RESUMO
Sarcocystosis is caused by species of Sarcocystis, an intracellular protozoan parasite in the phylum Apicomplexa. The intermediate hosts are the herbivores eating infected food or water containing sporocysts excreted by the carnivorous final host, and that results in tissue cysts in corpses. The present study was carried out to identify Sarcosystis species of sheep using PCR-RFLP. In the present study 60 specimens from the diaphragm, heart and esophagus muscles of sheep slaughtered in Qazvin Ziaran slaughterhouse were collected. 40 specimens contained macroscopic Sarcocystis cysts and the next 20 contained microscopic Sarcocystis cysts. They were examined by Dob Smear and digestion method. DNA extraction was carried out by a kit. PCR conditions were optimized for 18S rRNA amplification. Meanwhile, a comparative study was done to investigate the specific primers of the Toxoplasma and Neospora along with the Sarcocystis cases. According to the position of restriction sites, restricted enzymes were selected. Results indicated that the primers were completely unique and specific for detecting Sarcocystis. PCR-RFLP analysis showed that macroscopic cysts and microscopic cysts belonged to Sarcocystis gigantea and Sarcocystis arieticanis, respectively. Sarcocystis species of sheep can be recognized through PCR-RFLP technique using the designed specific primers. By this technique applying TaqI enzyme from microscopic cysts as well as TaqI and HincII enzymes for macroscopic cysts were found more efficient than the others