Gallinae Infestation Research Articles

Administering Fluralaner in Drinking Water for Treatment of Dermanyssus gallinae Infestation in Hy-Line W80 Laying Hens

Background: Poultry red mites, or Dermanyssus gallinae, pose a threat to the welfare and productivity of laying hens. Moreover, the increasing resistance of these mites to conventional miticides highlights the urgent need for alternative treatment options. There are also documented cases of poultry red mite infestations in humans. Objectives: The primary objective of this study was to evaluate the efficacy of fluralaner against Dermanyssus gallinae infestation in hens. Methods: Fluralaner was selected as a novel treatment for poultry red mite due to its effectiveness and safety profile. The presence of live mites in the drinking water tank served as the indicator of infestation. Live mites were counted on nine occasions throughout the study. Fluralaner was administered at three doses of 0.5 mg/kg in drinking water with a seven-day interval between each dose. The efficacy of fluralaner was assessed, with an efficacy percentage exceeding 90% considered indicative of antiparasitic efficacy. Results: The overall efficacy of Fluralaner in the current study exceeded 90% by day 5 and reached 100% by day 17. Conclusions: This study demonstrates that fluralaner is an effective alternative treatment, achieving efficacy rates exceeding 90% against poultry red mite infestation in laying hens.

One health approach to study human health risks associated with Dermanyssus gallinae mites

Despite the significant health risks associated with Dermanyssus gallinae infestations in humans, they are often overlooked. This study investigated a household case of D. gallinae infestation and explored the resulting clinical manifestations and risk of infection in family members. Microfluidic PCR was employed for high-throughput screening of pathogens in collected mites and blood samples from both chickens and family members. Morphological and molecular examinations confirmed the identity of the mites as D. gallinae sensu stricto (s.s.), with evidence indicating recent blood feeding. Results indicated that the mites exclusively harbored various pathogens, including Bartonella spp., Ehrlichia spp., Apicomplexa, and Theileria spp. Blood samples from family members and poultry tested negative for these pathogens, suggesting a potential reservoir role for D. gallinae. The study further identified haplotypes of D. gallinae, classifying them into D. gallinae s.s., cosmopolitan haplogroup A. Serological analysis revealed elevated IgE seroreactivity against mite proteins in the family member with bite lesions. Antibodies against Bartonella spp. were detected in this individual, indicating exposure to the pathogen. In summary, this study sheds light on the clinical manifestations, pathogen detection, and genetic characterization of D. gallinae infestations, underscoring the necessity of adopting comprehensive approaches to manage such infestations effectively.

Spatial Distribution of Dermanyssus gallinae Infestations in Greece and Their Association with Ambient Temperature, Humidity, and Altitude.

Dermanyssus gallinae, the poultry red mite (PRM), is the most prevalent and harmful ectoparasite of laying hens globally. Although prevalence and risk factor studies can help veterinarians make decisions regarding farm treatments, relevant data are scarce. The present study investigated the prevalence and infestation severity of PRM in poultry farms across Greece and examined potential risk factors. AviVet traps were used to sample 84 farms (51 backyard, 33 industrial) over three years. Farm altitude, temperature, humidity, region, and production systems were assessed as potential risk factors with chi-square tests, initially for all the studied farms and then exclusively for backyard farms. The overall prevalence was 75.0% and was higher in backyard farms (80.4%) compared with industrial ones (66.7%), varying regionally from 66.7 to 90.9%. Altitude and temperature were not significant risk factors, but farms with humidity <60% had a lower infestation risk. Infestation severity did not significantly differ by risk factors. The poultry red mite is highly prevalent across Greek poultry production systems and regions. In the future, global warming, reduced acaricide options, and a ban on cage systems will all threaten a wider spatio-temporal distribution of the PRM, justifying the urgent need for effective monitoring and control methods to protect hen production and welfare and workers' health.

