Abstract
Objective—To determine whether antibodies against Sarcocystis neurona could be detected in CSF from clinically normal neonatal (2 to 7 days old) and young (2 to 3 months old) foals.
Design—Prospective study.
Animals—15 clinically normal neonatal Thoroughbred foals.
Procedure—Serum and CSF samples were obtained from foals at 2 to 7 days of age and tested for antibodies against S neurona by means of western blotting. Serum samples from the mares were also tested for antibodies against S neurona. Additional CSF and blood samples were obtained from 5 foals between 13 and 41 days after birth and between 62 and 90 days after birth.
Results—Antibodies against S neurona were detected in serum from 13 mares and their foals; antibodies against S neurona were detected in CSF from 12 of these 13 foals. Degree of immunoreactivity in serum and CSF decreased over time, and antibodies against S neurona were no longer detected in CSF from 2 foals 83 and 84 days after birth. However, antibodies could still be detected in CSF from the other 3 foals between 62 and 90 days after birth.
Conclusions and Clinical Relevance—Results indicate that antibodies against S neurona can be detected in CSF from clinically normal neonatal (2 to 7 days old) foals born to seropositive mares. This suggests that western blotting of CSF cannot be reliably used to diagnose equine protozoal myeloencephalitis in foals < 3 months of age born to seropositive mares. (J Am Vet Med Assoc 2002;220:208–211)
