Characterization of Toxoplasma gondii isolates in free-range chickens from Amazon, Brazil.
The prevalence of Toxoplasma gondii in free-ranging chickens is a good indicator of the prevalence of T. gondii oocysts in the soil because chickens feed from the ground. The prevalence of T. gondii in 50 free-range chickens (Gallus domesticus) from Amazon, Brazil, was determined. Antibodies to T. gondii were assayed by the modified agglutination test (MAT) and found in 33 (66%) chickens with titers of 1:5 in 3, 1:10 in 2, 1:20 in 1, 1:40 in 1, 1:80 in 2, 1:160 in 5, 1:200 in 9, 1:400 in 5, 1:800 in 2, 1:1,600 in 2, and 1:3,200 or higher in 1. Hearts and brains of 33 seropositive chickens were bioassayed individually in mice. Tissues from 17 seronegative chickens were pooled and fed to 2 T. gondii-free cats. Feces of cats were examined for oocysts, but none was found. Toxoplasma gondii was isolated from 24 chickens with MAT titers of 1:5 or higher. Genotyping of these 24 T. gondii isolates by polymorphisms at the SAG2 locus indicated that 14 were type I, and 10 were type III; the absence of type II strains from Brazil was confirmed. Fifty percent of the infected mice died of toxoplasmosis, irrespective of the genotype.
Dubey
J P
JP
United States Department of Agriculture, Agricultural Research Service, Animal and Natural Resources Institute, Animal Parasitic Diseases Laboratory, Building 1001, Beltsville, Maryland 20705-2350, USA. jdubey@anri.barc.usda.gov
Gennari
Solange M
SM
Labruna
Marcelo B
MB
Camargo
Luis M A
LM
Vianna
M C B
MC
Marcet
Paula L
PL
Lehmann
T
T
D000372:Agglutination Tests / Q000662:veterinary; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D001681:Biological Assay / Q000379:methods / Q000662:veterinary; D001921:Brain / Q000469:parasitology; D001938:Brazil; D002415:Cats; D002645:Chickens / Q000469:parasitology*; D005243:Feces / Q000469:parasitology; D005838:Genotype; D006321:Heart / Q000469:parasitology; D051379:Mice; D033661:Oocysts / Q000302:isolation & purification; D011201:Poultry Diseases / Q000469:parasitology*; D014122:Toxoplasma / Q000276:immunology / Q000302:isolation & purification* / Q000472:pathogenicity; D014124:Toxoplasmosis, Animal / Q000469:parasitology*
D000913:Antibodies, Protozoan