Diversity and ecology of Sarcocystis in Lithuanian game fauna

Abstract

Up till now ecology and biodiversity of Sarcocystis species in game fauna in Lithuania has been investigated using traditional morphological methods. In the period of 2005-2011, muscle samples of 384 birds and 177 mammals were examined for Sarcocystis sarcocysts. Cysts of Sarcocystis spp. were investigated using light microscopy, transmission electron microscopy and DNA analysis (18S rDNA, 28S rDNA, ITS–1 region). Statistically significant higher Sarcocystis infection prevalence and intensity rates (p< 0.05) were determined in mammals as compared to the birds. Macrocysts were detected only in the mallard, they were identified as S. rileyi and this is the first evidence of S. rileyi infection in Europe. Based on results of cyst wall ultrastructure and DNA analysis four new bird Sarcocystis species were described: S. albifronsi, S. wobeseri, S. anasi, S. cornixi. Eight Sarcocystis species were identified in the examined mammals using morphological and DNA analysis: S. miescheriana from wild boar; S. gracilis, S. capreolicanis, S. oviformis, S. silva and S. hofmanni-like from roe deer; S. hjorti, S. hofmanni-like and Sarcocystis sp. ex Cervus elaphus from red deer; S. hjorti from moose. S. columbae, S. oviformis, S. hjorti and S. silva were found in Lithuania for the first time. Using molecular investigation it was proved that some analyzed Sarcocystis species (S. wobeseri, S. hjorti, S. silva and S. hofmanni-like) are not rigidly specific to the intermediate host. Sarcocystis species in the phylogenetic trees of 18S rDNA and 28S rDNA were grouped according to the similarity of the morphological characteristics and relatedness of intermediate and definitive hosts