Ultrastructure of sarcocystis grueneri-mke sarcocysts from cardiac muscle of red deer (cervus elaphus) in Korea

Sarcocystis grueneri-like sarcocysts were found from the cardiac muscles of a rearing red deer (Cervus elaphus) carcass in Korea. In the light microscopical examination of sarcocysts, they were oval to spherical cysts and 90-170 x 110-380 (μm in size. However, there was no inflammation and myofiber degeneration. In the transmission electron microscope, these cysts were located within the sarcoplasm of the host cell and filled with merozoites. The sarcocysts were enclosed by a very thin wall (0.45-0.6 (μm thick) that consists of protrusions and ground substance. The primary cyst wall formed numerous strip-like protrusions which were 0.2-0.3 μm wide and up to 4.2 (μm long. The protrusions were running in parallel with the surface of the cyst. A characteristic of the cyst wall was absent of fibrils inside the protrusions. Merozoites in the compartment measured about 15x4 μm. The merozoite consisted of four regions: micronemes and rhoptries, amylopectin granule, nucleus, and amylopectin granules. The number of rhoptry was counted in 7-13.