Phylogenetic position of the pigeon mite, Ornithonyssus sylviarum, with amplification of its immunogenetic biomarkers in Egypt.

Ornithonyssus sylviarum (O. sylviarum) is an obligatory, blood-sucking ectoparasite widely distributed among poultry and other mammals, causing significant economic losses. This study represented the first report of molecular genotypic identification of O. sylviarum from pigeons, Columba livia domestica, in Egypt. PCR and sequencing of the 28S rRNA gene were conducted. The resulting mite sequences were subjected to BLAST analysis, revealing 90-100% similarity to O. sylviarum in all tested samples. The sequences were deposited in GenBank under the accession numbers PP049086 and PP033720. A phylogenetic tree was constructed to compare the obtained species with related species worldwide. Additionally, infected pigeons showed increased expression of IL-1, IL-10, IFN-γ, and TGF-β3 genes and elevated serum levels of stress biomarkers. The increased level of these cytokines indicates there was a disturbance in the immune status of the infected host with parasite compared with control healthy ones. This increases the susceptibility to infection with other pathogens.