Korsnes Kjetil, Karlsbakk Egil, Nylund Are, Nerland Audun Helge
Faculty of Biosciences and Aquaculture, University of Nordland, 8049 Bodø, Norway.
Dis Aquat Organ. 2012 May 15;99(1):13-21. doi: 10.3354/dao02454.
Experimental horizontal transmission of nervous necrosis virus (NNV) originating from halibut Hippoglossus hippoglossus was studied through cohabitation of intraperitoneally (i.p.) injected fish with uninfected fish for 125 d. The experimental groups consisted of i.p. injected turbot Scophthalmus maximus or i.p. injected Atlantic salmon Salmo salar with turbot, salmon or Atlantic cod Gadus morhua cohabitants. The initial weights were cod 10 g, salmon 40 g and turbot 3 g. NNV was detected in brain, eye and spleen by real-time reverse transcriptase PCR (qRT-PCR) in cod cohabitated with i.p. injected turbot after 90 and 125 d, suggesting NNV infection was transmitted horizontally from the turbot to cod. NNV was not detected in salmon that were cohabitated with i.p. challenged turbot or salmon. This study shows that NNV strains belonging to the Barfin Flounder Nervous Necrosis Virus (BFNNV) clade may be transmitted from halibut to cod via water. Hence there is a potential risk of horizontal transmission of the virus from farmed halibut to farmed and wild cod. The lack of detection of NNV in cohabitant salmon suggests that this fish species is less susceptible than cod, or not susceptible, to horizontal NNV transmission. This result might be influenced by the size of salmon, viral load in i.p. injected cohabitants or insufficient duration of the experiment.
通过将腹腔注射神经坏死病毒（NNV）的大比目鱼（Hippoglossus hippoglossus）与未感染的鱼同居125天，研究了源自大比目鱼的神经坏死病毒的实验性水平传播。实验组包括腹腔注射的大菱鲆（Scophthalmus maximus）或腹腔注射的大西洋鲑（Salmo salar），它们分别与大菱鲆、鲑鱼或大西洋鳕鱼（Gadus morhua）同居。初始体重分别为鳕鱼10克、鲑鱼40克和大菱鲆3克。在与腹腔注射大菱鲆同居的鳕鱼中，通过实时逆转录酶PCR（qRT-PCR）在90天和125天后在脑、眼和脾脏中检测到NNV，这表明NNV感染从大菱鲆水平传播到了鳕鱼。在与腹腔注射NNV的大菱鲆或鲑鱼同居的鲑鱼中未检测到NNV。这项研究表明，属于条石鲷神经坏死病毒（BFNNV）进化枝的NNV毒株可能通过水从大比目鱼传播到鳕鱼。因此，该病毒存在从养殖大比目鱼水平传播到养殖和野生鳕鱼的潜在风险。在同居的鲑鱼中未检测到NNV，这表明该鱼类对NNV水平传播的易感性低于鳕鱼，或者不易感。这一结果可能受鲑鱼大小、腹腔注射同居者的病毒载量或实验持续时间不足的影响。
