Ultrastructural and molecular identification of Sarcocystis tenella (Protozoa, Apicomplexa) in naturally infected Korean native goats

Sheep is the intermediate host of the protozoan parasite Sarcocystis tenella, while the dog is its definitive host. This study was conducted to determine the prevalence of natural infection with S. tenella in slaughtered Korean native goat, Capra hircus coreanae, in the Republic of Korea. H-E stained heart tissues were investigated for the presence of sarcocysts. Of the 103 goats, three (2.91%) were diagnosed as positive for S. tenella by light, electron microscopic and molecular examination. The histopathological study showed a low frequency of microscopic Sarcocystis infection in slaughtered goats. In transmission electron microscopy, the sarcocysts were confirmed as S. tenella. Further DNA sequencing and phylogenic analysis support our identification of S. tenella with a 18S rRNA sequence identity of 100% between the experimental sequence and S. tenella. To our knowledge, this is the first record of S. tenella in Korean native goats from Korea. We thus report that the domestic goat is another intermediate host for S. tenella.