title: Early migration of Sarcocystis neurona in ponies fed sporocysts.
abstract: Sarcocystis neurona is the most important cause of equine protozoal myeloencephalitis (EPM), a neurologic disease of the horse. In the present work, the kinetics of S. neurona invasion is determined in the equine model. Six ponies were orally inoculated with 250 x 10(6) S. neurona sporocysts via nasogastric intubation and killed on days 1, 2, 3, 5, 7, and 9 postinoculation (PI). At necropsy, tissue samples were examined for S. neurona infection. The parasite was isolated from the mesenteric lymph nodes at 1, 2, and 7 days PI; the liver at 2, 5, and 7 days PI; and the lungs at 5, 7, and 9 days PI by bioassays in interferon gamma gene knock out mice (KO) and from cell culture. Microscopic lesions consistent with an EPM infection were observed in brain and spinal cord of ponies killed 7 and 9 days PI. Results suggest that S. neurona disseminates quickly in tissue of naive ponies.
authors.affiliation: Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio 43210-1092, USA.
authors.forename: E
authors.initials: E
authors.lastname: Elitsur
authors.forename: A E
authors.initials: AE
authors.lastname: Marsh
authors.forename: S M
authors.initials: SM
authors.lastname: Reed
authors.forename: J P
authors.initials: JP
authors.lastname: Dubey
authors.forename: M J
authors.initials: MJ
authors.lastname: Oglesbee
authors.forename: J E
authors.initials: JE
authors.lastname: Murphy
authors.forename: W J A
authors.initials: WJ
authors.lastname: Saville
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D001921:Brain / Q000473:pathology; D004679:Encephalomyelitis / Q000469:parasitology / Q000662:veterinary*; D005260:Female; D041981:Gastrointestinal Tract / Q000469:parasitology; D006734:Horse Diseases / Q000469:parasitology*; D006736:Horses; D007371:Interferon-gamma / Q000235:genetics; D008099:Liver / Q000469:parasitology; D008168:Lung / Q000469:parasitology; D008198:Lymph Nodes / Q000469:parasitology; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D033661:Oocysts / Q000502:physiology*; D012522:Sarcocystis / Q000302:isolation & purification / Q000472:pathogenicity* / Q000502:physiology*; D012523:Sarcocystosis / Q000469:parasitology / Q000662:veterinary*; D013116:Spinal Cord / Q000473:pathology
chemical_list: D000913:Antibodies, Protozoan; D007371:Interferon-gamma