White Carson F H, Gray Michelle A, Kidd Karen A, Duffy Michael S, Lento Jennifer, Monk Wendy A
Canadian Rivers Institute, University of New Brunswick, Fredericton, New Brunswick, E3B 5A3, Canada.
Faculty of Forestry and Environmental Management, University of New Brunswick, Fredericton, New Brunswick, E3B 5A3, Canada.
J Aquat Anim Health. 2020 Mar;32(1):11-20. doi: 10.1002/aah.10091. Epub 2020 Jan 21.
Parasites can compromise the health and fitness of individual fish, and it is important to generate baseline information that can then be used to document changes in the abundance and distribution of potentially pathogenic parasites. The ectoparasitic copepod Salmincola edwardsii was assessed with respect to prevalence (percentage of infected fish per site), infection intensity (number of parasites per infected fish), and attachment location on Brook Trout Salvelinus fontinalis in northwest New Brunswick, Canada. Ten sample sites were assessed, with six sites on two streams in the Quisibis River basin and four sites on three streams in the Restigouche River basin. Parasite species identity was supported by 100% sequence identity with S. edwardsii in a variable region within 28S rDNA. The prevalence of fish infected per site ranged from 19.0% to 79.6%, with an overall prevalence of 48.5 ± 19.1% (mean ± SD) per site. Mean infection intensity was 1.5 ± 0.9 copepods/fish (range = 1-7), with parasites almost exclusively surrounding the dorsal fin and/or adipose fin (97.6%). There was no influence of trout age-class on parasite prevalence. Some fish presented with fin erosion at the site of parasite attachment (12.5%), and 6.2% also presented with hyperplastic skin lesions where no parasites were observed, that could be misinterpreted as secondary bacterial or fungal infections. Skin and fin damage were significantly more common when fish were infected with three or more individual parasites. The pathogenic potential of this parasite makes its presence noteworthy as a risk to salmonids that are both recreationally and ecologically important.
寄生虫会损害个体鱼类的健康和体质，因此生成基线信息非常重要，这些信息随后可用于记录潜在致病寄生虫的丰度和分布变化。对加拿大新不伦瑞克省西北部溪红点鲑（Salvelinus fontinalis）身上的外寄生桡足类寄生虫爱德华兹鲑虱（Salmincola edwardsii）进行了患病率（每个采样点受感染鱼类的百分比）、感染强度（每条受感染鱼身上的寄生虫数量）以及附着位置的评估。共评估了10个采样点，其中6个位于基西比斯河流域两条溪流的6个地点，4个位于雷斯蒂古什河流域三条溪流的4个地点。在28S rDNA的一个可变区域内，寄生虫物种鉴定结果显示与爱德华兹鲑虱的序列一致性达100%。每个采样点受感染鱼类的患病率在19.0%至79.6%之间，每个采样点的总体患病率为48.5±19.1%（平均值±标准差）。平均感染强度为1.5±0.9只桡足类/鱼（范围为1至7只），寄生虫几乎全部集中在背鳍和/或脂鳍周围（97.6%）。鳟鱼年龄组对寄生虫患病率没有影响。一些鱼在寄生虫附着部位出现鳍侵蚀（12.5%），6.2%的鱼在未观察到寄生虫的部位出现增生性皮肤损伤，这可能会被误诊为继发性细菌或真菌感染。当鱼感染三只或更多个体寄生虫时，皮肤和鳍损伤明显更为常见。这种寄生虫的致病潜力使其成为对具有娱乐和生态重要性的鲑科鱼类的一个值得关注的风险。
