Molecular characterization, phylogenetic analysis and histopathological changes of Eimeria species infecting domestic pigeons (Columba livia domestica) in Giza governorate, Egypt.

The study was aimed to perform molecular identification of Eimeria spp. infecting domestic pigeons in Giza governorate, Egypt. Also, to study its life cycle in experimentally infected squabs. Molecular identification revealed five species of Eimeria (E. labbeana, E.columbarum, E.columbae, E.columbinae and E. chalcoptereae). Molecular characterization using two primers, the PCR products of Eimeria spp. revealed that the amplified products of the 18S rRNA region had ∼400 bp and 500 bp. Sequencing and phylogenetic analysis of the PCR results indicated that the species under investigation were E. labbeana, E.columbarum, E.columbae, E.columbinae and E. chalcoptereae under accession numbers OR420916, OR554388, OR562036, OR420908 and OR553660, respectively. Experimental infection of squabs with mixed Eimeria spp. revealed that trophozoites, schizonts, macro, microgametocytes and immature oocysts appeared at 12-36 h, 3-4 days, 4-5 days and 6 days post infection (PI), respectively. Histopathological changes in different intestinal parts showed sloughed epithelium, shortened villi and leukocytic cells infiltration. This study is considered as the first molecular characterization and phylogenetic analysis of Eimeria spp. infecting domestic pigeons in Egypt.