1 Department of Integrated Pest Management, Faculty of Agricultural Sciences, Aarhus University, Aarhus University2 Danish Pest Infestation Laboratory, Faculty of Agricultural Sciences, Aarhus University, Aarhus University3 Department of Agroecology - Entomology and Plant Pathology, Department of Agroecology, Science and Technology, Aarhus University4 Department of Agroecology - Entomology and Plant Pathology, Department of Agroecology, Science and Technology, Aarhus University
The poultry red mite (PRM), Dermanyssus gallinae, is the most important ectoparasite in European egg production. The mites hide in cracks and crevices in the near vicinity of the resting places of the birds, coming out to feed mainly during the night. Under favourable conditions the population can grow rapidly, leading to serious problems. Large mite populations may cause anaemia or even death to the poultry, but also in lower numbers mites may be a nuisance to the birds causing decreased egg production and egg quality. Furthermore, they may have the potential of acting as reservoir/carriers for various micro-organisms e.g. Salmonella. In SAFEHOUSE, an EU-project running from 2006-2009, partners from 11 European countries aim at developing new methods for prevention and control of Salmonella in egg production systems with particular focus on the transition to enriched cages in the EU. Enriched cages contain perches, nest boxes and dust bathing areas. This improves the welfare of the hens but also provides more hiding places for the PRM and may thus lead to increased ectoparasite problems. The approach taken against the PRM is to develop new control methods based on a combination of mite-pathogenic fungi and desiccant dust. The dust is diatomaceous earth (of natural origin), synthetic silica products or combinations of the two. The progress of the work with desiccant dusts will be reported. So far, 7 different products have been tested in the laboratory with regard to their efficacy, speed of action and repellency to the PRM at different level of air humidity. There are important differences between the products on all parameters and the ideal choice will have to take them all into consideration.