Oocysts/sporocysts of Sarcocystis sp. were found in the intestinal contents of the smooth snake, Coronella austriaca I .aurenti. Common voles Microtus arvalis (Pallas), bank voles Clethrionomys glareolus (Schreber), green lizards Lacerta viridis (Laurcnti), and common wall lizards Podarcis muralis (Laurenti) were experimentally inoculated as potential intermediate hosts. Only common wall lizards were found to be susceptible intermediate hosts. Transparent, macroscopically hardly visible sarcocysts found in tail striated muscles of lizards were 480 (390-640) x 210 (190-230) pm in size 72 days post-infection. Using the light microscopy, the sarcocyst wall was about 1 pm thick with an apparent layer of villi approx. 2 pm thick. Ullraslruclurally, the primary cyst wall was characterised by spine-like villar protrusions up to 2.5 pm in length and 0.5 pm in diameter. Based on sarcocyst morphology and experimental data, the discovered Sarcocystis species is suggested to be conspccific with Sarcocystis lacertae Babudieri, 1932. A redescription of Sarcocystis lacertae is presented in this study.
Four laboratory-hatched European kestrels Falco tinnunculus L. were fed on laboratory mice and common voles Microtus arvalis Pallas previously inoculated with different doses of sporulated oocysts of Caryospora kutzeri Böer, 1982. Two kestrels that were fed infected mice shed C. kutzeri oocysts 6 days after ingesting murine tissues. To compare direct and indirect transmissions, two of the kestrels were subsequently directly inoculated with 105 sporulated C. kutzeri oocysts and became patent on days 8 and 9 and shed caryosporan oocysts up to day 25 post inoculation. Additionally, four mice were inoculated with 106 oocysts in order to examine mouse tissues for the presence of developmental stages of C. kutzeri. No coccidian stages were found in the tissues of inoculated mice. The experiment showed that developmental stages of C. kutzeri are able to survive in mouse tissues and cause infection of suitable host after their ingestion.
During a survey of the coccidian parasites of reptiles, caryosporan oocysts were found in the faeces of wild and captive European viperid snakes Vipera berus (L.) and V. ammodytes (L.). Thirty two of 37 examined V. herus (86%) and 9 of 17 examined V. ammodytes (53%) specimens were found to be passing caryosporan oocysts. Morphological characters of all caryosporan isolates were identical and fitted well with the description of Caryospora simplex Léger, 1904. Experimental inoculation of severe combined immunodeficient (SC1D) mice with seven isolates of C. simplex from V. berus or V. ammodytes confirmed the heteroxenous life cycle pattern, for the first time for isolates of evidently European origin. Caryosporan developmental stages were observed in the connective tissues of the nose, cheeks, ear and scrotum in all inoculated SCID mice. V. berus and V. ammodytes represent new hosts for C. simplex. The present paper represents the first widely based report on coccidian parasites of the genus Caryospora Léger in European viperids. Our findings indicate a wide distribution of C. simplex throughout the range of distribution of snakes of the genus Vipera.