Investigation of ectoparasites in budgerigar and canaries in Burdur city of Turkey

Ectoparasite infestations are of the most important and neglected diseases of birds. Ectoparasites cause sirious harmful effects such as; irritation, feathers and skin damage, restlessness, anemia, weight loss, transmission of other pathogens, reducing overall fitness and decreasing long term survival depending on the intensity of the infestation. The main objective of this study was to investigate the ectoparasites of budgerigars and canaries in Burdur city of Turkey. The material of the study was consisted of randomly selected 555 budgies in 192 cages and 121 canaries in 49 cages belongs to 12 different breeders in center district of Burdur city, Turkey. The feathers of head, neck, abdomen, legs, tail, beak, under the wings, around the cloaca and feet of all birds, in addition cages and cage equipments have been examined in terms of ectoparasites. As a result; no ectoparasite species were found on/between feathers and other body parts of overall 676 cage birds, however, a large number of Dermanyssus gallinae were found in cages and cage equipments. Dermanyssus gallinae have been detected in rates of 28.65% and 28.57% in budgerigar and canary cages, respectively. The present study is the first investigation study of ectoparasites of budgerigar and canaries in Turkey and rarely in the world. In addition, within this study D. gallinae infestation is being reported for the first time from budgerigar and canaries from Turkey.

Successful long-term control of poultry red mite (Dermanyssus gallinae) infestations in floor-kept laying hens via integrated pest management—a case report

This case report describes the successful control of poultry red mite [PRM] (Dermanyssus gallinae) infestations in an experimental laying hen house via a combined use of cleaning and disinfection measure, the preventive application of a synthetic silica-based acaricide and frequent mite monitoring. The high number of PRM in the laying hen house was reduced by 99.8% by treatment with fluralaner (Exzolt®, MSD Animal Health Unterschleißheim, Germany; 0.5 mg/kg body weight via drinking water twice, 7 days apart). After the laying hens were removed, the hen house was dry-cleaned, wet-cleaned and disinfected. After drying, synthetic amorphous silica (Fossil Shield® instant white, Bein GmbH, Eiterfeld, Germany) was applied as a preventive measure before the hen house was restocked with pullets for two housing periods of 58 and 52 weeks. Over these periods (i.e. more than 2 years), no PRM was detected during mite monitoring at two-week intervals via tube traps and visual monitoring. This result therefore suggests that the combined use of appropriate chemical and physical prevention measures within an integrated pest management regime can be successfully used for the long-term control of PRM. This could reduce the use of acaricidal drugs, thereby helping maintain their efficacy.

Studies on the Control of Dermanyssus gallinae via High-Voltage Impulse

Dermanyssus gallinae, a parasitic mite that subsists on the avian blood of chickens, poses a considerable threat to the poultry industry. D. gallinae infestation can result in a plethora of detrimental effects for the host birds, including decreased egg production and anemia. Pyrethroid pesticides have been the primary means of combating this issue and have demonstrated high levels of efficacy. However, in recent years, D. gallinae has exhibited resistance to these chemicals, resulting in a marked decrease in their mortality; thus, an integrated control strategy in addition to the chemical use should be required for the sustainable control of this mite. This study confirms that D. gallinae can be effectively controlled through the utilization of high-voltage impulse discharges and that various electrical parameters possess optimal values that are required for mite control. The alterations in the body surface of the mite caused by high-voltage impulses were akin to those caused by heat, but no alteration in the elemental composition of the body surface was observed, suggesting a change in organization caused by currents flowing inside the exoskeleton. Comparatively, the mite control efficacy of high-voltage impulse was found to be substantially superior to that of ultraviolet light or ozone, with up to 95% more mites being killed in as little as 30 seconds.

Suppressive modulation of host immune responses by Dermanyssus gallinae infestation

The poultry red mite (Dermanyssus gallinae, PRM) is a blood-sucking ectoparasite in chickens and is one of the most serious threats to poultry farms. Mass infestation with PRMs causes various health problems in chickens, resulting in significant productivity reduction in the poultry industry. Infestation with hematophagous ectoparasites, such as ticks, induces host inflammatory and hemostatic reactions. On the other hand, several studies have reported that hematophagous ectoparasites secrete various immunosuppressants from their saliva to suppress host immune responses to maintain blood sucking. Here, we examined the expression of cytokines in peripheral blood cells to investigate whether PRM infestation affects immunological states in chickens. In PRM-infested chickens, anti-inflammatory cytokines, IL-10 and TGF-β1, and immune checkpoint molecules, CTLA-4 and PD-1, were highly expressed compared to noninfested chickens. PRM-derived soluble mite extracts (SME) upregulated the gene expression of IL-10 in peripheral blood cells and HD-11 chicken macrophages. In addition, SME suppressed the expression of interferons and inflammatory cytokines in HD-11 chicken macrophages. Moreover, SME induces the polarization of macrophages into anti-inflammatory phenotypes. Collectively, PRM infestation could affect host immune responses, especially suppress the inflammatory responses. Further studies are warranted to fully understand the influence of PRM infestation on host immunity.

