House dust mite barrier bedding for childhood asthma: randomised placebo controlled trial in primary care [ISRCTN63308372].

PubMed

Sheikh, Aziz; Hurwitz, Brian; Sibbald, Bonnie; Barnes, Greta; Howe, Maggie; Durham, Stephen

2002-06-18

The house dust mite is the most important environmental allergen implicated in the aetiology of childhood asthma in the UK. Dust mite barrier bedding is relatively inexpensive, convenient to use, and of proven effectiveness in reducing mattress house dust mite load, but no studies have evaluated its clinical effectiveness in the control of childhood asthma when dispensed in primary care. We therefore aimed to evaluate the effectiveness of house dust mite barrier bedding in children with asthma treated in primary care. Pragmatic, randomised, double-blind, placebo controlled trial conducted in eight family practices in England. Forty-seven children aged 5 to 14 years with confirmed house dust mite sensitive asthma were randomised to receive six months treatment with either house dust mite barrier or placebo bedding. Peak expiratory flow was the main outcome measure of interest; secondary outcome measures included asthma symptom scores and asthma medication usage. No difference was noted in mean monthly peak expiratory flow, asthma symptom score, medication usage or asthma consultations, between children who received active bedding and those who received placebo bedding. Treating house dust mite sensitive asthmatic children in primary care with house dust mite barrier bedding for six months failed to improve peak expiratory flow. Results strongly suggest that the intervention made no impact upon other clinical features of asthma.

House dust mite barrier bedding for childhood asthma: randomised placebo controlled trial in primary care [ISRCTN63308372

PubMed Central

Sheikh, Aziz; Hurwitz, Brian; Sibbald, Bonnie; Barnes, Greta; Howe, Maggie; Durham, Stephen

2002-01-01

Background The house dust mite is the most important environmental allergen implicated in the aetiology of childhood asthma in the UK. Dust mite barrier bedding is relatively inexpensive, convenient to use, and of proven effectiveness in reducing mattress house dust mite load, but no studies have evaluated its clinical effectiveness in the control of childhood asthma when dispensed in primary care. We therefore aimed to evaluate the effectiveness of house dust mite barrier bedding in children with asthma treated in primary care. Methods Pragmatic, randomised, double-blind, placebo controlled trial conducted in eight family practices in England. Forty-seven children aged 5 to 14 years with confirmed house dust mite sensitive asthma were randomised to receive six months treatment with either house dust mite barrier or placebo bedding. Peak expiratory flow was the main outcome measure of interest; secondary outcome measures included asthma symptom scores and asthma medication usage. Results No difference was noted in mean monthly peak expiratory flow, asthma symptom score, medication usage or asthma consultations, between children who received active bedding and those who received placebo bedding. Conclusions Treating house dust mite sensitive asthmatic children in primary care with house dust mite barrier bedding for six months failed to improve peak expiratory flow. Results strongly suggest that the intervention made no impact upon other clinical features of asthma. PMID:12079502

MITEE: A Compact Ultralight Nuclear Thermal Propulsion Engine for Planetary Science Missions

NASA Astrophysics Data System (ADS)

Powell, J.; Maise, G.; Paniagua, J.

2001-01-01

A new approach for a near-term compact, ultralight nuclear thermal propulsion engine, termed MITEE (Miniature Reactor Engine) is described. MITEE enables a wide range of new and unique planetary science missions that are not possible with chemical rockets. With U-235 nuclear fuel and hydrogen propellant the baseline MITEE engine achieves a specific impulse of approximately 1000 seconds, a thrust of 28,000 newtons, and a total mass of only 140 kilograms, including reactor, controls, and turbo-pump. Using higher performance nuclear fuels like U-233, engine mass can be reduced to as little as 80 kg. Using MITEE, V additions of 20 km/s for missions to outer planets are possible compared to only 10 km/s for H2/O2 engines. The much greater V with MITEE enables much faster trips to the outer planets, e.g., two years to Jupiter, three years to Saturn, and five years to Pluto, without needing multiple planetary gravity assists. Moreover, MITEE can utilize in-situ resources to further extend mission V. One example of a very attractive, unique mission enabled by MITEE is the exploration of a possible subsurface ocean on Europa and the return of samples to Earth. Using MITEE, a spacecraft would land on Europa after a two-year trip from Earth orbit and deploy a small nuclear heated probe that would melt down through its ice sheet. The probe would then convert to a submersible and travel through the ocean collecting samples. After a few months, the probe would melt its way back up to the MITEE lander, which would have replenished its hydrogen propellant by melting and electrolyzing Europa surface ice. The spacecraft would then return to Earth. Total mission time is only five years, starting from departure from Earth orbit. Other unique missions include Neptune and Pluto orbiter, and even a Pluto sample return. MITEE uses the cermet Tungsten-UO2 fuel developed in the 1960's for the 710 reactor program. The W-UO2 fuel has demonstrated capability to operate in 3000 K hydrogen for many hours - a much longer period than the approximately one hour burn time for MITEE. Using this cermet fuel, and technology available from other nuclear propulsion programs, MITEE could be developed and ready for implementation in a relatively short time, i.e., approximately seven years. An overview description of the MITEE engine and its performance capabilities is provided.

United States Department of Agriculture-Agricultural Research Service research on managing insect resistance to insecticides.

PubMed

Elzen, Gary W; Hardee, Dick D

2003-01-01

Insecticide resistance has developed within many classes of pesticide, and over 500 species of insects and mites are resistant to one or more insecticides. Insecticide resistance and the consequent losses of food and fiber caused by failure to control insect and mite pests causes economic losses of several billion dollars worldwide each year. It is the goal of insect resistance management (IRM) to preserve useful pesticides by slowing, preventing or reversing development of resistance in pests. Important aspects of this goal are understanding the development of resistance and monitoring to determine ways to prevent its development. We describe programs specific to missions of the US Department of Agriculture, Agricultural Research Service, which are designed to characterize insecticide resistance in insects and mites with the goal of managing pests in an ecologically acceptable manner. Resistance management of cotton, potatoes, vegetables, melons, ornamentals, greenhouse crops, corn, stored grains, livestock, honeybees and mites, as well as management of transgenic crops are evaluated. We conclude that IRM is a vital part of stewardship of any pest management product and must be a combined effort of manufacturers, growers, consultants, extension services and grower organizations, working closely with regulators, to achieve logistically and economically feasible systems that prolong the effectiveness of all pest-control products.

Regular dorsal dimples and damaged mites of Varroa destructor in some Iranian honey bees (Apis mellifera).

PubMed

Ardestani, Masoud M; Ebadi, Rahim; Tahmasbi, Gholamhossein

2011-07-01

The frequency of damaged Varroa destructor Anderson and Trueman (Mesostigmata: Varroidae) found on the bottom board of hives of the honey bee, Apis mellifera L. (Hymenoptera: Apidae) has been used as an indicator of the degree of tolerance or resistance of honey bee colonies against mites. However, it is not clear that this measure is adequate. These injuries should be separated from regular dorsal dimples that have a developmental origin. To investigate damage to Varroa mites and regular dorsal dimples, 32 honey bee (A. mellifera) colonies were selected from four Iranian provinces: Isfahan, Markazi, Qazvin, and Tehran. These colonies were part of the National Honey bee Breeding Program that resulted in province-specific races. In April, Varroa mites were collected from heavily infested colonies and used to infest the 32 experimental colonies. In August, 20 of these colonies were selected (five colonies from each province). Adult bees from these colonies were placed in cages and after introducing mites, damaged mites were collected from each cage every day. The average percentage of injured mites ranged from 0.6 to 3.0% in four provinces. The results did not show any statistical differences between the colonies within provinces for injuries to mites, but there were some differences among province-specific lines. Two kinds of injuries to the mites were observed: injuries to legs and pedipalps, and injuries to other parts of the body. There were also some regular dorsal dimples on dorsal idiosoma of the mites that were placed in categories separate from mites damaged by bees. This type of classification helps identifying damage to mites and comparing them with developmental origin symptoms, and may provide criteria for selecting bees tolerant or resistant to this mite.

Overproduction of superoxide dismutase and catalase confers cassava resistance to Tetranychus cinnabarinus

PubMed Central

Lu, Fuping; Liang, Xiao; Lu, Hui; Li, Qian; Chen, Qing; Zhang, Peng; Li, kaimian; Liu, Guanghua; Yan, Wei; Song, Jiming; Duan, Chunfang; Zhang, Linhui

2017-01-01

To explore the role of protective enzymes in cassava (Manihot esculenta Crantz) resistance to mites, transgenic cassava lines overproducing copper/zinc superoxide dismutase (MeCu/ZnSOD) and catalase (MeCAT1) were used to evaluate and molecularly confirm cassava resistance to Tetranychus cinnabarinus. Laboratory evaluation demonstrated that, compared with the control cultivar TMS60444 (wild type, WT), the survival, reproduction, development and activities of SOD and CAT in T. cinnabarinus feeding on transgenic cassava lines SC2, SC4, and SC11 significantly inhibited. Furthermore, the activities of SOD and CAT in transgenic cassava lines SC2, SC4, and SC11 damaged by T. cinnabarinus significantly increased. These findings were similar to the results in the mite-resistant cassava cultivars. Besides, field evaluation indicated that the transgenic cassava lines SC2, SC4, and SC11 were slightly damaged as the highly mite-resistant control C1115, while the highly mite-susceptible WT was severely damaged by T. cinnabarinus. Laboratory and field evaluation demonstrated that transgenic cassava lines were resistant to T. cinnabarinus, which directly confirmed that the increase in SOD and CAT activities was positively related to cassava resistance to T. cinnabarinus. These results will help in understanding the antioxidant defense responses in the cassava–mite interaction and molecular breeding of mite-resistant cassava for effective pest control. PMID:28054665

The role of onion-associated fungi in bulb mite infestation and damage to onion seedlings.

PubMed

Ofek, Tal; Gal, Shira; Inbar, Moshe; Lebiush-Mordechai, Sara; Tsror, Leah; Palevsky, Eric

2014-04-01

In Israel Rhizoglyphus robini is considered to be a pest in its own right, even though the mite is usually found in association with fungal pathogens. Plant protection recommendations are therefore to treat germinating onions seedlings, clearly a crucial phase in crop production, when mites are discovered. The aim of this study was to determine the role of fungi in bulb mite infestation and damage to germinating onion seedlings. Accordingly we (1) evaluated the effect of the mite on onion seedling germination and survival without fungi, (2) compared the attraction of the mite to species and isolates of various fungi, (3) assessed the effect of a relatively non-pathogenic isolate of Fusarium oxysporum on mite fecundity, and (4) determined the effects of the mite and of F. oxysporum separately and together, on onion seedling germination and sprout development. A significant reduction of seedling survival was recorded only in the 1,000 mites/pot treatment, after 4 weeks. Mites were attracted to 6 out of 7 collected fungi isolates. Mite fecundity on onion sprouts infested with F. oxysporum was higher than on non-infested sprouts. Survival of seedlings was affected by mites, fungi, and their combination. Sprouts on Petri dishes after 5 days were significantly longer in the control and mite treatments than both fungi treatments. During the 5-day experiment more mites were always found on the fungi-infected sprouts than on the non-infected sprouts. Future research using suppressive soils to suppress soil pathogens and subsequent mite damage is proposed.

Seasonal dynamics of mites and fungi and their interaction with southern pine beetle

Treesearch

Richard W. Hofstetter; Keir D. Klepzig; John C. Moser; Matthew P. Ayres

2006-01-01

We evaluated whether Dendroctonus fiontalis Zimmermann populations were influenced by nontrophic interactions involving commensal mites, their mutualistic bluestain fungus Ophiostoma minus (Hedgc.) H. and P. Sydow, and beetle-mutualistic mycangial fungi. We tested for effects of delayed, nonlinear, or positive feedback from O. minus and mites on

Foliar nectar enhances plant–mite mutualisms: the effect of leaf sugar on the control of powdery mildew by domatia-inhabiting mites

PubMed Central

Weber, Marjorie G.; Porturas, Laura D.; Taylor, Scott A.

2016-01-01

Background and Aims Mite domatia are small structures on the underside of plant leaves that provide homes for predacious or fungivorous mites. In turn, mites inhabiting domatia defend the plant by consuming leaf herbivores and pathogens, which can result in a domatia-mediated, plant–mite defence mutualism. Several recent studies have suggested that plants receive enhanced benefits when they provide a foliar food source, such as sugars secreted from extrafloral nectaries, to mite mutualists alongside mite domatia. However, the effect of foliar sugar on reducing leaf pathogen load via domatia-inhabiting mites has not been directly investigated. Methods To fill this gap, the links between foliar sugar addition, domatia-inhabiting mite abundance, and pathogen load were experimentally evaluated in wild grape. Furthermore, because the proposed combined benefits of providing food and housing have been hypothesized to select for the evolutionary correlation of extrafloral nectaries and domatia across plant lineages, a literature survey aimed at determining the overlap of mite domatia and extrafloral nectaries across plant groups was also conducted. Key Results It was found that leaves with artificial addition of foliar sugar had 58–80 % more mites than leaves without foliar sugar addition, and that higher mite abundances translated to reduced powdery mildew (Erysiphe necator) loads on leaves. It was found that mite domatia and extrafloral nectaries occur non-randomly in the same clades across Eudicots. Genera with both traits are reported to highlight candidate lineages for future studies. Conclusions Together, the results demonstrate that foliar sugar can indeed enhance the efficacy of domatia-mediated plant–mite mutualisms, and suggest that this synergism has the potential to influence the co-distribution of foliar nectar and mite domatia across plants. PMID:27343230

The role of volatiles in aggregation and host-seeking of the haematophagous poultry red mite Dermanyssus gallinae (Acari: Dermanyssidae).

PubMed

Koenraadt, C J M; Dicke, M

2010-03-01

Infestations with ectoparasitic poultry red mites (Dermanyssus gallinae) pose an increasing threat to poultry health and welfare. Because of resistance to acaricides and higher scrutiny of poultry products, alternative and environmentally safe management strategies are warranted. Therefore, we investigated how volatile cues shape the behavior of D. gallinae and how this knowledge may be exploited in the development of an attract-and-kill method to control mite populations. A Y-tube olfactometer bio-assay was used to evaluate choices of mites in response to cues related to conspecific mites as well as related to their chicken host. Both recently fed and starved mites showed a strong preference (84 and 85%, respectively) for volatiles from conspecific, fed mites as compared to a control stream of clean air. Mites were also significantly attracted to 'aged feathers' (that had remained in the litter for 3-4 days), but not to 'fresh feathers'. Interestingly, an air stream containing 2.5% CO(2), which mimics the natural concentration in air exhaled by chickens, did attract fed mites, but inhibited the attraction of unfed mites towards volatiles from aged feathers. We conclude that both mite-related cues (aggregation pheromones) and host-related cues (kairomones) mediate the behavior of the poultry mite. We discuss the options to exploit this knowledge as the 'attract' component of attract-and-kill strategies for the control of D. gallinae.

Low temperature–scanning electron microscopy to evaluate morphology and predation of Scolothrips sexmaculatus Pergande (Thysanoptera: Thripidae) against spider mites (Acari: Tetranychidae: Tetranychus species)

USDA-ARS?s Scientific Manuscript database

This paper evaluates the potential usefulness of low temperature-scanning electron microscopy (LT-SEM) to evaluate morphology and predation behavior of the six-spotted thrips (Scolothrips sexmaculatus Pergande) against the two-spotted spider mite (Tetranychus urticae (Koch)). Morphological features...

Status of Aceria guerreronis Keifer (Acari: Eriophyidae) as a pest of coconut in the state of Sao Paulo, southeastern Brazil.

PubMed

Oliveira, D C; de Moraes, G J; Dias, C T S

2012-08-01

The coconut mite, Aceria guerreronis Keifer, is one of the main pests of coconut palms (Cocos nucifera) in northeastern Brazil. The objective of this study was to evaluate the levels of the coconut mite and other mites on coconut palms in the state of São Paulo and to estimate the possible role of predatory mites in the control of this pest. The effect of cultivated genotypes and sampling dates on the mite populations was also estimated. We sampled attached fruits, leaflets, inflorescences, and fallen fruits. The coconut mite was the main phytophagous mite found on attached and fallen fruits, with average densities of 110.0 and 20.5 mites per fruit, respectively. The prevalent predatory mites on attached and fallen fruits were Proctolaelaps bulbosus Moraes, Reis & Gondim Jr. and Proctolaelaps bickleyi (Bram), both Melicharidae. On leaflets, the tenuipalpids Brevipalpus phoenicis (Geijsks) and Tenuipalpus coyacus De Leon and the tetranychid Oligonychus modestus (Banks) were the predominant phytophagous mites. On both leaflets and inflorescences, the predominant predatory mites belonged to the Phytoseiidae. Neoseiulus baraki (Athias-Henriot) and Neoseiulus paspalivorus (De Leon), predators widely associated with the coconut mite in northeastern Brazil and several other countries, were not found. The low densities of the coconut mite in São Paulo could be related to prevailing climatic conditions, scarcity of coconut plantations (hampering the dispersion of the coconut mite between fields), and to the fact that some of the genotypes cultivated in the region are unfavorable for its development.

Functional responses and prey-stage preferences of a predatory gall midge and two predacious mites wtih twospotted spider mites, Tetranychus urticae as host

USDA-ARS?s Scientific Manuscript database

The twospotted spider mite, Tetranychus urticae (Acari: Tetranychidae), is an important pest of vegetables and other crops. This study was conducted to evaluate and compare the potential role of three commercially available predators, predatory gall midge, Feltiella acarisuga (Vallot) (Diptera: Ceci...

Integrated pest management of two-spotted mite Tetranychus urticae on greenhouse roses using petroleum spray oil and the predatory mite Phytoseiulus persimilis.

PubMed

Nicetic; Watson, D M; Beattie, G A; Meats, A; Zheng, J

2001-01-01

From 1995 to 1999, four experiments were conducted on greenhouse roses to assess the effectiveness of the nC24 petroleum spray oil (PSO), D-C-Tron Plus, against two-spotted mite, Tetranychus urticae Koch (Acarina: Tetranychidae), and to determine how the oil could be most efficiently and effectively used in combination with the predatory mite Phytoseiulus persimilis Athias-Henriot (Acarina: Phytoseiidae) in an integrated pest management program. The results showed that 0.5% PSO applied fortnightly to roses gave excellent protection from T urticae infestation when the mite population was not already established. However, PSO applied after roses were infested with T. urticae above the economic threshold only stabilised populations without reducing them below that threshold. Populations of P. persimilis in the upper and lower canopies were unchanged after two sprays of PSO at 7-day intervals, and application of PSO to the upper canopy was as effective in controlling T. urticae in the presence of P persimilis as spraying the entire plant. Combining PSO with P. persimilis gave better control of T. urticae than using P. persimilis alone. The most cost-effective use of PSO in the presence of P. persimilis is, therefore, to apply spray only to the upper canopy. This will not affect control of powdery mildew with PSO. Comparison of a control program for T urticae based on the monitored use of synthetic miticides with that based on calendar application of PSO revealed that both gave equally effective control. The benefits of combining PSO and P. persimilis in an integrated pest management program for T. urticae on roses over a program based on synthetic fungicides are discussed.

Beyond insects: current status, achievements and future perspectives of RNAi in mite pests.

PubMed

Niu, Jinzhi; Shen, Guangmao; Christiaens, Olivier; Smagghe, Guy; He, Lin; Wang, Jinjun

2018-05-11

Mites comprise a group of key agricultural pests on a wide range of crops. They cause harm through feeding on the plant and transferring dangerous pathogens, and the rapid evolution of pesticide resistance in mites highlights the need for novel control methods. Currently, RNA interference (RNAi) shows a great potential for insect pest control. Here, we review the literature associated with RNAi in mite pests. We discuss different target genes and RNAi efficiency in various mite species, a promising Varroa control program through RNAi, the synergy of RNAi with plant defense mechanisms and microorganisms, and the current understandings of systemic movement of dsRNA. Based on this, we can conclude that there is a clear potential for an RNAi-based mite control application but further research on several aspects is needed, including: (i) the factors influencing the RNAi efficiency, (ii) the mechanism of environmental RNAi and cross-kingdom dsRNA trafficking, (iii) the mechanism of possible systemic and parental RNAi, and (iv) non-target effects, specifically in predatory mites, should be considered during the RNAi target selection. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Toxicity of six insecticides to predatory mite Amblyseius cucumeris (Oudemans) (Acari: Phytoseiidae) in- and off-field.

PubMed

Cheng, Shenhang; Lin, Ronghua; Zhang, Nan; Yuan, Shankui; Zhou, Xinxin; Huang, Jian; Ren, Xiaodong; Wang, Shoushan; Jiang, Hui; Yu, Caihong

2018-06-22

Amblyseius cucumeris (Oudemans) is a beneficial non-target arthropod (NTA) and a key predator of tetranychid mites in integrated pest management (IPM) programs across China. Evaluating the toxic effects of insecticides on such predatory mites is essential for the success and development of IPM. We tested six insecticides to determine the risk of neonicotinoid insecticide toxicity to predatory mites, using the 'open glass plate method' and adult female A. cucumeris in a "worst case laboratory exposure" scenario. A 48-h toxicity test was performed using the hazard quotient (HQ) approach to evaluate the risk of each insecticide. The LR 50 values (application rate that caused 50% mortality) of acetamiprid, thiamethoxam, imidacloprid, and dinotefuran were 76.4, 104.5, 84.9, and 224.6 g active ingredient (a.i.) ha -1 , respectively, with in-field HQ values of 0.40, 1.28, 0.49, and 0.82, respectively. The HQ values were lower than the trigger value of 2, and were consistent with off-field values. The risks of the four neonicotinoid insecticides to adult female A. cucumeris were acceptable in two exposure scenarios in field and off field. The 48-h LR 50 values for bifenthrin and malathion were 0.008 and 0.062 g. a.i. ha -1 , respectively, which were much lower than the recommended field application rates. The HQ values were much higher than the trigger values for both in- and off-field, indicating that the risks of these two insecticides were unacceptable. Bifenthrin and malathion posed an extremely high risk to the test species, and their use should be restricted to reduce risks to the field with augmentative releases of A. cucumeris. Copyright © 2018 Elsevier Inc. All rights reserved.

Identification of developmentally-specific kinotypes and mechanisms of Varroa mite resistance through whole-organism, kinome analysis of honeybee

PubMed Central

Robertson, Albert J.; Trost, Brett; Scruten, Erin; Robertson, Thomas; Mostajeran, Mohammad; Connor, Wayne; Kusalik, Anthony; Griebel, Philip; Napper, Scott

2014-01-01

Recent investigations associate Varroa destructor (Mesostigmata: Varroidae) parasitism and its associated pathogens and agricultural pesticides with negative effects on colony health, resulting in sporadic global declines in domestic honeybee (Apis mellifera) populations. These events have motivated efforts to develop research tools that can offer insight into the causes of declining bee health as well as identify biomarkers to guide breeding programs. Here we report the development of a bee-specific peptide array for characterizing global cellular kinase activity in whole bee extracts. The arrays reveal distinct, developmentally-specific signaling profiles between bees with differential susceptibility to infestation by Varroa mites. Gene ontology analysis of the differentially phosphorylated peptides indicates that the differential susceptibility to Varroa mite infestation does not reflect compromised immunity; rather, there is evidence for mite-mediated immune suppression within the susceptible phenotype that may reduce the ability of these bees to counter secondary viral infections. This hypothesis is supported by the demonstration of more diverse viral infections in mite-infested, susceptible adult bees. The bee-specific peptide arrays are an effective tool for understanding the molecular basis of this complex phenotype as well as for the discovery and utilization of phosphorylation biomarkers for breeding programs. PMID:24904639

Weed management practices affect the diversity and relative abundance of physic nut mites.

PubMed

Saraiva, Althiéris de Sousa; Sarmento, Renato A; Erasmo, Eduardo A L; Pedro-Neto, Marçal; de Souza, Danival José; Teodoro, Adenir V; Silva, Daniella G

2015-03-01

Crop management practices determine weed community, which in turn may influence patterns of diversity and abundance of associated arthropods. This study aimed to evaluate whether local weed management practices influence the diversity and relative abundance of phytophagous and predatory mites, as well as mites with undefined feeding habits--of the families Oribatidae and Acaridae--in a physic nut (Jatropha curcas L.) plantation subjected to (1) within-row herbicide spraying and between-row mowing; (2) within-row herbicide spraying and no between-row mowing; (3) within-row weeding and between-row mowing; (4) within-row weeding and no between-row mowing; and (5) unmanaged (control). The herbicide used was glyphosate. Herbicide treatments resulted in higher diversity and relative abundance of predatory mites and mites with undefined feeding habit on physic nut shrubs. This was probably due to the toxic effects of the herbicide on mites or to removal of weeds. Within-row herbicide spraying combined with between-row mowing was the treatment that most contributed to this effect. Our results show that within-row weeds harbor important species of predatory mites and mites with undefined feeding habit. However, the dynamics of such mites in the system can be changed according to the weed management practice applied. Among the predatory mites of the family Phytoseiidae Amblydromalus sp. was the most abundant, whereas Brevipalpus phoenicis was the most frequent phytophagous mite and an unidentified oribatid species was the most frequent mite with undefined feeding habit.

