Search

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. [ABSTRACT FROM AUTHOR]

Endangered wood bison (Bison bison athabascae) is the largest terrestrial mammal in the American continent. Animal health is an important issue in their conservation, and Sarcocystis cruzi may be a cause of clinical disease in Bovidae. Hearts of eight wood bison from Alaska, USA were examined for sarcocysts by histology, transmission electron microscopy, pepsin digestion, and molecularly. Sarcocystis bradyzoites were found in pepsin digests of all eight and sarcocysts were found in histologic sections of myocardium of four bison. Sarcocysts were thin-walled and ultrastructurally consistent with S. cruzi. Characterization of DNA obtained from lysis of pepsin liberated bradyzoites by PCR-RFLP and subsequent phylogenetic analyses matched with that previously reported for S. cruzi infecting cattle in the USA. Collectively, data indicate that wood bison is a natural intermediate host for S. cruzi., (Published by Elsevier B.V.)