Equine neosporosis is caused by the protozoans Neospora caninum and N. hughesi. Its clinical signs include hindlimb paralysis, incoordination, ataxia, and abortion. Serum and cerebrospinal fluid (CSF) samples were collected from 38 equines with history of ataxia for indirect fluorescent antibody test (IFAT) in order to detect antibodies to N. caninum. Of the tested serum samples 15/26 (57.6%) were positive, whereas all CFS samples were negative. These seronegative CFS samples suggest that N. caninum has no relation to the manifestation of the neurological clinical signs of ataxia.