【目的】发现异育银鲫Carassius auratus gibelio新病原，为其病害防控提供理论基础。【方法】从吉林省某养殖场采集异育银鲫出血病疑似病样，对其进行细菌分离及寄生虫观察、鲤疱疹病毒Ⅱ型的PCR检测和人工感染试验，然后用感染滤液接种鲤上皮瘤细胞（ EPC ），并对其进行电镜观察。对病毒基因组进行 SDS-PAGE 电泳分析、RT-PCR鉴定及序列测定。【结果】发病异育银鲫无细菌及寄生虫感染，鲤疱疹病毒Ⅱ型的PCR检测无特异性条带，将过滤后的患病鱼组织滤液感染健康异育银鲫，7 d内死亡率高达86.7％。盲传4代后出现明显的细胞病变。负染后电镜下可观察到病毒粒子，直径约70 nm，病毒颗粒近球形，无囊膜结构，初步判断为呼肠孤病毒（暂命名JL-4）。 SDS-PAGE结果揭示，JL-4基因组由11条dsRNA组成，呈现水生呼肠孤病毒基因组典型特征。将RT-PCR扩增产物的序列进行聚类分析，结果显示，JL-4与呼肠孤病毒HZ08株S6序列相似性高达99％，证明该分离株为呼肠孤病毒。【结论】从患病异育银鲫中分离到1株呼肠孤病毒。%Objective] To discover a new pathogen of Gibel carp ( Carassius auratus gibelio) , and to pro-vide a theoretical basis for the disease prevention and control .[Method] Gibel carps suspected having hemorrhagic disease were collected from a farm in Jilin Province .Tissues were observed for bacterial infection and parasite contamination .PCR was used to detect Cyprinid herpes virus-2.Artificial infection was conducted , the infection filtrate was vaccinated to the carp epithelial tumor cells ( EPC ) , and the EPC were observed by an electron microscope .The virus genome was analyzed by SDS-PAGE and identi-fied by RT-PCR and sequencing .[Result] Neither bacterial nor parasitic infection was detected . Cyprinid herpes virus-2 specific bands were not detected by PCR .After healthy Gibel carps were infected with tissue filtrate of sick fish , the mortality rate reached 86.7%within seven days .Clear cytopathy was detected after four generations via blind passage .The virus particles were observed by an electron micro-scope after negative staining , the particle was spherical with around 70 nm in diameter and with no enve-lope.The virus was initially determined as a reovirus strain ( temporarily named JL-4) .The SDS-PAGE results showed that JL-4 possessed 11 segments of dsRNA , which was the typical characteristic of Aquare-ovirus genome.Cluster analysis for the sequences of the RT-PCR amplification product showed that S 6 sequences from JL-4 and reovirus HZ08 had 99% similarity, confirming that JL-4 was reovirus.
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