Ramírez-Cañas Sara Angélica, George-Nascimento Mario, García-Prieto Luis, Mata-López Rosario
1 Departamento de Biología Evolutiva, Facultad de Ciencias, Universidad Nacional Autónoma de México. Avenida Universidad 3000, Ciudad Universitaria, C.P. 04510; Mexico City, Mexico.
2 Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Apartado 70-153, C.P. 04510, Mexico City, Mexico.
J Parasitol. 2019 Aug;105(4):624-629.
Studies on helminth communities associated with didelphids are scarce; the majority of works have focused at taxonomic level. To increase the ecological knowledge of these host-parasite associations, during March (dry season) of 3 consecutive years (2013-2015) a total of 49 adults of the gray four-eyed opossum () was collected in the Neotropical portion of Mexico (Agua Fría, Chiapas State) and examined for helminths. The main objectives of this study were to describe the infra- and component communities of helminths associated with and to compare the helminth fauna of the Mexican population of this host species with those studied in French Guiana and in other Mexican terrestrial didelphids. The helminthological record of this host consisted of 12 species: 7 taxa of Nematoda, 3 of Trematoda, 1 Cestoda, and 1 Acanthocephala. Eight of the 12 taxa have been previously recorded in Didelphidae and 4 represent accidental infections ( sp., , and Acanthocephala gen. sp.). Diet of hosts is the main structuring factor of the communities (92% of the helminth species were recruited through ingestion). Forty-eight hosts were parasitized by at least 1 helminth species; was the most prevalent and abundant species in the hosts sampled. No significant differences were found in global prevalence among the helminth species present in all samplings, considering host sex and year. The dominance exerted by led to low values of evenness and diversity at both community levels. No significant differences were observed in composition of helminth species among the 3 sampling years regarding sex. The results of our study showed changes in helminth abundance at infracommunity level; during the first sampling these changes are explained by species with direct life cycle ( sp. and ), whereas in last 2 surveys the explanation can be attributed to species with heteroxenous life cycles (particularly , , and ). Thirty-three percent of the helminth species recorded in in Agua Fría is shared with the other 2 terrestrial species of didelphids sampled in different sites of Mexico: and . In contrast, samples from French Guiana and Agua Fría, differ in terms of helminth fauna, confirming that the helminth communities of opossum species inhabiting the same locality show higher levels of taxonomic similarity than communities of conspecific marsupials allopatrically distributed.
关于与负鼠相关的蠕虫群落的研究很少；大多数研究都集中在分类学层面。为了增加对这些宿主 - 寄生虫关联的生态学认识，在连续三年（2013 - 2015年）的3月（旱季），在墨西哥的新热带地区（恰帕斯州阿瓜弗里亚）共收集了49只成年灰四眼负鼠（ ），并对其进行蠕虫检查。本研究的主要目的是描述与 相关的蠕虫的亚群落和组成群落，并将该宿主物种的墨西哥种群的蠕虫动物群与在法属圭亚那和其他墨西哥陆生负鼠中研究的进行比较。该宿主的蠕虫学记录包括12个物种：7个线虫类群、3个吸虫类群、1个绦虫类群和1个棘头虫类群。这12个类群中有8个先前已在负鼠科中记录，4个代表偶然感染（ 属种、 、 和棘头虫属种）。宿主的饮食是群落的主要构建因素（92%的蠕虫物种是通过摄食获得的）。48只宿主被至少1种蠕虫物种寄生； 在采样宿主中是最普遍和丰富的物种。考虑到宿主性别和年份，在所有采样中存在的蠕虫物种的总体患病率没有发现显著差异。 所表现出的优势导致两个群落层面的均匀度和多样性值较低。在三个采样年份中，关于性别，蠕虫物种的组成没有观察到显著差异。我们的研究结果表明，在亚群落层面蠕虫丰度存在变化；在第一次采样期间，这些变化由具有直接生命周期的物种（ 属种和 ）解释，而在最后两次调查中，解释可归因于具有异寄主生命周期的物种（特别是 、 和 ）。在阿瓜弗里亚的 中记录的33%的蠕虫物种与在墨西哥不同地点采样的其他两种陆生负鼠物种（ 和 ）共有。相比之下，来自法属圭亚那和阿瓜弗里亚的样本在蠕虫动物群方面存在差异，证实了居住在同一地点的负鼠物种的蠕虫群落比异域分布的同种有袋动物群落表现出更高水平的分类相似性。
