The genus Sarcocystis is an abundant group of Apicomplexa parasites found in mammals, birds, and reptiles. These parasites are characterised by the formation of sarcocysts in the muscles of intermediate hosts and the development of sporocysts in the intestines of definitive hosts. The identification of Sarcocystis spp. is usually carried out in carcasses of animals, while there is a lack of studies on the detection of Sarcocystis species in blood samples. In the current study, blood samples of 214 yellow-necked mice (Apodemus flavicollis) and 143 bank voles (Clethrionomys glareolus) from Lithuania were examined for Sarcocystis. The molecular identification of Sarcocystis was carried out using nested PCR of cox1 and 28S rRNA and subsequent sequencing. Sarcocystis spp. were statistically (p < 0.01) more frequently detected in the bank vole (6.3%) than in yellow-necked mice (0.9%). The analysed parasites were observed in four different habitats, such as mature deciduous forest, bog, natural meadow, and arable land. Three species, Sarcocystis funereus, Sarcocystis myodes, and Sarcocystis cf. glareoli were confirmed in the bank vole, whereas only Sarcocystis myodes were found in yellow-necked mice. The obtained results are important in the development of molecular identification of Sarcocystis parasites in live animals.
Keywords: 28S rRNA; Sarcocystis; blood; cox1; genetic identification; prevalence; rodents.