Inactivation of dust mites, dust mite allergen, and mold from carpet.

PubMed

Ong, Kee-Hean; Lewis, Roger D; Dixit, Anupma; MacDonald, Maureen; Yang, Mingan; Qian, Zhengmin

2014-01-01

Carpet is known to be a reservoir for biological contaminants, such as dust mites, dust mite allergen, and mold, if it is not kept clean. The accumulation of these contaminants in carpet might trigger allergies or asthma symptoms in both children and adults. The purpose of this study is to compare methods for removal of dust mites, dust mite allergens, and mold from carpet. Carpets were artificially worn to simulate 1 to 2 years of wear in a four-person household. The worn carpets were inoculated together with a common indoor mold (Cladosporium species) and house dust mites and incubated for 6 weeks to allow time for dust mite growth on the carpet. The carpets were randomly assigned to one of the four treatment groups. Available treatment regimens for controlling carpet contaminants were evaluated through a literature review and experimentation. Four moderately low-hazard, nondestructive methods were selected as treatments: vacuuming, steam-vapor, Neem oil (a natural tree extract), and benzalkonium chloride (a quaternary ammonium compound). Steam vapor treatment demonstrated the greatest dust mite population reduction (p < 0.05) when compared to other methods. The two physical methods, steam vapor and vacuuming, have no statistically significant efficacy in inactivating dust mite allergens (p = 0.084), but have higher efficacy when compared to the chemical method on dust mite allergens (p = 0.002). There is no statistically significant difference in the efficacy for reducing mold in carpet (p > 0.05) for both physical and chemical methods. The steam-vapor treatment effectively killed dust mites and denatured dust mite allergen in the laboratory environment.

Effects of bleach activator, sodium alkyl acyloxybenzene sulfonate, on house dust mites (Dermatophagoides farinae).

PubMed

Tobe, Seiichi; Kamezaki, Hiroki; Watanabe, Toshiyuki; Takaoka, Hiromitsu; Sakaguchi, Masahiro

2010-01-01

House dust mites (Dermatophagoides farinae) in bedding and clothes are a major allergen. However, house dust mites cannot be killed by general washing conditions under 50 degrees C. Therefore, low-temperature washing conditions must be improved to eliminate house dust mites. Sodium alkyl acyloxybenzene sulfonate (OBS) is a bleach activator that is used to intensify the bleaching effects of some laundry products. The purpose of this study was to evaluate the effect of OBS on the elimination of house dust mites in low-temperature washing conditions. D. farinae was soaked in solutions containing different types of OBS for various durations and at various temperatures. The miticidal effects of the various washing conditions were also evaluated for D. farinae. Then sodium lauroyloxybenzene sulfonate (OBS-12) produced the highest D. farinae mortality rate among the OBS solutions that were examined and had a stronger miticidal effect than available chlorine under general washing conditions. OBS exhibited miticidal effects under general washing conditions at low temperatures. Since OBS is already used as an additive in some laundry products to increase the bleaching activity, OBS can be easily used to kill house dust mites under general washing conditions.

Simplified methods of evaluating colonies for levels of Varroa Sensitive Hygiene (VSH)

USDA-ARS?s Scientific Manuscript database

Varroa sensitive hygiene (VSH) is a trait of honey bees, Apis mellifera, that supports resistance to varroa mites, Varroa destructor. Components of VSH were evaluated to identify simple methods for selection of the trait. Varroa mite population growth was measured in colonies with variable levels of...

Foliar nectar enhances plant-mite mutualisms: the effect of leaf sugar on the control of powdery mildew by domatia-inhabiting mites.

PubMed

Weber, Marjorie G; Porturas, Laura D; Taylor, Scott A

2016-09-01

Mite domatia are small structures on the underside of plant leaves that provide homes for predacious or fungivorous mites. In turn, mites inhabiting domatia defend the plant by consuming leaf herbivores and pathogens, which can result in a domatia-mediated, plant-mite defence mutualism. Several recent studies have suggested that plants receive enhanced benefits when they provide a foliar food source, such as sugars secreted from extrafloral nectaries, to mite mutualists alongside mite domatia. However, the effect of foliar sugar on reducing leaf pathogen load via domatia-inhabiting mites has not been directly investigated. To fill this gap, the links between foliar sugar addition, domatia-inhabiting mite abundance, and pathogen load were experimentally evaluated in wild grape. Furthermore, because the proposed combined benefits of providing food and housing have been hypothesized to select for the evolutionary correlation of extrafloral nectaries and domatia across plant lineages, a literature survey aimed at determining the overlap of mite domatia and extrafloral nectaries across plant groups was also conducted. It was found that leaves with artificial addition of foliar sugar had 58-80 % more mites than leaves without foliar sugar addition, and that higher mite abundances translated to reduced powdery mildew (Erysiphe necator) loads on leaves. It was found that mite domatia and extrafloral nectaries occur non-randomly in the same clades across Eudicots. Genera with both traits are reported to highlight candidate lineages for future studies. Together, the results demonstrate that foliar sugar can indeed enhance the efficacy of domatia-mediated plant-mite mutualisms, and suggest that this synergism has the potential to influence the co-distribution of foliar nectar and mite domatia across plants. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A review on the factors affecting mite growth in stored grain commodities.

PubMed

Collins, D A

2012-03-01

A thorough review of the literature has identified the key factors and interactions that affect the growth of mite pests on stored grain commodities. Although many factors influence mite growth, the change and combinations of the physical conditions (temperature, relative humidity and/or moisture content) during the storage period are likely to have the greatest impact, with biological factors (e.g. predators and commodity) playing an important role. There is limited information on the effects of climate change, light, species interactions, local density dependant factors, spread of mycotoxins and action thresholds for mites. A greater understanding of these factors may identify alternative control techniques. The ability to predict mite population dynamics over a range of environmental conditions, both physical and biological, is essential in providing an early warning of mite infestations, advising when appropriate control measures are required and for evaluating control measures. This information may provide a useful aid in predicting and preventing mite population development as part of a risk based decision support system.

Treatment of mites folliculitis with an ornidazole-based sequential therapy: A randomized trial.

PubMed

Luo, Yang; Sun, Yu-Jiao; Zhang, Li; Luan, Xiu-Li

2016-07-01

Treatment of Demodex infestations is often inadequate and associated with low effective rate. We sought to evaluate the efficacy of an ornidazole-based sequential therapy for mites folliculitis treatment. Two-hundred patients with mites folliculitis were sequentially treated with either an ornidazole- or metronidazole-based regimen. Sebum cutaneum was extruded from the sebaceous glands of each patient's nose and the presence of Demodex mites were examined by light microscopy. The clinical manifestations of relapse of mites folliculitis were recorded and the subjects were followed up at 2, 4, 8, and 12 weeks post-treatment. Patients treated with the ornidazole-based regimen showed an overall effective rate of 94.0%. Additionally, at the 2, 4, 8, and 12-week follow-up, these patients had significantly lower rates of Demodex mite relapse and new lesion occurrence compared with patients treated with the metronidazole-based regimen (P < 0.05). Sequential therapy using ornidazole, betamethasone, and recombinant bovine basic fibroblast growth factor (rbFGF) gel is highly effective for treating mites folliculitis.

Factors influencing the prevalence and infestation levels of Varroa destructor in honeybee colonies in two highland agro-ecological zones of Uganda.

PubMed

Chemurot, Moses; Akol, Anne M; Masembe, Charles; de Smet, Lina; Descamps, Tine; de Graaf, Dirk C

2016-04-01

Varroa mites are ecto-parasites of honeybees and are a threat to the beekeeping industry. We identified the haplotype of Varroa mites and evaluated potential factors that influence their prevalence and infestation levels in the eastern and western highland agro-ecological zones of Uganda. This was done by collecting samples of adult worker bees between December 2014 and September 2015 in two sampling moments. Samples of bees were screened for Varroa using the ethanol wash method and the mites were identified by molecular techniques. All DNA sequences obtained from sampled mite populations in the two zones were 100 % identical to the Korean Haplotype (AF106899). Mean mite prevalence in the apiaries was 40 and 53 % for the western and eastern zones, respectively, during the first sampling. Over the second sampling, mean mite prevalence increased considerably in the western (59 %) but not in the eastern (51 %) zone. Factors that were associated with Varroa mite infestation levels include altitude, nature of apiary slope and apiary management practices during the first sampling. Our results further showed that Varroa mites were spreading from lower to higher elevations. Feral colonies were also infested with Varroa mites at infestation levels not significantly different from those in managed colonies. Colony productivity and strength were not correlated to mite infestation levels. We recommend a long-term Varroa mite monitoring strategy in areas of varying landscape and land use factors for a clear understanding of possible changes in mite infestation levels among African honeybees for informed decision making.

Development of a user-friendly delivery method for the fungus Metarhizium anisopliae to control the ectoparasitic mite Varroa destructor in honey bee, Apis mellifera, colonies.

PubMed

Kanga, Lambert H B; Adamczyk, John; Patt, Joseph; Gracia, Carlos; Cascino, John

2010-12-01

A user-friendly method to deliver Metarhizium spores to honey bee colonies for control of Varroa mites was developed and tested. Patty blend formulations protected the fungal spores at brood nest temperatures and served as an improved delivery system of the fungus to bee hives. Field trials conducted in 2006 in Texas using freshly harvested spores indicated that patty blend formulations of 10 g of conidia per hive (applied twice) significantly reduced the numbers of mites per adult bee, mites in sealed brood cells, and residual mites at the end of the 47-day experimental period. Colony development in terms of adult bee populations and brood production also improved. Field trials conducted in 2007 in Florida using less virulent spores produced mixed results. Patty blends of 10 g of conidia per hive (applied twice) were less successful in significantly reducing the number of mites per adult bee. However, hive survivorship and colony strength were improved, and the numbers of residual mites were significantly reduced at the end of the 42-day experimental period. The overall results from 2003 to 2008 field trials indicated that it was critical to have fungal spores with good germination, pathogenicity and virulence. We determined that fungal spores (1 × 10(10) viable spores per gram) with 98% germination and high pathogenicity (95% mite mortality at day 7) provided successful control of mite populations in established honey bee colonies at 10 g of conidia per hive (applied twice). Overall, microbial control of Varroa mite with M. anisopliae is feasible and could be a useful component of an integrated pest management program.

In vitro and field studies on the contact and fumigant toxicity of a neem-product (Mite-Stop) against the developmental stages of the poultry red mite Dermanyssus gallinae.

PubMed

Locher, Nina; Al-Rasheid, Khaled A S; Abdel-Ghaffar, Fathy; Mehlhorn, Heinz

2010-07-01

The acaricidal activity of the neem product MiteStop was investigated for its potential use as a botanical acaricide for the control of the poultry red mite Dermanyssus gallinae. This neem product is a special formulation of an extract of the seeds of the neem tree Azadirachta indica A. Juss. The efficacy was tested under laboratory conditions as well as in poultry houses. Four different methods of application were used in a filter paper bioassay to evaluate contact and vapour phase toxicity tests. The neem product proved to be already active in very small doses. In order to investigate the efficacy under field conditions, a poultry house was sprayed twice within a 7-day period using 1:33 and 1:50 diluted MiteStop. Cardboard traps were used to assess the mite population before, during and after the treatment. The mite population could be reduced by 89%. In a second poultry house, the spraying of defined areas with a 1:30, 1:33 or 1:50 dilution of the acaricide proved to be highly efficacious against all mite stages. Three other field trials proved that MiteStop is highly active against the red poultry mite. The most efficient dilution is 1:33 with tap water and spraying two or three times at intervals of 7 days.

Remote sensing evaluation of twospotted spider mite damage on greenhouse cotton

USDA-ARS?s Scientific Manuscript database

Two-spotted spider mite, Tetranychus urticae Koch, is a polyphagous pest which occurs on a variety of field and horticultural crops. It often becomes an early season pest of cotton in damaging proportions from being a late season innocuous pest in the mid-southern United States. Evaluation of acari...

Sensitization of Children to Storage Mites in Kutahya, Turkey

PubMed Central

Soyucen, Erdogan

2009-01-01

Specific IgE against Acarus siro, Glycphagus domesticus, Tyrophagus putrescentiae, and Lepidoglyphus destructor have been investigated by ELISA in sera of 92 children. Of them, 41 were found to be specific IgE positive (≥ 0.35 IU/ml) against at least one of house dust mite species, Dermatophagoides pteronyssinus and Dermatophagoides farinae, by an immunoblot. In 65.9% of the dust mite-sensitized children, specific IgE against at least one of these mite species was found. Sensitization levels, including co-sensitization cases were found to be 35.7% against A. siro, 24.4% against T. putrescentiae, 31.7% against L. destructor, and 26.8% against G. domesticus. In non-sensitized children, dust mite sensitization level was found to be 25.5%. Breakdown of sensitization by individual species in this group was; against A. siro and T. putrescentiae at 7.8%, against L. destructor at 13.7%, and against G. domesticus at 9.8%. When all children were reckoned, 43.5% was found to be sensitized against at least one storage mite species, with sensitizations against A. siro at 18.5%, T. putrescentiae at 26.1%, L. destructor at 21.7%, and G. domesticus at 17.4%. In dust samples collected from the dwellings of children, distribution of species was found to be A. siro (17%), G. domesticus (23%), T. putrescentiae (29%), L. destructor (25%), and unidentified (6%). In Fisher's chi-square test on SPSS program, there was a relationship between dust mite sensitization and storage mite sensitization (P < 0.05), but no meaningful relationship was found on the basis of individual mite species. PMID:19967087

Storage mite contamination of commercial dry dog food in south-eastern Australia.

PubMed

Hibberson, C E; Vogelnest, L J

2014-06-01

To evaluate contamination of unopened and opened stored sources of commercial dry dog food by viable storage mites. Prospective laboratory and field study. Samples were collected from nine brands of previously unopened bags (new bags) of dry food and 20 field sources of stored dry food in homes in Sydney and Canberra, Australia. All samples were initially examined for the presence of mites using a stereo-binocular microscope and then placed in separate filter-paper-sealed containers. Field samples were incubated at an average temperature of 29°C and 78% relative humidity (RH) for 5 weeks and then at average 26°C/83% RH for 8 weeks. Paired new-bag samples were stored under room conditions (average 23°C/47% RH) and controlled incubator conditions (average 26°C/80% RH) for 6 weeks. All samples were thoroughly examined for mites, mite eggs and visible mould once weekly using a stereo-binocular microscope. Storage mites were not visualised in any of the field samples or in new-bag samples stored at room temperature. Storage mites, identified as Tyrophagus putrescentiae, were visualised in increasing numbers in seven of nine new-bag samples after incubation, with first mites and then eggs evident after 3 weeks of incubation. We confirmed the presence of viable storage mites in a range of previously unopened commercial dry dog foods in Australia and confirmed the possibility of heavy storage mite contamination for dry food stored under conditions of moderate temperature and high humidity. These findings have relevance to storage mite and/or dust mite sensitivity in canine atopic dermatitis. © 2014 Australian Veterinary Association.

Sublingual immunotherapy in patients with house dust mite allergic rhinitis: prospective study of clinical outcomes over a two-year period.

PubMed

Soh, J Y; Thalayasingam, M; Ong, S; Loo, E X L; Shek, L P; Chao, S S

2016-03-01

Sublingual immunotherapy in patients with allergic rhinitis sensitised to house dust mites is safe, but its efficacy is controversial and sublingual immunotherapy with Blomia tropicalis has not yet been studied. This study sought to evaluate the efficacy of sublingual immunotherapy with house dust mite extract in children and adults with house dust mite allergic rhinitis over a period of two years. A prospective observational study was conducted of children and adults diagnosed with house dust mite allergic rhinitis who were treated with sublingual immunotherapy from 2008 to 2012. Total Nasal Symptom Scores, Mini Rhinoconjunctivitis Quality of Life scores and medication usage scores were assessed prospectively. Thirty-nine patients, comprising 24 children and 15 adults, were studied. Total Nasal Symptom Scores and Mini Rhinoconjunctivitis Quality of Life scores dropped significantly at three months into therapy, and continued to improve. Medication usage scores improved at one year into immunotherapy. Sublingual immunotherapy with house dust mite extracts, including B tropicalis, is efficacious as a treatment for patients with house dust mite allergic rhinitis.

Treatment of mites folliculitis with an ornidazole-based sequential therapy

PubMed Central

Luo, Yang; Sun, Yu-Jiao; Zhang, Li; Luan, Xiu-Li

2016-01-01

Abstract Objective: Treatment of Demodex infestations is often inadequate and associated with low effective rate. We sought to evaluate the efficacy of an ornidazole-based sequential therapy for mites folliculitis treatment. Methods: Two-hundred patients with mites folliculitis were sequentially treated with either an ornidazole- or metronidazole-based regimen. Sebum cutaneum was extruded from the sebaceous glands of each patient's nose and the presence of Demodex mites were examined by light microscopy. The clinical manifestations of relapse of mites folliculitis were recorded and the subjects were followed up at 2, 4, 8, and 12 weeks post-treatment. Results: Patients treated with the ornidazole-based regimen showed an overall effective rate of 94.0%. Additionally, at the 2, 4, 8, and 12-week follow-up, these patients had significantly lower rates of Demodex mite relapse and new lesion occurrence compared with patients treated with the metronidazole-based regimen (P < 0.05). Conclusion: Sequential therapy using ornidazole, betamethasone, and recombinant bovine basic fibroblast growth factor (rbFGF) gel is highly effective for treating mites folliculitis. PMID:27399141

Clinical evaluation of the safety and efficacy of 10% imidacloprid + 2.5% moxidectin topical solution for the treatment of ear mite (Otodectes cynotis) infestations in dogs.

PubMed

Arther, R G; Davis, W L; Jacobsen, J A; Lewis, V A; Settje, T L

2015-05-30

A clinical field investigation was conducted to evaluate the safety and efficacy of 10% imidacloprid/2.5% moxidectin for the treatment of ear mites (Otodectes cynotis) in dogs. The study was a multi-centered, blinded, positive controlled, randomized clinical trial conducted under field conditions with privately owned pets. A total of 17 veterinary clinics enrolled cases for the study. An otoscopic examination was performed to confirm the presence of O. cynotis residing in the ear of the dog prior to enrollment. A single-dog household was enrolled in the study if the dog had 5 or more ear mites and an acceptable physical examination. A multi-dog household was eligible if at least one dog in the household had 5 or more mites and all dogs in the household had acceptable physical exams and met the inclusion criteria. Qualified households were randomly assigned to treatments to receive either 10% imidacloprid+2.5% moxidectin topical solution or topical selamectin solution (positive control product) according to a pre-designated enrollment ratio of 2:1, respectively. If more than one dog in a multiple dog household had adequate numbers of ear mites, one dog was randomly selected to represent the household for efficacy evaluation prior to treatment. Treatments were administered twice per label and dose banding directions for each product approximately 28 days apart (Days 0 and 28), by the dog's owner at the study site. All dogs in a household were treated on the same day and with the same product. The owners completed a post-treatment observation form one day after each treatment. Post-treatment otoscopic examinations were performed by the investigators or attending veterinarian on Days 28 and 56. Physical examinations were performed on Days 0 and 56. One hundred and four (104) households were evaluated for efficacy on SD 28, and 102 households were evaluated for efficacy on SD 56. The dogs' ages ranged from 2 months to 16 years. A total of 247 dogs were evaluated for safety. Percent efficacy was based on the percentage of dogs cleared of ear mites. Mite clearance on Day 28 was 71% for the imidacloprid+moxidectin group and 69% for the selamectin group. Mite clearance on Day 56 was 82% for the imidacloprid+moxidectin group and 74% for the selamectin group. No serious adverse events associated with either product were observed during the study. The study demonstrated that 10% imidacloprid+2.5% moxidectin applied using two topical treatments, 28 days apart, was safe and achieved similar efficacy against O. cynotis as selamectin treatments applied and evaluated under the same conditions. Copyright © 2015 Elsevier B.V. All rights reserved.

Biological activity of the mite Sancassania sp. (Acari: Acaridae) from bat guano associated with the pathogenic fungus Histoplasma capsulatum.

PubMed

Estrada-Bárcenas, Daniel A; Palacios-Vargas, José G; Estrada-Venegas, Edith; Klimov, Pavel B; Martínez-Mena, Alejandro; Taylor, Maria Lucia

2010-03-01

Mites and the mammal pathogenic fungus Histoplasma capsulatum are the major components of bat guano microbiota. Interactions between mites and H. capsulatum were evaluated under laboratory conditions. Acarid mites, mainly Sancassania sp., were the most abundant microarthropod in the sampled guano of the Mexican bat Tadarida brasiliensis mexicana and, based on its morphology, Sancassania sp. was similar to the cosmopolitan species Sancassania sphaerogaster. The mycophagous and vectoring activities of this mite were tested for H. capsulatum and two other fungal species, Sporothrix schenckii (pathogenic) and Aspergillus sclerotiorum (non-pathogenic). S. ca. sphaerogaster was able to reproduce in H. capsulatum and S. schenckii colonies, multiplying in great numbers under controlled fungal mycelial-phase culture conditions. H. capsulatum colonies were completely destroyed after 14 days of in vitro interaction with mites. In contrast, S. ca. sphaerogaster did not reproduce in A. sclerotiorum cultures. S. ca. sphaerogaster was found vectoring H. capsulatum, but not the two other fungal species studied.

Dust Mites Population in Indoor Houses of Suspected Allergic Patients of South Assam, India

PubMed Central

Sharma, Dhruba; Dutta, B. K.; Singh, A. B.

2011-01-01

Background. In the present study, quality and quantity of indoor dust mites was evaluated at the residence of 150 atopic allergic patients from four different districts of South Assam. Methods. Suspected patients with case history of allergic disease were selected for indoor survey. Dust samples (500 mg) were collected from the selected patient's house and were analyzed using standard methods. Results. About 60% of the selected patients were found suffering from respiratory disorders and rest 40% from skin allergy. The dominant mites recorded from indoor dust samples were Dermatophagoides followed by Blomia, Acarus, and Cheyletus while Caloglyphus was recorded in least number. The distribution of mites on the basis of housing pattern indicates that RCC type of buildings supports maximum dust mite's population followed by Assam type (semi-RCC) buildings, and the lowest count was observed in wooden houses. Environmental factors like temperature, rainfall, and relative humidity are found to determine the indoor mite's population. Severity of allergic attack in some of the typical cases was found to be proportional to the allergen load of mites in the dust samples. Conclusions. The economic status, housing pattern, and local environmental factors determine the diversity and abundance of dust mites in indoor environment. PMID:23724231

Mites associated with sugarcane crop and with native trees from adjacent Atlantic forest fragment in Brazil.

PubMed

Duarte, Mércia E; Navia, Denise; dos Santos, Lucas R; Rideiqui, Pedro J S; Silva, Edmilson S

2015-08-01

In some Brazilian regions the Atlantic forest biome is currently restrict to fragments occurring amid monocultures, as sugarcane crops in the Northeast region. Important influence of forest remnants over mite fauna of permanent crops have been showed, however it has been poorly explored on annual crops. The first step for understanding ecological relationship in an agricultural systems is known its composition. The objective of this study was to investigate the plant-inhabiting mite fauna associated with sugarcane crop (Saccharum officinarum L.) (Poaceae) and caboatã (Cupania oblongifolia Mart.) (Sapindaceae) trees in the state of Alagoas, Brazil. Sugarcane stalks and sugarcane and caboatã apical, middle and basal leaves were sampled. A total of 2565 mites were collected from sugarcane and classified into seven families of Trombidiformes and Mesostigmata orders, with most individuals belonging to the Eriophyidae, Tetranychidae and Tarsonemidae families. Among predatory mites, the Phytoseiidae were the most common. A total of 1878 mites were found on C. oblongifolia and classified into 13 families of Trombidiformes and Mesostigmata orders. The most abundant phytophagous mite family on caboatã was also Eriophyidae. In contrast to sugarcane, Ascidae was the most common predatory mite family observed in caboatã. No phytophagous species were common to both sugarcane and C. oblongifolia. However two predatory mites were shared between host plants. Although mites associated with only one native species in the forest fragment were evaluated in this study, our preliminary results suggest Atlantic forest native vegetation can present an important role in the sugarcane agricultural system as a source of natural enemies.

The acaricidal speed of kill of orally administered fluralaner against poultry red mites (Dermanyssus gallinae) on laying hens and its impact on mite reproduction.