Cross-sectional seasonal prevalence and relative risk of ectoparasitic infestations of rodents in North Sinai, Egypt.

Background and Aim:Rodents are ubiquitous animals that host ectoparasites and transmit zoonotic diseases. We conducted a cross-sectional study on the seasonal variation, period prevalence (Pp), and relative risk of ectoparasitic infestations in rodents collected in North Sinai, Egypt, from September 2019 to August 2020.Materials and Methods:We captured 380 rodents during the study period. Rodents were euthanized to perform species identification, and 2930 external parasites were collected and identified using light microscopic examination with systemic keys depending on morphological characters.Results:Rattus norvegicus (brown rat), Rattus rattus frugivorus (white-bellied rat), Rattus rattus alexandrines (gray-bellied rat), and Mus musculus domesticus (house mouse) were captured at the highest frequencies during summer (n=186), followed by spring (n=84), fall (n=71), and winter (n=39), with a higher proportion of males captured in all seasons. Analysis of the infestation Pp revealed highly significant increases (p<0.01) in ectoparasites during the winter. Temperature, humidity, and dew point were significantly (p<0.01) correlated with the numbers of captured and infested rodents. Parasitological examinations showed the higher risks of flea (Echidnophaga gallinacea, Xenopsylla cheopis, and Leptopsylla segnis) and lice (Hoplopleura hirsuta, Hoplopleura ocanthopus, Hoplopleura oenomydis, and Polyplax spinulosa) infestations during winter and mite (Laelaps nuttalli, Dermanyssus gallinae, Ornithonyssus bacoti, and Myobia musculi) infestations during summer.Conclusion:We conclude that ectoparasitic infestation prevalence and risk varies with predominating macroclimatic conditions. Strict preventive and biosecurity measures should be applied to combat rodent-related problems.

Phylogenetic Diversity of Dermanyssus gallinae (Dermanyssidae) based on Mitochondrial Cytochrome Oxidase-1 Gene Sequence Collected from Different Bird Species in Iran.

A wide range of hosts, especially birds, can be infested with Dermanyssus gallinae (D. gallinae), as an obligate hematophagous mite. In this study, cytochrome oxidase 1 (CO1) gene sequences were employed to perform molecular and phylogenetic analyses of D. gallinae collected from different bird species in Iran. Adult mites were collected from the body surface and cage material of ornamental and wild birds in industrial farms located in the Western and Northwestern regions of Iran. The infestation was identified in layer poultry farming by inspecting the eggs and the whole surfaces of the birds' bodies. The holding area and body surface of the ornamental and wild birds were also thoroughly examined. The D. gallinae samples were assigned to two subgroups of haplogroup A (i.e., A1 and A2). The phylogenetic tree suggested that the D. gallinae samples collected from wild birds in the A1 sub-haplogroup should be placed beside Japanese, Norwegian, Italian, and French samples isolated from wild birds in the A2 sub-haplogroup. Additionally, the highest phylogenetic similarity in the A2 sub-group was observed between mites isolated from ornamental and industrial birds in Australia. The findings of the present study suggest that crows and sparrows may play an important role in the transmission of D. gallinae infestation to other species of wild birds due to their high population, as well as their presence in most areas.

Assessment of fluralaner as a treatment in controlling Dermanyssus gallinae infestation on commercial layer farms and the potential for resulting benefits of improved bird welfare and productivity

