Submitted to: Journal of Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/17/2004
Publication Date: 10/10/2005
Citation: Dubey, J.P., Lopez, B., Alvarez, M., Mendoza, C., Lehmann, T. 2005. Isolation, tissue distribution, and molecular characterization of toxoplasma gondii from free-range chickens from guatemala. Journal of Parasitology 91:955-957. 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 Guatemala. 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 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 Guatemala was determined. Antibodies to T. gondii were assayed by the modified agglutination test (MAT). Antibodies were found in 37 (74%) chickens with titers of 1:5 in 11, 1: 10 in 7, 1:20 in 11, 1: 40 in 1, 1: 80 in 1, 1: 160 in 3, 1: 1,280 in 2, and 1: 2,560 in 1. Hearts, pectoral muscles, and brains of 19 chickens with MAT titers of 1:20 or more were bioassayed individually in mice. Tissues from the remaining 31 chickens with titers of 1:10 or lower were pooled and fed to 4 T. gondii-free cats (13 chickens with titers of less than 1:5 to 1 cat, 11 chickens with titers of 1:5 to 2 cats, and 7 chickens with titers of 1:10 to 1 cat). Feces of cats were examined for oocystsor more (from 1 of 11 chickens with a titer of 1:20 and all 7 chickens with a titer of 1:80 or more). It was isolated from the heart, brain and pectoral muscle of 3, heart and pectoral muscle of 1, and from the heart alone of 4. Genotyping of these 8 isolates using the SAG2 locus indicated that 5 were Type III and 3 were Type I. This is the first report of isolation of T. gondii from chickens from Guatemala.