Abstract
<jats:p>Ectoparasitic arthropods inhabiting the skin or feathers of avian hosts utilize them for shelter and sustenance, considerably affecting animal health and flock productivity. This study investigated the prevalence, diversity, and intensity indices of ectoparasites infesting domestic pigeons (Columba livia domestica) in Karbala Province, Iraq. The survey was conducted from January 2025 to June 2025 across five districts representing northern, central, and southern geographical zones. A total of 100 domestic pigeons, comprising 63 males and 37 females, were purchased from local markets and clinically examined. Ectoparasites were collected manually, preserved in 70 % ethyl alcohol, cleared in 10 % potassium hydroxide solution, mounted in Canada balsam, and morphologically identified under a digital stereomicroscope. A total of 481 ectoparasites were collected from the 100 pigeons, revealing an exceptionally high overall prevalence of 99 % and a mean abundance of 4.81 parasites per bird. Seven distinct chewing lice species were identified within the recovered parasitic community, which was significantly dominated by Campanulotes bidentatus (54.89 %), followed by Hohorstiella lata (23.91 %) and Columbicola columbae (17.26 %). The remaining species included Columbicola tschulyschman (0.83 %), Columbicola bidentatus (0.42 %), Myrsidea sp. (2.49 %), and Colpocephalum turbinatum (0.21 %). Statistical analysis via the Chi-square test revealed no significant association between ectoparasite prevalence and host sex (χ² = 1.72; P = 0.19). Multiple-species infestations were highly common, with 63 % of the pigeons harboring more than one ectoparasite species, distributed as single (34 %), double (44 %), and triple (19 %) infections. The calculated mean intensity varied among species, with Hohorstiella lata (8.214) and Campanulotes bidentatus (6.947) displaying the highest values. Clinically, infested pigeons exhibited poor, rough feather conditions and restlessness. These findings demonstrate that domestic pigeons in Karbala serve as major reservoirs for diverse chewing lice, highlighting the potential risks for parasite transmission to other avian hosts, including poultry. Consequently, there is an immediate need to enhance local management practices through regular ectoparasiticide applications, improved loft sanitation, and periodic surveillance to effectively protect avian health.</jats:p>