Submitted to: International Journal for Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 22, 1999
Publication Date: N/A
Interpretive Summary: Neospora caninum is a single-celled parasite. It causes abortion in livestock and paralysis and death in companion animals. Neosporosis is a major cause of abortion in dairy cattle in the United States but little is known of its prevalence in central and South America. Scientists at the Beltsville Agricultural Research Center and the Veterinary School, La Plata, Argentina report high prevalence of N. caninum infection in cattle in Argentina. They found N. caninum antibodies in 64.5% of cows that aborted. These results will be of interest to veterinarians and parasitologists.
Antibodies to Neospora caninum were measured in bovine foetuses, dairy cows and beef cows in Argentina using the indirect fluorescent antibody test (IFAT) and the N. caninum agglutination test (NAT). Serum antibodies (IFAT titre ò1:80) were found in 20 of 82 (24.4%) dairy cow foetuses and 1 of 22 (4.5%) beef cow foetuses. Microscopic lesions suggestive of neosporosis were seen in brains of 7 of 8 foetuses with IFAT titres of ò1:80. Antibodies (IFAT) were found in 122 of 189 (64.5%) dairy cows that aborted. Serum antibody titres (IFAT) of 189 dairy cows that aborted were : <1:25 (67 cows), 1:25 (4 cows), 1:50 (16 cows), 1:200 (7 cows), 1:>800 (95 cows). Of the 87 sera with IFAT titres of <1:50, 56 were had no antibodies in 1:40 dilution and 31 had titres of 1:40 in the NAT. Thus, at least 56 dairy cows sera were seranegative both in the NAT and the IFAT. These results suggest that transplacental transmission of N. caninum in dairy cows in Argentina is frequent.