PubMed

Brauneis, Maria D; Zoller, Hartmut; Williams, Heike; Zschiesche, Eva; Heckeroth, Anja R

2017-12-02

Dermanyssus gallinae, the poultry red mite, is a growing threat to chickens in poultry farms. This nocturnal hematophagous ectoparasite has a rapid rate of proliferation with a negative impact on the birds' health, welfare and productivity resulting in severe economic consequences for poultry farmers. A study was performed with fluralaner, a novel systemic ectoparasiticide, to evaluate its effect on mite vitality and reproduction after oral administration to laying hens. Sixteen healthy hens were randomly allocated to two study groups (n = 8). One group was orally treated with fluralaner by gavage at a dose of 0.5 mg/kg bodyweight twice 7 days apart. The negative control group received no treatment. Hens in each group were repeatedly infested with approximately 200 unfed adult D. gallinae at 1, 5, 8, 12, 15, 19, 22 and 26 days after the initial administration. After infestation and feeding for 2.5 h, 25 engorged mites per hen were collected and incubated in tubes. Mites were assessed for vitality (dead/live) at 4, 8, 12, and 24 h after each infestation. Tubes containing eggs and/or living mites were incubated another 8 days for assessment of mite reproductive capacity. Fluralaner demonstrated a fast speed of kill in mites within 4 h post-infestation for 12 days after treatment initiation. An efficacy (mite mortality) of 98.7-100% was achieved. At 15 days after treatment initiation, 100% efficacy was achieved within 24 h post-infestation, and no mite oviposition occurred during this period. Nineteen days after treatment initiation, the mites' ability to generate nymphs was reduced by 90.8%, which decreased to < 24.1% at later infestations. Fluralaner administered orally to hens twice, 7 days apart, provides efficacy against experimental poultry red mite infestation for at least 2 weeks. The demonstrated rapid speed of kill results in substantial depletion of the mites' oviposition and suggests that fluralaner can be an effective tool in the control of D. gallinae, one of the most urgent problems in poultry farms.

Mites associated with southern pine bark beetles in Allen Parish, Louisiana

Treesearch

John C. Moser; Lawrence M. Roton

1971-01-01

Ninety-six species of mites were associated with the southern pine beetle and allied scolytids in an outbreak area in Allen Parish, La. the complex was evaluated to ascertain which species may be of value as biological control agents.

Mites associated with Southern Pine Bark Beetles in Allen Parish, Louisiana

Treesearch

John C. Moser; Lawrence M. Roton

1971-01-01

Ninety-six species of mites were associated with the southern pine beetle and allied scolytides in an outbreak area in Allen Parish, LA. The complex was evaluated to ascertain which species may be of value as biological control agents.

Norwegian honey bees surviving Varroa destructor mite infestations by means of natural selection.

PubMed

Oddie, Melissa A Y; Dahle, Bjørn; Neumann, Peter

2017-01-01

Managed, feral and wild populations of European honey bee subspecies, Apis mellifera , are currently facing severe colony losses globally. There is consensus that the ectoparasitic mite Varroa destructor , that switched hosts from the Eastern honey bee Apis cerana to the Western honey bee A. mellifera , is a key factor driving these losses. For >20 years, breeding efforts have not produced European honey bee colonies that can survive infestations without the need for mite control. However, at least three populations of European honey bees have developed this ability by means of natural selection and have been surviving for >10 years without mite treatments. Reduced mite reproductive success has been suggested as a key factor explaining this natural survival. Here, we report a managed A. mellifera population in Norway, that has been naturally surviving consistent V. destructor infestations for >17 years. Surviving colonies and local susceptible controls were evaluated for mite infestation levels, mite reproductive success and two potential mechanisms explaining colony survival: grooming of adult worker bees and Varroa Sensitive Hygiene (VSH): adult workers specifically detecting and removing mite-infested brood. Mite infestation levels were significantly lower in surviving colonies and mite reproductive success was reduced by 30% when compared to the controls. No significant differences were found between surviving and control colonies for either grooming or VSH. Our data confirm that reduced mite reproductive success seems to be a key factor for natural survival of infested A. mellifera colonies. However, neither grooming nor VSH seem to explain colony survival. Instead, other behaviors of the adult bees seem to be sufficient to hinder mite reproductive success, because brood for this experiment was taken from susceptible donor colonies only. To mitigate the global impact of V. destructor , we suggest learning more from nature, i.e., identifying the obviously efficient mechanisms favored by natural selection.

Norwegian honey bees surviving Varroa destructor mite infestations by means of natural selection

PubMed Central

Dahle, Bjørn; Neumann, Peter

2017-01-01

Background Managed, feral and wild populations of European honey bee subspecies, Apis mellifera, are currently facing severe colony losses globally. There is consensus that the ectoparasitic mite Varroa destructor, that switched hosts from the Eastern honey bee Apis cerana to the Western honey bee A. mellifera, is a key factor driving these losses. For >20 years, breeding efforts have not produced European honey bee colonies that can survive infestations without the need for mite control. However, at least three populations of European honey bees have developed this ability by means of natural selection and have been surviving for >10 years without mite treatments. Reduced mite reproductive success has been suggested as a key factor explaining this natural survival. Here, we report a managed A. mellifera population in Norway, that has been naturally surviving consistent V. destructor infestations for >17 years. Methods Surviving colonies and local susceptible controls were evaluated for mite infestation levels, mite reproductive success and two potential mechanisms explaining colony survival: grooming of adult worker bees and Varroa Sensitive Hygiene (VSH): adult workers specifically detecting and removing mite-infested brood. Results Mite infestation levels were significantly lower in surviving colonies and mite reproductive success was reduced by 30% when compared to the controls. No significant differences were found between surviving and control colonies for either grooming or VSH. Discussion Our data confirm that reduced mite reproductive success seems to be a key factor for natural survival of infested A. mellifera colonies. However, neither grooming nor VSH seem to explain colony survival. Instead, other behaviors of the adult bees seem to be sufficient to hinder mite reproductive success, because brood for this experiment was taken from susceptible donor colonies only. To mitigate the global impact of V. destructor, we suggest learning more from nature, i.e., identifying the obviously efficient mechanisms favored by natural selection. PMID:29085753

Comparison of parasitic mite retrieval methods in a population of community cats.

PubMed

Milley, Catherine; Dryden, Michael; Rosenkrantz, Wayne; Griffin, Joya; Reeder, Christopher

2017-06-01

Objectives This study compared methods of mite retrieval from community cats in the Ohio River Valley region of the USA and determined incidence of parasitic mites in this region. Methods In total, 493 community cats were humanely trapped and anesthetized for a trap-neuter-return program. Cats received a dermatologic examination, ear swabs, superficial skin scraping, flea combing, acetate tape preparation and feces collection. All samples were examined microscopically. Large volumes of hair and scale from flea combing were dissolved in 10% potassium hydroxide and centrifuged with Sheather's solution. Fecal samples were mixed with Sheather's solution, filtered and centrifuged. Results Ear swabs were significantly ( P <0.05) better than other methods for finding chigger mites and Otodectes cynotis, and skin scraping was significantly better than ear swabs for finding Cheyletiella species. Only cats with O cynotis had clinical lesions. Mites remained identifiable for 6 months at room temperature. Mite incidence rates were as follows: Notoedres cati (1/493 cats), 0.002 (95% confidence interval [CI] 0-0.006); Lynxacarus radovskyi (2/493 cats), 0.004 (95% CI 0-0.01); Demodex gatoi (5/493 cats), 0.01 (95% CI 0.001-0.019); chigger mites (10/493 cats), 0.02 (95% CI 0.008-0.033); Cheyletiella species (12/493 cats), 0.024 (95% CI 0.011-0.038); and O cynotis (124/493 cats), 0.252 (95% CI 0.213-0.29). Conclusions and relevance Ear swabs are recommended when O cynotis or chigger mites are suspected. Skin scraping is more likely to yield positive results than ear swabs, but was not significantly better than acetate tape preparations, flea combing or fecal flotation for finding Cheyletiella species. Mites can remain identifiable for prolonged periods at room temperature. With the exception of O cynotis, the incidence of feline parasitic mites in the Ohio River Valley region of the USA is low; however, D gatoi and L radovskyi were present in the area and should be considered in cats with dermatologic disease attributable to them. In this population of community cats, asymptomatic carriage of mites was common.

Evaluation of impermeable covers for bedding in patients with allergic rhinitis.

PubMed

Terreehorst, Ingrid; Hak, Eelko; Oosting, Albert J; Tempels-Pavlica, Zana; de Monchy, Jan G R; Bruijnzeel-Koomen, Carla A F M; Aalberse, Rob C; Gerth van Wijk, Roy

2003-07-17

Encasing bedding in impermeable covers reduces exposure to house-dust mites, but the clinical benefit of this intervention as part of mite-avoidance measures for patients with allergic rhinitis is not known. We performed a multicenter, randomized, placebo-controlled trial of one year of use of impermeable bedding covers in the bedrooms of patients with rhinitis who were sensitized to house-dust mites to determine the effects on the signs and symptoms of disease. Three participating university medical centers enrolled 279 patients with allergic rhinitis who were randomly assigned to receive impermeable or non-impermeable (control) covers for their mattress, pillow, and duvet or blanket. At the start of the study, all participants received information on general allergen-avoidance measures. The severity of rhinitis was measured on a rhinitis-specific visual-analogue scale and by means of a daily symptom score and nasal allergen provocation testing. We also measured the concentrations of Dermatophagoides pteronyssinus (Der p1) and D. farinae (Der f1) in dust from patients' mattresses, bedroom floors, and living-room floors at base line and after 12 months as a measure of the efficacy of the intervention. A total of 232 patients completed the study. There was a significant reduction in Der p1 and Der f1 concentrations in the mattresses of the impermeable-cover group, whereas there was no significant reduction in the control group. However, there was no significant effect on the clinical outcome measures. Analyses of subgroups defined according to age, level of exposure, type and severity of sensitization, or characteristics of the patient's home had similar results. Mite-proof bedding covers, as part of a structured allergy-control program, reduced the level of exposure to mite allergens. Despite the success of the intervention, this single avoidance measure did not lead to a significant improvement of clinical symptoms in patients with allergic rhinitis. Copyright 2003 Massachusetts Medical Society

The Use of Tailored Testing with Instructional Programs.

DTIC Science & Technology

1986-03-01

AVAILABILITY OF REPORT Approved for public release: distribution un- t~X DWNCADNGSCHiEDULE li-mited. Reproduction in whole or in part is...of Education ,-’ Washington, DC 20V 0 Chicago, IL r06𔄁 Air Force Human Resources Lab Cdt. Arnold Bohrer . AFHRL/MPD Sectie Psychologisch Cnderzoek...University of Texas-Austin Univ-ir-tat Puss-ldorf Measurement and Evalu-,tion Er zi, gswi ssensch;ftl iches Cpnter Un ivf rsit ’tsst r. 1 Austin, TX 787

Morphometric variations of laelapine mite (Acari: Mesostigmata) populations infesting small mammals (Mammalia) in Brazil.

PubMed

Martins-Hatano, F; Gettinger, D; Manhães, M L; Bergallo, H G

2012-08-01

The goal of this study was to evaluate the morphometric variation of laelapine populations (Acari, Mesostigmata) associated with neotropical oryzomyine rodents at different geographic localities in Brazil. Three nominal mite species were selected for study, all infesting the pelage of small mammals at different localities in Rio de Janeiro, Espírito Santo, Bahia, and the Federal District, Brazil. To analyse morphometric characteristics, thirty-seven morphological characters distributed across the whole body of each specimen were measured. We use the Analysis of Principal Components, extracting the three first axes and projecting each mite in these axes. Major species level changes in the taxonomy of the host mammals allows an independent examination of morphometric variation of mites infesting a set of distinctly different host species at different geographic localities. Gigantolaelaps vitzthumi and Laelaps differens are associated with oryzomyine rodents of the genus Cerradomys, and consistently showed a tendency to cluster by host phylogeny. Laelaps manguinhosi associated with Nectomys rattus in central Brazil is morphometrically distinct from mites infesting N. squamipes in the coastal restingas of Rio de Janeiro and Espírito Santo. The results obtained here indicate that laelapine mite populations can vary among geographic areas and among phylogenetically related host species. Clearly, the study of these mites at the population level can be an important tool for clarifying the taxonomy of both mites and hosts.

Influence of heat and vibration on the movement of the northern fowl mite (Acari: Macronyssidae).

PubMed

Owen, Jeb P; Mullens, Bradley A

2004-09-01

Heat and vibration are common host-generated cues that ectoparasites use to orient to hosts. Three experiments evaluated effects of heat and vibration on the movement of northern fowl mite, Ornithonyssus sylviarum (Canestrini & Fanzago). Individual arrested mites in an isolation chamber always initiated movement (walking) after substrate vibration (7.8-min walking duration), but only initiated movement 50% of the time (2.8-min walking duration) upon exposure to a 3 degrees C heat fluctuation. Heat fluctuation in combination with vibration extended the period of activity by approximately 50% (11.6-min walking duration) compared with activity initiated by vibration alone. Mites with longer time off-host moved for shorter durations. In a choice test, individual mites consistently moved closer to a 35 degrees C heat source 1 or 6 mm away, but not to a heat source 11 mm away. In a circular arena, mites were able to orient accurately to a 35 degrees C heat source and reached the arena edge almost 4 times faster (11.2 s) than mites without a heat source (41.2 s). These results suggest that northern fowl mite is capable of directed thermo-orientation, as well as modulation of activity depending on the type of sensory information perceived. The adaptive significance of this orientation for a "permanent" ectoparasite is discussed.

Biology and control of Varroa destructor.

PubMed

Rosenkranz, Peter; Aumeier, Pia; Ziegelmann, Bettina

2010-01-01

The ectoparasitic honey bee mite Varroa destructor was originally confined to the Eastern honey bee Apis cerana. After a shift to the new host Apis mellifera during the first half of the last century, the parasite dispersed world wide and is currently considered the major threat for apiculture. The damage caused by Varroosis is thought to be a crucial driver for the periodical colony losses in Europe and the USA and regular Varroa treatments are essential in these countries. Therefore, Varroa research not only deals with a fascinating host-parasite relationship but also has a responsibility to find sustainable solutions for the beekeeping. This review provides a survey of the current knowledge in the main fields of Varroa research including the biology of the mite, damage to the host, host tolerance, tolerance breeding and Varroa treatment. We first present a general view on the functional morphology and on the biology of the Varroa mite with special emphasis on host-parasite interactions during reproduction of the female mite. The pathology section describes host damage at the individual and colony level including the problem of transmission of secondary infections by the mite. Knowledge of both the biology and the pathology of Varroa mites is essential for understanding possible tolerance mechanisms in the honey bee host. We comment on the few examples of natural tolerance in A. mellifera and evaluate recent approaches to the selection of Varroa tolerant honey bees. Finally, an extensive listing and critical evaluation of chemical and biological methods of Varroa treatments is given. This compilation of present-day knowledge on Varroa honey bee interactions emphasizes that we are still far from a solution for Varroa infestation and that, therefore, further research on mite biology, tolerance breeding, and Varroa treatment is urgently needed. Copyright 2009 Elsevier Inc. All rights reserved.

Monitoring of Dermanyssus gallinae in free-range poultry farms.

PubMed

Zenner, L; Bon, G; Chauve, C; Nemoz, C; Lubac, S

2009-06-01

Various methods for monitoring Dermanyssus gallinae infestations within free-range egg production units were compared. The study was carried out in five egg-producing free-range poultry buildings infested with D. gallinae. Each farm was divided into six zones (each zone including nest boxes, perches and duckboard) for placing two types of traps (corrugated cardboard and thick card traps) or examining dried droppings for presence of mites. Traps were removed 24 h later, placed into bags and mites were counted at the laboratory using binocular magnification. Droppings were also inspected by eye and mite numbers were estimated. All the methods used allowed us to detect mites although their efficacy differed. The number of mites collected was independent of the type of trap used. Examination of the droppings did not differentiate between buildings with differing mite populations. Placing traps in the nest boxes is a less reliable indicator than placing them on the perches. It appears that the most coherent method for evaluating the D. gallinae population within a free-range flock is to place thick card traps throughout the building, on perches favoured by birds.

Effect of permethrin impregnated plastic strips on Dermanyssus gallinae in loose-housing systems for laying hens.

PubMed

Nordenfors, H; Höglund, J; Tauson, R; Chirico, J

2001-12-03

The effect of permethrin impregnated plastic strips (Die No Mite Strips) was evaluated on Dermanyssus gallinae populations in aviary systems for layers in Sweden. Two application strategies of the strips were tested: (A) attached in the housing system, allowing the birds to rub against the strips and thereby get the acaricide released onto their plumage, and (B) attached out of reach of the hens, at two different sites (perches and egg-belt lids) of the inner surfaces of the system, where the mites sheltered during the day. On two farms with 2030 (A) and 3384 (B) hens, and existing mite populations, strips were mounted for 20 and 10 weeks, respectively, and mite numbers were monitored by traps. With application A an overall mite reduction of 53% was observed, while with B the mean mite numbers decreased by 39% at the perches and 92% at the egg-belt lid. The strips were originally designed for caged hens afflicted by ectoparasites that stay on the host for most of their life cycle. However, since D. gallinae spends most of its time off the host, it was not possible to control the parasite with application A. Resistance tests performed on mites from both treated and control compartments where application A was used showed no indication of resistance to permethrin, while 95% of the mites survived a 48 h exposure to the compound where application B was performed. Thus, permethrin resistant mites appeared to be the main reason for the failure to control D. gallinae with application B.

Characterization of spatial distribution of Tetranychus urticae in peppermint in California and implication for improving sampling plan.

PubMed

Rijal, Jhalendra P; Wilson, Rob; Godfrey, Larry D

2016-02-01

Twospotted spider mite, Tetranychus urticae Koch, is an important pest of peppermint in California, USA. Spider mite feeding on peppermint leaves causes physiological changes in the plant, which coupling with the favorable environmental condition can lead to increased mite infestations. Significant yield loss can occur in absence of pest monitoring and timely management. Understating the within-field spatial distribution of T. urticae is critical for the development of reliable sampling plan. The study reported here aims to characterize the spatial distribution of mite infestation in four commercial peppermint fields in northern California using spatial techniques, variogram and Spatial Analysis by Distance IndicEs (SADIE). Variogram analysis revealed that there was a strong evidence for spatially dependent (aggregated) mite population in 13 of 17 sampling dates and the physical distance of the aggregation reached maximum to 7 m in peppermint fields. Using SADIE, 11 of 17 sampling dates showed aggregated distribution pattern of mite infestation. Combining results from variogram and SADIE analysis, the spatial aggregation of T. urticae was evident in all four fields for all 17 sampling dates evaluated. Comparing spatial association using SADIE, ca. 62% of the total sampling pairs showed a positive association of mite spatial distribution patterns between two consecutive sampling dates, which indicates a strong spatial and temporal stability of mite infestation in peppermint fields. These results are discussed in relation to behavior of spider mite distribution within field, and its implications for improving sampling guidelines that are essential for effective pest monitoring and management.

Efficacy of a novel formulation of metaflumizone plus amitraz for the treatment of sarcoptic mange in dogs.

PubMed

Fourie, L J; Kok, D J; du Plessis, A; Rugg, D

2007-12-15

A novel spot-on formulation containing metaflumizone plus amitraz (ProMeris/ProMeris Duo for Dogs, Fort Dodge Animal Health, Overland Park, KS) was evaluated for efficacy against sarcoptic mange mites in naturally infested dogs. Sixteen dogs were allocated to two equal groups and were housed individually. Eight of the dogs were treated topically with metaflumizone plus amitraz at the proposed minimum dose rate (20mg/kg of each of metaflumizone and amitraz, at a dose volume of 0.133ml/kg) on Days 0 and 28. The other eight were treated with metaflumizone plus amitraz at the proposed minimum dose rate on Days 0, 14, 28 and 42. To enumerate Sarcoptes scabiei mites, skin scrapings were taken on each of Days 2, 14, 28, 42 and 56. Clinical signs of mange and the extent of sarcoptic lesions were evaluated on each dog when scrapings were made. Evaluation of the efficacy of the treatment was based on the absence of mites supported by the absence of clinical signs associated with canine sarcoptic mange. Treatment with metaflumizone plus amitraz at the minimum proposed dose rate at monthly (two treatments) or two-weekly (four treatments) intervals resulted in a rapid reduction of mites and improved clinical signs. The overall cure rates at Day 56, based on zero mite counts and/or resolution of clinical signs were 75% and 83% of dogs for the monthly and two-weekly regimens, respectively.

Effects of azadirachtin on Tetranychus urticae (Acari: Tetranychidae) and its compatibility with predatory mites (Acari: Phytoseiidae) on strawberry.

PubMed

Bernardi, Daniel; Botton, Marcos; da Cunha, Uemerson Silva; Bernardi, Oderlei; Malausa, Thibaut; Garcia, Mauro Silveira; Nava, Dori Edson

2013-01-01

The spider mite, Tetranychus urticae, is the major strawberry pest in Brazil. The main strategies for its control comprise synthetic acaricides and predatory mites. The recent register of a commercial formula of azadirachtin (Azamax(®) 12 g L(-1) ) can be viable for control of T. urticae. In this work, the effects of azadirachtin on T. urticae and its compatibility with predatory mites Neoseiulus californicus and Phytoseiulus macropilis in the strawberry crop were evaluated. Azadirachtin was efficient against T. urticae, with a mortality rate similar to that of abamectin. In addition, the azadirachtin showed lower biological persistence (7 days) than abamectin (21 days). Azadirachtin did not cause significant mortality of adult predatory mites (N. californicus and P. macropilis), but it did reduce fecundity by 50%. However, egg viability of the azadirachtin treatments was similar to that of the control (>80% viability). The use of azadirachtin and predatory mites is a valuable tool for controlling T. urticae in strawberry crop. Azadirachtin provided effective control of T. urticae and is compatible with the predatory mites N. californicus and P. macropilis. It is an excellent tool to be incorporated into integrated pest management for strawberry crop in Brazil. Copyright © 2012 Society of Chemical Industry.

Citrus leprosis virus C Infection Results in Hypersensitive-Like Response, Suppression of the JA/ET Plant Defense Pathway and Promotion of the Colonization of Its Mite Vector

PubMed Central

Arena, Gabriella D.; Ramos-González, Pedro L.; Nunes, Maria A.; Ribeiro-Alves, Marcelo; Camargo, Luis E. A.; Kitajima, Elliot W.; Machado, Marcos A.; Freitas-Astúa, Juliana

2016-01-01

Leprosis is a serious disease of citrus caused by Citrus leprosis virus C (CiLV-C, genus Cilevirus) whose transmission is mediated by false spider mites of the genus Brevipalpus. CiLV-C infection does not systemically spread in any of its known host plants, thus remaining restricted to local lesions around the feeding sites of viruliferous mites. To get insight into this unusual pathosystem, we evaluated the expression profiles of genes involved in defense mechanisms of Arabidopsis thaliana and Citrus sinensis upon infestation with non-viruliferous and viruliferous mites by using reverse-transcription qPCR. These results were analyzed together with the production of reactive oxygen species (ROS) and the appearance of dead cells as assessed by histochemical assays. After interaction with non-viruliferous mites, plants locally accumulated ROS and triggered the salicylic acid (SA) and jasmonate/ethylene (JA/ET) pathways. ERF branch of the JA/ET pathways was highly activated. In contrast, JA pathway genes were markedly suppressed upon the CiLV-C infection mediated by viruliferous mites. Viral infection also intensified the ROS burst and cell death, and enhanced the expression of genes involved in the RNA silencing mechanism and SA pathway. After 13 days of infestation of two sets of Arabidopsis plants with non-viruliferous and viruliferous mites, the number of mites in the CiLV-C infected Arabidopsis plants was significantly higher than in those infested with the non-viruliferous ones. Oviposition of the viruliferous mites occurred preferentially in the CiLV-C infected leaves. Based on these results, we postulated the first model of plant/Brevipalpus mite/cilevirus interaction in which cells surrounding the feeding sites of viruliferous mites typify the outcome of a hypersensitive-like response, whereas viral infection induces changes in the behavior of its vector. PMID:27933078

Morphometric variation in Periglischrus torrealbai (Acari: Spinturnicidae) on three species of host bats (Chiroptera: Phyllostomidae) with a new record of host species.

PubMed

de Almeida, Juliana Cardoso; Gomes, Luiz Antonio Costa; Owen, Robert D

2018-01-01

We evaluated morphometric variation of the mite Periglischrus torrealbai (Spinturnicidae) on three species of host bats: Phyllostomus discolor, P. hastatus, and Tonatia bidens (Phyllostomidae). A total of 67 females and 74 males of P. torrealbai were collected from 41 host individuals of these three bat species that were sampled in Brazil, Paraguay, and Peru. Twenty-one measurements from the dorsal side and 28 from the ventral side were recorded from female mites and 21 dorsal and 34 ventral measurements were taken from males. To evaluate morphological variation of P. torrealbai on different species of host bats, principal component analysis and unweighted pair-group method using arithmetic averages cluster analysis with Euclidean distances were used. Both analyses showed three groups of mites clearly separated: group 1 comprised all ectoparasites collected from T. bidens, group 2 included all mites from P. hastatus, and group 3 had all those from P. discolor. This result indicates that P. torrealbai varies morphologically by host bat species and suggests that this nominal species comprises three morphologically distinct species. In the present study, we record for the first time, the association between P. torrealbai and T. bidens. Our data reinforce the high relationship of specificity between Periglischrus mites and phyllostomid bat species.

