Department of Public Health and Infectious Diseases, Section of Parasitology, Sapienza University of Rome, Italy; Department of Ecological and Biological Sciences (DEB), Tuscia University, Viale dell'Università, snc, 01100 Viterbo, Italy.
Department of Veterinary Medicine and Animal Production, University of Naples "Federico II", Via F. Delpino 1, 80137 Napoli, Italy.
Int J Food Microbiol. 2015 Apr 2;198:1-8. doi: 10.1016/j.ijfoodmicro.2014.11.019. Epub 2014 Nov 29.
The consumption of the hake Merluccius merluccius is widespread in European countries, where this fish has a high commercial value. To date, different larval species of Anisakis have been identified as parasites in M. merluccius from European waters, Anisakis pegreffii and Anisakis simplex (s. s.) being the two most common. The aim of the study is to present data on the occurrence of Anisakis spp. larvae in the viscera and flesh of M. merluccius. Consequently, the distribution and infection rates of different species of Anisakis in different sites (viscera, and dorsal and ventral fillets) were investigated in hake caught in the central Tyrrhenian Sea (FAO 37.1.3) and the NE Atlantic Ocean (FAO 27 IXa). A sample of N=65 fish individuals (length>26 cm) was examined parasitologically from each fishing ground. The fillets were examined using the pepsin digestion method. A large number (1310) of Anisakis specimens were identified by multilocus allozyme electrophoresis (MAE) and mtDNA cox2 sequence analysis; among these, 814 larvae corresponded to A. simplex (s. s.) and 476 to A. pegreffii. They were found to infect both the flesh and the viscera. The two species co-infected the same individual fish (both in the viscera and in the flesh) from the FAO 27 area, whereas only A. pegreffii was found in hake from the Tyrrhenian Sea. The average parasite burden of A. pegreffii in hake from the Tyrrhenian Sea was significantly lower to that observed from hake off the Atlantic coast of Spain, both in prevalence and in abundance. In addition, whereas no significant difference in overall prevalence values was recorded between the two Anisakis species in the viscera of the FAO 27 sample, significant differences were found in the abundance levels observed between these species in the flesh, with A. simplex (s. s.) exhibiting significantly higher levels than that observed for A. pegreffii (p<0.001). Given that the pathogenic role in relation to man is known for these two species of Anisakis, both the flesh inspection and the infection rates of the different anisakid species assume particular importance in terms of assessing the risk they pose to humans.
欧洲国家广泛食用无须鳕 Merluccius merluccius，这种鱼具有很高的商业价值。迄今为止，不同的 Anisakis 幼虫种已被确定为来自欧洲水域的 M. merluccius 的寄生虫，Anisakis pegreffii 和 Anisakis simplex (s. s.) 是两种最常见的寄生虫。本研究旨在介绍 Anisakis spp.幼虫在 M. merluccius 内脏和肌肉中的存在数据。因此，研究了在中地中海水域（粮农组织 37.1.3）和东北大西洋（粮农组织 27IXa）捕获的无须鳕不同部位（内脏、背部和腹部鱼片）中不同种 Anisakis 的分布和感染率。从每个渔区随机抽取了 65 条长度大于 26 厘米的个体进行寄生虫学检查。使用胃蛋白酶消化法检查鱼片。通过多位点同工酶电泳（MAE）和 mtDNA cox2 序列分析鉴定了大量（1310 个）Anisakis 标本；其中，814 个幼虫对应于 A. simplex (s. s.)，476 个幼虫对应于 A. pegreffii。它们被发现同时感染肌肉和内脏。这两个种在 FAO 27 区的同一尾鱼的内脏和肌肉中都有共感染，而在来自第勒尼安海的无须鳕中只发现了 A. pegreffii。第勒尼安海无须鳕中 A. pegreffii 的寄生虫负荷平均明显低于西班牙大西洋沿岸无须鳕中的寄生虫负荷，无论是在流行率还是丰度方面。此外，尽管在 FAO 27 样本的内脏中，两种 Anisakis 种的总体流行率值没有显著差异，但在肌肉中观察到的这些种的丰度水平存在显著差异，A. simplex (s. s.) 的水平明显高于 A. pegreffii（p<0.001）。鉴于这两种 Anisakis 种与人类有关的致病作用，肌肉检查和不同异尖线虫种的感染率在评估它们对人类构成的风险方面具有特别重要的意义。
