Production losses in laying hens during infestation with the poultry red mite Dermanyssus gallinae

Abstract

A research centre with 30,568 laying hens, kept in enriched cages and in aviaries, had become naturally infested with poultry red mites (PRM) in 32 of its 48 bird units. Therefore, at the age of 52 weeks all hens were treated with fluralaner through the drinking water. After this treatment, PRM were no longer observed. As all birds were of the same age, and since production figures were measured daily in all 48 units, this offered a unique opportunity to examine how PRM had affected performance. Statistical analyses were done to compare the evolution of production data from the pre-treatment to the post-treatment period in units that were visually free of PRM or infested with PRM to different levels. Production standards provided by the breeding organizations were used as a reference. The results demonstrated significant posttreatment increases of laying percentage, egg weight, egg mass, percentage first choice eggs, feed intake and body weight in heavily infested hens of one or both housing systems, as compared to the non-infested controls. These data confirm that PRM infestations can impact the main performance traits related to profitability of laying hen farms as well as the hens' general condition. ARTICLE HISTORY

Possibilities for IPM Strategies in European Laying Hen Farms for Improved Control of the Poultry Red Mite (Dermanyssus gallinae): Details and State of Affairs

“…Much research has been done, and is still being done on the use of alternative non-chemical treatments, like plant-based products, natural predators and vaccines (see below Non-chemical Treatment Methods). However, none of these seem to be efficient enough to serve as a standalone treatment against D. gallinae (16). The only sustainable solution to control D. gallinae infestation is to use multi-tactic Integrated Pest Management programmes, as already suggested by several authors (5,(20)(21)(22)(23).…”

“…The difficulty in determining thresholds lies partly in the complexity of determining the actual population size and the multitude of influencing variables (see above). In addition, although production losses due to D. gallinae infestations have been evidenced (16), the exact relationships between infestations and bird health/economic impact are insufficiently known. Also here, the many influencing factors hamper the determination of economic thresholds.…”

“…In addition, the percentage of second quality eggs increases due to a.o. blood spots (15,16). Based on literature and field experience, Van Emous (2005) estimated the economic damage of D. gallinae infestations.…”

Challenges for the Control of Poultry Red Mite (Dermanyssus gallinae)

“…Moderate and low infestations do not seem to have an effect on the production parameters independently of the layer hen productive system [39]. Instead, severe infestations are associated with important production losses albeit variations between housing systems [21].…”

“…Instead, severe infestations are associated with important production losses albeit variations between housing systems [21]. Therefore, PRM has been demonstrated to negatively affect the proportion of laying hens, egg weight and the amount of first-choice eggs in enriched cages facilities while detrimental effects have been observed on egg mass, first-choice eggs and bodyweight of hens housed in aviary systems [39]. The impact on egg production can cause reductions of up to 20% [8].…”