Incidense of spider mites in South Texas cotton fields

USDA-ARS?s Scientific Manuscript database

The incidence of spider mites was evaluated· in four locations of south Texas between Progreso (Hidalgo Co.) to Bishop (Nueces Co.). This is an area with a south to north transect of 125 miles from south Progreso to north Bishop (respectively).The other two intermediate sampled locations were Harlin...

Dust Allergens within Rural Northern Rocky Mountain Residences.

PubMed

Weiler, Emily; Semmens, Erin; Noonan, Curtis; Cady, Carol; Ward, Tony

2015-01-23

To date, few studies have characterized allergens within residences located in rural areas of the northern Rocky Mountain region. In this study, we collected dust samples from 57 homes located throughout western Montana and northern Idaho. Dust samples were collected and later analyzed for dust mite allergens Der f 1 and Der p 1 , Group 2 mite allergens ( Der p 2 and Der f 2 ), domestic feline ( Fel d 1 ), and canine ( Can f 1 ). Indoor temperature and humidity levels were also measured during the sampling program, as were basic characteristics of each home. Dog (96%) and cat (82%) allergens were the most prevalent allergens found in these homes (even when a feline or canine did not reside in the home). Results also revealed the presence of dust mites. Seven percent (7%) of homes tested positive for Der p 1 , 19% of homes were positive for Der f 1 , and 5% of homes were positive for the Group 2 mite allergens. Indoor relative humidity averaged 27.0 ± 7.6% within the homes. Overall, humidity was not significantly associated with dust mite presence, nor was any of the other measured home characteristics. This study provides a descriptive assessment of indoor allergen presence (including dust mites) in rural areas of the northern Rocky Mountains, and provides new information to assist regional patients with reducing allergen exposure using in-home intervention strategies.

Use of Selamectin and Moxidectin in the Treatment of Mouse Fur Mites

PubMed Central

Mook, Deborah M; Benjamin, Kimberly A

2008-01-01

A breeding colony consisting of 250 different strains of mice was treated with the topical acaricide selamectin for the mouse fur mite Myocoptes musculinus, with no apparent ill effect, suggesting that this drug is safe for use in mice. To further evaluate their efficacy in treating Myocoptes spp., we compared selamectin with another acaricide, moxidectin, in a controlled manner. Infested mice were treated with selamectin or moxidectin at the time of cage change, and a subset of mice was retreated 10 d later. Mice underwent routine cellophane tape examination of the pelage for 1 y. Although no adult mites were found in any group at 1 mo after treatment, egg casings were found in the selamectin treatment group as late as 6 mo after treatment, prompting concern about its effectiveness. Moxidectin used in combination with cage changing was effective in eradicating mites, with mice negative for traces of mites on cellophane tape examination of the pelage from months 2 through 12 after treatment. PMID:18459708

Evaluation of predation of the mite Lasioseius penicilliger (Aracnida: Mesostigmata) on Haemonchus contortus and bacteria-feeding nematodes.

PubMed

Aguilar-Marcelino, L; Quintero-Martínez, M T; Mendoza de Gives, P; López-Arellano, M E; Liébano-Hernández, E; Torres-Hernández, G; González-Camacho, J M; Cid del Prado, I

2014-03-01

Predation by the mite Lasioseius penicilliger was studied on three nematode species, i.e. infective larval stages (L3) of Haemonchus contortus and adults of Panagrellus redivivus and Rhabditis sp. Experiments were carried out in 5.5-cm diameter Petri dishes containing 2% water-agar over a period of 5 days. Batches of up to 1500 third-stage larvae (L3) of H. contortus and 1000 adult nematodes of P. redivivus and Rhabditis sp. were exposed to five mites in separate Petri dishes. Upon contact, each mite used its pedipalp and legs to identify and hold its prey and then used its chelicerae to feed upon the prey. Predation by L. penicilliger was chance dependent but mites became aggregated around any injured/damaged prey, thereby suggesting some form of chemoperception. The rate of predation on the three species of nematodes was high but L3 of H. contortus and adult Rhabditis sp. were preferred.

The residual and direct effects of reduced-risk and conventional miticides on twospotted spider mites, Tetranychus urticae (Acari: Tetranychidae) and predatory mites (Acari: Phytoseiidae)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liburd, O.E.; White, J.C.; Rhodes, E.M.

2007-03-15

The residual effects of several reduced-risk and conventional miticides were evaluated in strawberries (Fragaria z ananassa Duchesne) on the twospotted spider mite (TSSM), Tetranychus urticae Koch (Acari: Tetranychidae) and on 2 predatory mites, Neoseiulus californicus McGregor and Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae). Experiments were conducted in the laboratory and greenhouse. The greenhouse experiments also tested the direct effects of the miticides on TSSM. The efficacy of conventional and reduced-risk miticides was evaluated on strawberry leaf discs and on whole plants for control of TSSM. Furthermore, the residual effects of these miticides were evaluated on whole strawberry plants against selective predatorymore » mites. For TSSM, 5 treatments were evaluated: a conventional miticide; fenbutatin-oxide (Vendex[reg]) and 3 reduced-risk miticides; binfenazate (Acramite 50WP[reg]), activated garlic extract (Repel[reg]), sesame seed and castor oil (Wipeout[reg]), and a water-treated control. For predatory mites, the residual effects of only Acramite[reg] and Vendex[reg] were evaluated. Acramite[reg] was the most effective acaricide in reducing TSSM populations in both the laboratory and greenhouse experiments. Vendex[reg] and Wipeout[reg] were also effective in the laboratory, but did not cause significant reduction of TSSM in the greenhouse. Repel[reg] was the least effective of the 4 pesticides evaluated. Neither Acramite[reg] nor Vendex[reg] had a significant effect on either predatory mite species. However, there appeared to be more predatory mites on the Vendex[reg]-treated plants than on the Acramite[reg]-treated plants. There were significantly more predatory mites of both species on the cue plants, which were inoculated with TSSM versus the non-cue plants, which were not inoculated. (author) [Spanish] Los efectos residuales en poblaciones de la 'arana roja', Tetranychus urticae Koch (Acari: Tetranichidae) y de los acaros predadores Neoseiulus californicus McGregor y Phytoseilus persimilis Athias-Henriot (Acari: Phytoseiidae) causados por varios acaricidas convencionales y de riesgo-reducido fueron evaluados en fresas (Fragaria x ananassa Duchense). Los experimentos fueron realizados en laboratorio e invernadero. Los experimentos en el invernadero evaluaron tambien el efecto directo de los acaricidas en la 'arana roja'. La eficacia para controlar la 'arana roja' de los acaricidas convencionales y de riesgo-reducido fue evaluada en discos de las hojas y en plantas de fresa, y los efectos residuales de los acaricidas en los acaros predadores fueron evaluados en plantas completas. Para la 'arana roja' se evaluaron cinco tratamientos: el acaricida convencional fenbutatin-oxido (Vendex[reg]), 3 acaricidas de riesgo-reducido binfenazate (Acaramite 50WP[reg]), extracto de ajo activado (Repel[reg]), aceite de semillas de ajonjoli y ricino (Wipeout[reg]) y un control tratado con agua. Para los acaros predadores solamente los efectos de Acaramite[reg] y Vendex[reg] fueron evaluados. Acaramite[reg] fue el tratamiento mas efectivo para la 'arana roja' en el laboratorio y el invernadero. Vendex[reg] y Wipeout[reg] fueron tambien efectivos en el laboratorio, pero no causaron una reduccion significativa de 'aranas rojas' en el invernadero. Repel[reg] fue el tratamiento evaluado menos eficaz. Ni Acaramite[reg] ni Vendex[reg] redujeron significativamente las poblaciones de acaros predadores. Sin embargo, aparentemente hay mas acaros predadores en Vendex[reg] que en Acaramite[reg]. Tambien se encontraron significativamente mas acaros predadores en plantas inoculadas que en plantas no inoculadas. (author)« less

Better detection of Demodex mites by Löffler's alkaline methylene blue staining in patients with blepharitis.

PubMed

Kiuchi, Katsuji

2018-01-01

To determine whether the Löffler's alkaline methylene blue staining method is better than no staining in detecting Demodex mites in the eyelashes of patients with blepharitis. Eyelashes were collected from 22 patients with blepharitis. The mean age of the patients was 82.5±6.2 years (± SD) with a range from 71 to 93 years. Eyelashes were epilated by forceps and placed individually on microscope slides. The number of Demodex mites was determined by conventional optical microscopy before and immediately after the addition of the methylene blue staining solution. The mean Demodex count before the addition of the methylene blue solution was 2.9±2.9, and it was 4.4±3.9 after the addition of the methylene blue solution ( P <0.01, Wilcoxon test). The methylene blue staining method is a simple and useful method in detecting the presence and quantifying the number of Demodex mites. We recommend the methylene blue staining method not only for the diagnosis of the presence of Demodex mites but also to evaluate the therapeutic effects of medications to eliminate the mite infestation.

Better detection of Demodex mites by Löffler’s alkaline methylene blue staining in patients with blepharitis

PubMed Central

Kiuchi, Katsuji

2018-01-01

Purpose To determine whether the Löffler’s alkaline methylene blue staining method is better than no staining in detecting Demodex mites in the eyelashes of patients with blepharitis. Materials and methods Eyelashes were collected from 22 patients with blepharitis. The mean age of the patients was 82.5±6.2 years (± SD) with a range from 71 to 93 years. Eyelashes were epilated by forceps and placed individually on microscope slides. The number of Demodex mites was determined by conventional optical microscopy before and immediately after the addition of the methylene blue staining solution. Results The mean Demodex count before the addition of the methylene blue solution was 2.9±2.9, and it was 4.4±3.9 after the addition of the methylene blue solution (P<0.01, Wilcoxon test). Conclusion The methylene blue staining method is a simple and useful method in detecting the presence and quantifying the number of Demodex mites. We recommend the methylene blue staining method not only for the diagnosis of the presence of Demodex mites but also to evaluate the therapeutic effects of medications to eliminate the mite infestation. PMID:29713140

Spider mite infestations reduce Bacillus thuringiensis toxin concentration in corn leaves and predators avoid spider mites that have fed on Bacillus thuringiensis corn

USDA-ARS?s Scientific Manuscript database

Transgenic crops containing pyramid-stacked genes for Bacillus thuringiensis derived toxins for controlling coleopteran and lepidopteran pests are increasingly common. As part of environmental risk assessments, these crops are evaluated for toxicity against non-target organisms, and for their poten...

Cross Reference Index for Bioenvironmental Engineer and Military Public Health Offices

DTIC Science & Technology

1992-03-01

Food Recall AFR 161-42 DOD Hazardous Food and Nonprescription Drug Recall System Insects and Mite Pests in Food AGR-HB-655 Insects and Mite Pests in Food...Solution, 11 Hazard Communication, 12 Hazardous Energy Control, 21, 22 Hazardous Food Recall Program, 9 Hazardous Waste, 11, 26 Hazardous Materials...34Institutional Meat Purchase Specification" NAMPS "National Association of Meat Purveyor’s" DPSC Support DOD 4155.6 Subsistence Inspection Manual Hazardous

Persistence of subclinical deformed wing virus infections in honeybees following Varroa mite removal and a bee population turnover

PubMed Central

Semberg, Emilia; Forsgren, Eva; de Miranda, Joachim R.

2017-01-01

Deformed wing virus (DWV) is a lethal virus of honeybees (Apis mellifera) implicated in elevated colony mortality rates worldwide and facilitated through vector transmission by the ectoparasitic mite Varroa destructor. Clinical, symptomatic DWV infections are almost exclusively associated with high virus titres during pupal development, usually acquired through feeding by Varroa mites when reproducing on bee pupae. Control of the mite population, generally through acaricide treatment, is essential for breaking the DWV epidemic and minimizing colony losses. In this study, we evaluated the effectiveness of remedial mite control on clearing DWV from a colony. DWV titres in adult bees and pupae were monitored at 2 week intervals through summer and autumn in acaricide-treated and untreated colonies. The DWV titres in Apistan treated colonies was reduced 1000-fold relative to untreated colonies, which coincided with both the removal of mites and also a turnover of the bee population in the colony. This adult bee population turnover is probably more critical than previously realized for effective clearing of DWV infections. After this initial reduction, subclinical DWV titres persisted and even increased again gradually during autumn, demonstrating that alternative non-Varroa transmission routes can maintain the DWV titres at significant subclinical levels even after mite removal. The implications of these results for practical recommendations to mitigate deleterious subclinical DWV infections and improving honeybee health management are discussed. PMID:28686725

House dust and storage mite contamination of dry dog food stored in open bags and sealed boxes in 10 domestic households.

PubMed

Gill, Christina; McEwan, Neil; McGarry, John; Nuttall, Tim

2011-04-01

Dry pet food is a potential source of exposure to house dust and storage mite allergens in canine atopic dermatitis. This study evaluated contamination of house dust and dry dog food stored in paper bags, sealable plastic bags and sealable plastic boxes in 10 households for 90 days using Acarex(®) tests for guanine, a Der p 1 ELISA and mite flotation. Acarex(®) tests were negative in all the food samples but positive in all the house dust samples. The Der p 1 levels and mite numbers significantly increased in food from paper bags (P = 0.0073 and P = 0.02, respectively), but not plastic bags or boxes. Mite numbers and Der p 1 levels were 10-1000 times higher in house dust than the corresponding food samples (P < 0.0001). There were significant correlations between Der p 1 in house dust and food from the paper (P < 0.0001) and plastic bags (P = 0.003), and mite numbers in house dust and food from the paper bags (P = 0.0007). Bedding and carpets were significantly associated with Der p 1 levels in house dust (P = 0.015 and P = 0.01, respectively), and food from the paper (both P = 0.02) and plastic bags (P = 0.03 and P = 0.04, respectively). Mites were identified in six of 10 paper bag, three of 10 plastic bag, one of 10 plastic box and nine of 10 house dust samples. These comprised Dermatophagoides (54%), Tyrophagus (10%; all from food) and unidentified mites (36%). Storage of food in sealable plastic boxes largely prevented contamination for 3 months. Exposure to mites and mite proteins in all the stored food, however, appeared to be trivial compared with house dust. © 2010 The Authors. Journal compilation © 2010 ESVD and ACVD.

Clinical and immunological responses of dust mite sensitive, atopic dogs to treatment with sublingual immunotherapy (SLIT).

PubMed

DeBoer, Douglas J; Verbrugge, Maria; Morris, Mary

2016-04-01

Sublingual immunotherapy (SLIT) has been reported to be beneficial in people with atopic dermatitis (AD) and dust mite sensitivity. Evaluation of this therapy has not been reported in spontaneous canine AD. The objective of this study was to preliminarily evaluate the effectiveness of an established SLIT protocol, as used in human patients, in dogs with AD. Ten dust mite sensitive dogs with spontaneous AD. Dogs underwent a 6 month open trial of SLIT concurrently with decreasing dose oral methylprednisolone. Clinical evaluations and quantitative serum anti-mite IgE and IgG levels were performed every 2 months. Mean methylprednisolone use from the first 2 months of the study to the final 2 months declined from 10.2 to 4.3 mg/kg/2 months (P < 0.001, Student's paired t-test); at 6 months, four dogs required no oral corticosteroid administration. Over the course of the study, median Canine Atopic Dermatitis Extent and Severity Index (CADESI)-03 scores declined from 76.5 to 59; median pruritus scores declined from 65 to 37 (P < 0.02 and P < 0.01, respectively; Wilcoxon signed-rank test). Pre- and post-SLIT intradermal test scores for mite allergen were not significantly different over time. Median Dermatophagoides farinae (DF)-specific IgE levels declined significantly from 150.2 × 10(3) AU/mL to 3.6 × 10(3) AU/mL (P < 0.05). Concurrently, median DF-specific IgG levels increased from 18.5 × 10(6) AU/mL to 3923.4 × 10(6) AU/mL (P < 0.05; Wilcoxon signed-rank tests). SLIT treatment produced clinical improvement in dogs with dust mite-associated AD and was associated with serological changes supporting this improvement. Further studies in larger numbers of dogs and those with polysensitization are warranted. © 2016 ESVD and ACVD.

Feces Derived Allergens of Tyrophagus putrescentiae Reared on Dried Dog Food and Evidence of the Strong Nutritional Interaction between the Mite and Bacillus cereus Producing Protease Bacillolysins and Exo-chitinases

PubMed Central

Erban, Tomas; Rybanska, Dagmar; Harant, Karel; Hortova, Bronislava; Hubert, Jan

2016-01-01

Tyrophagus putrescentiae (Schrank, 1781) is an emerging source of allergens in stored products and homes. Feces proteases are the major allergens of astigmatid mites (Acari: Acaridida). In addition, the mites are carriers of microorganisms and microbial adjuvant compounds that stimulate innate signaling pathways. We sought to analyze the mite feces proteome, proteolytic activities, and mite-bacterial interaction in dry dog food (DDF). Proteomic methods comprising enzymatic and zymographic analysis of proteases and 2D-E-MS/MS were performed. The highest protease activity was assigned to trypsin-like proteases; lower activity was assigned to chymotrypsin-like proteases, and the cysteine protease cathepsin B-like had very low activity. The 2D-E-MS/MS proteomic analysis identified mite trypsin allergen Tyr p3, fatty acid-binding protein Tyr p13 and putative mite allergens ferritin (Grp 30) and (poly)ubiquitins. Tyr p3 was detected at different positions of the 2D-E. It indicates presence of zymogen at basic pI, and mature-enzyme form and enzyme fragment at acidic pI. Bacillolysins (neutral and alkaline proteases) of Bacillus cereus symbiont can contribute to the protease activity of the mite extract. The bacterial exo-chitinases likely contribute to degradation of mite exuviae, mite bodies or food boluses consisting of chitin, including the peritrophic membrane. Thus, the chitinases disrupt the feces and facilitate release of the allergens. B. cereus was isolated and identified based on amplification and sequencing of 16S rRNA and motB genes. B. cereus was added into high-fat, high-protein (DDF) and low-fat, low-protein (flour) diets to 1 and 5% (w/w), and the diets palatability was evaluated in 21-day population growth test. The supplementation of diet with B. cereus significantly suppressed population growth and the suppressive effect was higher in the high-fat, high-protein diet than in the low-fat, low-protein food. Thus, B. cereus has to coexist with the mite in balance to be beneficial for the mite. The mite-B. cereus symbiosis can be beneficial-suppressive at some level. The results increase the veterinary and medical importance of the allergens detected in feces. The B. cereus enzymes/toxins are important components of mite allergens. The strong symbiotic association of T. putrescentiae with B. cereus in DDF was indicated. PMID:26941650

Genome-wide interaction study of dust mite allergen on lung function in children with asthma.

PubMed

Forno, Erick; Sordillo, Joanne; Brehm, John; Chen, Wei; Benos, Takis; Yan, Qi; Avila, Lydiana; Soto-Quirós, Manuel; Cloutier, Michelle M; Colón-Semidey, Angel; Alvarez, Maria; Acosta-Pérez, Edna; Weiss, Scott T; Litonjua, Augusto A; Canino, Glorisa; Celedón, Juan C

2017-10-01

Childhood asthma is likely the result of gene-by-environment (G × E) interactions. Dust mite is a known risk factor for asthma morbidity. Yet, there have been no genome-wide G × E studies of dust mite allergen on asthma-related phenotypes. We sought to identify genetic variants whose effects on lung function in children with asthma are modified by the level of dust mite allergen exposure. A genome-wide interaction analysis of dust mite allergen level and lung function was performed in a cohort of Puerto Rican children with asthma (Puerto Rico Genetics of Asthma and Lifestyle [PRGOAL]). Replication was attempted in 2 independent cohorts, the Childhood Asthma Management Program (CAMP) and the Genetics of Asthma in Costa Rica Study. Single nucleotide polymorphism (SNP) rs117902240 showed a significant interaction effect on FEV 1 with dust mite allergen level in PRGOAL (interaction P = 3.1 × 10 -8 ), and replicated in the same direction in CAMP white children and CAMP Hispanic children (combined interaction P = .0065 for replication cohorts and 7.4 × 10 -9 for all cohorts). Rs117902240 was positively associated with FEV 1 in children exposed to low dust mite allergen levels, but negatively associated with FEV 1 in children exposed to high levels. This SNP is on chromosome 8q24, adjacent to a binding site for CCAAT/enhancer-binding protein beta, a transcription factor that forms part of the IL-17 signaling pathway. None of the SNPs identified for FEV 1 /forced vital capacity replicated in the independent cohorts. Dust mite allergen exposure modifies the estimated effect of rs117902240 on FEV 1 in children with asthma. Analysis of existing data suggests that this SNP may have transcription factor regulatory functions. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Evaluation of selected acaricides against two-spotted spider mite (Acari: Tetranychidae) on greenhouse cotton using multispectral data

USDA-ARS?s Scientific Manuscript database

Two-spotted spider mite (TSSM), Tetranychus urticae (Koch), is an early season pest of cotton in the mid-southern United States and causes reduction in yield, fiber quality and impaired seed germination. Objectives of this study were to investigate the efficacy of abamectin and spiromesifen with two...

The underlying processes of a soil mite metacommunity on a small scale.

PubMed

Dong, Chengxu; Gao, Meixiang; Guo, Chuanwei; Lin, Lin; Wu, Donghui; Zhang, Limin

2017-01-01

Metacommunity theory provides an understanding of how ecological processes regulate local community assemblies. However, few field studies have evaluated the underlying mechanisms of a metacommunity on a small scale through revealing the relative roles of spatial and environmental filtering in structuring local community composition. Based on a spatially explicit sampling design in 2012 and 2013, this study aims to evaluate the underlying processes of a soil mite metacommunity on a small spatial scale (50 m) in a temperate deciduous forest located at the Maoershan Ecosystem Research Station, Northeast China. Moran's eigenvector maps (MEMs) were used to model independent spatial variables. The relative importance of spatial (including trend variables, i.e., geographical coordinates, and broad- and fine-scale spatial variables) and environmental factors in driving the soil mite metacommunity was determined by variation partitioning. Mantel and partial Mantel tests and a redundancy analysis (RDA) were also used to identify the relative contributions of spatial and environmental variables. The results of variation partitioning suggested that the relatively large and significant variance was a result of spatial variables (including broad- and fine-scale spatial variables and trend), indicating the importance of dispersal limitation and autocorrelation processes. The significant contribution of environmental variables was detected in 2012 based on a partial Mantel test, and soil moisture and soil organic matter were especially important for the soil mite metacommunity composition in both years. The study suggested that the soil mite metacommunity was primarily regulated by dispersal limitation due to broad-scale and neutral biotic processes at a fine-scale and that environmental filtering might be of subordinate importance. In conclusion, a combination of metacommunity perspectives between neutral and species sorting theories was suggested to be important in the observed structure of the soil mite metacommunity at the studied small scale.

The underlying processes of a soil mite metacommunity on a small scale

PubMed Central

Guo, Chuanwei; Lin, Lin; Wu, Donghui; Zhang, Limin

2017-01-01

Metacommunity theory provides an understanding of how ecological processes regulate local community assemblies. However, few field studies have evaluated the underlying mechanisms of a metacommunity on a small scale through revealing the relative roles of spatial and environmental filtering in structuring local community composition. Based on a spatially explicit sampling design in 2012 and 2013, this study aims to evaluate the underlying processes of a soil mite metacommunity on a small spatial scale (50 m) in a temperate deciduous forest located at the Maoershan Ecosystem Research Station, Northeast China. Moran’s eigenvector maps (MEMs) were used to model independent spatial variables. The relative importance of spatial (including trend variables, i.e., geographical coordinates, and broad- and fine-scale spatial variables) and environmental factors in driving the soil mite metacommunity was determined by variation partitioning. Mantel and partial Mantel tests and a redundancy analysis (RDA) were also used to identify the relative contributions of spatial and environmental variables. The results of variation partitioning suggested that the relatively large and significant variance was a result of spatial variables (including broad- and fine-scale spatial variables and trend), indicating the importance of dispersal limitation and autocorrelation processes. The significant contribution of environmental variables was detected in 2012 based on a partial Mantel test, and soil moisture and soil organic matter were especially important for the soil mite metacommunity composition in both years. The study suggested that the soil mite metacommunity was primarily regulated by dispersal limitation due to broad-scale and neutral biotic processes at a fine-scale and that environmental filtering might be of subordinate importance. In conclusion, a combination of metacommunity perspectives between neutral and species sorting theories was suggested to be important in the observed structure of the soil mite metacommunity at the studied small scale. PMID:28481906

Risk factors associated with the presence of Varroa destructor in honey bee colonies from east-central Argentina.

