Mutation on Theileria species in cattle in Fallujah city, west region of Iraq.

Background: Theileriosis infection is a tick-borne disease that leads to global animal morbidity, mortality, and economic losses.

Aim: This study aimed to examine Theileriosis infection by traditional and molecular methods.

Methods: A total of 100 blood samples of local breed cows were examined by Giemsa smearing under a microscope, amplified-PCR in region 18SrRNA PCR at 600bp, and DNA sequencing analysis of the genetic relationships.

Results: The clinical signs showed that an elevated fever (40.3°C-41.5°C), an asymmetrical extension of superficially prescapular lymph nodes, lacrimation, icteric mucus membranes eyes, ecchymotic hemorrhages on the sclera, dullness, lethargy, salivation, and ticks presence. Giemsa-stained blood smear and conventional PCR were revealed 24% and 73% for infection respectively. The phylogenetic tree was constructed with DNA sequencing analysis of accession number: OQ779946.1, OQ779947.1, OQ779949.1, OQ779952.1, OQ779953.1 and OQ779953.1, belonging to Theileria annulata; acc. nos.: OQ779950.1, OQ779951.1 belong to Theileria parva; acc. nos.: OQ779948.1, OQ779960.1 belongs to Theileria species; acc. no.: OQ779955.1, OQ779957.1, OQ779958.1 belong to T. sergenti; and OQ779956.1, OQ779959.1 belong to Theileria orientalis. Nucleotide substitutions of transversion and transitions occurred in 11 types containing gaps and missing are A>T; A>C; A>G; C>A; C>G; C>T; G>A; G>C; G>T; T>A; T>C for 254 positions in the final dataset.

Conclusion: This study showed theileriosis infection is highly endemic and represents the first investigation into the use of molecular phylogeny to classify Theileria in Fallujah city, West Region of Iraq.