Sarcocystis spp. diversity in the roe deer (Capreolus capreolus) from Lithuania and Spain

The roe deer (Capreolus capreolus) has been identified as an intermediate host for six known Sarcocystis species, S. capreolicanis, S. entzerothi, S. gracilis, S. linearis, S. oviformis, and S. silva. In this study, we identified Sarcocystis species in the diaphragm and tongue muscles from the Lithuanian and Spanish roe deer, respectively, on the basis of a microscopic examination and DNA analysis. A total of 43 and 27 sarcocysts were isolated and characterized from the Lithuanian and Spanish roe deer, respectively. Overall six Sarcocystis species were identified in roe deer from Lithuania, and only three of them, S. gracilis, S. linearis, and S. silva were found to have infecting animals from Spain. The current paper represents first molecular results of Sarcocystis species in the Spanish roe deer. Furthermore, transmission electron microscopy examination revealed specific wall structure of sarcocysts studied, S. linearis was characterized by ribbon-like villar protrusions (vp) (type 8a), and S. oviformis was distinguished by elongated vp resembling spades or mushroom-like structures (type 39). Based on 18S rDNA and cox1 sequences, Sarcocystis species from the roe deer showed considerable intraspecific genetic variability. However, similar values of intraspecific genetic variation were estimated at both genes analysed. The highest variability was observed for S. capreolicanis and S. linearis in both genes and for S. silva at cox1. Consequently, the level of genetic variability of Sarcocystis from the roe deer varied depending on species rather than on gene analysed or geographical area.