草鱼呼肠孤病毒Ⅱ型自然发病与人工注射感染草鱼的病理症状和病毒分布研究  

Studies on pathological symptoms and virus distribution in natural and artificial injection infection Ctenopharyngodon idella with grass carp reovirus typeⅡ

作　　者：杨玲 苏建国[1,2,3] YANG Ling;SU Jianguo(College of Fisheries,Huazhong Agricultural University,Wuhan 430070,China;Laboratory for Marine Biology and Biotechnology,Pilot National Laboratory for Marine Science and Technology,Qingdao 266237,China;Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt,Ministry of Education,Wuhan 430070,China)

机构地区：[1]华中农业大学水产学院,湖北武汉430070 [2]海洋科学与技术国家实验室,海洋生物与生物技术实验室,山东青岛266237 [3]华中农业大学长江经济带大宗水生生物产业绿色发展教育部工程研究中心,湖北武汉430070

出　　处：《水产学报》2022年第2期250-260,共11页Journal of Fisheries of China

基　　金：国家重点研发计划“蓝色粮仓科技创新”专项(2018YFD0900504)。

摘　　要：为了探究自然发病和人工注射感染草鱼呼肠孤病毒Ⅱ型(GCRV-Ⅱ型)草鱼的临床症状、病理特征和病毒分布的区别,实验采用临床剖检、组织病理学观察、分子生物学检测、实时荧光定量PCR(qRT-PCR)和蛋白质印迹法(Western blot)等检测方法开展实验,通过对自然发病和人工注射感染草鱼的临床症状进行比较,结果显示,患病草鱼的眼眶、鳃盖、口腔、腹部、鳍条基部、肠道、肌肉出现明显的点状出血,且后者的出血情况比前者更为严重;比较组织病理切片,发现草鱼感染组织出现不同程度的充血和红细胞充盈现象,其中,人工注射感染草鱼的肠道、肌肉和肝胰脏的病变程度更为严重,呈现出较为严重的组织内出血和病变,而自然发病草鱼的鳃和脾脏的病变程度更为严重,鳃呈现出较为严重的充血和炎症增生物,脾脏出现大面积含铁血黄素沉积块病灶。qRT-PCR和Western blot检测结果显示,GCRV在不同的组织中均有分布,头肾在两种感染方式的患病草鱼中的病毒量都比较高,人工注射感染草鱼的肝胰脏、肠道和肌肉的病毒量较高,自然发病草鱼的中肾、鳃和脾脏的病毒量较高。因此,在人工注射感染时,肝胰脏、肠道和肌肉可能是GCRV入侵的主要靶器官,而在自然发病时,鳃可能是GCRV入侵的主要靶器官,病毒聚集靶器官都是头肾,头肾是GCRV的"病毒库"。本研究有助于深入解析GCRV的发病机制和草鱼的免疫响应,同时为草鱼出血病的防治和疫苗的研发提供参考。Grass carp reovirus(GCRV)is one of the main pathogens harmful to the health of Ctenopharyngodon idella,causing severe grass carp hemorrhagic disease.To explore the difference between naturally and artificially injection infected C.idella with GCRV-II virus in clinical symptoms,pathological features,and virus distribution,we used clinical necropsy,histopathological observation,molecular biology detection,real-time fluorescent quantitative(qRT-PCR),and Western blot detection methods for experiments.We compared the clinical symptoms of naturally diseased and artificially injected C.idella,and found that the eye socket,operculum,mouth cavity,abdomen,fin base,intestine and muscle of the diseased C.idella showed obvious punctate hemorrhage.The bleeding of the latter was more serious than that of the former.Compared with histopathological sections,it was found that the infected tissues had different degrees of congestion and erythrocytes accumulation.Among them,the intestines,muscles and hepatopancreas of the artificial injection of C.idella were more severely affected,showing more serious intra-tissue bleeding and lesions.The gills and spleen of naturally diseased C.idella were more severely affected,the gills showed more serious hyperaemia and inflammatory hyperplasia,and large areas of hemosiderin agglutination lesions appeared in the spleen.The results of qRT-PCR and Western blot tests showed that GCRV was distributed in different tissues.The head kidney had a relatively high viral load in diseased fish by the two infection methods.The viral load of the hepatopancreas,intestine,and muscle was higher in artificially injection infected fish.The amount of virus is higher in the trunk kidney,gill,and spleen in naturally diseased fish.Therefore,the hepatopancreas,intestine,and muscle may be the main target organs of GCRV invasion in artificial injection infection,while the gill may be the main target organ of GCRV invasion in the case of natural disease,and the target organ for virus accumulation is the head kidney.The h

关 键 词：草鱼 草鱼呼肠孤病毒 临床症状 组织病理学 病毒分布 

分 类 号：S941.411[农业科学—水产养殖]