PubMed

Giacobino, A; Bulacio Cagnolo, N; Merke, J; Orellano, E; Bertozzi, E; Masciangelo, G; Pietronave, H; Salto, C; Signorini, M

2014-08-01

Varroa destructor is considered one of the major threats for worldwide apiculture. Damage caused by varroa mite includes body weight loss, malformation and weakening of the bees. It was also suggested as the main cause associated with colony winter mortality and as an important vector for several honey bee viruses. Little is known about multiple factors and their interaction affecting V. destructor prevalence in apiaries from South America. The aim of this study was to identify risk factors associated with V. destructor prevalence in east-central Argentina. Parasitic mite infestation level and colony strength measures were evaluated in 63 apiaries distributed in 4 different regions in east-central Argentina in a cross sectional study. Data regarding management practices in each apiary were collected by means of a questionnaire. A mixed-effects logistic regression model was constructed to associate management variables with the risk of achieving mite infestation higher than 3%. Colonies owned by beekeepers who indicated that they did not monitor colonies after mite treatment (OR=2.305; 95% CI: 0.944-5.629) nor disinfect hives woodenware material (OR=2.722; 95% CI: 1.380-5.565) were associated with an increased risk of presenting high intensity infestation with V. destructor (>3%). On the other hand, beekeepers who reported replacing more than 50% of the queens in their operation (OR=0.305; 95% CI: 0.107-0.872), feeding colonies protein substitute containing natural pollen (OR=0.348; 95% CI: 0.129-0.941) and feeding colonies High Fructose Corn Syrup (HFCS) (OR=0.108; 95% CI: 0.032-0.364), had colonies that were less likely to have V. destructor infestations above 3%, than beekeepers who did not report using these management practices. Further research should be conducted considering that certain management practices were associated to mite infestation level in order to improve the sanitary condition in the colonies. Epidemiological studies provide key information to design surveillance programs against one the major threat to worldwide beekeeping. Copyright © 2014 Elsevier B.V. All rights reserved.

Relative contribution of biotic and abiotic factors to the population density of the cassava green mite, Mononychellus tanajoa (Acari: Tetranychidae).

PubMed

Rêgo, Adriano S; Teodoro, Adenir V; Maciel, Anilde G S; Sarmento, Renato A

2013-08-01

The cassava green mite, Mononychellus tanajoa, is a key pest of cassava, Manihot esculenta Crantz (Euphorbiaceae), and it may be kept in check by naturally occurring predatory mites of the family Phytoseiidae. In addition to predatory mites, abiotic factors may also contribute to regulate pest mite populations in the field. Here, we evaluated the population densities of both M. tanajoa and the generalist predatory mite Euseius ho DeLeon (Acari: Phytoseiidae) over the cultivation cycle (11 months) of cassava in four study sites located around the city of Miranda do Norte, Maranhão, Brazil. The abiotic variables rainfall, temperature and relative humidity were also recorded throughout the cultivation cycle of cassava. We determined the relative importance of biotic (density of E. ho) and abiotic (rainfall, temperature and relative humidity) factors to the density of M. tanajoa. The density of M. tanajoa increased whereas the density of E. ho remained constant throughout time. A hierarchical partitioning analysis revealed that most of the variance for the density of M. tanajoa was explained by rainfall and relative humidity followed by E. ho density and temperature. We conclude that abiotic factors, especially rainfall, were the main mechanisms driving M. tanajoa densities.

Can we disrupt the sensing of honey bees by the bee parasite Varroa destructor?

PubMed

Eliash, Nurit; Singh, Nitin Kumar; Kamer, Yosef; Pinnelli, Govardhana Reddy; Plettner, Erika; Soroker, Victoria

2014-01-01

The ectoparasitic mite, Varroa destructor, is considered to be one of the most significant threats to apiculture around the world. Chemical cues are known to play a significant role in the host-finding behavior of Varroa. The mites distinguish between bees from different task groups, and prefer nurses over foragers. We examined the possibility of disrupting the Varroa--honey bee interaction by targeting the mite's olfactory system. In particular, we examined the effect of volatile compounds, ethers of cis 5-(2'-hydroxyethyl) cyclopent-2-en-1-ol or of dihydroquinone, resorcinol or catechol. We tested the effect of these compounds on the Varroa chemosensory organ by electrophysiology and on behavior in a choice bioassay. The electrophysiological studies were conducted on the isolated foreleg. In the behavioral bioassay, the mite's preference between a nurse and a forager bee was evaluated. We found that in the presence of some compounds, the response of the Varroa chemosensory organ to honey bee headspace volatiles significantly decreased. This effect was dose dependent and, for some of the compounds, long lasting (>1 min). Furthermore, disruption of the Varroa volatile detection was accompanied by a reversal of the mite's preference from a nurse to a forager bee. Long-term inhibition of the electrophysiological responses of mites to the tested compounds was a good predictor for an alteration in the mite's host preference. These data indicate the potential of the selected compounds to disrupt the Varroa--honey bee associations, thus opening new avenues for Varroa control.

Effect on quality of life of the mixed house dust mite/weed pollen extract immunotherapy.

PubMed

Li, Lisha; Guan, Kai

2016-07-01

Although many patients with allergic rhinitis have symptoms due to sensitization to more than one kind of allergens, and mixed allergen extracts are widely used for immunotherapy, there are few published trials. Our study aimed to evaluate the effect of multiple-allergen immunotherapy on improving the symptoms and quality of life of allergic rhinitis patients. We performed a 1-year single-center observation study of subcutaneous immunotherapy using house dust mite extract (n = 12), weed pollen extract (n = 21), or mixed house dust mite/weed pollen extract (n = 11) in 44 allergic rhinitis patients. All the allergens responsible for the symptom of each patient were included in his immunotherapy. Symptom score, medication score, and quality of life of the patients were evaluated before and after 1-year immunotherapy. Quality of life was evaluated with the Rhinoconjunctivitis Quality of Life Questionnaire. In all 3 groups receiving subcutaneous immunotherapy, significant improvement of symptom score, medication score, and quality of life was found vs. baseline at 1 year, irrespective of the allergen used. In the weed pollen season, the changes of quality of life questionnaire score after 1-year treatment were not significantly different between the weed pollen group (1.55 ± 1.24) and the mixed house dust mite/weed pollen group (1.14 ± 1.01). The same happened in the nonpollen seasons, during which dust mite immunotherapy (1.23 ± 1.63) and mixed immunotherapy (0.60 ± 0.47) did not show significantly different effect on the quality of life. The multiple-allergen immunotherapy might be effective in polysensitized allergic rhinitis patients, and could improve their quality of life. Our result did not show significant difference between the effects of multiple-allergen immunotherapy and mono-allergen immunotherapy.

Tolerance of the eriophyid mite Aceria salsolae to UV-A light and implications for biological control of Russian thistle.

PubMed

Moran, Patrick J; Wibawa, M Irene; Smith, Lincoln

2017-12-01

Aceria salsolae (Acari: Eriophyidae) is being evaluated as a candidate biological control agent of Russian thistle (Salsola tragus, Chenopodiaceae), a major invasive weed of rangelands and dryland crops in the western USA. Prior laboratory host range testing under artificial lighting indicated reproduction on non-native Bassia hyssopifolia and on a native plant, Suaeda calceoliformis. However, in field tests in the native range, mite populations released on these 'nontarget' plants remained low. We hypothesized that UV-A light, which can affect behavior of tetranychid mites, would affect populations of the eriophyid A. salsolae differently on the target and nontarget plant species, decreasing the mite's realized host range. Plants were infested with A. salsolae under lamps that emitted UV-A, along with broad-spectrum lighting, and the size of mite populations and plant growth was compared to infested plants exposed only to broad-spectrum light. Russian thistle supported 3- to 55-fold larger mite populations than nontarget plants regardless of UV-A treatment. UV-A exposure did not affect mite populations on Russian thistle or S. calceoliformis, whereas it increased populations 7-fold on B. hyssopifolia. Main stems on nontarget plants grew 2- to 6-fold faster than did Russian thistle under either light treatment. The two nontarget plants attained greater volume under the control light regime than UV-A, but Russian thistle was unaffected. Although Russian thistle was always the superior host, addition of UV-A light to the artificial lighting regime did not reduce the ability of A. salsolae to reproduce on the two nontarget species, suggesting that UV-B or other environmental factors may be more important in limiting mite populations in the field.

Efficacy of fipronil in the treatment of feline cheyletiellosis.

PubMed

Scarampella, F; Pollmeier, M; Visser, M; Boeckh, A; Jeannin, P

2005-05-15

The purpose of the present study was to confirm the efficacy of 10% (w/v) fipronil spot-on (Frontline spot-on for cats) in the treatment of feline cheyletiellosis under field conditions. A total of 16 cats of different breeds, sexes, 4 months to 14 years of age and weighing 0.5-6 kg were treated with a single topical application of 10% (w/v) fipronil spot-on according to label directions. The animals were naturally infested with Cheyletiella mites and housed in their normal environment throughout the study. Animals were selected based on clinical signs and infestation was confirmed by demonstration of mites. Mite counts and a clinical assessment of mite infestations (i.e. skin lesions and/or scales) were performed on days 0 and approximately days 14 and 28. Individual counts on day 0 ranged from 1 to 40 mites on individual animals. No mites were detected on cats treated with 10% (w/v) fipronil spot-on (Frontline spot-on for cats) at both post-treatment evaluations. Typical skin lesions and/or scales were present in all animals pre-treatment. In 56% of the cats, the lesions resolved within 14 days after treatment. At the final assessment, 75% cats were free of lesions. Two cats that still had clinical signs on day 28 were suspected of having allergic reactions to food or environmental allergens. The lesions on the remaining two cats could not be related to a specific cause. The efficacy of fipronil in elimination of mites was 100% on each occasion when compared to the pre-treatment count. The results of this study demonstrated that fipronil in a topical formulation is highly effective (100%) for the elimination of an existing Cheyletiella mite infestation under field conditions following a single topical application in cats.

Ectoparasite (louse, mite and tick) infestations on female turkeys (Galliformes, Phasianidae. Meleagris gallopavo) in Iran.

PubMed

Rassouli, Maryam; Darvishi, Mohammad Mahdi; Lima, Seyed Rasoul Rosstami

2016-12-01

Wild turkeys ( Meleagris gallopavo ) were evaluated as potential hosts of ectoparasites. Different lice, ticks and mites can infest turkeys and cause direct and/or indirect harms and in some cases can also be fatal. Samples (feathers) were collected from lateral parts of 15 and 7 female turkeys' body of two different turkey flocks, in Rasht, Gilan province and Piranshahr, Western Azerbaijan province, Iran, respectively. Feathers were inspected for ectoparasites, the collected ectoparasites were decolorized and mounted then identified by identification keys in parasitology laboratory. In this research, four new lice, one mite and one tick on 13 infested turkeys were identified and discussed.

Evaluation of airborne methyl salicylate for improved conservation biological control of two-spotted spider mite and hop aphid in Oregon hop yards

USDA-ARS?s Scientific Manuscript database

The use of synthetic herbivore-induced plant volatiles (HIPV) to attract natural enemies has received interest as a tool to enhance conservation biological control (CBC). Methyl salicylate (MeSA) is a HIPV that is attractive to several key predators of two-spotted spider mite, Tetranychus urticae K...

Evaluation of airborne methyl salicylate for improved conservation biological control of two-spotted spider mites and hop aphid in Oregon hop yards

USDA-ARS?s Scientific Manuscript database

The use of synthetic herbivore-induced plant volatiles (HIPV) to attract natural enemies has received interest as a tool to enhance conservation biological control (CBC). Methyl salicylate (MeSA) is a HIPV that is attractive to several key predators of two-spotted spider mite, Tetranychus urticae K...

Gentle Africanized bees on an oceanic island

PubMed Central

Rivera-Marchand, Bert; Oskay, Devrim; Giray, Tugrul

2012-01-01

Oceanic islands have reduced resources and natural enemies and potentially affect life history traits of arriving organisms. Among the most spectacular invasions in the Western hemisphere is that of the Africanized honeybee. We hypothesized that in the oceanic island Puerto Rico, Africanized bees will exhibit differences from the mainland population such as for defensiveness and other linked traits. We evaluated the extent of Africanization through three typical Africanized traits: wing size, defensive behavior, and resistance to Varroa destructor mites. All sampled colonies were Africanized by maternal descent, with over 65% presence of European alleles at the S-3 nuclear locus. In two assays evaluating defense, Puerto Rican bees showed low defensiveness similar to European bees. In morphology and resistance to mites, Africanized bees from Puerto Rico are similar to other Africanized bees. In behavioral assays on mechanisms of resistance to Varroa, we directly observed that Puerto Rican Africanized bees groomed-off and bit the mites as been observed in other studies. In no other location, Africanized bees have reduced defensiveness while retaining typical traits such as wing size and mite resistance. This mosaic of traits that has resulted during the invasion of an oceanic island has implications for behavior, evolution, and agriculture. PMID:23144660

Importance of including Blomia tropicalis in the routine diagnosis of Venezuelan patients with persistent allergic symptoms.

PubMed

Puccio, F A; Lynch, N R; Noya, O; Noga, O; Noda, A; Hagel, I; López, E; López, R; Caraballo, L; Mercado, D; DiPrisco, M C

2004-07-01

Blomia tropicalis is a common mite found in the house dust of many tropical countries including Venezuela. The prevalence of skin test and specific serum immunoglobulin (Ig)E reactivity to B. tropicalis in Venezuela has not been previously evaluated. In the present study we evaluated the skin reactivity by skin prick test and specific IgE by a multiple antigen blot assay, against B. tropicalis and Dermatophagoides pteronyssinus, in a group of 115 subjects who attended the Allergy Clinic of the Institute of Biomedicine, Caracas, Venezuela, and we studied possible cross reactions between similar proteins of these two mites. One hundred and six patients with persistent allergic respiratory symptoms showed a positive skin prick test to at least one of the mite extracts, with the frequency of positive reactions to B. tropicalis being as high as to D. pteronyssinus. Twelve patients reacted only to D. pteronyssinus and 13 different patients only to B. tropicalis. Specific IgE to each of the mite extracts was found with similar frequency, and the results coincided with the skin test reactivity. The study indicated the importance of including B. tropicalis in routine diagnostic testing in tropical and sub-tropical situations.

Revealing the Hyperdiverse Mite Fauna of Subarctic Canada through DNA Barcoding

PubMed Central

Young, Monica R.; Behan-Pelletier, Valerie M.; Hebert, Paul D. N.

2012-01-01

Although mites are one of the most abundant and diverse groups of arthropods, they are rarely targeted for detailed biodiversity surveys due to taxonomic constraints. We address this gap through DNA barcoding, evaluating acarine diversity at Churchill, Manitoba, a site on the tundra-taiga transition. Barcode analysis of 6279 specimens revealed nearly 900 presumptive species of mites with high species turnover between substrates and between forested and non-forested sites. Accumulation curves have not reached an asymptote for any of the three mite orders investigated, and estimates suggest that more than 1200 species of Acari occur at this locality. The coupling of DNA barcode results with taxonomic assignments revealed that Trombidiformes compose 49% of the fauna, a larger fraction than expected based on prior studies. This investigation demonstrates the efficacy of DNA barcoding in facilitating biodiversity assessments of hyperdiverse taxa. PMID:23133656

Geographic distribution and host plants of Raoiella indica and associated mite species in northern Venezuela.

PubMed

Vásquez, Carlos; de Moraes, Gilberto J

2013-05-01

The red palm mite (RPM), Raoiella indica Hirst (Acari: Tenuipalpidae), is an invasive pest in the New World, where it is currently considered a serious threat to coconut and banana crops. It was first reported from northern Venezuela in 2007. To determine its current distribution in this country, surveys were carried out from October 2008 to April 2010 on coconut (Cocos nucifera L.), banana (Musa spp.), ornamental plants and weeds in northern Venezuela. Higher population levels of RPM were registered on commercial coconut farms in Falcón and Sucre states but also on other plant species naturally growing along the coastal line in Anzoategui, Aragua, Carabobo, Monagas and Nueva Esparta states. Out of 34 botanical species evaluated, all RPM stages were observed only on eight arecaceous, one musaceous and one streliziaceous species, indicating that the pest developed and reproduced only on these plants. Mite specimens found on weeds were considered spurious events, as immature stages of the pest were never found on these. Amblyseius largoensis (Muma) (Acari: Phytoseiidae) was the most frequent predatory mite associated with RPM in all sampling sites. The results indicate that RPM has spread to extensive areas of northern Venezuela since its initial detection in Güiria, Sucre state. Considering the report of this pest mite in northern Brazil in the late 2009, additional samplings in southern Venezuela should be carried out, to evaluate the possible presence of RPM also in that region.

Toxicity of Selected Acaricides to Honey Bees (Apis mellifera) and Varroa (Varroa destructor Anderson and Trueman) and Their Use in Controlling Varroa within Honey Bee Colonies.

PubMed

Gregorc, Aleš; Alburaki, Mohamed; Sampson, Blair; Knight, Patricia R; Adamczyk, John

2018-05-10

The efficacies of various acaricides in order to control a parasitic mite, the Varroa mite, Varroa destructor , of honey bees, were measured in two different settings, namely, in laboratory caged honey bees and in queen-right honey bee colonies. The Varroa infestation levels before, during, and after the acaricide treatments were determined in two ways, namely: (1) using the sugar shake protocol to count mites on bees and (2) directly counting the dead mites on the hive bottom inserts. The acaricides that were evaluated were coumaphos, tau-fluvalinate, amitraz, thymol, and natural plant compounds (hop acids), which were the active ingredients. The acaricide efficacies in the colonies were evaluated in conjunction with the final coumaphos applications. All of the tested acaricides significantly increased the overall Varroa mortality in the laboratory experiment. Their highest efficiencies were recorded at 6 h post-treatment, except for coumaphos and thymol, which exhibited longer and more consistent activity. In the honey bee colonies, a higher Varroa mortality was recorded in all of the treatments, compared with the natural Varroa mortality during the pretreatment period. The acaricide toxicity to the Varroa mites was consistent in both the caged adult honey bees and workers in the queen-right colonies, although, two of these acaricides, coumaphos at the highest doses and hop acids, were comparatively more toxic to the worker bees.

Laboratory and field evaluation of an entomopathogenic fungus, Isaria cateniannulata strain 08XS-1, against Tetranychus urticae (Koch).

PubMed

Zhang, Xiaona; Jin, Daochao; Zou, Xiao; Guo, Jianjun

2016-05-01

The two-spotted mite, Tetranychus urticae Koch, is one of the most serious mite pests of crops throughout the world. Biocontrol of the mite with fungal agents has long been paid much attention because of the development of insecticide resistance and the severe restriction of chemical pesticides. In this study, the efficacy of submerged conidia of the entomopathogenic fungus Isaria cateniannulata strain 08XS-1 against T. urticae eggs, larvae and female adults was evaluated at different temperatures and humidity in the laboratory and under field conditions. The results showed that a suspension of 2 × 10(7) submerged conidia mL(-1) caused the highest mortalities of mite eggs, larvae and females (100, 100 and 70% respectively) at 100% relative humidity and 25 °C in the laboratory. In the field experiments against the mites, a suspension of 2 × 10(8) submerged conidia mL(-1) achieved significant efficiency - the relative control effects were 88.6, 83.8 and 83%, respectively, in cucumber, eggplant and bean fields after 10 days of treatment. The results suggest that the I. cateniannulata strain 08XS-1 is a potential fungal agent, with acceptable production cost of conidia, against T. urticae in the field in an area such as southwestern China with higher air humidity. © 2016 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

In vitro efficacy of ByeMite and Mite-Stop on developmental stages of the red chicken mite Dermanyssus gallinae.

PubMed

Abdel-Ghaffar, Fathy; Semmler, Margit; Al-Rasheid, Khaled; Mehlhorn, Heinz

2009-10-01

The present in vitro study shows the efficacy of two antimite products (ByeMite = phoxim, Mite-Stop = neem seed extract) against all developing stages of the important red chicken mite Dermanyssus gallinae (obtained at two farms in France and Germany). While permanent contact with the active compound led to an efficacy of 100% in the case of Mite-Stop on mites in both farms, there was only a 96.2% killing effect of ByeMite on the mites of the French farm. Even short contacts of only 4 s killed 100% of mites in the case of Mite-Stop at the French farm and only 84.5% in the German farm. ByeMite, on the other hand, killed only 27.8% (Germany) and 30% (France) when mites got the chance to escape from the treated grounds to untreated ones. When using only the half doses of both products, Mite-Stop(R) still reached, after permanent contact, 100% activity on the German farm and 98.2% in France, while ByeMite killed 93.8% (Germany) and 90.6% (France). Short contact to half doses of course reduced the activity of both products (Mite-Stop = 59.3% in France, 22.1% in Germany; ByeMite = 28.8% in France, 18.8% in Germany). With respect to the fumigant activity of the products, the strains of D. gallinae reacted differently. While Mite-Stop(R) showed a clear fumigant activity in the case of the German mites, this product did not affect the French mites by air distribution, neither did ByeMite in both cases. Therefore, mites have to come in contact with both products. Against Mite-Stop, there was apparently no resistance and low doses have high efficacy after even short contacts, which regularly occur in a treated stable, where mites have the chance to leave treated places to untreated hidden spots.

Novel Mutations in the Voltage-Gated Sodium Channel of Pyrethroid-Resistant Varroa destructor Populations from the Southeastern USA.

PubMed

González-Cabrera, Joel; Rodríguez-Vargas, Sonia; Davies, T G Emyr; Field, Linda M; Schmehl, Daniel; Ellis, James D; Krieger, Klemens; Williamson, Martin S

2016-01-01

The parasitic mite Varroa destructor has a significant worldwide impact on bee colony health. In the absence of control measures, parasitized colonies invariably collapse within 3 years. The synthetic pyrethroids tau-fluvalinate and flumethrin have proven very effective at managing this mite within apiaries, but intensive control programs based mainly on one active ingredient have led to many reports of pyrethroid resistance. In Europe, a modification of leucine to valine at position 925 (L925V) of the V. destructor voltage-gated sodium channel was correlated with resistance, the mutation being found at high frequency exclusively in hives with a recent history of pyrethroid treatment. Here, we identify two novel mutations, L925M and L925I, in tau-fluvalinate resistant V. destructor collected at seven sites across Florida and Georgia in the Southeastern region of the USA. Using a multiplexed TaqMan® allelic discrimination assay, these mutations were found to be present in 98% of the mites surviving tau-fluvalinate treatment. The mutations were also found in 45% of the non-treated mites, suggesting a high potential for resistance evolution if selection pressure is applied. The results from a more extensive monitoring programme, using the Taqman® assay described here, would clearly help beekeepers with their decision making as to when to include or exclude pyrethroid control products and thereby facilitate more effective mite management programmes.

Can We Disrupt the Sensing of Honey Bees by the Bee Parasite Varroa destructor?

PubMed Central

Eliash, Nurit; Singh, Nitin Kumar; Kamer, Yosef; Pinnelli, Govardhana Reddy; Plettner, Erika; Soroker, Victoria

2014-01-01

Background The ectoparasitic mite, Varroa destructor, is considered to be one of the most significant threats to apiculture around the world. Chemical cues are known to play a significant role in the host-finding behavior of Varroa. The mites distinguish between bees from different task groups, and prefer nurses over foragers. We examined the possibility of disrupting the Varroa – honey bee interaction by targeting the mite's olfactory system. In particular, we examined the effect of volatile compounds, ethers of cis 5-(2′-hydroxyethyl) cyclopent-2-en-1-ol or of dihydroquinone, resorcinol or catechol. We tested the effect of these compounds on the Varroa chemosensory organ by electrophysiology and on behavior in a choice bioassay. The electrophysiological studies were conducted on the isolated foreleg. In the behavioral bioassay, the mite's preference between a nurse and a forager bee was evaluated. Principal findings We found that in the presence of some compounds, the response of the Varroa chemosensory organ to honey bee headspace volatiles significantly decreased. This effect was dose dependent and, for some of the compounds, long lasting (>1 min). Furthermore, disruption of the Varroa volatile detection was accompanied by a reversal of the mite's preference from a nurse to a forager bee. Long-term inhibition of the electrophysiological responses of mites to the tested compounds was a good predictor for an alteration in the mite's host preference. Conclusions These data indicate the potential of the selected compounds to disrupt the Varroa - honey bee associations, thus opening new avenues for Varroa control. PMID:25226388

Identification and evaluation of vaccine candidate antigens from the poultry red mite (Dermanyssus gallinae)

PubMed Central

Bartley, Kathryn; Wright, Harry W.; Huntley, John F.; Manson, Erin D.T.; Inglis, Neil F.; McLean, Kevin; Nath, Mintu; Bartley, Yvonne; Nisbet, Alasdair J.

