Abstract The poultry red mite ( Dermanyssus gallinae ) is a hematophagous ectoparasite of major economic and veterinary importance worldwide. Its occurrence in both domestic and wild avian hosts raises important questions regarding genetic diversity, host association, and dispersal dynamics. In this study, mites were collected from two commercial poultry farms and from a single wild barn owl ( Tyto alba ) in northern Iran. Specimens were identified morphologically and molecularly using mitochondrial cytochrome oxidase subunit I (COX1) and nuclear internal transcribed spacer 2 (ITS2) gene markers. PCR amplification of both COX1 and ITS2 was successful in poultry-derived samples, whereas only ITS2 was amplified from owl-derived mites. Sequence analysis showed that poultry-derived isolates shared up to 99% identity with previously reported D. gallinae sequences, indicating close genetic similarity. In contrast, the ITS2 sequence obtained from owl-derived mites exhibited approximately 90% similarity with reference sequences, suggesting notable genetic divergence. Phylogenetic analyses placed poultry-derived mites within the main D. gallinae clade, while the owl-derived ITS2 sequence formed a separate branch. However, given the limited wild-bird sampling, this divergence should be interpreted as a preliminary observation rather than definitive evidence of host-specific or novel lineages. Overall, this study provides exploratory molecular data on D. gallinae from poultry and a wild bird in northern Iran and highlights the importance of incorporating wildlife hosts into future large-scale molecular epidemiological investigations of poultry ectoparasites.
Tabaripour et al. (Fri,) studied this question.