title: Experimental infections of different carp strains with the carp edema virus (CEV) give insights into the infection biology of the virus and indicate possible solutions to problems caused by koi sleepy disease (KSD) in carp aquaculture.
abstract: Outbreaks of koi sleepy disease (KSD) caused by carp edema virus (CEV) may seriously affect populations of farmed common carp, one of the most important fish species for global food production. The present study shows further evidence for the involvement of CEV in outbreaks of KSD among carp and koi populations: in a series of infection experiments, CEV from two different genogroups could be transmitted to several strains of naïve common carp via cohabitation with fish infected with CEV. In recipient fish, clinical signs of KSD were induced. The virus load and viral gene expression results confirm gills as the target organ for CEV replication. Gill explants also allowed for a limited virus replication in vitro. The in vivo infection experiments revealed differences in the virulence of the two CEV genogroups which were associated with infections in koi or in common carp, with higher virulence towards the same fish variety as the donor fish. When the susceptibility of different carp strains to a CEV infection and the development of KSD were experimentally investigated, Amur wild carp showed to be relatively more resistant to the infection and did not develop clinical signs for KSD. However, the resistance could not be related to a higher magnitude of type I IFN responses of affected tissues. Despite not having a mechanistic explanation for the resistance of Amur wild carp to KSD, we recommend using this carp strain in breeding programs to limit potential losses caused by CEV in aquaculture.
authors.affiliation: Fish Disease Research Unit, Institute for Parasitology, University of Veterinary Medicine, Bünteweg 17, 30559, Hannover, Germany. Mikolaj.Adamek@tiho-hannover.de.
authors.forename: Mikolaj
authors.identifier: 0000-0003-4890-3164
authors.initials: M
authors.lastname: Adamek
authors.affiliation: Fish Disease Research Unit, Institute for Parasitology, University of Veterinary Medicine, Bünteweg 17, 30559, Hannover, Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Oschilewski
authors.affiliation: Department of Pathology, University of Veterinary Medicine, Bünteweg 17, 30559, Hannover, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Wohlsein
authors.affiliation: Fish Disease Research Unit, Institute for Parasitology, University of Veterinary Medicine, Bünteweg 17, 30559, Hannover, Germany.
authors.forename: Verena
authors.initials: V
authors.lastname: Jung-Schroers
authors.affiliation: Fish Disease Research Unit, Institute for Parasitology, University of Veterinary Medicine, Bünteweg 17, 30559, Hannover, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Teitge
authors.affiliation: Fish Disease Research Unit, Institute for Parasitology, University of Veterinary Medicine, Bünteweg 17, 30559, Hannover, Germany.|School of Life Sciences, Keele University, Keele, ST5 5BG, UK.
authors.forename: Andy
authors.initials: A
authors.lastname: Dawson
authors.affiliation: South Bohemian Research Centre of Aquaculture and Biodiversity of Hydrocenoses, Faculty of Fisheries and Protection of Waters, University of South Bohemia in Ceske Budejovice, Zatisi 728/II, 389 25, Vodnany, Czech Republic.
authors.forename: David
authors.initials: D
authors.lastname: Gela
authors.affiliation: South Bohemian Research Centre of Aquaculture and Biodiversity of Hydrocenoses, Faculty of Fisheries and Protection of Waters, University of South Bohemia in Ceske Budejovice, Zatisi 728/II, 389 25, Vodnany, Czech Republic.
authors.forename: Veronika
authors.initials: V
authors.lastname: Piackova
authors.affiliation: South Bohemian Research Centre of Aquaculture and Biodiversity of Hydrocenoses, Faculty of Fisheries and Protection of Waters, University of South Bohemia in Ceske Budejovice, Zatisi 728/II, 389 25, Vodnany, Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Kocour
authors.affiliation: Experimental Fish Farm in Zator, The Stanislaw Sakowicz Inland Fisheries Institute in Olsztyn, 32-640, Zator, Poland.
authors.forename: Jerzy
authors.initials: J
authors.lastname: Adamek
authors.affiliation: Institute of Infectology, Friedrich-Loeffler-Institut, Südufer 10, 17498, Greifswald-Insel Riems, Germany.
authors.forename: Sven M
authors.initials: SM
authors.lastname: Bergmann
authors.affiliation: Fish Disease Research Unit, Institute for Parasitology, University of Veterinary Medicine, Bünteweg 17, 30559, Hannover, Germany.
authors.forename: Dieter
authors.initials: D
authors.lastname: Steinhagen
mesh_terms: D000818:Animals; D017756:Aquaculture / Q000379:methods; D002347:Carps / Q000821:virology*; D005260:Female; D005393:Fish Diseases / Q000821:virology*; D005880:Gills / Q000821:virology; D008297:Male; D011212:Poxviridae; D011213:Poxviridae Infections / Q000662:veterinary* / Q000821:virology; D012867:Skin / Q000821:virology