title: Toxoplasma gondii isolates of free-ranging chickens from Rio de Janeiro, Brazil: mouse mortality, genotype, and oocyst shedding by cats.
abstract: Most isolates of Toxoplasma gondii can be grouped into 3 genetic lineages. In the present study, 67 isolates of T. gondii were obtained by bioassay in mice inoculated with brains and hearts of 96 asymptomatic chickens from an area highly endemic to human infection in Rio de Janeiro, Brazil. Of the 48 isolates genotyped using the SAG2 locus, 34 (70%) were of type I and 13 (27%) were of type III. No isolate of type II was recovered. Isolates from 1 chicken contained a type I and type III mixed infection, indicating natural multiparasite infection in the same animal. Cats fed mice infected with 11 type I strains shed 19-535 million oocysts in their feces, indicating that type I isolates can circulate in the environment.
authors.affiliation: Animal Parasitic Diseases Laboratory, Animal and Natural Resources Institute, United States Department of Agriculture, Agricultural Research Service, Building 1001, Beltsville, Maryland 20705, USA. jdubey@anri.barc.usda.gov
authors.forename: J P
authors.initials: JP
authors.lastname: Dubey
authors.forename: D H
authors.initials: DH
authors.lastname: Graham
authors.forename: Daniele Seipel
authors.initials: DS
authors.lastname: da Silva
authors.forename: T
authors.initials: T
authors.lastname: Lehmann
authors.forename: Lilian M G
authors.initials: LM
authors.lastname: Bahia-Oliveira
mesh_terms: D000818:Animals; D000953:Antigens, Protozoan / Q000235:genetics; D001681:Biological Assay / Q000662:veterinary; D001921:Brain / Q000469:parasitology; D001938:Brazil; D002371:Cat Diseases / Q000469:parasitology*; D002415:Cats; D002645:Chickens / Q000469:parasitology*; D016054:DNA, Protozoan / Q000032:analysis / Q000302:isolation & purification; D005243:Feces / Q000469:parasitology; D005260:Female; D005838:Genotype; D006321:Heart / Q000469:parasitology; D008168:Lung / Q000469:parasitology; D008198:Lymph Nodes / Q000469:parasitology; D051379:Mice; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012150:Polymorphism, Restriction Fragment Length; D011201:Poultry Diseases / Q000469:parasitology*; D015800:Protozoan Proteins / Q000235:genetics; D014122:Toxoplasma / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D014124:Toxoplasmosis, Animal / Q000469:parasitology*
chemical_list: D000953:Antigens, Protozoan; D016054:DNA, Protozoan; D015800:Protozoan Proteins; C067547:surface antigen P22, Toxoplasma