title: Isolates of Sarcocystis falcatula-like organisms from South American opossums Didelphis marsupialis and Didelphis albiventris from São Paulo, Brazil.
abstract: Isolates of Sarcocystis falcatula-like organisms from South American opossums were characterized based on biological and morphological criteria. Sporocysts from intestinal scrapings of 1 Didelphis marsupialis and 8 Didelphis albiventris from São Paulo, Brazil, were fed to captive budgerigars (Melopsittacus undulatus). Budgerigars fed sporocysts from all 9 isolates became ill and S. falcatula-like schizonts were identified in sections of their lungs by immunohistochemical staining. Sarcocystis falcatula-like organisms were cultured from lungs of budgerigars fed sporocysts from D. marsupialis and from lungs of budgerigars fed sporocysts from 3 of 8 D. albiventris. The 33/54 locus amplified by polymerase chain reaction from culture-derived merozoites contained both a HinfI endonuclease recognition site previously suggested to diagnose S. falcatula and a DraI site thought to diagnosed S. neurona. Development of the isolate from D. marsupialis was studied in cell culture; its schizonts divided by endopolygeny, leaving a residual body. Morphological and genetic variation differentiated this Sarcocystis isolate originating in D. marsupialis from the Cornell I isolate of S. falcatula. This is the first report of a S. falcatula infection in the South American opossum, D. marsupialis.
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, Animal and Natural Resources Institute, Parasite Biology, Epidemiology and Systematics Laboratory, Beltsville, Maryland 20705-2350, USA. jdubey@anri.barc.usda.gov
authors.forename: J P
authors.initials: JP
authors.lastname: Dubey
authors.forename: D S
authors.initials: DS
authors.lastname: Lindsay
authors.forename: B M
authors.initials: BM
authors.lastname: Rosenthal
authors.forename: C E
authors.initials: CE
authors.lastname: Kerber
authors.forename: N
authors.initials: N
authors.lastname: Kasai
authors.forename: H F
authors.initials: HF
authors.lastname: Pena
authors.forename: O C
authors.initials: OC
authors.lastname: Kwok
authors.forename: S K
authors.initials: SK
authors.lastname: Shen
authors.forename: S M
authors.initials: SM
authors.lastname: Gennari
mesh_terms: D000818:Animals; D001938:Brazil; D002478:Cells, Cultured; D016054:DNA, Protozoan / Q000235:genetics; D008969:Molecular Sequence Data; D009893:Opossums / Q000469:parasitology*; D016133:Polymerase Chain Reaction; D012522:Sarcocystis / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification
chemical_list: D016054:DNA, Protozoan