斑点叉尾(鱼回)疑似疱疹病毒感染的病理形态学观察

对四川省一些养殖场斑点又尾鮰大规模死亡的病鱼组织进行了光镜和电镜观察．在其肾和肝组织的细胞中发现一种圆形或椭圆形病毒颗粒，有囊膜的病毒颗粒存在于胞浆中，直径150～200nm．无囊膜的病毒颗粒既存在于胞浆中，也存在于胞棱中，直径为80～110nm，同时在细胞核内可见无病毒核心的空衣壳，根据其形态特征初步确定为一种疱疹病毒。病鱼主要表现为鳍条基部和皮肤（特别是腹部和尾柄）充血、出血，腹部膨大，眼球突出．鳃发白．腹腔内充有淡黄色或淡红色的腹水，胃肠道扩张，其内充满大量淡黄色的粘液，肝、脾和肾肿大。病理组织学变化主要为全身组织器官广泛性水肿、出血、变性、坏死和炎症细胞浸润，特别是肾、肝、胃肠道、脾和脑的损伤较为严重。肾间质水肿，造血组织坏死，巨噬细胞和中性拉细胞浸润．肾小管上皮细胞空泡变性和坏死；肝水肿，狄氏间隙增宽．肝细胞空泡变性及坏死；胃肠道粘膜上皮变性，坏死．脱落，固有膜，粘膜下层水肿，淋巴细胞、巨噬细胞和中性枉细胞浸润；脾淤血．出血．淋巴细胞减少，大量巨噬细胞和中性粒细胞浸润；脑水肿，神经细胞肿胀．甚至坏死固缩。超微结构上．被病毒感染的细胞发生明显的痛变，线粒体肿胀，嵴断裂．溶解，粗面内质网扩张，核糖体颗粒脱落．细胞核体积增大，染色质浓缩．边集。

Pathomorphologic Observation of Channel Catfish Ictalunes punctatus Infected with Herpesvirus

Since 1999,there has been the outbreak of an acute lethal disease of channel catfish(Ictalunes punctatus) in many farms of Sichuan province.The pathology of diseased channel catfish have been studied by light and election microscope examination.There are many round or oval viruses in liver and kidney.The virus with envelope in the cytoplasm has a diameter of 150-200 nm;but the diameter of non-envelope virus in the cell nucleus and cytoplasm is around 80-110 nm,and the empty capsomeres without nucleal core were found in many cell nuclei.According to the morphology,the virus is classified tentatively as a herpesvirus.Gross changes examination revealed congestion and hemorrhage at the base of fins and in skin(especially abdomen and peduncle),distension of abdomen,exophthalmia,pale gills;yellowish or slightly reddish fluid in the peritoneal cavity,distension of gastrointestinal tract with yellowish mucus,swelling in the liver,spleen and kidney.Histopathological examination showed a severe hemorrhage,edema and necrotic changes in many organs including inflammatory cell infiltration;especially,serious lesions occurred in the kidney,liver,gastrointestinal tract,spleen and brain.The kidney showed edema,degeneration and necrosis in renal tubular epithelia,and necrosis with macrophages and neutrophi infiltration in the hematopoietic tissue.The liver showed edema,vacuolar degeneration and foci necrosis.Epithelia mucosa of the gastrointestinal tract underwent degeneration and necrosis;the lamina propria and tunica submucosa showed edema and infiltration with lymphocytes,macrophages and neutrophls.The spleen showed congestion,hemorrhage,diminution of lymphoid tissue and infiltration with macrophages and neutrophls.The brain showed edema;degeneration and necrosis in neurons.Ultrastructurally,severe lesions appeared in virus-infected cells,the mitochondria swelled with disintegration and lyses of the cristaes.The rough endoplasmic reticulum dilated and many ribosomes were detached from it.The cell nuclei enlarged and the chromatin occured condensation and margination.