title: Ultrastructure of Frenkelia sp. from a Norwegian lemming in Finland.
abstract: An apparently healthy Norwegian lemming (Lemmus lemmus) caught in northern Finland was observed to have a whitish body 0.5 to 1.0 mm in diameter in the external layer of the cerebral cortex. By light microscopy a highly lobulated cyst of Frenkelia sp. was observed. By transmission electron microscopy lemmus) collected in the cyst wall was seen consisting of a parasitophorous vacuolar membrane, an underlying electron-dense layer and a granular layer. The membrane was only slightly convoluted. The protrusions of the cyst wall appeared round but were often not distinctive. A very thin septum divided the interior of the cyst into compartments packed with bradyzoites and maturing zoites. The bradyzoites were elongate measuring 5-8 x 1.5-2 microm. This is the first electron microscopical study of Frenkelia sp. from L. lemmus.
authors.affiliation: Department of Biology, University of California, San Diego, La Jolla 92093-0116, USA. Juha@biomail.ucsd.edu
authors.forename: J
authors.initials: J
authors.lastname: Laakkonen
authors.forename: H
authors.initials: H
authors.lastname: Henttonen
mesh_terms: D000818:Animals; D003411:Arvicolinae / Q000469:parasitology*; D001921:Brain / Q000469:parasitology* / Q000648:ultrastructure; D003048:Coccidiosis / Q000469:parasitology / Q000662:veterinary*; D021741:Eimeriida / Q000648:ultrastructure*; D005387:Finland; D008297:Male; D008854:Microscopy, Electron