Centre Québécois sur la Santé des Animaux Sauvages-Canadian Cooperative Wildlife Health Centre, Université de Montréal, St Hyacinthe, QC, Canada.
J Fish Dis. 2011 Jun;34(6):475-81. doi: 10.1111/j.1365-2761.2011.01258.x.
The striped bass, Morone saxatilis (Walbaum), once represented an important resource for fisheries in the St Lawrence River (Quebec, Canada). A restoration programme, involving captive propagation, was implemented with the objective of restocking the population, which had disappeared in the late 1960s. An unusually high rate of mortality was observed during the winter of 2006 in captive-raised fingerlings that were originally collected from the Miramichi River (New Brunswick, Canada) the previous summer. Post-mortem examinations revealed extensive granulomatous and hyperplastic peritonitis associated with numerous nematodes of the genus Philometra. Given the severity of the lesions, high intensity of infection by Philometra sp. was presumed to be the primary factor in the unusual mortalities reported that winter. Observations suggest that this nematode, which was acquired in the wild, cannot establish itself in a captive environment, most likely because of the absence of the obligate intermediate host. Examination of archived specimens of striped bass showed that this parasite was probably present in the St Lawrence River population prior to its extirpation. Consequently, the introduction of infected fish into this ecosystem should not be a concern. Nevertheless, infection-related mortalities of fingerlings might affect dynamics of wild striped bass populations.
条纹鲈，又称岩鲈（Morone saxatilis (Walbaum)），曾是圣劳伦斯河（加拿大魁北克省）渔业的重要资源。为了恢复 20 世纪 60 年代末消失的种群，实施了一项涉及人工养殖的恢复计划。然而，2006 年冬季，在去年夏天从米拉米奇河（加拿大新不伦瑞克省）采集的人工养殖鱼苗中，出现了异常高的死亡率。剖检结果显示，大量的 Philometra 属线虫引起了广泛的肉芽肿和增生性腹膜炎。鉴于病变的严重程度，推测 Philometra sp. 的高感染强度是导致当年冬季异常死亡的主要因素。观察表明，这种在野外获得的线虫无法在人工养殖环境中生存，这很可能是由于缺乏专性中间宿主。对条纹鲈的存档标本进行检查表明，这种寄生虫可能在其灭绝之前就存在于圣劳伦斯河种群中。因此，将受感染的鱼类引入该生态系统不应成为关注的问题。然而，与感染相关的鱼苗死亡率可能会影响野生条纹鲈种群的动态。
