Calero-Bernal Rafael, Cerqueira-Cézar Camila K, Verma Shiv Kumar, Mowery Joseph, Carmena David, Beckmen Kimberlee, Dubey Jitender P
Agricultural Research Service, Beltsville Agricultural Research Center, Animal Parasitic Diseases Laboratory, United States Department of Agriculture, Building 1001, Beltsville, MD, 20705-2350, USA.
Agricultural Research Service, Beltsville Agricultural Research Center, Electron and Confocal Microscopy Unit, United States Department of Agriculture, Building 12, Beltsville, MD, 20705-2350, USA.
Parasitol Res. 2016 Jul;115(7):2893-7. doi: 10.1007/s00436-016-5067-5. Epub 2016 Apr 26.
Sarcocystis sarcocysts are common in muscles of herbivores but are rare in muscles of carnivores. Here, we report sarcocysts in the muscles of a gray wolf (Canis lupus) from Alaska, USA, for the first time. Sarcocysts extracted from the tongue of the wolf were up to 900 μm long and slender and appeared to have a relatively thin wall by light microscope. By transmission electron microscopy, the sarcocyst wall most closely resembled "type 9c," and had a wavy parasitophorous vacuolar membrane folded as pleomorphic villar protrusions (vp), with anastomoses of tips. The vp and the ground substance (gs) layer were smooth without tubules or granules. The gs was up to 2.0 μm thick. The total width of the wall including vp and the gs was 3.5 μm. The vp were up to 1.5 μm long. Mature sarcocysts contained numerous bradyzoites and few metrocytes. The bradyzoites were 9.5 μm long and 1.5 μm wide, and contained all organelles found in Sarcocystis bradyzoites with at least two rhoptries. Molecular characterization showed the highest identity for 18S rRNA, 28S rRNA, ITS-1, and cox1 sequences of Sarcocystis arctica of the Arctic fox (Vulpes lagopus) from Norway. The ultrastructure of S. arctica from the fox is unknown. Here, we provide ultrastructure of S. arctica from the Alaskan wolf for the first time. The definitive host of S. arctica remains unknown.
肉孢子虫囊在食草动物的肌肉中很常见，但在食肉动物的肌肉中很少见。在此，我们首次报告了来自美国阿拉斯加的一只灰狼（Canis lupus）肌肉中的肉孢子虫囊。从狼的舌头中提取的肉孢子虫囊长达900μm，细长，在光学显微镜下似乎有相对较薄的壁。通过透射电子显微镜观察，肉孢子虫囊壁最接近“9c型”，有一个波浪状的寄生泡膜，折叠成多形性的绒毛状突起（vp），顶端相互吻合。vp和基质（gs）层光滑，没有小管或颗粒。gs层厚度达2.0μm。包括vp和gs的壁的总宽度为3.5μm。vp长达1.5μm。成熟的肉孢子虫囊含有许多缓殖子和少量母细胞。缓殖子长9.5μm，宽1.5μm，含有肉孢子虫缓殖子中发现的所有细胞器，至少有两个棒状体。分子特征显示，其18S rRNA、28S rRNA、ITS-1和cox1序列与来自挪威的北极狐（Vulpes lagopus）的北极肉孢子虫的序列具有最高的同源性。来自狐狸的北极肉孢子虫的超微结构尚不清楚。在此，我们首次提供了来自阿拉斯加狼的北极肉孢子虫的超微结构。北极肉孢子虫的终末宿主仍然未知。