2015-01-01

An aqueous extract of the haematophagous poultry ectoparasite, Dermanyssus gallinae, was subfractionated using anion exchange chromatography. Six of these subfractions were used to immunise hens and the blood from these hens was fed, in vitro, to poultry red mites. Mite mortality following these feeds was indicative of protective antigens in two of the subfractions, with the risks of mites dying being 3.1 and 3.7 times higher than in the control group (P < 0.001). A combination of two-dimensional immunoblotting and immunoaffinity chromatography, using IgY from hens immunised with these subfractions, was used in concert with proteomic analyses to identify the strongest immunogenic proteins in each of these subfractions. Ten of the immunoreactive proteins were selected for assessment as vaccine candidates using the following criteria: intensity of immune recognition; likelihood of exposure of the antigen to the antibodies in a blood meal; proposed function and known vaccine potential of orthologous molecules. Recombinant versions of each of these 10 proteins were produced in Escherichia coli and were used to immunise hens. Subsequent in vitro feeding of mites on blood from these birds indicated that immunisation with Deg-SRP-1 (serpin), Deg-VIT-1 (vitellogenin), Deg-HGP-1 (hemelipoglycoprotein) or Deg-PUF-1 (a protein of unknown function) resulted in significantly increased risk of mite death (1.7–2.8 times higher than in mites fed blood from control hens immunised with adjuvant only, P < 0.001). The potential for using these antigens in a recombinant vaccine is discussed. PMID:26296690

Identification and evaluation of vaccine candidate antigens from the poultry red mite (Dermanyssus gallinae).

PubMed

Bartley, Kathryn; Wright, Harry W; Huntley, John F; Manson, Erin D T; Inglis, Neil F; McLean, Kevin; Nath, Mintu; Bartley, Yvonne; Nisbet, Alasdair J

2015-11-01

An aqueous extract of the haematophagous poultry ectoparasite, Dermanyssus gallinae, was subfractionated using anion exchange chromatography. Six of these subfractions were used to immunise hens and the blood from these hens was fed, in vitro, to poultry red mites. Mite mortality following these feeds was indicative of protective antigens in two of the subfractions, with the risks of mites dying being 3.1 and 3.7 times higher than in the control group (P<0.001). A combination of two-dimensional immunoblotting and immunoaffinity chromatography, using IgY from hens immunised with these subfractions, was used in concert with proteomic analyses to identify the strongest immunogenic proteins in each of these subfractions. Ten of the immunoreactive proteins were selected for assessment as vaccine candidates using the following criteria: intensity of immune recognition; likelihood of exposure of the antigen to the antibodies in a blood meal; proposed function and known vaccine potential of orthologous molecules. Recombinant versions of each of these 10 proteins were produced in Escherichia coli and were used to immunise hens. Subsequent in vitro feeding of mites on blood from these birds indicated that immunisation with Deg-SRP-1 (serpin), Deg-VIT-1 (vitellogenin), Deg-HGP-1 (hemelipoglycoprotein) or Deg-PUF-1 (a protein of unknown function) resulted in significantly increased risk of mite death (1.7-2.8times higher than in mites fed blood from control hens immunised with adjuvant only, P<0.001). The potential for using these antigens in a recombinant vaccine is discussed. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Clinical and Immunological Changes of Immunotherapy in Patients with Atopic Dermatitis: Randomized Controlled Trial

PubMed Central

Sánchez Caraballo, Jorge Mario; Cardona Villa, Ricardo

2012-01-01

Background. Immunotherapy has proven to be an useful tool in the management of allergic respiratory diseases; however, little has been studied in atopic dermatitis. Objective. To evaluate the clinical and immunological impact of immunotherapy with mites allergen extracts in atopic dermatitis. Methods. Patients with atopic dermatitis were assigned with computer-generated randomization to either of the following groups: (a) controls received only topical treatment with steroids and/or tacrolimus and (b) actively treated patients received topical treatment plus immunotherapy. Levels of serum total IgE, mites-specific IgE and IgG4 were assessed at study start and after one year of immunotherapy. Results. 31 patients in the active group and 29 in the control group completed the study. Symptoms and medication scores were significantly reduced in the active group after six months. Three patients in the control group showed new sensitizations to mites, while 3 patients in the active group showed neosensitization to shrimp with negative oral food challenge. We observed significant increase of mites-specific IgG4 levels in active group. Conclusion. Specific allergen immunotherapy induced a tolerogenic IgG4 response to mite allergens associated with favorable clinical effects in atopic dermatitis patients. PMID:23724240

The evaluation of extraction techniques for Tetranychus urticae (Acari: Tetranychidae) from apple (Malus domestica) and cherry (Prunus avium) leaves.

PubMed

Harris, Adrian L; Ullah, Roshan; Fountain, Michelle T

2017-08-01

Tetranychus urticae is a widespread polyphagous mite, found on a variety of fruit crops. Tetranychus urticae feeds on the underside of the leaves perforating plant cells and sucking the cell contents. Foliar damage and excess webbing produced by T. urticae can reduce fruit yield. Assessments of T. urticae populations while small provide reliable and accurate ways of targeting control strategies and recording their efficacy against T. urticae. The aim of this study was to evaluate four methods for extracting low levels of T. urticae from leaf samples, representative of developing infestations. These methods were compared to directly counting of mites on leaves under a dissecting microscope. These methods were ethanol washing, a modified paraffin/ethanol meniscus technique, Tullgren funnel extraction and the Henderson and McBurnie mite brushing machine with consideration to: accuracy, precision and simplicity. In addition, two physically different leaf morphologies were compared; Prunus leaves which are glabrous with Malus leaves which are setaceous. Ethanol extraction consistently yielded the highest numbers of mites and was the most rapid method for recovering T. urticae from leaf samples, irrespective of leaf structure. In addition the samples could be processed and stored before final counting. The advantages and disadvantages of each method are discussed in detail.

USDA-ARS extension activities in medical, veterinary and urban entomology

USDA-ARS?s Scientific Manuscript database

Within the USDA Agricultural Research Service (USDA-ARS), National Program 104 conducts research on veterinary, medical, and urban entomology. The goal of this program is to develop more effective methods of preventing or suppressing insects, ticks, and mites that affect animal and human well-being....

Biological studies of Oligonychus punicae (Acari: Tetranychidae) on grapevine cultivars.

PubMed

Vásquez, Carlos; Aponte, Orlando; Morales, José; Sanabria, María E; García, Grisaly

2008-06-01

Life cycle, fecundity and longevity of the avocado brown mite, Oligonychus punicae (Hirst), were studied on six grapevine cultivars (Tucupita, Villanueva, Red Globe, Sirah, Sauvignon and Chenin Blanc), under laboratory conditions at 27 +/- 2 degrees C, 80 +/- 10% RH, and L12:D12 photoperiod. Mite-infested leaves were collected from vineyards, placed in paper bags and taken to the laboratory. A laboratory mite culture was established using the grape cultivar Criolla Negra as host plant. To elucidate potential effects on avocado brown mite parameters, we assessed levels of secondary metabolites, such as alkaloids, flavonoids, tannins and polyphenols, of leaves of the six grape cultivars, as well as the thickness of the adaxial cuticle-epidermis. The life cycle of O. punicae differed among cultivars with average values ranging between 8.2 days on Tucupita leaves and 9.1 days on Sirah. Relatively high fecundity was found on Tucupita leaves (2.8 eggs/female/day) during 11.4 oviposition days, while low fecundity values occurred on Sirah and Villanueva leaves, with 0.9 and 1.8 eggs/female/day during 7.9 and 6.7 days, respectively. Average longevity of O. punicae females ranged from 8.1 to 17.5 days on Sirah and Sauvignon leaves, respectively. Intrinsic rate of increase (r (m)) was highest on Sauvignon (0.292) and Tucupita (0.261), and lowest on Sirah (0.146) and Villanueva (0.135). Although significant differences in cuticle-epidermis thickness were detected among the six cultivars, it seemed not to affect mite parameters. Secondary metabolite content also varied between the cultivars. Generally, increasing flavonoid content coincided with decreasing reproductive parameters. The natural plant resistance observed in this study could be useful in the development of an integrated pest management program for mite pests in grape production.

Research project for increasing pool of minority engineers

NASA Technical Reports Server (NTRS)

Rogers, Decatur B.

1995-01-01

The Tennessee State University (TSU) Research Project for Increasing the Pool of Minority Engineers is designed to develop engineers who have academic and research experiences in technical areas of interest to NASA. These engineers will also have some degree of familiarity with NASA Lewis Research Center as a result of interaction with Lewis engineers, field trips and internships at Lewis. The Research Project has four components, which are: (1) Minority Introduction to Engineering (MITE), a high school precollege program, (2) engineering and technology previews, (3) the NASA LeRC Scholars program which includes scholarships and summer internships, and (4) undergraduate research experiences on NASA sponsored research. MITE is a two-week summer engineering camp designed to introduce minority high school students to engineering by exposing them to: (1) engineering role models (engineering students and NASA engineer), (2) field trips to engineering firms, (3) in addition to introducing youth to the language of the engineer (i.e., science, mathematics, technical writing, computers, and the engineering laboratory). Three MITE camps are held on the campus of TSU with an average of 40 participants. MITE has grown from 25 participants at its inception in 1990 to 118 participants in 1994 with participants from 17 states, including the District of Columbia, and 51 percent of the participants were female. Over the four-year period, 77 percent of the seniors who participated in MITE have gone to college, while 53 percent of those seniors in college are majoring in science, engineering or mathematics (SEM). This first Engineering and Technology Previews held in 1993 brought 23 youths from Cleveland, Ohio to TSU for a two-day preview of engineering and college life. Two previews are scheduled for 1994-1995. The NASA LeRC Scholars program provides scholarships and summer internships for minority engineering students majoring in electrical or mechanical engineering. Presently six (6) engineering students are in the Scholars program. The average GPA for the scholars is 3.239. Each scholar must maintain a minimum GPA of 3.000/4.000. NASA LeRC Fred Higgs has been awarded a GEM Fellowship. In addition, he will be presenting a paper entitled 'Design of Helical Spring Using Probabilistic Design Methodology' at the Middle Tennessee Section ASME Student Design Presentations in Nashville on March 23rd and at the National Conference on Undergraduate Research to be held at Union College, Schenectady, New York on April 20-22, 1995. Each of the scholars is working on one of the three NASA sponsored research projects in the college.

Comparative Demography of the Spider Mite, Oligonychus afrasiaticus, on four Date Palm Varieties in Southwestern Tunisia

PubMed Central

Chaaban, Sameh Ben; Chermiti, Brahim; Kreiter, Serge

2011-01-01

The date palm mite, Oligonychus afrasiaticus (McGregor) (Acari: Tetranychidae), is a serious pest of palm date fruits. Life cycle, fecundity, and longevity of this mite were studied on fruits of four date palms, Phoenix dactylifera L. (Arecales: Arecaceae)(varieties: Deglet Noor, Alig, Kentichi, and Besser), under laboratory conditions at 27 = 1 °C, 60 ± 10% RH. Total development time of immature female was shorter on Deglet Noor fruits than on the other cultivars. O. afrasiaticus on Deglet Noor had the highest total fecundity per female, while low fecundity values occurred on Besser. The comparison of intrinsic rates of natural increase (rm), net reproductive rates (Ro), and the survival rates of immature stage of O. afrasiaticus on the host plants suggests that O. afrasiaticus performs better on Deglet Noor fruits. The mite feeding on Alig showed the lowest intrinsic rate of natural population increase (rm = 0.103 day 1). The estimation of difference in susceptibility of cultivars to O. afrasiaticus is crucial for developing efficient pest control programs. Indeed, less susceptible cultivars can either be left unsprayed or sprayed at low threshold. PMID:22233420

Demodex spp. Infestation Associated with Treatment-Resistant Chalazia and Folliculitis.

PubMed

Akçınar, Ulviye Güvendi; Ünal, Emine; Akpınar, Metin

2016-12-01

Demodecidosis is an ectoparasitosis of pilosebaceous unit caused by demodex mites. The disease may be a primary skin disease or a secondary disease to inflammatory dermatoses such as folliculitis and rosacea. Demodex spp. blepharitis is an infectious ocular disease that is common but always neglected. These mites contain lipase enzymes that help carry bacteria on the surface. The infestation of Demodex spp. has increasingly become a public health concern. A 29-year-old male patient was admitted to our dermatology clinic with a complaint of papules and pustules on his face, which started 4 years ago. A standardized skin biopsy specimen was evaluated in our microbiology laboratory, and we detected Demodex folliculorum mites on his face (3+). There was pruritus of his eyes. A total of four eyelashes were epilated and were then examined under a light microscope for the presence of Demodex infestation. In this study, we discussed the association between acne rocacea, blepharitis, and demodex mites.

Autofluorescence microscopy for paired-matched morphological and molecular identification of individual chigger mites (Acari: Trombiculidae), the vectors of scrub typhus.

PubMed

Kumlert, Rawadee; Chaisiri, Kittipong; Anantatat, Tippawan; Stekolnikov, Alexandr A; Morand, Serge; Prasartvit, Anchana; Makepeace, Benjamin L; Sungvornyothin, Sungsit; Paris, Daniel H

2018-01-01

Conventional gold standard characterization of chigger mites involves chemical preparation procedures (i.e. specimen clearing) for visualization of morphological features, which however contributes to destruction of the arthropod host DNA and any endosymbiont or pathogen DNA harbored within the specimen. In this study, a novel work flow based on autofluorescence microscopy was developed to enable identification of trombiculid mites to the species level on the basis of morphological traits without any special preparation, while preserving the mite DNA for subsequent genotyping. A panel of 16 specifically selected fluorescence microscopy images of mite features from available identification keys served for complete chigger morphological identification to the species level, and was paired with corresponding genotype data. We evaluated and validated this method for paired chigger morphological and genotypic ID using the mitochondrial cytochrome c oxidase subunit I gene (coi) in 113 chigger specimens representing 12 species and 7 genera (Leptotrombidium, Ascoschoengastia, Gahrliepia, Walchia, Blankaartia, Schoengastia and Schoutedenichia) from the Lao People's Democratic Republic (Lao PDR) to the species level (complete characterization), and 153 chiggers from 5 genera (Leptotrombidium, Ascoschoengastia, Helenicula, Schoengastiella and Walchia) from Thailand, Cambodia and Lao PDR to the genus level. A phylogenetic tree constructed from 77 coi gene sequences (approximately 640 bp length, n = 52 new coi sequences and n = 25 downloaded from GenBank), demonstrated clear grouping of assigned morphotypes at the genus levels, although evidence of both genetic polymorphism and morphological plasticity was found. With this new methodology, we provided the largest collection of characterized coi gene sequences for trombiculid mites to date, and almost doubled the number of available characterized coi gene sequences with a single study. The ability to provide paired phenotypic-genotypic data is of central importance for future characterization of mites and dissecting the molecular epidemiology of mites transmitting diseases like scrub typhus.

Autofluorescence microscopy for paired-matched morphological and molecular identification of individual chigger mites (Acari: Trombiculidae), the vectors of scrub typhus

PubMed Central

Chaisiri, Kittipong; Anantatat, Tippawan; Stekolnikov, Alexandr A.; Morand, Serge; Prasartvit, Anchana; Makepeace, Benjamin L.; Sungvornyothin, Sungsit; Paris, Daniel H.

2018-01-01

Background Conventional gold standard characterization of chigger mites involves chemical preparation procedures (i.e. specimen clearing) for visualization of morphological features, which however contributes to destruction of the arthropod host DNA and any endosymbiont or pathogen DNA harbored within the specimen. Methodology/Principal findings In this study, a novel work flow based on autofluorescence microscopy was developed to enable identification of trombiculid mites to the species level on the basis of morphological traits without any special preparation, while preserving the mite DNA for subsequent genotyping. A panel of 16 specifically selected fluorescence microscopy images of mite features from available identification keys served for complete chigger morphological identification to the species level, and was paired with corresponding genotype data. We evaluated and validated this method for paired chigger morphological and genotypic ID using the mitochondrial cytochrome c oxidase subunit I gene (coi) in 113 chigger specimens representing 12 species and 7 genera (Leptotrombidium, Ascoschoengastia, Gahrliepia, Walchia, Blankaartia, Schoengastia and Schoutedenichia) from the Lao People’s Democratic Republic (Lao PDR) to the species level (complete characterization), and 153 chiggers from 5 genera (Leptotrombidium, Ascoschoengastia, Helenicula, Schoengastiella and Walchia) from Thailand, Cambodia and Lao PDR to the genus level. A phylogenetic tree constructed from 77 coi gene sequences (approximately 640 bp length, n = 52 new coi sequences and n = 25 downloaded from GenBank), demonstrated clear grouping of assigned morphotypes at the genus levels, although evidence of both genetic polymorphism and morphological plasticity was found. Conclusions/Significance With this new methodology, we provided the largest collection of characterized coi gene sequences for trombiculid mites to date, and almost doubled the number of available characterized coi gene sequences with a single study. The ability to provide paired phenotypic-genotypic data is of central importance for future characterization of mites and dissecting the molecular epidemiology of mites transmitting diseases like scrub typhus. PMID:29494599

Identification of novel MITEs (miniature inverted-repeat transposable elements) in Coxiella burnetii: implications for protein and small RNA evolution.

PubMed

Wachter, Shaun; Raghavan, Rahul; Wachter, Jenny; Minnick, Michael F

2018-04-11

Coxiella burnetii is a Gram-negative gammaproteobacterium and zoonotic agent of Q fever. C. burnetii's genome contains an abundance of pseudogenes and numerous selfish genetic elements. MITEs (miniature inverted-repeat transposable elements) are non-autonomous transposons that occur in all domains of life and are thought to be insertion sequences (ISs) that have lost their transposase function. Like most transposable elements (TEs), MITEs are thought to play an active role in evolution by altering gene function and expression through insertion and deletion activities. However, information regarding bacterial MITEs is limited. We describe two MITE families discovered during research on small non-coding RNAs (sRNAs) of C. burnetii. Two sRNAs, Cbsr3 and Cbsr13, were found to originate from a novel MITE family, termed QMITE1. Another sRNA, CbsR16, was found to originate from a separate and novel MITE family, termed QMITE2. Members of each family occur ~ 50 times within the strains evaluated. QMITE1 is a typical MITE of 300-400 bp with short (2-3 nt) direct repeats (DRs) of variable sequence and is often found overlapping annotated open reading frames (ORFs). Additionally, QMITE1 elements possess sigma-70 promoters and are transcriptionally active at several loci, potentially influencing expression of nearby genes. QMITE2 is smaller (150-190 bps), but has longer (7-11 nt) DRs of variable sequences and is mainly found in the 3' untranslated region of annotated ORFs and intergenic regions. QMITE2 contains a GTAG repetitive extragenic palindrome (REP) that serves as a target for IS1111 TE insertion. Both QMITE1 and QMITE2 display inter-strain linkage and sequence conservation, suggesting that they are adaptive and existed before divergence of C. burnetii strains. We have discovered two novel MITE families of C. burnetii. Our finding that MITEs serve as a source for sRNAs is novel. QMITE2 has a unique structure and occurs in large or small versions with unique DRs that display linkage and sequence conservation between strains, allowing for tracking of genomic rearrangements. QMITE1 and QMITE2 copies are hypothesized to influence expression of neighboring genes involved in DNA repair and virulence through transcriptional interference and ribonuclease processing.

Resistance to Arrenurus spp. Parasitism in Odonates: Patterns Across Species and Comparisons Between a Resistant and Susceptible Host.

PubMed

Worthen, Wade B; Hart, Thomas M

2016-01-01

Some adult odonates resist parasitism by larval water mites (Arrenurus spp.) with melanotic encapsulation, in which the mite's stylestome is clogged and the mite starves. In summer 2014, we counted the engorged and resisted mites on 2,729 adult odonates sampled by aerial net at 11 water bodies in Greenville Co. and Pickens Co., SC, and tested the hypothesis that the frequency and intensity of resistance correlates with parasite prevalence (the percentage of parasitized hosts). Resistance prevalence (the percentage of parasitized hosts that resisted at least one mite) varied significantly among host species, exceeding 60% for Argia fumipennis(Burmeister) and Celithemis fasciata Kirby but less than 20% for other species. However, neither resistance prevalence nor mean resistance intensity (mean percentage of resisted mites on resisting hosts) correlated with parasite prevalence. We described potential effects of parasitism on host development ofA. fumipennis and Pachydiplax longipennis(Burmeister) by comparing the percent asymmetry of forewing lengths between parasitized and unparasitized individuals. There was no significant difference in asymmetry for either males or females of A. fumipennis, or males of Pa. longipennis(females were not sampled). We also evaluated differences in melanotic encapsulation between A. fumipennis, which readily encapsulates mites in nature, and Pa. longipennis We inserted a 2.0-mm piece of sterile monofilament line into the thorax of captured individuals for 24 h and compared mean gray value scores of inserted and emergent ends using Image-J software. There was no difference in melanotic encapsulation between species. © The Author 2016. Published by Oxford University Press on behalf of the Entomological Society of America.

Validation of a novel epicutaneous delivery system for patch testing of house dust mite-hypersensitive dogs.

PubMed

Olivry, Thierry; Linder, Keith E; Paps, Judy S; Bizikova, Petra; Dunston, Stan; Donne, Nathalie; Mondoulet, Lucie

2012-12-01

Patch tests with allergens are used for the evaluation of cellular hypersensitivity to food and environmental allergens in dogs and humans with atopic dermatitis. Viaskin is a novel allergen epicutaneous delivery system that enhances epidermal allergen capture by immune cells. To compare the use of Viaskin and Finn chamber patch tests in dogs hypersensitive to mite allergens. Empty control or Dermatophagoides farinae house dust mite-containing Viaskin or Finn chamber patches were applied to the thoracic skin of six mite-hypersensitive Maltese-beagle crossbred atopic dogs. Lesions were graded 49 and 72 h after patch test application, and skin biopsies were collected after 72 h. Overall microscopic inflammation, eosinophil and T-lymphocyte infiltrations were scored. Positive macroscopic patch test reactions developed at five of six Viaskin application sites and four of six Finn chamber application sites. Median microscopic epidermal and dermal inflammation, as well as eosinophil and CD3 T-lymphocyte dermal scores were always higher in biopsies collected at Viaskin than at Finn chamber sites. Microscopic inflammation scores were significantly higher after mite allergen-containing Viaskin compared with empty patches, but this was not the case for mite-containing Finn chambers compared with control chambers. Scores obtained using Viaskin were not significantly different from those obtained using Finn chambers. Macroscopic and microscopic scores were significantly correlated. In mite-allergic dogs, Viaskin epicutaneous delivery systems appear to induce stronger allergen-specific inflammation than currently used Finn chamber patch tests. Consequently, Viaskin patches might offer a better alternative for screening cellular hypersensitivity to food and environmental allergens. © 2012 The Authors. Veterinary Dermatology © 2012 ESVD and ACVD.

Allergen sensitisation among chronic respiratory diseases in urban and rural areas of the south of Viet Nam.

PubMed

Chu, H T; Godin, I; Phuong, N T; Nguyen, L H; Hiep, T T M; Michel, O

2018-02-01

To evaluate the prevalence of and risk factors for allergen sensitisation among patients with chronic respiratory disease (CRD) in southern Viet Nam. An environmental questionnaire and skin prick tests for airborne and food allergens were administered to patients with CRD, defined as individuals with respiratory symptoms and lung function defects. Of 610 CRD patients, 56% had chronic obstructive pulmonary disease and 31% were asthma patients; 80% were males. The most frequent sensitisers were dust mites (Dermatophagoides farinae 22%, Blomia tropicalis 19%, D. pteronyssinus 18%) and cockroach droppings (13%). Among study participants, 37% were from rural settings and 36% from urban areas, whereas 27% had migrated from rural to urban areas. Compared with people from rural areas, being born in an urban area was a risk factor for sensitisation to mites (OR 1.56, 95%CI 1.11-2.20, P < 0.02). In multivariate analysis, place of birth remained a risk factor for mite sensitisation. Compared with the native urban population, the risk of mite sensitisation was not significantly different among patients born in rural areas and those migrating to urban areas. Dust mites and cockroach droppings were the most frequent allergens among people with CRD in the south of Viet Nam. Compared with the urban population, being native to a rural area was protective against mite sensitisation, but this effect ceased to be significant after migration from rural to urban areas.

Comparison of atopy patch testing to skin prick testing for diagnosing mite-induced atopic dermatitis: a systematic review and meta-analysis.

PubMed

Liu, Yumei; Peng, Jianglong; Zhou, Ying; Cui, Yubao

2017-01-01

Atopic dermatitis (AD) can occur after contact with aeroallergens like house dust mites, pollen, and animal dander. Despite its controversial diagnostic value, the atopy patch test (APT) has been used as an important tool in the diagnosis of AD caused by house dust mites. Here, we present a meta-analysis comparing APT to the common skin prick test (SPT) in the diagnosis of mite-induced AD. A structured search was performed using online databases and bibliographies published as of April 30, 2017. All studies evaluating the accuracy of APT and SPT in the diagnosis of mite-induced atopic eczema/dermatitis syndrome were selected, appraised, and data was extracted. Ten studies were identified for inclusion in our analysis. Meta-analysis revealed that the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratios for APT were 0.54 (95% CI 0.42-0.66), 0.72 (95% CI 0.56-0.85), 1.97 (95% CI 1.20-3.23), 0.63 (95% CI 0.48-0.83), and 3.12 (95% CI 1.53-6.39). The area under the summary receiver operating characteristic curve was 0.65 (95% CI 0.61-0.69). Our analysis indicates that APT is a useful tool in the screening of mite-induced AD, although this conclusion must be interpreted cautiously due to high heterogeneity among the included studies.

