Submitted to: Veterinary Parasitology Publication Type: Peer
Reviewed Journal Publication Acceptance Date: October 1, 2000
Publication Date: N/A Interpretive Summary: Sarcocystis neurona
is a single-celled parasite of companion animals. It causes a
fatal neurologic syndrome in horses in the U.S., called eqine
protozoal myeloencephalitis (EPM). Its full life cycle is not
known. Opossums are its reservoir (definitive) host and horses
are considered aberrant hosts. Scientists at the Beltsville
Agricultural Research Center and the Montana State University
describe the ultrastructure of Sarcocysti neurona stages
(schizonts) found in tissues of horses. These results will be of
interest to biologists and parasitologists. The ultrastructure
events associated with nuclear division were studied in
schizonts of Sarcocystis neurona. Merozoites developed by type 2
endopolygeny in which numerous merozoites began development
internally and later budded at the schizont surface. The nuclear
envelope remained intact during all