The poultry red mite Dermanyssus gallinae is best known as a threat to the laying-hen industry; adversely affecting production and hen health and welfare throughout the globe, both directly and through its role as a disease vector. Nevertheless, D. gallinae is being increasingly implemented in dermatological complaints in non-avian hosts, suggesting that its significance may extend beyond poultry. The main objective of the current work was to review the potential of D. gallinae as a wider veterinary and medical threat. Results demonstrated that, as an avian mite, D. gallinae is unsurprisingly an occasional pest of pet birds. However, research also supports that these mites will feed from a range of other animals including: cats, dogs, rodents, rabbits, horses and man. We conclude that although reported cases of D. gallinae infesting mammals are relatively rare, when coupled with the reported genetic plasticity of this species and evidence of permanent infestations on non-avian hosts, potential for host-expansion may exist. The impact of, and mechanisms and risk factors for such expansion are discussed, and suggestions for further work made. Given the potential severity of any level of host-expansion in D. gallinae, we conclude that further research should be urgently conducted to confirm the full extent of the threat posed by D. gallinae to (non-avian) veterinary and medical sectors.

Insects will likely play an important role as protein sources for livestock in the future. Many insect species are able to convert materials not suitable for human nutrition -or even waste -into valuable protein with a favourable amino acid composition for poultry and other livestock. A feeding trial with partly de-fatted meal of dried Hermetia illucens larvae (Hermetia meal) reared on vegetarian by-products of the pasta and convenience food industry was carried out in small groups of Lohmann Selected Leghorn laying hens (four rounds, 10 hens/round). Experimental diets H12 and H24 contained 12 and 24 g/100 g Hermetia meal replacing 50 or 100% of soybean cake used in the control feed, respectively. After three weeks of feeding experimental diets, there were no significant differences between feeding groups with regard to performance (egg production, feed intake). There was a tendency (P=0.06) for lower albumen weight in the H24 group; yolk and shell weights did not differ. No mortality and no sign of health disorders occurred. Plumage as well as wound scores remained stable during the feeding period and did not differ between treatments. Dry matter of faeces increased with increasing proportions of Hermetia meal in the diet, with a significant difference between H24 and the control (P=0.03). An increase of black faecal pads was observed in the H12 and H24 groups. Overall, these results suggest Hermetia meal can be a valuable component of layer diets. However, insect meal production still has to become economically more viable through upscaling production and, especially, legislative issues have to be solved.

We investigated direct anthelmintic effects associated with the feeding of fresh tanniferous forages against established populations of Haemonchus contortus and Cooperia curticei in lambs. Twenty-four parasite naive lambs were inoculated with a single dose of infective larvae of these two parasites 27 days prior to the start of the feeding experiment. Lambs were individually fed with either chicory (Cichorium intybus), birdsfoot trefoil (Lotus corniculatus), sainfoin (Onobrychis viciifolia) or a ryegrass / lucerne mixture (control) for 17 days. Animals where then united to one flock and subjected to control feeding for another 11 days to test the sustainability of potentially lowered egg excretion generated by tanniferous forage feeding. When compared to the control, administration of all tanniferous forages was associated with significant reductions of total daily faecal egg output specific to H. contortus (chicory: 89 %; birdsfoot trefoil: 63 %; sainfoin: 63 %; all tests P < 0.05) and a tendency of reduced H. contortus worm burden (chicory: 15 %; birdsfoot trefoil: 49 % and sainfoin: 35 % reduction). Irrespective of the condensed tannin (CT) containing fodder, no anthelmintic effects were found against C. curticei. Cessation of CT-feeding followed by non-CT control feeding did not result in a re-emergence of faecal egg counts based on faecal dry matter (FECDM) in any group, suggesting that egg output reductions are sustainable. The moderate to high concentrations of CTs in birdsfoot trefoil (15.2 g CTs kg -1 dry matter (DM)) and sainfoin (26.1 g CTs kg -1 DM) were compatible with the hypothesis that the antiparasitic effect of these forages is caused by their content of CTs. For chicory (3 g CTs kg -1 DM), however, other secondary metabolites need to be considered. Overall, birdsfoot trefoil and in particular sainfoin seem promising candidates in contributing to an integrated control strategy against H. contortus not only by mitigating parasite related health disturbances of the host but also by a sustained reduction of pasture contamination.

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This paper reports the results of a seminar on poultry red mite (PRM), Dermanyssus gallinae. Eighteen researchers from eight European countries discussed life cycle issues of the mite, effects of mites on hens and egg production, and monitoring and control methods for PRM in poultry facilities. It was determined that PRM probably causes more damage than envisaged, with the cost in The Netherlands alone reaching 11 million euro per annum. However a great deal is still unknown about PRM (e.g. reproduction, survival methods, etc.) and that PRM monitoring is an important instrument in recognising and admitting the problem and in taking timely measures. Currently, the most promising control method combines heating the hen house in combination with chemical treatments. Future areas of development which show promise include the use of entomopathogenic fungi, vaccination and predatory mites. The final aim is to solve the problem of D. gallinae in housing systems for laying hens.