Dermatoses associated with mites other than Sarcoptes.

PubMed

Ken, Kimberly M; Shockman, Solomon C; Sirichotiratana, Melissa; Lent, Megan P; Wilson, Morgan L

2014-09-01

Mites are arthropods of the subclass Acari (Acarina). Although Sarcoptes is the mite most commonly recognized as a cause of human skin disease in the United States, numerous other mite-associated dermatoses have been described, and merit familiarity on the part of physicians treating skin disease. This review discusses several non-scabies mites and their associated diseases, including Demodex, chiggers, Cheyletiella, bird mites, grain itch, oak leaf itch, grocer's itch, tropical rat mite, snake mite, and Psoroptes.

Novel Mutations in the Voltage-Gated Sodium Channel of Pyrethroid-Resistant Varroa destructor Populations from the Southeastern USA

PubMed Central

González-Cabrera, Joel; Rodríguez-Vargas, Sonia; Davies, T. G. Emyr; Field, Linda M.; Schmehl, Daniel; Ellis, James D.; Krieger, Klemens; Williamson, Martin S.

2016-01-01

The parasitic mite Varroa destructor has a significant worldwide impact on bee colony health. In the absence of control measures, parasitized colonies invariably collapse within 3 years. The synthetic pyrethroids tau-fluvalinate and flumethrin have proven very effective at managing this mite within apiaries, but intensive control programs based mainly on one active ingredient have led to many reports of pyrethroid resistance. In Europe, a modification of leucine to valine at position 925 (L925V) of the V. destructor voltage-gated sodium channel was correlated with resistance, the mutation being found at high frequency exclusively in hives with a recent history of pyrethroid treatment. Here, we identify two novel mutations, L925M and L925I, in tau-fluvalinate resistant V. destructor collected at seven sites across Florida and Georgia in the Southeastern region of the USA. Using a multiplexed TaqMan® allelic discrimination assay, these mutations were found to be present in 98% of the mites surviving tau-fluvalinate treatment. The mutations were also found in 45% of the non-treated mites, suggesting a high potential for resistance evolution if selection pressure is applied. The results from a more extensive monitoring programme, using the Taqman® assay described here, would clearly help beekeepers with their decision making as to when to include or exclude pyrethroid control products and thereby facilitate more effective mite management programmes. PMID:27191597

Prevalence of fur mites in pet rabbits in South Korea.

PubMed

Kim, Sang-Hun; Jun, Hyung-Kyou; Song, Kun-Ho; Gram, Dunbar; Kim, Duck-Hwan

2008-06-01

The prevalence of fur mites, Cheyletiella parasitovorax and Leporacarus gibbus, in pet rabbits in South Korea was investigated by a diagnostic evaluation of skin surface tape strips and hair coat combings. C. parasitovorax was found in 80 of 140 rabbits (57.1%) and L. gibbus in six of 140 rabbits (4.3%). Clinical signs of pruritus and scaling were observed in 17 of 80 and 76 of 80 infested rabbits, respectively.

The influence of household pets on the composition and quantity of allergenic mite fauna within Irish homes: a preliminary investigation.

PubMed

Clarke, D; Dix, E; Liddy, S; Gormally, M; Byrne, M

2016-03-01

Allergenic mites are responsible for inducing hypersensitive reactions in genetically predisposed people worldwide. Mites in dust from 30 Irish homes with pets (dogs, n = 23; cats, n = 7) were compared with those in 30 homes without pets. House dust mites constituted 78% of all mites recorded, with Dermatophagoides pteronyssinus (Acariformes: Pyroglyphidae) representing 57-72% of mites in furniture and mattresses in both home types compared with only 22% of mites in pet beds. Although storage mites accounted for just 13% of all mites recorded, they represented 46% of mites recorded in pet beds. Median levels of the dust mite allergen Der p 1 (µg/g) in dust samples from mattresses in homes without pets were significantly greater than in mattresses from homes with pets, reflecting the greater densities of D. pteronyssinus found in the former home category. Mite species richness was greater in homes with pets (17 species) than in homes without pets (13 species). This suggests that although the presence of pets can result in a wider variety of epidemiologically important mite species within households, increased competition among mite species may result in a more balanced mite fauna in the home, inhibiting the dominance of any one species and hence lowering allergen-associated risks. © 2015 The Royal Entomological Society.

Experimental infection of Salmonella Enteritidis by the poultry red mite, Dermanyssus gallinae.

PubMed

Valiente Moro, C; Chauve, C; Zenner, L

2007-05-31

Dermanyssus gallinae is an important ectoparasite of laying hens in Europe and it is suspected of being a vector of pathogens. We carried out an in vitro study to evaluate the role of D. gallinae as a vector of Salmonella enterica subsp. enterica serotype Enteritidis. Two means of infecting the mite were tested: through the blood meal and after cuticular contact. Mites became carriers of Salmonella immediately after the infection with 29% and 53%, respectively, for oral route and cuticular contact. This percentage increased over time until it reached 95% (D7) and 80% (D14). The numerical identification of bacteria on the selective medium SM ID demonstrated the multiplication of Salmonella inside previously infected mites. In addition, transovarial passage as well as transstadial passage (from N1 to N2 stages) were demonstrated. Moreover, the observation of a negative effect of Salmonella on Dermanyssus oviposition was also observed. Finally, previously infected mites were able to contaminate the blood during the blood meal. Therefore, it appears that D. gallinae may act as a biological vector of S. Enteritidis under experimental conditions. It may represent a suitable environment for the development of Salmonella and could be an additional factor for the persistence of salmonellosis infection between successive flocks.

Cleaner mites: sanitary mutualism in the miniature ecosystem of neotropical bee nests.

PubMed

Biani, Natalia B; Mueller, Ulrich G; Wcislo, William T

2009-06-01

Cleaning symbioses represent classic models of mutualism, and some bee mites are thought to perform cleaning services for their hosts in exchange for suitable environments for reproduction and dispersal. These mutual benefits, however, have not been rigorously demonstrated. We tested the sanitary role of bee mites by correlating mite loads with fungal contamination in natural nests of Megalopta genalis and Megalopta ecuadoria and by experimentally manipulating mite loads in artificial cells with developing brood. Field observations revealed significant correlations between the presence of mites and the absence of fungi inside the brood cells, as well as between the absence of mites and increased bee mortality. Likewise, experimental brood cells with mites have fewer fungal colonies than do cells without mites. Field observations and experimental manipulations, therefore, provide clear evidence of the sanitary effect of mites in nests of Megalopta bees. This bee-mite association constitutes one of the few examples of terrestrial cleaning mutualisms.

A preliminary study of the acaricidal activity of clove oil, Eugenia caryophyllus.

PubMed

Mahakittikun, Vanna; Soonthornchareonnon, Noppamas; Foongladda, Sooporn; Boitano, John Joseph; Wangapai, Teerapong; Ninsanit, Prapakorn

2014-03-01

The search for more eco-friendly acaricides has prompted testing of medicinal plants from botanical sources. To evaluate the eradication of house dust mites (HDM), Dermatophagoides pteronyssinus, by direct contact using the essential clove oil (Eugenia caryophyllus). A pilot study was initiated to determine the killing power of clove oil. Synthetic fibers were immersed in 2% clove oil for 30 min, dried in a hot air oven at 60°C for 2 hrs after which 0.5 gm of HDMs were exposed to these coated fibers placed in the Siriraj Chamber (SC). Two additional long-term methods were employed. Ten mites were placed in the SC and 10 μl of clove oil was pipetted or sprayed onto them. These latter two procedures were each carried out for 3 consecutive days at 0, 1, 3 and 6 months. The solutions antimicrobial and antifungal properties were evaluated by exposing common bacteria and fungi to sterile filter disks impregnated with the mixture, and after overnight incubation, the disc diffusion method on nutrient agar was used. Ethyl alcohol served as the placebo. 99% and 81%, respectively, while the placebo mortality was <5%. The zone of inhibition indicated significant clearance for all the bacteria and fungi indicating greater biocidal activity when compared to the controls. SEMs revealed dead mites on the fibers. The effectiveness of pipetting and spraying was 99% and 81%, respectively, while the placebo mortality was <5%. The zone of inhibition indicated significant clearance for all the bacteria and fungi indicating greater biocidal activity when compared to the controls. Clove oil is a promising agent for killing dust mites with a potential use in dust-mite laden mattresses. Spraying diminishes in efficiency after 3 months.

Inefficacy of alcohol-based hand rub on mites in a patient with hyperkeratotic scabies.

PubMed

Cinotti, E; Perrot, J L; Labeille, B; Maguet, H; Couzan, C; Flori, P; Cambazard, F

2015-03-01

The World Health Organization is strongly promoting alcohol-based hand rubs to interrupt transmission of pathogens within the healthcare environment, and in some hospitals they are being recommended in cases of scabies. However, there are no studies that demonstrate the efficacy of such hand rubs against scabies. To evaluate the viability of Sarcoptes scabiei after the application of various topical antiseptics used for hand hygiene, and the effect of hand washing on the number of parasites present on the skin surface of a patient with scabies. We applied three different topical antiseptics (two alcohol-based and one povidone-iodine-based) to the skin of one hand that was affected by scabies, and took a skin scraping of each area to evaluate the viability of the mites over time. A skin scraping of a control area without antiseptic application was also taken. We also tested the antiseptics directly on the mites. Statistical comparison between the percentages of vital mites in the different samples was assessed using the χ(2) test. We also captured a dermoscopic image of the other hand before and after hand washing to count the number of parasites on the skin surface. Topical antiseptics did not reduce the number of living mites compared with control skin, and hand washing did not reduce the number of parasites on the skin surface. Application of topical antiseptics does not reduce the viability of S. scabiei, and is therefore unable to prevent the transmission of scabies. The usefulness of hand washing in preventing transmission of scabies to new subjects remains to be investigated. © 2014 British Association of Dermatologists.

An Ecoinformatics Approach to Field-Scale Evaluation of Insecticide Effects in California Citrus: Are Citrus Thrips and Citrus Red Mite Induced Pests?

PubMed

Livingston, George; Hack, Lindsey; Steinmann, Kimberly P; Grafton-Cardwell, Elizabeth E; Rosenheim, Jay A

2018-05-28

Experimental approaches to studying the consequences of pesticide use, including impacts on beneficial insects, are vital; however, they can be limited in scale and realism. We show that an ecoinformatics approach that leverages existing data on pesticides, pests, and beneficials across multiple fields can provide complementary insights. We do this using a multi-year dataset (2002-2013) on pesticide applications and density estimates of two pests, citrus thrips (Scirtothrips citri (Moulton [Thysanoptera: Thripidae])) and citrus red mites (Panonychus citri McGregor [Acari: Tetranychidae]), and a natural enemy (Euseius spp. predatory mites) collected from citrus groves in the San Joaquin Valley of California. Using correlative analyses, we investigated the long-term consequences of pesticide use on S. citri and P. citri population densities to evaluate the hypothesis that the pest status of these species is largely due to the disruption of natural biological control-i.e., these are induced pests. We also evaluated short-term pesticide efficacy (suppression of citrus thrips and citrus red mite populations immediately post-application) and asked if it was correlated with the suppression of Euseius predator populations. Although the short-term efficacy of different pesticides varied significantly, our dataset does not suggest that the use of citrus pesticides suppressed Euseius densities or worsened pest problems. We also find that there is no general trade-off between pesticide efficacy and pesticide risk to Eusieus, such that highly effective and minimally disruptive compounds were available to citrus growers during the studied time period.

Pesticides used against Cydia pomonella disrupt biological control of secondary pests of apple

USDA-ARS?s Scientific Manuscript database

The effects of codling moth management programs on secondary pests of apple were examined from 2008 to 2011 in five replicated large-plot trials. The orchards were chosen for a history of Eriosoma lanigerum and tetranychid mite outbreaks. Programs covered the first, second, or both generations of C....

Chemotherapeutic treatment of naturally acquired generalized demodicosis.

PubMed

Folz, S D; Kratzer, D D; Conklin, R D; Nowakowski, L H; Kakuk, T J; Rector, D L

1983-08-01

Fifty-two dogs naturally parasitized with Demodex canis and having the generalized form of the disease were utilized to evaluate the efficacy and safety of single or multiple topical treatments with a liquid concentrate formulation of amitraz. Ten dogs (5 treated, 5 controls) were utilized to evaluate a single treatment. A single topical treatment with the miticide did not significantly reduce the incidence of dogs with mites, however, significant clinical improvement resulted. Side-effects were not observed after treatment. Forty-two dogs (26 treated, 16 controls) were utilized to evaluate multiple topical treatments with the liquid concentrate. A series of 3-6 treatments was applied topically at 14-day intervals. The dogs treated with the miticide received an average of 4.5 topical treatments. All (100%) of the dogs responded clinically, and the mean rate of improvement at four weeks post-treatment was 99.1%. Most dogs (96.2%) were cleared of mites after 3-6 treatments, and Mitaban did not cause any dermatologic, ocular, or other clinical side-effects. Multiple treatments with the liquid concentrate were highly efficacious and safe for treatment of generalized demodicosis. Control dogs did not improve clinically and retained mite populations.

Combined evaluation of commonly used techniques, including PCR, for diagnosis of mouse fur mites.

PubMed

Karlsson, Eleanor M; Pearson, Laura M; Kuzma, Kristen M; Burkholder, Tanya H

2014-01-01

Our study evaluated and compared the false-negative rates (FNR) of a wide array of fur-mite diagnostic tests, including 2 postmortem tests (pelt exam and sticky paper) and 3 antemortem tests (adhesive tape, fur pluck, and PCR). Past publications examining fur-mite diagnostic techniques primarily used paired comparisons, evaluating tests by their level of agreement with only one other test. However, different combinations or pairs of diagnostics are used in the different studies, making the results of these comparisons difficult to interpret across all available diagnostics. In the current study, mice from a conventionally maintained colony endemic for Myobia musculi were identified as positive based on at least one positive diagnostic test. From this pool of positive animals, the FNR of all tests were quantified. The PCR assay and the pelt exam performed the best, with 0% and 2% FNR respectively, whereas tape, fur-pluck, and sticky-paper tests showed 24%, 26%, and 36% FNR, respectively. Our study shows that for mice in a colony naturally infested with Myobia musculi, PCR testing can be used for reliable antemortem detection, and pelt exam performed by experienced examiners is reliable for postmortem detection.

Sensitization to house dust mites in Reykjavik, Iceland, in the absence of domestic exposure to mites.

PubMed

Hallas, T E; Gislason, D; Björnsdottir, U S; Jörundsdottir, K B; Janson, C; Luczynska, C M; Gislason, T

2004-05-01

House dust mites are common sources of indoor allergens. In Reykjavik, Iceland, 9% of the young adult population had serum-specific IgE to Dermatophagoides pteronyssinus. Sensitization to mites is usually assumed to be due to exposure to house dust mites in the indoor environment. This investigation was carried out to measure the concentrations of house dust mite allergens and to investigate which species of mites were present in beds in Iceland. A total of 197 randomly selected adults were visited at home using the European Community Respiratory Health Survey (ECRHS) II Indoor protocol. Dust samples were collected from mattresses for measurement of house dust mite allergen concentrations and to estimate the number and type of house dust mites. Additional samples from mattresses and floors were collected from the homes of 10 patients with positive skin prick tests (SPT) to D. pteronyssinus. House dust mite allergen concentrations were measured using ELISA and examination of mite species was carried out using microscopy. Climatic parameters were assessed using psychrometer readings in the bedrooms and outdoors. We found two single mite specimens, both D. pteronyssinus, in two dust samples. Mite allergen analyses indicated that two other dust samples had Der f 1 results close to the cut-off of 0.1 microg/g of dust. No samples were positive for Der p 1. In an additional collection of dust from the homes of 10 SPT-positive patients no Dermatophagoides spp. were found. Reykjavik citizens are exposed to extremely low amounts of house dust mite allergens in their homes. Possible alternative sources for sensitization are discussed, such as bird nests, exposure from travelling abroad, or other mites or invertebrates that cross-react with house dust mite allergens. Our findings suggest that exposures other than to house dust mites indoors are possible sources of mite allergen exposure.

Resistance to Arrenurus spp. Parasitism in Odonates: Patterns Across Species and Comparisons Between a Resistant and Susceptible Host

PubMed Central

Worthen, Wade B.

2016-01-01

Some adult odonates resist parasitism by larval water mites (Arrenurus spp.) with melanotic encapsulation, in which the mite’s stylestome is clogged and the mite starves. In summer 2014, we counted the engorged and resisted mites on 2,729 adult odonates sampled by aerial net at 11 water bodies in Greenville Co. and Pickens Co., SC, and tested the hypothesis that the frequency and intensity of resistance correlates with parasite prevalence (the percentage of parasitized hosts). Resistance prevalence (the percentage of parasitized hosts that resisted at least one mite) varied significantly among host species, exceeding 60% for Argia fumipennis (Burmeister) and Celithemis fasciata Kirby but less than 20% for other species. However, neither resistance prevalence nor mean resistance intensity (mean percentage of resisted mites on resisting hosts) correlated with parasite prevalence. We described potential effects of parasitism on host development of A. fumipennis and Pachydiplax longipennis (Burmeister) by comparing the percent asymmetry of forewing lengths between parasitized and unparasitized individuals. There was no significant difference in asymmetry for either males or females of A. fumipennis, or males of Pa. longipennis (females were not sampled). We also evaluated differences in melanotic encapsulation between A. fumipennis, which readily encapsulates mites in nature, and Pa. longipennis. We inserted a 2.0-mm piece of sterile monofilament line into the thorax of captured individuals for 24 h and compared mean gray value scores of inserted and emergent ends using Image-J software. There was no difference in melanotic encapsulation between species. PMID:27067302

Induction of direct and indirect plant responses by jasmonic acid, low spider mite densities, or a combination of jasmonic acid treatment and spider mite infestation.

PubMed

Gols, Rieta; Roosjen, Mara; Dijkman, Herman; Dicke, Marcel

2003-12-01

Jasmonic acid (JA) and the octadecanoid pathway are involved in both induced direct and induced indirect plant responses. In this study, the herbivorous mite, Tetranychus urticae, and its predator, Phytoseiulus persimilis, were given a choice between Lima bean plants induced by JA or spider mites and uninduced control plants. Infestation densities resulting in the induction of predator attractants were much lower than thus far assumed, i.e., predatory mites were significantly attracted to plants that were infested for 2 days with only one or four spider mites per plant. Phytoseiulus persimilis showed a density-dependent response to volatiles from plants that were infested with different numbers of spider mites. Similarly, treating plants with increasing concentrations of JA also led to increased attraction of P. persimilis. Moreover, the duration of spider mite infestation was positively correlated with the proportion of predators that were attracted to mite-infested plants. A pretreatment of the plants with JA followed by a spider mite infestation enhanced the attraction of P. persimilis to plant volatiles compared to attraction to volatiles from plants that were only infested with spider mites and did not receive a pretreatment with JA. The herbivore, T. urticae preferred leaf tissue that previously had been infested with conspecifics to uninfested leaf tissue. In the case of choice tests with JA-induced and control leaf tissue, spider mites slightly preferred control leaf tissue. When spider mites were given a choice between leaf discs induced by JA and leaf discs damaged by spider mite feeding, they preferred the latter. The presence of herbivore induced chemicals and/or spider mite products enhanced settlement of the mites, whereas treatment with JA seemed to impede settlement.

Influence of spatio-temporal resource availability on mushroom mite diversity.

PubMed

Okabe, Kimiko

2013-11-01

Although biodiversity in nature is of fundamental importance because it improves the sustainability of ecosystems, communities of microscopic organisms are generally excluded from conservation targets for biodiversity. Here, I hypothesize that mushroom mite species richness is correlated with both spatial (i.e., mushroom size) and temporal (i.e., longevity of fruiting bodies) resource availability. I collected fruiting bodies in an old-growth forest over 4 years to collect mites and insects inhabiting the mushrooms. Mites were collected from 47 % of the fruiting bodies and approximately 60 % of the mite species were collected only once. Mite species richness was significantly correlated with the availability of long-lasting fruiting bodies. For example, bracket fungi contained more mite species than ephemeral fruiting bodies. Insect presence was also correlated with mushroom mite richness, probably as phoretic hosts and food resources for predacious mites. On the other hand, mushroom size seemed to be less important; small fruiting bodies sometimes harbored several mite species. Although mite species richness was correlated with mushroom species richness, mushroom specificity by mites was not clear except for a preference for long-lasting fruiting bodies. Therefore, I suggest that a constant supply of coarse woody debris is crucial for maintaining preferred resources for mushroom mites (e.g., bracket fungi) and their associated insects (mycophilous and possibly saproxylic insects).

Attraction of Phytoseiulus persimilis (Acari: Phytoseiidae) towards volatiles from various Tetranychus urticae-infested plant species.

PubMed

van den Boom, C E M; van Beek, T A; Dicke, M

2002-12-01

Plants infested with the spider mite Tetranychus urticae Koch, may indirectly defend themselves by releasing volatiles that attract the predatory mite Phytoseiulus persimilis Athias-Henriot. Several plants from different plant families that varied in the level of spider mite acceptance were tested in an olfactometer. The predatory mites were significantly attracted to the spider mite-infested leaves of all test plant species. No differences in attractiveness of the infested plant leaves were found for predatory mites reared on spider mites on the different test plants or on lima bean. Thus, experience with the spider mite-induced plant volatiles did not affect the predatory mites. Jasmonic acid was applied to ginkgo leaves to induce a mimic of a spider mite-induced volatile blend, because the spider mites did not survive when incubated on ginkgo. The volatile blend induced in ginkgo by jasmonic acid was slightly attractive to predatory mites. Plants with a high degree of direct defence were thought to invest less in indirect defence than plants with a low degree of direct defence. However, plants that had a strong direct defence such as ginkgo and sweet pepper, did emit induced volatiles that attracted the predatory mite. This indicates that a combination of direct and indirect defence is to some extent compatible in plant species.

[Active miniature inverted-repeat transposable elements transposon in plants: a review].

PubMed

Hu, Bingjie; Zhou, Mingbing

2018-02-25

Miniature inverted-repeat transposable elements transposon is a special transposon that could transpose by "cut-paste" mechanism, which is one of characteristics of DNA transposons. Otherwise, the copy number of MITEs is very high, which is one of characteristics of RNA transposons. Many MITE families have been reported, but little about active MITEs. We summarize recent advances in studying active MITEs. Most the MITEs belong to the Tourist-like family, such as mPing, mGing, PhTourist1, Tmi1 and PhTst-3. Additionally, DTstu1 and MITE-39 belong to Stowaway-like family, and AhMITEs1 belongs to Mutator-like family. Moreover, we summarize the structure (terminal inverse repeats and target site duplications), copy number, evolution pattern and transposition characteristics of these active MITEs, to provide the foundation for the identification of other active MITEs and subsequent research on MITE transposition and amplification mechanism.

ST. LOUIS ENCEPHALITIS

PubMed Central

Smith, Margaret G.; Blattner, Russell J.; Heys, Florence M.

1946-01-01

A colony of chicken mites (Dermanyssus gallinae) was established from a single adult female mite and her offspring. This colony of mites was shown to be free of the virus of St. Louis encephalitis. Infection of mites from this homogeneous colony with the virus of St. Louis encephalitis was accomplished by feeding on chickens having viremia. The virus was recovered as readily from mites which had not been allowed to feed for 8 days as from mites freshly engorged, showing that the demonstration of virus in the mites does not depend on the presence of fresh infective chicken blood. Transovarian passage of the St. Louis virus into the second generation has been demonstrated in mites infected experimentally. The female mite infected as an adult can pass the St. Louis virus through eggs laid after additional feeding on normal blood. Persistence of the virus for a period of 6 months has been shown in a colony of mites infected experimentally in the laboratory. PMID:19871548

Antixenosis and antibiosis response of common bean (Phaseolus vulgaris) to two-spotted spider mite (Tetranychus urticae).

PubMed

Shoorooei, Marie; Hoseinzadeh, Abdul Hadi; Maali-Amiri, Reza; Allahyari, Hossein; Torkzadeh-Mahani, Masoud

2018-04-01

The two-spotted spider mite, Tetranychus uticae Koch (Acari: Tetranychidae), is globally one of the most devastating pests that feed on numerous crops, including common bean (Phaseolus vulgaris L.). This study was aimed to evaluate the effects of genotype and morphological attributes of common bean on T. uticae. Forty common bean accessions were used to investigate antixenosis and antibiosis through assessing mite feeding preference and reproduction under laboratory conditions. Three resistant (i.e., 56, 63, 238) and two susceptible (i.e., 182, 236) accessions, along with cultivars Naz (resistant) and Akhtar (susceptible), were used in a life-table study. Both antixenosis and antibiosis mechanism were observed in all of the accessions, albeit a negative correlation occurred. Significant differences were observed for all traits of T. urticae: developmental time of immature stages, reproduction, adult longevity and life-table parameters. Based on the intrinsic rate of increase, the accessions 56, 63, 182, 238, and cv. Naz impose high antibiotic effects on T. urticae. Although significant variation existed among accessions for morphological factors, only glandular trichomes correlated with mite fecundity and feeding preference.

