In vitro isolation and characterisation of a bovine Neospora species in Japan

Eleven aborted bovine fetuses and five calves suspected as having neosporosis were necropsied and tissues from these animals were inoculated into bovine cardiopulmonary aortic endothelial cells and monkey kidney cells and maintained at 37°C with 5 per cent CO₂. Neospora tachyzoites were observed in one cell 49 days after inoculation. The isolated parasite (JPA1) was morphologically identical to the previously reported bovine Neospora species (BPA1) and confirmed by its strong antigenic reactivity with bovine control antisera to Neospora species and its lack of reactivity with Toxoplasma gondii and Sarcocystis cruzi antisera. This is the first bovine Neospora species isolate in Asia and further studies with this isolate are now expected.