BackgroundPoultry red mite (PRM) (Dermanyssus gallinae) infestations are a cause of anaemia, impaired productivity and stress-related behaviours linked to reduced hen welfare. A study investigated the potential health, welfare and productivity benefits following fluralaner treatment to eliminate PRM from infested hens.MethodsA PRM-infested layer house was selected on a free-range farm (5400 hens) and an aviary farm (42,400 hens). Fluralaner (Exzolt®; 0.5 mg/kg body weight) was administered twice, 7 days apart (Weeks 0 and 1), via drinking water. Mite populations were monitored by traps. Cameras recorded nighttime hen behaviours weekly, pre- and post-treatment. On the free-range farm, daytime behaviours were also recorded weekly. For pre- and post-treatment corticosterone assessments, eggs were randomly collected on both farms, and blood samples were collected from 50 randomly selected aviary farm hens. Production parameters were assessed using farm records.ResultsThroughout the post-treatment period, fluralaner efficacy against PRM was > 99% on both farms. On the aviary and free-range farms, treatment was followed by significant nighttime increases in the proportion of resting hens (P < 0.0001; P = 0.0175, respectively). Significant post-treatment versus pre-treatment nighttime reductions were observed in head shaking (aviary, P < 0.0001; free-range P = 0.0233) and preening (P = 0.0032; P = 0.0018) and on the aviary farm in bouts of body shaking (P = 0.0108), vertical wing shaking (P = 0.0002), head scratching (P = 0.0335), and gentle feather pecking (P < 0.0001). On the free-range farm there were significant daytime reductions in head scratching (P < 0.0001), head shaking (P = 0.0492) and preening (P = 0.0012). Relative to standard production parameters, no differences were detected on the aviary farm, but on the free-range farm the laying rate decline with increasing age was less than expected and the increase in egg weight greater than expected. Post-treatment increases in egg and plasma corticosterone were suggestive of stress factors in addition to mite infestation. Red blood cell counts and haematocrit increased following treatment.ConclusionFluralaner treatment eliminated mite challenge, leading to improved hen welfare and health, based on reductions in stress-related behaviours and restoration of the anaemia-inducing effects of mite blood feeding.Graphical

Dermanyssus gallinae and chickenegg production: impact, management, and a predicted compatibility matrix for integrated approaches.

The poultry red mite, Dermanyssus gallinae, is a worldwide threat to egg production and animal and human welfare. This mite is also a potential vector for several significant diseases. EU regulation that forbids the use of conventional cages for egg-laying hens may favour the growth of D. gallinae, a species known to thrive in more complex housing systems. Current control measures emphasize the use of chemical acaricides, which may have limited efficacy on D. gallinae considering its temporary blood-feeding behaviour. In integrated pest management (IPM), two or more compatible measures targeting physical, environmental, and/or biological aspects could be judiciously combined to enhance the effectiveness against D. gallinae infestation. To inform current and future IPM for D. gallinae, a compatibility matrix is proposed to guide the selection of control measures for field application.

A nonexhaustive overview on potential impacts of the poultry red mite (Dermanyssus gallinae) on poultry production systems.

The poultry red mite (PRM) (Dermanyssus gallinae) is a worldwide problem for the poultry production industry. Prevalence rates of more than 80% are common in many countries (Sparagano et al., 2009; Tomley and Sparagano, 2018). Complete development of D. gallinae, from egg to adult through one larval stage and two nymphal stages, typically occurs over 2 weeks. They usually feed for short periods and retrieve in cracks and crevices to digest blood contrary to other poultry mites. Economic costs associated with both control and production losses due to D. gallinae have been estimated at €130 million per year for the European Union egg industry. There is a relationship between D. gallinae infestation and hen mortality; some reports record a 10-fold increase in death rates following severe infestation in Romania (Cosoroaba, 2001). Although causal factors may vary, in extreme cases D. gallinae numbers may be so high that hens become severely anemic, with mortality resulting from exsanguination. At a sublethal level, mite feeding may result in significant stress to hens, causing an increase in circulating corticosterone and adrenaline and a decrease in β- and γ-globulins. Bird sleep patterns can be disrupted by the need for increased preening, and changes in head-scratching and feather-pecking behavior could also be seen. Increases in aggressive feather-pecking and cannibalistic behaviors have been reported. These mites can survive for weeks if not months without a blood meal and can therefore reappear between flocks. As blood feeders, PRMs could induce anemia with economic losses related to smaller egg size, less eggs per hen per year, and higher mortality. A recent report in Belgium followed various production parameters for fluralaner-treated bird groups compared to control groups, highlighting the positive impact of such treatment (Sleeckx et al., 2019). These mites can harbor key symbionts needed for their survival (de Luna et al., 2009) and can be responsible for the transmission of bacterial and viral diseases such as Salmonella (Valiente Moro et al., 2007; Hamidi et al., 2011; Sylejmani et al., 2016), Avian Influenza (Sommer et al., 2016), Coxiella burnetii, and Borrelia burgdorferi (Raele et al., 2018) which can also decimate flocks in their own rights (Sparagano et al., 2014).

