D. Otoole et al., OVINE MYELOENCEPHALITIS-LEUKOMYELOMALACIA ASSOCIATED WITH A SARCOCYSTIS-LIKE PROTOZOAN, Journal of veterinary diagnostic investigation, 5(2), 1993, pp. 212-225
Bilateral pelvic limb paresis developed in 7 of 15 10-month-old Bluefa
ce Leicester ram lambs on a mixed enterprise farm in the North of Engl
and. Clinical signs were principally mild to severe paresis of the pel
vic limbs. Two mildly affected lambs recovered. Multifocal spinal cord
white matter edema and necrosis, glial nodules, and mild to moderate
nonsuppurative encephalomyelitis were the principal findings in 3 seve
rely paretic lambs examined histologically. Protozoan bodies (12.7-23.
0 mum) that stained immunocytochemically for Sarcocystis epitopes were
in spinal cord glial cells of 2 of 3 lambs. Protozoa did not react im
munocytochemically with anti-Toxoplasma gondii or Neospora canium anti
sera. Serology indicated there was recent exposure to Sarcocystis spp.
in some surviving lambs. These cases resembled those in previous repo
rts of paresis due to an unidentified Sarcocystis-like protozoan in sh
eep (ovine protozoan myeloencephalitis) in the British Isles, the USA,
France, Australia, and New Zealand.