Bain N, Gregory A, Raynard R S
FRS Marine Laboratory, Aberdeen, UK.
J Fish Dis. 2008 Jan;31(1):37-47. doi: 10.1111/j.1365-2761.2007.00864.x.
Infectious pancreatic necrosis (IPN) is a highly contagious disease of young salmonid fish, and is one of the most serious economic diseases in aquaculture. In Scotland, an increase in IPN virus (IPNV) outbreaks in seawater Atlantic salmon, Salmo salar, has been reported in recent years. The aim of this study was to analyse the VP2 gene from recent IPNV isolates from Scotland, to determine whether there are epidemiological links between IPNV isolates from farms (13), wild fish (17) and the environment (6) in order to investigate potential wild and farmed fish interactions. Comparison of the nucleotide sequence of the VP2 gene revealed that 34 of 36 isolates were 97.1-100% similar and the deduced amino acid sequences showed 97-100% identity. Two isolates from wild fish exhibited the most divergence at 85-87.3% similarity to the other isolates at the nucleotide level and 88.2-90.8% identity at the deduced amino acid level. Phylogenetic analyses revealed that 34 of 36 of the isolates from Scotland were genetically closely related to the A2 (Sp) serotype of IPNV. The two wild isolates from seatrout, Salmo trutta, and flounder, Platichthys flesus, were most closely related to the European A5 (Te) serotype. This study represents a comprehensive IPNV phylogenetic study that indicates that there are closely related or identical isolates in circulation in the marine environment, which adds evidence that disease interactions between wild and farmed fish may occur. This type of analysis is a useful tool in the management and control of fish diseases because it can assist in the identification of epidemiological links and highlight potential risks to aquaculture.
传染性胰腺坏死（IPN）是幼鲑科鱼类的一种高度传染性疾病，也是水产养殖中最严重的经济疾病之一。在苏格兰，近年来海水大西洋鲑（Salmo salar）中IPN病毒（IPNV）爆发有所增加。本研究的目的是分析来自苏格兰近期IPNV分离株的VP2基因，以确定来自养殖场（13个）、野生鱼类（17个）和环境（6个）的IPNV分离株之间是否存在流行病学联系，从而调查野生和养殖鱼类之间的潜在相互作用。VP2基因核苷酸序列的比较显示，36个分离株中有34个相似度为97.1 - 100%，推导的氨基酸序列显示同一性为97 - 100%。来自野生鱼类的两个分离株在核苷酸水平上与其他分离株的相似度为85 - 87.3%，在推导氨基酸水平上的同一性为88.2 - 90.8%，差异最大。系统发育分析表明，来自苏格兰的36个分离株中有34个在基因上与IPNV的A2（Sp）血清型密切相关。来自海鳟（Salmo trutta）和比目鱼（Platichthys flesus）的两个野生分离株与欧洲A5（Te）血清型关系最为密切。本研究是一项全面的IPNV系统发育研究，表明海洋环境中存在密切相关或相同的分离株，这进一步证明了野生和养殖鱼类之间可能发生疾病相互作用。这种分析类型是鱼类疾病管理和控制中的一种有用工具，因为它有助于识别流行病学联系并突出水产养殖的潜在风险。