Bacterial microbiota composition of a common ectoparasite of cavity‐breeding birds, the Hen Flea Ceratophyllus gallinae

Experimental field studies have demonstrated negative fitness consequences of Hen Flea Ceratophyllus gallinae infestations for bird hosts, yet it is currently unclear whether these negative effects are a direct consequence of flea‐induced blood loss or a result of flea‐borne pathogen transmission. Here we used a 16S rRNA gene sequencing approach to characterize the bacterial microbiota community of Hen Fleas collected from Great Tit Parus major nests and found that Brevibacterium (Actinobacteria), Staphylococcus (Firmicutes), Stenotrophomonas (Proteobacteria), Massilia (Proteobacteria), as well as the arthropod endosymbionts ‘Candidatus Lariskella’ and ‘Candidatus Midichloria’ were most abundant. We found evidence for the occurrence of Staphylococcus spp. in Hen Fleas, which may cause opportunistic infections in bird hosts, but not of other known pathogens commonly transmitted by other flea species, such as Bartonella spp. or Rickettsia spp. However, Hen Fleas might transmit other pathogens (e.g. viruses or bacteria that are not currently recognized as bird pathogens), which may contribute to the negative fitness consequences of Hen Flea infestations in addition to direct blood loss or secondary infections of wounds caused by biting fleas.

A sampling and estimation method for monitoring poultry red mite (Dermanyssus gallinae) infestation on caged-layer poultry farms.

BackgroundThe poultry red mite, Dermanyssus gallinae, is a serious problem in the laying hen industry worldwide. Currently, the foremost control method for D. gallinae is the implementation of integrated pest management, the effective application of which necessitates a precise monitoring method.ObjectivesThe aim of the study was to propose an accurate monitoring method with a reliable protocol for caged-layer poultry farms, and to suggest an objective classification for assessing D. gallinae infestation on caged-layer poultry farms according to the number of mites collected using the developed monitoring method.MethodsWe compared the numbers of mites collected from corrugated cardboard traps, regarding with length of sampling periods, sampling sites on cage, and sampling positions in farm buildings. The study also compared the mean numbers of mites collected by the developed method with the infestation levels using by the conventional monitoring methods in 37 caged-layer farm buildings.ResultsThe statistical validation provided the suitable monitoring method that the traps were installed for 2 days on feed boxes at 27 sampling points which included three vertical levels across nine equally divided zones of farms. Using this monitoring method, the D. gallinae infestation level can be assessed objectively on caged-layer poultry farms. Moreover, the method is more sensitive than the conventional method in detecting very small populations of mites.ConclusionsThis method can be used to identify the initial stages of D. gallinae infestation in the caged-layer poultry farms, and therefore, will contribute to establishment of effective control strategies for this mite.

Impact of Poultry Red Mite (Dermanyssus gallinae) Infestation on Blood Parameters of Laying Hens

The poultry red mite Dermanyssus gallinae is commonly acknowledged as a serious biological threat to global poultry breeding. This is mostly because of the inefficiency of acaricidal treatments of poultry houses, which does not eliminate the mite population, only constrains it. However, the impact of D. gallinae on poultry welfare is poorly characterized. The biochemical and cytological characteristics of infection are limited mainly to anaemia, decreased levels of triglycerides in the blood and eosinophilia. For the first time, we report the adverse effects of D. gallinae infestation of industrial poultry houses on the functional state of poultry livers. Treatment of poultry houses with acaricidal powder preparation, Wooran-dust 0.7%, containing synthetic pyrethroids (permethrin, S-fenvalerate and tetramethrin), led to the elimination of the mite population and resulted in normalization of most of the haematological and biochemical blood parameters (haemoglobin, erythrocytes, neutrophils, basophils, lymphocytes and AST). Increased eosinophils and ALT were the only indicators of infection in the blood of laying hens, and they remained above normal range until the 22nd day after the beginning of treatment with the acaricidal agent.

Dermanysuss gallinae attacks humans. Mind the gap!

