García-Vásquez Adriana, Razo-Mendivil Ulises, Rubio-Godoy Miguel
Instituto de Ecología, A.C., Red de Biología Evolutiva, km 2.5 ant. Carretera a Coatepec, El Haya, Xalapa, Veracruz 91070, Mexico.
Vet Parasitol. 2017 Feb 15;235:37-40. doi: 10.1016/j.vetpar.2017.01.014. Epub 2017 Jan 15.
As part of ongoing surveys of the gyrodactylid parasite fauna of freshwater fishes in Mexico, we recorded the infection of three species of poeciliids (Poecilia mexicana, Poeciliopsis gracilis, and Pseudoxiphophorus bimaculatus [syn.=Heterandria bimaculata]) with Gyrodactylus cichlidarum, a monogenean parasite of cichlid fishes, which has been co-introduced globally with its translocated, African "tilapia" hosts. This tilapia pathogen was found on poeciliid fishes both within their native distribution range in the Gulf of Mexico slope, as well as on invasive species artificially introduced to the Mexican highlands, to rivers draining into the Pacific Ocean. Identity of G. cichlidarum was confirmed by morphological and molecular analyses. Prevalence and abundance of infection were low, but this is the first record of G. cichlidarum infecting poeciliids (Cyprinodontiformes), which are distantly related to this parasite's primary cichlid fish hosts (Perciformes). This study provides evidence that G. cichlidarum, a recognized pathogen which has been co-introduced globally with its cichlid fish hosts for aquacultural purposes, is able to infect non-related poeciliid fishes inhabiting water bodies adjacent to tilapia farms, thereby potentially increasing its ability to disperse between farms and different river basins. It is of particular concern that G. cichlidarum was found on poeciliids, as these invasive fishes have been introduced worldwide and could act as carriers for this parasite known to induce significant mortality of farmed tilapias - globally, the second most important freshwater aquaculture fish group, after the carps.
作为墨西哥淡水鱼三代虫寄生虫区系持续调查的一部分，我们记录了三种食蚊鱼（墨西哥食蚊鱼、细纹食蚊鱼和双斑假剑尾鱼[同物异名=双斑异齿鳉]）感染丽鱼三代虫的情况，丽鱼三代虫是丽鱼科鱼类的一种单殖吸虫寄生虫，已与其迁移的非洲“罗非鱼”宿主一同被引入全球。这种罗非鱼病原体在墨西哥湾沿岸食蚊鱼的原生分布范围内以及人工引入墨西哥高地、流入太平洋的河流中的入侵物种身上均有发现。通过形态学和分子分析确认了丽鱼三代虫的身份。感染率和感染强度较低，但这是丽鱼三代虫感染食蚊鱼（鲤齿目）的首次记录，食蚊鱼与这种寄生虫的主要宿主丽鱼科鱼类（鲈形目）亲缘关系较远。这项研究提供了证据，表明丽鱼三代虫作为一种已因其丽鱼科鱼类宿主而在全球范围内被引入用于水产养殖的公认病原体，能够感染栖息在罗非鱼养殖场附近水体中的非相关食蚊鱼，从而可能增强其在养殖场和不同流域之间传播的能力。特别令人担忧的是，在食蚊鱼身上发现了丽鱼三代虫，因为这些入侵鱼类已被引入世界各地，可能会成为这种已知会导致养殖罗非鱼大量死亡的寄生虫的携带者——在全球范围内，罗非鱼是仅次于鲤鱼的第二重要淡水养殖鱼类群体。
