The Poultry Red Mite, Dermanyssus gallinae, travels far but not frequently, and takes up permanent residence on farms

• Published in: Infection, genetics and evolution Vol. 120; p. 105584
• Main Authors: Boulanger, L., Planchon, C., Taudière, A., McCoy, K.D., Burgess, S.T.G., Nisbet, A.J., Bartley, K., Galliot, P., Creach, P., Sleeckx, N., Roy, Lise
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.06.2024; Elsevier
• Subjects: Agricultural sciences; Animal biology; Animal genetics; Animals; Chickens - parasitology; Farms; Gene Flow; Genetic Variation; Genetics; Haplotypes; Hybridization; Life Sciences; Microbiology and Parasitology; Microsatellite Repeats; Microsatellites; Mite Infestations - parasitology; Mite Infestations - veterinary; Mites - genetics; Mitochondrial haplogroups; Parasitology; Population genetics; Populations and Evolution; Poultry - parasitology; Poultry Diseases - parasitology; Poultry red mite; Poultry transport; Santé publique et épidémiologie; Spread; Veterinary medicine and animal Health; Zootechny; Spread; Microsatellites; Poultry red mite; Hybridization; Population genetics; Poultry transport; Mitochondrial haplogroups
• ISSN: 1567-1348; 1567-7257
• DOI: 10.1016/j.meegid.2024.105584

Management of Dermanyssus gallinae, a cosmopolitan hematophagous mite responsible for damage in layer poultry farming, is hampered by a lack of knowledge of its spatio-temporal population dynamics. Previous studies have shown that the circulation of this pest between farms is of strictly anthropogenic origin, that a mitochondrial haplogroup has been expanding on European farms since the beginning of the 21st century and that its local population growth may be particularly rapid. To refine our understanding of how D. gallinae spreads within and among farms, we characterized the genetic structure of mite populations at different spatial scales and sought to identify the main factors interrupting gene flow between poultry houses and between mitochondrial haplogroups. To this end, we selected and validated the first set of nuclear microsatellite markers for D. gallinae and sequenced a region of the CO1-encoding mitochondrial gene in a subsample of microsatellite-genotyped mites. We also tested certain conditions required for effective contamination of a poultry house through field experimentation, and conducted a survey of practices during poultry transfers. Our results confirm the role of poultry transport in the dissemination of mite populations, but the frequency of effective contamination after the introduction of contaminated material into poultry houses seems lower than expected. The high persistence of mites on farms, even during periods when poultry houses are empty and cleaned, and the very large number of nodes in the logistic network (large number of companies supplying pullets or transporting animals) undoubtedly explain the very high prevalence on farms. Substantial genetic diversity was measured in farm populations, probably as a result of the mite's known haplodiploid mode of sexual reproduction, coupled with the dense logistic network. The possibility of the occasional occurrence of asexual reproduction in this sexually reproducing mite was also revealed in our analyses, which could explain the extreme aggressiveness of its demographic dynamics under certain conditions. •Dermanyssus gallinae colonizes egg-production farms through human activities.•We have combined a population genetic analysis using nuclear microsatellites, a field trial and a survey.•Effective contamination by contaminated material introduced into poultry houses is not systematic.•The high persistence after cleaning and the density of the logistics network largely explain the very high prevalence on farms.•Asexual reproductive events could be mixed in with the known sexual reproduction of this haplo-diploid mite.