ABSTRACTDermanyssus gallinae is a haematophagous ectoparasite primarily known as a pest of domestic and wild birds. It occasionally feeds on a range of mammals, and, more importantly, is of growing concern in human medicine. This review highlights mite attacks on people working with poultry, and updates the increasing incidence of dermanyssosis in urban environments in Europe. Although several cases of dermanyssosis have been documented, there are a number of reasons why diagnosis of D. gallinae infestations in humans is likely to be underestimated. Firstly, medical specialists are not well aware of D. gallinae infestations in humans. There is also a lack of collaboration with specialists from other disciplines. The problem is compounded by misdiagnoses and by the lack of diagnostic tools. We review the literature on human dermanyssosis cases in Europe, and also provide information on the epidemiology, clinical, histo-pathological and immunological aspects of dermanyssosis. We stress the need for improved recognition of this challenging infestation in humans, and provide straightforward recommendations for health practitioners, starting with collection of the correct anamnestic information and including appropriate management methods for case recognition and resolution. Finally, we indicate the most urgent areas to be addressed by future research.RESEARCH HIGHLIGHTSDermanyssus gallinae is of growing concern in human medicine.Most physicians are not well aware of dermanyssosis in humans.Bio-epidemiological and clinical aspects of this ectoparasitosis are highlighted.Practical key actions for diagnosis and correct management of infestation in humans are provided.

In vitro activity of fluralaner and commonly used acaricides against Dermanyssus gallinae isolates from Europe and Brazil

BackgroundThe poultry red mite Dermanyssus gallinae negatively impacts bird welfare and health, and interferes with egg production and quality, while emerging acaricide resistance limits control options. Fluralaner, a novel miticide for administration in drinking water, is approved for control of D. gallinae infestations. Mite sensitivity testing is relevant to gauge field isolate susceptibility to available treatments.MethodsThirteen D. gallinae isolates collected during 2014 through 2016 from farms in Germany, France, Spain and Brazil, and a 2001 laboratory-maintained isolate were used for acaricide contact sensitivity testing. Tested compounds were cypermethrin, deltamethrin, phoxim, propoxur, and the recently available acaricides, spinosad and fluralaner. In each study, at least one isolate was exposed to increasing concentrations of at least one acaricide. In one study, additional testing determined the sensitivity of the 2001 isolate to fluralaner using a mite-feeding test, and of fluralaner, phoxim and spinosad using an immersion test. At least two replicates were used for each dilution. Vehicle and untreated controls were also included.ResultsBased on 90% mortality (LC90) values, the laboratory isolate was susceptible to fluralaner (15.6–62.5 parts per million, ppm), phoxim (< 500 ppm), propoxur (< 125 ppm), and deltamethrin (500–1000 ppm). All field isolates remained sensitive to fluralaner concentrations ≤ 125 ppm. Spinosad LC90 values for laboratory and field isolates ranged between 2000–4000 ppm. For phoxim, relative to the laboratory isolate, there was reduced sensitivity of two German isolates (LC90 up to 4000 ppm) and two French isolates (> 4000 ppm). An isolate from Spain demonstrated reduced sensitivity to phoxim, propoxur and deltamethrin; an isolate from Brazil showed reduced sensitivity to propoxur and cypermethrin. Mite LC90 when exposed to fluralaner by blood feeding was < 0.1 ppm.ConclusionsContact sensitivity testing indicated apparent resistance to at least one of phoxim, deltamethrin, cypermethrin and propoxur in 13 field isolates from Europe and Brazil. All isolates were highly susceptible to fluralaner. Fluralaner was approximately 1000 times more active by feeding than by contact. Fluralaner’s distinct mode of action and efficacy against isolates largely refractory to those acaricides, makes it a promising option for the control of D. gallinae infestations of poultry.

Dermanyssus gallinae (Acari: Dermanyssidae) a cause of recurrent papular urticaria diagnosed by light and electron microscopy

Background: Papular urticaria is a prevalent disturbing condition manifested by chronic or recurring papules caused by a hypersensitivity response to the bites of mosquitoes, bedbugs, fleas, and other insects. D. gallinae was previously indicated as an etiological agent for papular urticaria and chronic itching by several researchers worldwide.Objective: To throw light on D. gallinae as a cause of papular urticaria in Upper Egypt discussing associating risk factors.Material and Methods: The present study evaluated patients attending the Dermatology Outpatient Clinic, Sohag University Hospitals, Egypt, and who were diagnosed as papular urticaria. Some patients with recurrent papular lesions gave history of exposure to domestic poultry or birds’ nests and insect bites. They were selected from 97 patients who complained of itching. They were advised to bring any insects suspected of biting them or that come in contact with their skin, which were then referred to the Parasitology Unit for identification by light (LM) and scanning electron microscopy (SEM).Results: The examined arthropods were identified as D. gallinae in thirty cases and human fleas in two cases. LM and SEM showed the remarkable identifying features of D. gallinae female. Contact with sources of infection (insects) either birds' nests or chicken husbandry was proved to be a risk factor for recurrent papular urticaria. Contact of the same family members to the same source of infection caused prevalence of arthropods borne recurrent papular urticaria among family members. Gender and residence were not associated risk factors.Conclusion: This is, to the best of our knowledge, the first repot of D. gallinae infestation in Egypt. Pruritic dermatitis caused by D. gallinae (associated with papules and vesicles) may sometimes be mistaken for scabies. Therefore, meticulous history recording, and environmental inspection are necessary to discover the etiology of recurrent papular urticaria.

