Modelling population dynamics and response to management options in the poultry red mite Dermanyssus gallinae (Acari: Dermanyssidae)
The poultry red mite Dermanyssus gallinae is a major pest and widespread ectoparasite oflaying hens and other domestic and wild birds. Under optimal conditions, D. gallinae cancomplete its lifecycle in less than 10 days, leading to rapid proliferation of populationsin poultry systems. This paper focuses on developing a theoretical model framework todescribe the population dynamics of D. gallinae. This model is then used to test the efficacyand residual effect of different control options for managing D. gallinae. As well as allowingcomparison between treatment options, the model also allows comparison of treatmentefficacies to different D. gallinae life stages. Three different means for controlling D. gallinaepopulations were subjected to the model using computer simulations: mechanical cleaning(killing once at a given time all accessible population stages), sanitary clearance (starvingthe mite population for a given duration, e.g. between flocks) and acaricide treatment(killing a proportion of nymphs and adults during the persistence of the treatment). Simulationsshowed that mechanical cleaning and sanitary clearance alone could not eradicate themodel D. gallinae population, although these methods did delay population establishment.In contrast, the complete eradication of the model D. gallinae population was achieved byseveral successive acaricide treatments in close succession, even when a relatively lowtreatment level was used.