title: Isolation and RFLP Genotyping of Toxoplasma gondii in Free-Range Chickens (Gallus domesticus) in Grenada, West Indies, Revealed Widespread and Dominance of Clonal Type III Parasites.
abstract: The objectives of the present cross-sectional study were to isolate and genotype Toxoplasma gondii in free-range chickens from Grenada, West Indies. Using the modified agglutination test, antibodies to T. gondii were found in 39 (26.9%) of 145 free-range chickens with titers of 25 in 7 chickens, 50 in 6 chickens, 100 in 2 chickens, and 200 or higher in 24 chickens. The hearts of the 39 seropositive chickens were bioassayed in mice; viable T. gondii was isolated from 20 and further propagated in cell culture. Genotyping of T. gondii DNA extracted from cell-cultured tachyzoites using the 10 PCR-restriction fragment length polymorphism (RFLP) markers SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico revealed 4 genotypes, including ToxoDB PCR-RFLP no. 2 (Type III), no. 7, no. 13, and no. 259 (new). These results indicated that T. gondii population genetics in free-range chickens seems to be moderately diverse with ToxoDB no. 2 (Type III) as the most frequent (15/20 = 75%) compared to other genotypes in Grenada.
authors: Pathobiology Department, School of Veterinary Medicine, St. George's University, Grenada, West Indies.
authors: Alfred
authors: A
authors: Chikweto
authors: Pathobiology Department, School of Veterinary Medicine, St. George's University, Grenada, West Indies.
authors: Ravindra N
authors: RN
authors: Sharma
authors: Pathobiology Department, School of Veterinary Medicine, St. George's University, Grenada, West Indies.
authors: Keshaw P
authors: KP
authors: Tiwari
authors: Pathobiology Department, School of Veterinary Medicine, St. George's University, Grenada, West Indies.
authors: Shiv K
authors: SK
authors: Verma
authors: Pathobiology Department, School of Veterinary Medicine, St. George's University, Grenada, West Indies.
authors: Rafael
authors: R
authors: Calero-Bernal
authors: Pathobiology Department, School of Veterinary Medicine, St. George's University, Grenada, West Indies.
authors: Tiantian
authors: T
authors: Jiang
authors: Pathobiology Department, School of Veterinary Medicine, St. George's University, Grenada, West Indies.
authors: Chunlei
authors: C
authors: Su
authors: Pathobiology Department, School of Veterinary Medicine, St. George's University, Grenada, West Indies.
authors: Oliver C
authors: OC
authors: Kwok
authors: Pathobiology Department, School of Veterinary Medicine, St. George's University, Grenada, West Indies.
authors: Jitender P
authors: JP
authors: Dubey
mesh_terms: D000372:Agglutination Tests / Q000662:veterinary; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D001681:Biological Assay / Q000662:veterinary; D002645:Chickens / Q000469:parasitology*; D003430:Cross-Sectional Studies; D005838:Genotype; D060005:Genotyping Techniques / Q000662:veterinary*; D019425:Grenada / Q000453:epidemiology; D006321:Heart / Q000469:parasitology; D051379:Mice; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D011201:Poultry Diseases / Q000453:epidemiology / Q000469:parasitology*; D016036:Seroepidemiologic Studies; D014122:Toxoplasma / Q000145:classification / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D014124:Toxoplasmosis, Animal / Q000453:epidemiology / Q000469:parasitology*
chemical_list: D000913:Antibodies, Protozoan