title: Cyprinid herpesvirus 2 infection emerged in cultured gibel carp, Carassius auratus gibelio in China.
abstract: An epizootic with severe mortality has emerged in cultured gibel carp, Carassius auratus gibelio, in China since 2009, and caused huge economic loss. The signs and epidemiology background of the disease were investigated. Parasite examination, bacteria and virus isolation were carried out for pathogen isolation. The causative pathogen was obtained and identified as Cyprinid herpesvirus 2 (CyHV-2) by experimental infection, electron microscopy, cell culture, PCR assay and sequence alignment, designated as CyHV-2-JSSY. Experimental infection proved the high virulence of CyHV-2-JSSY to healthy gibel carp. Electron microscopy revealed that the viral nucleocapsid was hexagonal in shape measuring 110-120 nm in diameter with a 170-200 nm envelope. The virus caused significant CPE in Koi-Fin cells at the early passages, but not beyond the fifth passages. Sequence alignment of the partial viral helicase gene (JX566884) showed that it shared 99-100% identity to the published sequences of other CyHV-2 isolates. This study represented the first isolation and identification of CyHV-2 in cultured gibel carp in China and laid a foundation for the further studies of the disease.
authors.affiliation: Division of Fish Disease, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences; The Key Laboratory of Yangtze River Basin's Aquatic Animal Diseases, the Ministry of Agriculture of China, Wuhan 430223, PR China.
authors.forename: Jin
authors.initials: J
authors.lastname: Xu
authors.forename: Lingbing
authors.initials: L
authors.lastname: Zeng
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhou
authors.forename: Jie
authors.initials: J
authors.lastname: Ma
authors.forename: Yuding
authors.initials: Y
authors.lastname: Fan
mesh_terms: D000818:Animals; D017756:Aquaculture; D002681:China / Q000453:epidemiology; D003530:Cyprinidae / Q000254:growth & development / Q000821:virology*; D005393:Fish Diseases / Q000453:epidemiology / Q000503:physiopathology / Q000821:virology*; D006564:Herpesviridae / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D006566:Herpesviridae Infections / Q000453:epidemiology / Q000503:physiopathology / Q000662:veterinary* / Q000821:virology; D010802:Phylogeny
keywords: Cyprinid herpesvirus 2; Epizootic; Gibel carp (Carassius auratus gibelio); Identification; Isolation; Pathogenicity