Sarcocystis infection in the white-tailed deer (Odocoileus virginianus) in Montana: intensity and description of Sarcocystis odoi n sp.

Sarcocystis infection was diagnosed in 27 of 36 (75%) samples of meat from white-tailed deer (Odocoileus virginianus) in Montana. Two structurally distinct thin- and thick-walled sarcocysts were found in the white-tailed deer; the thin-walled sarcocysts were those of S odocoileocanis. A new name, S odoi, was proposed for the thick-walled sarcocysts. Sarcocysts of S odoi were up to 1,050 microns long and 260 microns wide and contained a 6.5- to 12-microns thick wall. The ultrastructure of sarcocysts of S odocoileocanis was compared with that of S odoi. A cat fed meat containing thin- and thick-walled sarcocysts shed oocysts and sporocysts 24 days later. The sporocysts in the cat's feces were 13.3 X 9.6 microns and probably belonged to S odoi.