苏格兰沿海水域大西洋鲑中美洲异尖线虫第三期幼虫（L3）的感染强度增加。
Increasing intensities of Anisakis simplex third-stage larvae (L3) in Atlantic salmon of coastal waters of Scotland.
机构信息
School of Applied Sciences, Edinburgh Napier University, Edinburgh, EH11 4BN, Scotland.
Animal, Rural and Environmental Sciences, Nottingham Trent University, Southwell, NG25 0QF, UK.
出版信息
Parasit Vectors. 2020 Feb 12;13(1):62. doi: 10.1186/s13071-020-3942-5.
BACKGROUND
Red Vent Syndrome (RVS), a haemorrhagic inflammation of the vent region in Atlantic salmon, is associated with high abundance of Anisakis simplex (s.s.) third-stage larvae (L3) in the vent region. Despite evidence suggesting that increasing A. simplex (s.s.) intensity is a causative factor in RVS aetiology, the definitive cause remains unclear.
METHODS
A total of 117 Atlantic salmon were sampled from commercial fisheries on the East, West, and North coasts of Scotland and examined for ascaridoid parasites. Genetic identification of a subsample of Anisakis larvae was performed using the internal transcribed spacer (ITS) region of ribosomal DNA. To assess the extent of differentiation of feeding grounds and dietary composition, stable isotope analysis of carbon and nitrogen was carried out on Atlantic salmon muscle tissue.
RESULTS
In the present study, the obtained ITS rDNA sequences matched A. simplex (s.s.) sequences deposited in GenBank at 99-100%. Not all isolated larvae (n = 30,406) were genetically identified. Therefore, the morphotype found in this study is referred to as A. simplex (sensu lato). Anisakis simplex (s.l.) was the most prevalent (100%) nematode with the highest mean intensity (259.9 ± 197.3), in comparison to Hysterothylacium aduncum (66.7%, 6.4 ± 10.2) and Pseudoterranova decipiens (s.l.) (14.5%, 1.4 ± 0.6). The mean intensity of A. simplex (s.l.) represents a four-fold increase compared to published data (63.6 ± 31.9) from salmon captured in Scotland in 2009. Significant positive correlations between A. simplex (s.l.) larvae intensities from the body and the vent suggest that they play a role in the emergence of RVS. The lack of a significant variation in stable isotope ratios of Atlantic salmon indicates that diet or feeding ground are not driving regional differences in A. simplex (s.l.) intensities.
CONCLUSIONS
This paper presents the most recent survey for ascaridoid parasites of wild Atlantic salmon from three coastal regions in Scotland. A significant rise in A. simplex (s.l.) intensity could potentially increase both natural mortality rates of Atlantic salmon and possible risks for salmon consumers due to the known zoonotic role of A. simplex (s.s.) and A. pegreffii within the A. simplex (s.l.) species complex.
背景
红斑综合征（RVS）是大西洋鲑鱼腹区出血性炎症，与腹区高丰度的 Anisakis simplex（s.s.）第三期幼虫（L3）有关。尽管有证据表明，Anisakis simplex（s.s.）强度的增加是 RVS 病因学的一个致病因素，但确切原因仍不清楚。
方法
从苏格兰东、西、北海岸的商业渔业中采集了 117 条大西洋鲑鱼样本，检查了它们的ascaridoid 寄生虫。使用核糖体 DNA 的内部转录间隔区（ITS）对亚组 Anisakis 幼虫进行了遗传鉴定。为了评估摄食区和饮食成分的分化程度，对大西洋鲑鱼肌肉组织进行了碳和氮的稳定同位素分析。
结果
在本研究中，获得的 ITS rDNA 序列与 GenBank 中 99-100%的 Anisakis simplex（s.s.）序列匹配。并非所有分离的幼虫（n=30406）都进行了遗传鉴定。因此，本研究中发现的形态型被称为 Anisakis simplex（sensu lato）。Anisakis simplex（s.l.）是最普遍（100%）的线虫，平均强度最高（259.9±197.3），而与 Hysterothylacium aduncum（66.7%，6.4±10.2）和 Pseudoterranova decipiens（s.l.）（14.5%，1.4±0.6）相比。与 2009 年苏格兰捕获的鲑鱼的已发表数据（63.6±31.9）相比，Anisakis simplex（s.l.）的平均强度增加了四倍。从鱼体和腹区分离出的 Anisakis simplex（s.l.）幼虫的强度之间存在显著的正相关关系，这表明它们在 RVS 的出现中起作用。大西洋鲑鱼稳定同位素比值无显著变化表明，饮食或摄食区并不是导致 Anisakis simplex（s.l.）强度在区域间存在差异的原因。
结论
本文介绍了苏格兰三个沿海地区野生大西洋鲑鱼ascaridoid 寄生虫的最新调查结果。Anisakis simplex（s.l.）强度的显著增加可能会增加大西洋鲑鱼的自然死亡率，并可能由于 Anisakis simplex（s.s.）和 Anisakis pegreffii 在 Anisakis simplex（s.l.）种复合体中的已知人畜共患作用而对鲑鱼消费者造成潜在风险。
Zotero 插件