Field efficacy and safety of fluralaner solution for administration in drinking water for the treatment of poultry red mite (Dermanyssus gallinae) infestations in commercial flocks in Europe

BackgroundWelfare concerns, production losses caused by Dermanyssus gallinae, the poultry red mite (PRM), and widespread mite resistance to environmentally applied acaricides continue to drive an urgent need for new and effective control measures. Fluralaner is a novel systemic acaricide developed to address that need. A series of field studies was initiated to investigate the safety and efficacy of a fluralaner solution (10 mg/ml) administered in drinking water at a dose rate of 0.5 mg/kg on two occasions with a 7-day interval, for treatment of natural PRM infestations in chickens.MethodsBlinded, negative-controlled studies were completed in Europe across eight layer, two breeder, and two replacement chicken farms. At each farm, two similar flocks were housed in similar PRM-infested units (either rooms within a building, or separate buildings) varying from 550 to 100,000 birds per unit. One unit at each farm was allocated to fluralaner treatment, administered in drinking water on Days 0 and 7. One unit remained untreated. Mite traps were placed throughout each unit on Days -1, 0 or 1, 3, 6, 9, and 13 or 14, then at weekly or two-weekly intervals, retrieved after 24 h and processed for mite counts. Efficacy at each farm was assessed by mean PRM count reductions from traps in treated units compared with those from control units. Production parameters and safety were also monitored.ResultsEfficacy was 95.3 to 99.8% on Day 3 and 97.8 to 100% on Day 9, thereafter remaining above 90% for 56 to 238 days after treatment initiation. Post-treatment improvement in egg-laying rate was greater by 0.9 to 12.6% in the treated group at 9 of the 10 layer or breeder farms. There were no treatment-related adverse events.ConclusionFluralaner administered at 0.5 mg/kg via drinking water twice, 7 days apart, was well tolerated and highly efficacious against the PRM in naturally infested chickens representing a range of production types and management systems. The results indicate that this novel treatment has potential to be the cornerstone of an integrated approach to reducing or eliminating the welfare and productivity costs of this increasingly threatening pest.

Experimental validation of the AVIVET trap, a tool to quantitatively monitor the dynamics of Dermanyssus gallinae populations in laying hens

Dermanyssus gallinae (D.gallinae) infestation causes economic losses due to impaired health and production of hens and costs of parasite control across the world. Moreover, infestations are associated with reduced welfare of hens and may cause itching in humans. To effectively implement control methods it is crucially important to have high quality information about the D. gallinae populations in poultry houses in space and time. At present no validated tool is available to quantitatively monitor the dynamics of all four stages of D.gallinae (i.e., eggs, larvae, nymphs, and adults) in poultry houses.This article describes the experimental validation of the AVIVET trap, a device to quantitatively monitor dynamics of D.gallinae infestations. We used the device to study D.gallinae in fully equipped cages with two white specific pathogen free Leghorn laying hens experimentally exposed to three different infestation levels of D.gallinae (low to high).The AVIVET trap was successfully able to detect D.gallinae at high (5,000 D.gallinae), medium (2,500 D.gallinae), and low (50 D.gallinae) level of D.gallinae infestation. The linear equation Y = 10∧ 10∧(0.47 + 1.21X) with Y = log10 (Total number of D.gallinae nymphs and adults) in the cage and X = log10 (Total number of D. gallinae nymphs and adults) in the AVIVET trap explained 93.8% of the variation.The weight of D.gallinae in the AVIVET trap also appears to be a reliable parameter for quantifying D.gallinae infestation in a poultry house. The weight of D.gallinae in the AVIVET trap correlates 99.6% (P < 0.000) to the counted number of all stages of D.gallinae in the trap (i.e., eggs, larvae, nymphs, and adults) indicating that the trap is highly specific.From this experiment it can be concluded that the AVIVET trap is promising as quantitative tool for monitoring D.gallinae dynamics in a poultry house.