Poultry Red Mite

Infestation with Dermanyssus gallinae, the poultry red mite, is a major health and welfare issue for laying hens worldwide, causing serious reduction in bird performance, a potentially fatal anaemia, and an increased incidence of aggressive pecking and cannibalism which are important welfare considerations. Although chemical pesticides are available, resistance and chemical residues in poultry products are increasingly important factors driving new control methods.

Together with the Avian Science Research Centre, SAC, a new Defra-funded initiative supported by the British Egg Marketing Board, has been performed by Moredun scientists to investigate vaccination as a novel means of red mite control.  Poultry red mites feed on hen’s blood, and the main objective was to induce anti-mite antibodies in the hens and determine the effect of these antibodies (eg mortality, fecundity or feeding) on the mites following a blood feed.  An in vitro feeding assay to screen for these anti-mite antibodies was developed, and we have been able to show that specific proteins can induce antibodies which can kill ~30% of fed mites in less than 24 hours after just one blood feed (fig 1).

Further work is now required to select the best (most effective) mite antigens for vaccination. Current studies have demonstrated the potential for ingested antibodies to rapidly kill mites, and therefore paves the way for the development of a vaccine to control these red mite infestations which commonly occur in commercial environments.

Fig 1 Effect of specific anti-mite antibodies in the blood feed. Within 24 hours of ingesting these antibodies, more than 20% of them are dead when compared to those fed with normal blood.