Experimental transmission of Sarcocystis muriviperae n. sp. to laboratory mice by sporocysts from the Palestinian viper (Vipera palaestinae): a light and electron microscope study.

Sporocysts collected from the feces of a Palestinian viper (Vipera palaestinae) were administered orally to species of various rodent genera such as Mus, Microtus, Mastomys, Meriones and Oryctolagus. Infections developed only in laboratory mice (Mus musculus). This investigation established the life cycle of Sarcocystis muriviperae in the laboratory. S. muriviperae is described as a new species, based on light and electron microscopic observations and repeated transmission studies. Naturally and experimentally infected Palestinian vipers both excreted structurally identical sporocysts measuring 9.6 micron (8.8-10.5 microns) by 12.2 microns (11.7-12.9 microns). Sporulation inside the snakes' intestine is completed between 14 and 19 days post-inoculation (p.i.). Rosette-like schizogonic stages were found in the liver cells of laboratory mice 9-10 days after infection with sporulated sporocysts. Sarcocysts measured up to 1,000 microns in length on day 36 p.i. and were mainly filled with metrocytes. The septated sarcocysts found 136 or 165 days p.i. reached a length of 5-8 mm and a width of 150-400 microns. The primary sarcocyst wall formed cauliflower-like branched protrusions about 3.5 microns in length.