Submitted to: Journal of Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/2/2003
Publication Date: 2/2/2004
Citation: Dubey, J.P., Morales, E.S., Lehmann, T. 2004. Isolation and genotyping of toxoplasma gondii from free-ranging chickens from mexico. Journal of Parasitology. 90: 411-413. Interpretive Summary: Infection by the single-celled parasite, Toxoplasma gondii, is common in man and animals. Humans become infected by eating undercooked infected meat or ingesting the resistant stage of Toxoplasma (oocysts) in the environment. Infections in free range-range chickens is indicative of Toxoplasma infection in the environment because chickens feed from the ground. Scientists at the Beltsville Agricultural Research Center and Centers for Disease Control, Atlanta, Georgia, report isolation and molecular characterization of toxoplasma gondii strains from free-range chickens from Mexico for the first time. These results will be of interest to public health workers, parasitologists and veterinarians.
Technical Abstract: : The prevalence of Toxoplasma gondii in free-ranging chickens is a good indicator of the presence of T. gondii oocysts in the environment because chickens feed from the soil. In the present study, prevalence of T. gondii in 208 free-range chickens (Gallus domesticus) from Mexico was investigated. Blood, heart, and brain from each animal were obtained to test for T. gondii infection. Antibodies to T. gondii, assayed with the modified agglutination test (MAT 1:10 or higher), were found in 13 (6.2%) chickens. Hearts and brains of 13 seropositive chickens were bioassayed in mice and T.gondii was isolated from 6 chickens. All 6 isolates were avirulent for mice. Genotyping of chicken isolates of T. gondii using the SAG2 locus indicated that 5 were type III and 1 was type I. This is the first report of isolation of T. gondii from chickens from Mexico.