾和脾脏中含有大量的Cy HV-2病毒,而头肾、肝胰脏、肠道和鳃中病毒粒子较少;CyHV-2病毒主要感染体肾、头肾、脾脏的吞噬细胞,导致机体免疫机能改变;组织细胞病理学观察发现吞噬细胞核边缘化,核内染色质变性,核膜溶解,线粒体嵴断裂,出现空泡,个别细胞溶解坏死。通过PCR检测和电镜观察病毒粒子结构特征,确诊异育银鲫感染Cy HV-2病毒,主要器官组织细胞中均有CyHV-2病毒,且在细胞核中完成复制和组装,在细胞质中获得外膜。感染Cy HV-2病毒的异育银鲫主要器官组织均受到一定的损伤。

The ultrastructural pathology was observed in mesonephros, spleen, pronephros, hepatopancreas, intestine, and gill of allogyogenetics silver crucian carp（Carassius auratus gibelio） with hematopoietic necrosisby transmission electron microscopy in order to analyze the morphology of cyprinid herpesvirus 2（CyHV-2）distribution and occurrence process in allogyogenetics silver crucian carp with hematopoietic necrosis. CyHV-2 was detected in the all organizations, and had four different maturity periods and diameters, 65-90 nm in DNA core, 90-180 nm in empty capsid, 90-180 nm in solid nuclear capsid, and 170-220 nm in enveloped viral particles. There were a large number of CyHV-2 viruses in mesonephros and spleen, with less CyHV-2 virus in pronephros,hepatopancreas, intestine and gill. Electron microscopy observation revealed that immune cells were infected with CyHV-2, which maylead to immune function change. Ultra-structurally, marginalized nucleus, nuclear chromatin degeneration, disrupted nuclear membranes were observed in the phagocytes in above organs, including the swollen markedly mitochondria and pieces of some dissolved cells. The findings show that CyHV-2 can be diagnosed by characteristics of the virus particles via PCR and electron microscopy. The CyHV-2 is observed in major organs of unhealthy allogyogenetics silver crucian carp, and primarily replicated and assembled in the nucleus, and then obtain the envelope in the cytoplasm.