McDonald Brandon M, Cove Michael V, Ruder Mark G, Yabsley Michael J, Garrett Kayla B, Thompson Alec T, Nemeth Nicole M, Dixon Jeremy D, Lashley Marcus A
Department of Wildlife Ecology and Conservation, University of Florida, 1745 McCarty Drive, Gainesville, Florida 32611, USA.
North Carolina Museum of Natural Sciences, 11 W. Jones St., Raleigh, North Carolina, 27601, USA.
J Wildl Dis. 2025 Jan 1;61(1):180-185. doi: 10.7589/JWD-D-24-00041.
We collected and screened black rats (Rattus rattus) in Key Largo, Florida, USA, to determine the potential role of disease or parasites in the collapse of the local population. Rats appeared healthy, but 94% (n=15/16) tested positive for Sarcocystis sp. The partial 18S rRNA gene sequence was 98.7-99.7% similar to a strain of Sarcocystis zuoi that is now considered a strain of the newly described Sarcocystis kani within the larger S. zuoi species complex that contains numerous new species. These Sarcocystis spp. use Asian snakes as definitive hosts and rodents, shrews, or tree shrews as intermediate hosts. Pythons are the definitive host for several Sarcocystis spp. in Asia, including a related parasite (Sarcocystis singaporensis) that has been used as a biologic control agent for Rattus spp. in southeast Asia. It is probable that increasing numbers of invasive Burmese pythons (Python bivittatus) in the Florida Keys are contributing to the spread of this parasite in addition to imposing predation pressure on both rodents and native snakes. As such, further surveillance and molecular and morphologic characterization of parasites from rodents and snakes in south Florida should be prioritized.
我们在美国佛罗里达州基拉戈捕获并检测了黑家鼠（Rattus rattus），以确定疾病或寄生虫在当地种群数量减少中可能起到的作用。这些老鼠看似健康，但94%（n = 15/16）的个体对肉孢子虫属（Sarcocystis sp.）检测呈阳性。其18S rRNA基因部分序列与肉孢子虫左氏株（Sarcocystis zuoi）相似度为98.7 - 99.7%，而该株现在被认为是在包含众多新物种的更大的左氏肉孢子虫物种复合体中新描述的卡氏肉孢子虫（Sarcocystis kani）的一个株系。这些肉孢子虫物种以亚洲蛇类作为终末宿主，以啮齿动物、鼩鼱或树鼩作为中间宿主。蟒蛇是亚洲几种肉孢子虫物种的终末宿主，包括一种相关寄生虫（新加坡肉孢子虫，Sarcocystis singaporensis），该寄生虫已被用作东南亚鼠类的生物防治剂。除了对啮齿动物和本地蛇类施加捕食压力外，佛罗里达群岛入侵缅甸蟒（Python bivittatus）数量的增加很可能也促使了这种寄生虫的传播。因此，应优先对佛罗里达州南部啮齿动物和蛇类的寄生虫进行进一步监测以及分子和形态学特征分析。
