Molecular identification and phylogenetic confirmation of Sarcocystis species in slaughtered camels in Al-Najif province, Iraq

Background: Sarcocystis is an intracellular parasite of particular importance as it infects many domestic animals as camels that play the role of intermediate host for the parasite. Aim: This study was aimed to identify Sarcocystis species in camels by molecular assay with confirmation of local isolates by phylogenetic analysis. Methods: Totally, 200 slaughtered camels (Camelus dromedarius) which slaughtered in Al-Najaf province (Iraq) abattoirs during October (2021) to July (2022) were subjected to collect the fresh tissues from four organs (esophagus, diaphragm, skeletal muscle and heart), to be tested later by the conventional polymerase chain reaction (PCR). Then, a total of 20 positive genomic DNA samples were sequenced, named, get specific access numbers (OP785703.1 to OP785722.1), and compared with the NCBI-GenBank isolates. Results: Targeting Cox1 gene, 80% of collected tissues were found positive by the conventional PCR assay. Phylogenetic tree analysis revealed that the local Sarcocystis isolates were identical to Indian S. cameli isolates at 99.70-99.90%. Significantly, increasing in Sarcocystis infection was seen in esophagus compared to diaphragm, skeletal muscle and heart; older (4 years) than younger (4 years) camels, and in females more than males. Conclusion: For our knowledge, this represents the first molecular study in Iraq which identifies Sarcocystis cameli in camels. However, additional epidemiological and molecular studies in camel populations as well as in other domestic and wild animals appeared to be necessary.