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

Abstract

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 aimed to identify Sarcocystis species in camels by molecular assay with confirmation of local isolates by phylogenetic analysis.
Methods: A total of 200 slaughtered camels (Camelus dromedarius) that were slaughtered in Al-Najaf province (Iraq)
abattoirs from 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, got 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, an increase in Sarcocystis infection was seen in the esophagus compared to the diaphragm, skeletal muscle, and heart; older (>4 years) than younger (≤4 years) camels, and in females more than males.
Conclusion: To the best of our knowledge, this represents the first molecular study in Iraq that 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