Submitted to: Journal of Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/5/2008
Publication Date: 6/30/2008
Citation: Dubey, J.P., Stone, D., Kwok, O.C., Sharma, R.N. 2008. Toxoplasma gondii and neospora caninum antibodies in dogs from Grenada, West Indies. Journal of Parasitology. 94:750-751.
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. Toxoplasmosis causes mortality in many species of pets, especially dogs and cats. Scientists at the Beltsville Agricultural Research Center and a University in Grenada report high prevalence of T. gondii in dogs. The results will be of interest to biologists, parasitologists, and veterinarians.
Technical Abstract: Toxoplasma gondii and Neospora caninum are structurally similar parasites with many common hosts. The prevalence of antibodies to T. gondii and N. caninum was determined in sera from dogs in Grenada, West Indies. Using a modified agglutination test, antibodies to T. gondii were found in 52 (48.5%) of the 107 dogs with titers of 1:25 in 17, 1:50 in 19, 1: 100 in 7, 1:1,600 in 5 and 1:3,200 or higher in 4. Seroprevalence increased with age from 2.2% in dogs <6- mo- old to 18.9 % in dogs older than 2 yr, indicating post-natal transmission of T. gondii in this population of canines. There was no correlation between the health of dogs and the seroprevalence or the magnitude of T. gondii titer. Antibodies to N. caninum were determined by the indirect immunofluorescent antibody test (IFAT). Two of the 107 dogs had N. caninum antibodies (IFAT titers 1: 100 and 1:400); these dogs had T. gondii titers of 1:50, and 1:1,600. Results indicate that these 2 structurally similar protozoans are antigenically different.