Vaschalde Paula J, Barolin Johann, Monje Lucas D, Flores Fernando S
Laboratorio de Ecología de Enfermedades, Instituto de Ciencias Veterinarias del Litoral (ICIVET-Litoral), Universidad Nacional del Litoral (UNL) / Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Esperanza, Santa Fe, Argentina.
Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral (UNL), Santa Fe, Argentina.
Exp Appl Acarol. 2024 Dec 13;94(1):12. doi: 10.1007/s10493-024-00983-8.
The aim of the study was to report the occurrence of Ixodes silvanus outside its distribution range, in the Chaco Serrano vegetation unit of the Chaco Phytogeographic Province, central Argentina. Ticks were collected from vegetation and on birds between November 2021 and December 2023. A possible seasonal activity was observed in the immature stages of I. silvanus, with larvae in autumn-winter and nymphs in spring-summer, consistent with a behavioral diapause. A total of 937 ticks were identified as I. silvanus and confirmed molecularly, 741 host-seeking and 196 parasitizing 49 passerine birds (of 9 species, 6 genera and 5 families). All host-seeking ticks were found in leaf litter in forests dominated by the invasive tree Ligustrum lucidum, suggesting a possible link between environmental changes and the establishment of I. silvanus in this region. The prevalence of I. silvanus on birds was 27.4%, with significant participation of the Turdus genus and new host associations documented. The findings suggest that I. silvanus may be expanding its range, potentially facilitated by environmental modifications, the movement of austral migratory birds (Turdus nigriceps, Synallaxis frontalis and Zonotrichia capensis), and the range expansion of other bird species (Turdus amaurochalinus, Turdus chiguanco and Turdus rufiventris). Therefore, I. silvanus may represent a biological invasion and a potential threat to wild bird populations as a vector of pathogenic microorganisms. Future studies are required to determine the implications this could have.
本研究的目的是报告在阿根廷中部查科植物地理省查科 Serrano 植被单元中，超出其分布范围出现的森林硬蜱。在 2021 年 11 月至 2023 年 12 月期间，从植被和鸟类身上采集蜱虫。观察到森林硬蜱未成熟阶段可能存在季节性活动，幼虫出现在秋冬季节，若虫出现在春夏季节，这与行为滞育一致。总共鉴定出 937 只森林硬蜱并通过分子手段予以确认，其中 741 只为寻找宿主的蜱虫，196 只为寄生在 49 只雀形目鸟类（9 个物种、6 个属和 5 个科）身上的蜱虫。所有寻找宿主的蜱虫均在以入侵树种女贞为主的森林落叶层中发现，这表明环境变化与该地区森林硬蜱的定殖之间可能存在联系。森林硬蜱在鸟类身上的感染率为 27.4%，记录到鸫属的显著参与以及新的宿主关联。研究结果表明，森林硬蜱可能正在扩大其分布范围，这可能受到环境变化、南方候鸟（黑头鸫、额部窜鸟和海角带鹀）的迁徙以及其他鸟类物种（黑喉鸫、棕背鸫和棕腹鸫）分布范围扩大的推动。因此，森林硬蜱可能代表一种生物入侵，并作为致病微生物的传播媒介对野生鸟类种群构成潜在威胁。需要未来的研究来确定这可能产生的影响。
