Submitted to: Journal of Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 26, 1995
Publication Date: N/A
Interpretive Summary: Neospora caninum is a recently discovered protozoan (single celled) parasite of livestock and companion animals. It causes abortion in livestock. Its life cycle and sources of infection are unknown. Transplacental transmission is the only mode of transmission known. There is no vaccine or other method to control neosporosis abortion in livestock. Scientists at the Beltsville Agricultural Research Center and Auburn University, Alabama report a laboratory mouse model of transplacental Neospora infection. The parasite was transmitted to 86% of pups born to pregnant mice inoculated with N. caninum. This model will help to test vaccines and chemotherapy to prevent Neospora abortion in livestock.
Herein we report a murine model to examine transplacental and/or transmammary transmission of Neospora caninum. Prevalence of transplacental transmission in outbred Swiss-Webster mouse pups was 86%, with 11 of 13 litters containing at least 1 transplacentally infected pup. Fifty four percent of litters born to experimentally infected dams contained 90% or more transplacentally infected pups. Numbers of pups congenitally infected per litter was higher if dams were inoculated during the first half of pregnancy. Transplacental transmission decreased to 25% when a singly infected dam delivered a second litter. Transmammary transmission was observed in 1 of 51 pups suckling dams experimentally infected 5, 10 or 15 days post parturition. No pups were infected when cross-fostered onto chronically infected dams.