|Yai, Lucia E O|
Submitted to: Journal of Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/1/2008
Publication Date: 12/30/2008
Citation: Yai, L., Ragozo, A.M., Aguiar, D.M., Damaceno, J.T., Oliveira, L.N., Dubey, J.P., Gennari, S.M. 2008. Occurrence of Neospora caninum antibodies in capybaras (Hydrochaeris hydrochaeris) from Sao Paulo State, Brazil. Journal of Parasitology. 94:766. Interpretive Summary: Toxoplasma gondii is a single-celled parasite of all warm-blooded hosts worldwide. It causes mental retardation and loss of vision in children, and abortion in livestock. Cats are the main reservoir of T. gondii because they are the only hosts that can excrete the resistant stage (oocyst) of the parasite in the feces. Humans become infected by eating undercooked meat from infected animals and food and water contaminated with oocysts. Scientists at the Beltsville Agricultural Research Center and University of Sao Paulo, Brazil report the isolation of T. gondii from this rodent for the first time. The results will be of interest to biologists, parasitologists, and veterinarians.
Technical Abstract: Capybara (Hydrochaeris hydrochaeris) is a large rodent used for human consumption in certain areas of South America. In the present study, viable Toxoplasma gondii was isolated for the first time from this host. Antibodies to T. gondii were assayed in the sera of 64 capybaras from 6 counties of São Paulo State, Brazil using the modified agglutination test (MAT, =1:25) and the indirect fluorescent antibody test (IFAT, =1:16) and found in 48 (75%) by MAT, and 49 (76.6%) by IFAT. Samples of brain, heart, and tongue of 40 seropositive capybaras were pooled, digested in pepsin, and bioassayed in mice. Toxoplasma gondii was isolated from tissue homogenates of 36 capybaras and the isolates were designated TgCyBr1-36. Most isolates were lethal to mice; 17 of the 36 isolates killed 100% of infected mice, 11 isolates caused mortality in 25-90% of infected mice, and 8 isolates were nonpathogenic to mice. Results indicate that asymptomatic capybaras can harbor mouse-virulent T. gondii, and hence they can serve as a source of infection for humans.