In vitro efficacies of oils, silicas and plant preparations against the poultry red mite Dermanyssus gallinae.

PubMed

Maurer, Veronika; Perler, Erika; Heckendorn, Felix

2009-06-01

The aim of this study was to test the effectiveness of physically acting substances (oils and silicas) and plant preparations for the control of the poultry red mite Dermanyssus gallinae (De Geer 1778). Reproduction and survival of fed D. gallinae females were evaluated in vitro for a total of 168 h using the "area under the survival curve" (AUC) to compare survival of the mites between treatments. Four oils (two plant oils, one petroleum spray oil and diesel), one soap, three silicas (one synthetic amorphous silica, one diatomaceous earth (DE) and one DE with 2% pyrethrum extract) and seven plant preparations (derived from Chrysanthemum cineariaefolium, Allium sativum, Tanacetum vulgare, Yucca schidigera, Quillaja saponaria, Dryopteris filix-mas, and Thuja occidentalis) were tested at various concentrations. All the oils, diesel and soap significantly reduced D. gallinae survival. All silicas tested inhibited reproduction. DE significantly reduced mite survival, but amorphous silica was less effective in vitro. Except for pure A. sativum juice and the highest concentration of C. cineariaefolium extract, the plant preparations tested resulted in statistically insignificant control of D. gallinae.

Non-phytoseiid Mesostigmata within citrus orchards in Florida: species distribution, relative and seasonal abundance within trees, associated vines and ground cover plants and additional collection records of mites in citrus orchards.

PubMed

Childers, Carl C; Ueckermann, Eduard A

2015-03-01

Seven citrus orchards on reduced- to no-pesticide spray programs in central and south central Florida were sampled for non-phytoseiid mesostigmatid mites. Inner and outer canopy leaves, fruits, twigs and trunk scrapings were sampled monthly between August 1994 and January 1996. Open flowers were sampled in March from five of the sites. A total of 431 samples from one or more of 82 vine or ground cover plants were sampled monthly in five of the seven orchards. Two of the seven orchards (Mixon I and II) were on full herbicide programs and vines and ground cover plants were absent. A total of 2,655 mites (26 species) within the families: Ascidae, Blattisociidae, Laelapidae, Macrochelidae, Melicharidae, Pachylaelapidae and Parasitidae were identified. A total of 685 mites in the genus Asca (nine species: family Ascidae) were collected from within tree samples, 79 from vine or ground cover plants. Six species of Blattisociidae were collected: Aceodromus convolvuli, Blattisocius dentriticus, B. keegani, Cheiroseius sp. near jamaicensis, Lasioseius athiashenriotae and L. dentatus. A total of 485 Blattisociidae were collected from within tree samples compared with 167 from vine or ground cover plants. Low numbers of Laelapidae and Macrochelidae were collected from within tree samples. One Zygoseius furciger (Pachylaelapidae) was collected from Eleusine indica. Four species of Melicharidae were identified from 34 mites collected from within tree samples and 1,190 from vine or ground cover plants: Proctolaelaps lobatus was the most abundant species with 1,177 specimens collected from seven ground cover plants. One Phorytocarpais fimetorum (Parasitidae) was collected from inner leaves and four from twigs. Species of Ascidae, Blattisociidae, Melicharidae, Laelapidae and Pachylaelapidae were collected from 31 of the 82 vine or ground cover plants sampled, representing only a small fraction of the total number of Phytoseiidae collected from the same plants. Including the collection records of Martin Muma prior to 1975, a total of 69 species of Ascidae, Blattisociidae, Laelapidae, Macrochelidae, Melicharidae, Pachylaelapidae and Parasitidae have now been reported from citrus in Florida.

House dust mites, our intimate associates.

PubMed

Nadchatram, M

2005-06-01

House dust mites have lived in human contact from time immemorial. Human dander or dead skin constitutes the major organic component of the house dust ecosystem. Because the mites feed on dander, dust mites and human association will continue to co-exist as part of our environment. Efficient house-keeping practice is the best form of control to reduce infestation. However, special precautions are important when individuals are susceptible or sensitive to dust mites. House dust mites are responsible for causing asthma, rhinitis and contact dermatitis. The respiratory allergies are caused by the inhalation of dead or live mites, their faecal matter or other byproducts. Immune factors are of paramount importance in the development of dust related or mite induced respiratory diseases. House dust mites were found in some 1,000 samples of dust taken from approximately 330 dwellings in Peninsular Malaysia and Singapore. Mattresses, carpets, corners of a bedroom, and floor beneath the bed are favourable dust mite habitats. The incriminating species based on studies here and elsewhere, as well as many other species of dust mites of unknown etiological importance are widely distributed in Malaysian homes. Density of dust mites in Malaysia and Singapore is greater than in temperate countries. Prevention and control measures with reference to subjects sensitive to dust mite allergies, including chemical control described in studies conducted in Europe and America are discussed. However, a cost free and most practical way to remove mites, their faecal matter and other products is to resort to sunning the bedding and carpets to kill the living mites, and then beaten and brushed to remove the dust and other components.

MITEE-B: A Compact Ultra Lightweight Bi-Modal Nuclear Propulsion Engine for Robotic Planetary Science Missions

NASA Astrophysics Data System (ADS)

Powell, James; Maise, George; Paniagua, John; Borowski, Stanley

2003-01-01

Nuclear thermal propulsion (NTP) enables unique new robotic planetary science missions that are impossible with chemical or nuclear electric propulsion systems. A compact and ultra lightweight bi-modal nuclear engine, termed MITEE-B (MInature ReacTor EnginE - Bi-Modal) can deliver 1000's of kilograms of propulsive thrust when it operates in the NTP mode, and many kilowatts of continuous electric power when it operates in the electric generation mode. The high propulsive thrust NTP mode enables spacecraft to land and takeoff from the surface of a planet or moon, to hop to multiple widely separated sites on the surface, and virtually unlimited flight in planetary atmospheres. The continuous electric generation mode enables a spacecraft to replenish its propellant by processing in-situ resources, provide power for controls, instruments, and communications while in space and on the surface, and operate electric propulsion units. Six examples of unique and important missions enabled by the MITEE-B engine are described, including: (1) Pluto lander and sample return; (2) Europa lander and ocean explorer; (3) Mars Hopper; (4) Jupiter atmospheric flyer; (5) SunBurn hypervelocity spacecraft; and (6) He3 mining from Uranus. Many additional important missions are enabled by MITEE-B. A strong technology base for MITEE-B already exists. With a vigorous development program, it could be ready for initial robotic science and exploration missions by 2010 AD. Potential mission benefits include much shorter in-space times, reduced IMLEO requirements, and replenishment of supplies from in-situ resources.

Eco-friendly control of the poultry red mite, Dermanyssus gallinae (Dermanyssidae), using the α-thujone-rich essential oil of Artemisia sieberi (Asteraceae): toxic and repellent potential.

PubMed

Tabari, Mohaddeseh Abouhosseini; Youssefi, Mohammad Reza; Benelli, Giovanni

2017-05-01

The poultry red mite, Dermanyssus gallinae, represents a key threat for the poultry industry worldwide. The control of D. gallinae is mainly achieved by continuous applications of acaricides. However, the fast-growing development of resistance, and the strict laws concerning chemicals admitted for treatments on food animals, highlighted the importance of alternative control tools. Here, we explored the potential of Artemisia sieberi essential oil against D. gallinae. In this study, the A. sieberi essential oil was analyzed using GC and GC-MS. The oil toxicity through contact and fumigant assays on adult mites was evaluated. The oil repellent activity was assessed on adult mites over different time intervals. Lastly, the residual toxicity of various doses of the oil was evaluated on D. gallinae until 14 days post treatment. GC and GC-MS showed that the oil was rich in α-thujone (31.5%), β-thujone (11.92%), camphor (12.3%), and 1,8-cineole (10.09%). Contact toxicity on adult mites showed 50% lethal concentration (LC 50 ), LC 90 , and LC 99 of 15.85, 26.63, and 35.42 μg/cm 3 , respectively. In fumigant assays, the oil was toxic on D. gallinae, and mortality was significantly higher in open containers over closed ones, underlining the key role of highly volatile constituents. Repellent assays showed that after 24 h from the treatment, all doses of the A. sieberi essential oil led to significant repellent activity over the control, except for 2 μg/cm 3 . After 48 h, A. sieberi essential oil tested at all doses led to significant repellent activity, if compared to the control. Residual toxicity assays showed that time exposure and concentration tested had a significant impact on mite mortality after 1, 2, 5, and 7 days from the treatment. Notably, mortality remained significantly higher over the control for 7 days after spraying with oil at 2%. Further field assays with selected molecules from the A. sieberi essential oil are ongoing, testing them in synergistic blends, as well as in microencapsulated formulations.

[Investigation of Acaroid mites breeding in stored dry fruits].

PubMed

Tao, Ning; Zhan, Xiao-dong; Sun, En-tao; Li, Chao-pin

2015-12-01

To study the species and density of Acaroid mites breeding in stored dry fruits. The samples from the dried fruit stores and warehouses were collected, and the mites breeding in them were separated, then the slides with mites were prepared and observed by a light microscope for species identification and counting. The indexes such as the breeding density, species richness index, diversity index and evenness index were calculated. Totally 12 species of Acaroid mites belonging to 6 families and 10 genera were obtained from the total 49 samples. The dominant mite species were Carpoglyphus lactis, Tyrophagus putrescentiae, Acarus siro, and Caloglyphus berlesei. The breeding densities of mites in longans, filberts and plum candies were 79.78, 48.91, 35.73 mites/g, respectively, which were higher than those in other dry fruits. The seasonal variation experiment of mites found that the average breeding density of acaroid mites was higher in July and October, the richness index and diversity index reached the highest value in July, and the evenness index was higher in January and April. The observation of the growth and decline of Acaroid mites under the artificial condition found the number of Caloglyphus berlesei declined sharply and Tyrophagus putrescentiae first increased and then decreased. The pollution of Acaroid mites is serious in the stored dried fruits, for which the positive prevention and control measures to the mite breeding should be taken to reduce the harm.

Oral mite anaphylaxis caused by mite-contaminated okonomiyaki/ pancake-mix in Japan: 8 case reports and a review of 28 reported cases.

PubMed

Takahashi, Kentaro; Taniguchi, Masami; Fukutomi, Yuma; Sekiya, Kiyoshi; Watai, Kentaro; Mitsui, Chihiro; Tanimoto, Hidenori; Oshikata, Chiyako; Tsuburai, Takahiro; Tsurikisawa, Naomi; Minoguchi, Kenji; Nakajima, Hiroshi; Akiyama, Kazuo

2014-03-01

Anaphylaxis after the ingestion of foods contaminated with mites has recently been recognized. Case series and case reports thus far have shown that mite-contaminated wheat flour is the major cause of oral mite anaphylaxis. However, we have found 8 cases of oral mite anaphylaxis which were caused by mite-contaminated okonomiyaki-mix, a savory Japanese style pancake mix, in our hospital. In addition to our 8 cases, the databases of MEDLINE and ICHUSHI were systematically searched for patients with oral mite anaphylaxis in Japan. Thirty-six patients including our 8 cases with oral mite anaphylaxis were identified. Thirty-four out of 36 cases (94%) ingested okonomiyaki or takoyaki, prepared at home using okonomiyaki-mix or takoyaki-mix which was previously opened and stored for months at ambient temperature. Microscopic examination of culprit mixes of 16 cases including our 1 case revealed contamination of mites such as Dermatophagoides farina (Der f) (5 cases), Tyrophagus putrescentiae (Tyr p) (4 cases), and Dermatophagoides pteronyssinus (Der p) (3 cases). The specific IgE to each mite is generally upregulated in these patients. Especially, the titers of specific IgE to Der p and Der f were more than class 2 in all cases. Mite-contaminated flavored flour is the major cause of oral mite anaphylaxis in Japan.

Oral Mite Anaphylaxis Caused by Mite-Contaminated Okonomiyaki/Pancake-Mix in Japan: 8 Case Reports and a Review of 28 Reported Cases.

PubMed

Takahashi, Kentaro; Taniguchi, Masami; Fukutomi, Yuma; Sekiya, Kiyoshi; Watai, Kentaro; Mitsui, Chihiro; Tanimoto, Hidenori; Oshikata, Chiyako; Tsuburai, Takahiro; Tsurikisawa, Naomi; Minoguchi, Kenji; Nakajima, Hiroshi; Akiyama, Kazuo

2013-12-25

Background: Anaphylaxis after the ingestion of foods contaminated with mites has recently been recognized. Case series and case reports thus far have shown that mite-contaminated wheat flour is the major cause of oral mite anaphylaxis. However, we have found 8 cases of oral mite anaphylaxis which were caused by mite-contaminated okonomiyaki-mix, a savory Japanese style pancake mix, in our hospital. Methods: In addition to our 8 cases, the databases of MEDLINE and ICHUSHI were systematically searched for patients with oral mite anaphylaxis in Japan. Results: Thirty-six patients including our 8 cases with oral mite anaphylaxis were identified. Thirty-four out of 36 cases (94%) ingested okonomiyaki or takoyaki, prepared at home using okonomiyaki-mix or takoyaki-mix which was previously opened and stored for months at ambient temperature. Microscopic examination of culprit mixes of 16 cases including our 1 case revealed contamination of mites such as Dermatophagoides farina (Der f) (5 cases), Tyrophagus putrescentiae (Tyr p) (4 cases), and Dermatophagoides pteronyssinus (Der p) (3 cases). The specific IgE to each mite is generally upregulated in these patients. Especially, the titers of specific IgE to Der p and Der f were more than class 2 in all cases. Conclusions: Mite-contaminated flavored flour is the major cause of oral mite anaphylaxis in Japan.

Toxicity of vegetable oils to the coconut mite Aceria guerreronis and selectivity against the predator Neoseiulus baraki.

PubMed

Oliveira, Natália N F C; Galvão, Andreia S; Amaral, Ester A; Santos, Auderes W O; Sena-Filho, José G; Oliveira, Eugenio E; Teodoro, Adenir V

2017-05-01

The coconut mite, Aceria guerreronis (Acari: Eriophyidae), is a major tropical pest of coconut. Here, we assessed the chemical profiles and the potential use of babassu, degummed soybean, and coconut oils to control A. guerreronis as well as their side-effects on the predatory mite Neoseiulus baraki (Acari: Phytoseiidae), a key natural enemy of the coconut mite. Babassu and coconut oils had similar fatty acids chemical profiles. All vegetable oils showed toxicity to A. guerreronis; degummed soybean oil exhibited the highest toxicity (LC 50  = 0.15 µL/cm 2 ). Although all oils were less toxic to N. baraki, their potential to attract/repel this predatory mite differed. Whereas N. baraki females were unresponsive to coconut oil at both concentrations (i.e., LC 50 and LC 99 estimated for A. guerreronis), irrespective of exposure period (i.e., 1 or 24 h), the babassu oil repelled the predator, independent of exposure period, when applied at its LC 99 (1.48 µL/cm 2 ). Intriguingly, this oil also exhibited attractiveness to N. baraki 24 h after exposure when applied at its LC 50 (0.26 µL/cm 2 ). A similar attractiveness pattern was recorded 24 h after N. baraki was exposed to degummed soybean oil at both concentrations tested (LC 50  = 0.15 µL/cm 2 ; LC 99  = 1.39 µL/cm 2 ). However, N. baraki was repelled by degummed soybean oil at its LC 50 after 1 h of exposure. Therefore, the present study demonstrated that all the vegetable oils used here had higher toxicity to the coconut mite and considerable selectivity to the predator N. baraki, indicating they are promising tools that can potentially be included in management programs to control A. guerreronis in commercial coconut plantations.

Phytoseiid mites from tropical fruit trees in Bahia State, Brazil (Acari, Phytoseiidae)

PubMed Central

de Souza, Izabel Vieira; Sá Argolo, Poliane; Júnior, Manoel Guedes Correa Gondim; de Moraes, Gilberto José; Bittencourt, Maria Aparecida Leão; Oliveira, Anibal Ramadan

2015-01-01

Abstract The cultivation of tropical fruit trees has grown considerably in the state of Bahia, northeastern Brazil. Some of these have been severely attacked by phytophagous mites, which are usually controlled by the use of chemical pesticides. However, there is today a growing interest for the adoption of less aggressive measures of pest control, as for example the use of predatory mites. Most of the plant-inhabiting predatory mites belong to the family Phytoseiidae. The objective of this paper is to report the phytoseiid species found in an intensive survey conducted on cultivated tropical fruit trees in fifteen localities of the southern coast of Bahia. Measurements of relevant morphological characters are provided for each species, to complement the understanding of the morphological variation of these species. Twenty-nine species of sixteen genera were identified. A key was elaborated to assist in the separation of these species. Fifteen species are reported for the first time in the state, raising to sixty-six the number of species of this family now known from Bahia. Seventy-two percent of the species collected belong to Amblyseiinae, followed by Typhlodrominae (21%) and Phytoseiinae (7%). The most diverse genus was Amblyseius. Amblyseius operculatus De Leon was the most frequent and abundant species. Studies should be conducted to evaluate the possible role of the most common predators as control agents of the phytophagous mites co-occurring with them. PMID:26668542

Linking pollen quality and performance of Neoseiulus californicus (Acari: Phytoseiidae) in two-spotted spider mite management programmes.

PubMed

Khanamani, Mostafa; Fathipour, Yaghoub; Talebi, Ali Asghar; Mehrabadi, Mohammad

2017-02-01

It has been shown that pollen as a dietary supplement may increase the establishment of generalist predatory mites, and therefore pest control by these mites can be provided. Life table studies were performed to evaluate the nutritional value of seven different pollens (almond, castor-bean, date-palm, maize, bitter-orange, sunflower and mixed bee pollen) as a supplementary food source for the spider mite predator Neoseiulus californicus McGregor. In addition, the nutritional quality of each pollen species was assessed through morphological and chemical analysis. Preadult duration was longer when the predator fed on castor-bean pollen (10.01 days) and bee pollen (9.94 days) compared with the others (5.58-7.27 days). The cohort reared on almond pollen had the highest intrinsic rate of increase (r) (0.231 day -1 ), and those on mixed bee pollen had the lowest r (0.005 day -1 ). The levels of nutritional content (sugar, lipid and protein) were significantly different among tested pollens. Comparison of N. californicus life table parameters on different diets revealed that the almond pollen (and after that the maize pollen) was a more suitable diet than the others. These findings will be useful in developing appropriate strategies for conservation of N. californicus to control spider mites. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Tolerance to solar ultraviolet-B radiation in the citrus red mite, an upper surface user of host plant leaves.

PubMed

Fukaya, Midori; Uesugi, Ryuji; Ohashi, Hirokazu; Sakai, Yuta; Sudo, Masaaki; Kasai, Atsushi; Kishimoto, Hidenari; Osakabe, Masahiro

2013-01-01

Plant-dwelling mites are potentially exposed to solar ultraviolet-B (UVB) radiation that causes deleterious and often lethal effects, leading most mites to inhabit the lower (underside) leaf surfaces. However, in species of spider mite belonging to the Genus Panonychus, a substantial portion of individuals occur on upper leaf surfaces. We investigated whether the upper leaf surfaces of citrus trees are favorable for P. citri, and to what extent they are tolerant to UVB radiation. If eggs are not adequately protected from UVB damage, females may avoid ovipositing on the upper surfaces of sunny leaves. To test this, we conducted laboratory experiments using a UVB lamp, and semioutdoor manipulative experiments. As a result, P. citri eggs are tolerant to UVB. Field studies revealed that the ratio of eggs and adult females on upper leaf surfaces were larger for shaded than for sunny leaves. However, 64-89% of eggs hatched successfully even on sunny upper leaf surfaces. Nutritional evaluation revealed that whether on sunny or shaded leaves, in fecundity and juvenile development P. citri reaped the fitness benefits of upper leaf surfaces. Consequently, P. citri is tolerant to UVB damage, and inhabiting the upper surfaces of shaded leaves is advantageous to this mite. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.

Phytoseiid mites from tropical fruit trees in Bahia State, Brazil (Acari, Phytoseiidae).

PubMed

de Souza, Izabel Vieira; Sá Argolo, Poliane; Júnior, Manoel Guedes Correa Gondim; de Moraes, Gilberto José; Bittencourt, Maria Aparecida Leão; Oliveira, Anibal Ramadan

2015-01-01

The cultivation of tropical fruit trees has grown considerably in the state of Bahia, northeastern Brazil. Some of these have been severely attacked by phytophagous mites, which are usually controlled by the use of chemical pesticides. However, there is today a growing interest for the adoption of less aggressive measures of pest control, as for example the use of predatory mites. Most of the plant-inhabiting predatory mites belong to the family Phytoseiidae. The objective of this paper is to report the phytoseiid species found in an intensive survey conducted on cultivated tropical fruit trees in fifteen localities of the southern coast of Bahia. Measurements of relevant morphological characters are provided for each species, to complement the understanding of the morphological variation of these species. Twenty-nine species of sixteen genera were identified. A key was elaborated to assist in the separation of these species. Fifteen species are reported for the first time in the state, raising to sixty-six the number of species of this family now known from Bahia. Seventy-two percent of the species collected belong to Amblyseiinae, followed by Typhlodrominae (21%) and Phytoseiinae (7%). The most diverse genus was Amblyseius. Amblyseius operculatus De Leon was the most frequent and abundant species. Studies should be conducted to evaluate the possible role of the most common predators as control agents of the phytophagous mites co-occurring with them.

Genotypic variability and relationships between mite infestation levels, mite damage, grooming intensity, and removal of Varroa destructor mites in selected strains of worker honey bees (Apis mellifera L.).

PubMed

Guzman-Novoa, Ernesto; Emsen, Berna; Unger, Peter; Espinosa-Montaño, Laura G; Petukhova, Tatiana

2012-07-01

The objective of this study was to demonstrate genotypic variability and analyze the relationships between the infestation levels of the parasitic mite Varroa destructor in honey bee (Apis mellifera) colonies, the rate of damage of fallen mites, and the intensity with which bees of different genotypes groom themselves to remove mites from their bodies. Sets of paired genotypes that are presumably susceptible and resistant to the varroa mite were compared at the colony level for number of mites falling on sticky papers and for proportion of damaged mites. They were also compared at the individual level for intensity of grooming and mite removal success. Bees from the "resistant" colonies had lower mite population rates (up to 15 fold) and higher percentages of damaged mites (up to 9 fold) than bees from the "susceptible" genotypes. At the individual level, bees from the "resistant" genotypes performed significantly more instances of intense grooming (up to 4 fold), and a significantly higher number of mites were dislodged from the bees' bodies by intense grooming than by light grooming (up to 7 fold) in all genotypes. The odds of mite removal were high and significant for all "resistant" genotypes when compared with the "susceptible" genotypes. The results of this study strongly suggest that grooming behavior and the intensity with which bees perform it, is an important component in the resistance of some honey bee genotypes to the growth of varroa mite populations. The implications of these results are discussed. Copyright © 2012 Elsevier Inc. All rights reserved.

Association of childhood perennial allergic rhinitis with subclinical airflow limitation.

PubMed

Ciprandi, G; Capasso, M

2010-03-01

Allergic rhinitis (AR) is a relevant risk factor for the onset of asthma, and a close association exists between the nose and the bronchi. Recently, it has been evidenced that the duration of AR and mite allergy represent high risks for spirometric impairment in allergic adults. To evaluate a group of AR children, without bronchial symptoms, to investigate spirometric impairments. Two hundred children with moderate-severe AR were consecutively evaluated. Clinical examination, skin prick test, and spirometry were performed in all children. Thirty-one percent of the children had forced expiratory flow at 25% and 75% of the pulmonary volume (FEF25-75%)<80% of the predicted values and 11% had both forced expiratory volume in 1 s and FEF25-75%<80% of the predicted values. Rhinitis duration and sensitization to house dust mites were significantly associated with impaired values of these spirometric parameters. This study highlights the close link between the upper and the lower airways and the role of some risk factors, such as long duration and mite sensitization, as early prognostic markers of bronchial involvement in children with AR and perceiving nasal symptoms alone.

Population survey of phytoseiid mites and spider mites on peach leaves and wild plants in Japanese peach orchard.

PubMed

Wari, David; Yamashita, Jun; Kataoka, Yoko; Kohara, Yoko; Hinomoto, Norihide; Kishimoto, Hidenari; Toyoshima, Shingo; Sonoda, Shoji

2014-07-01

A population survey of phytoseiid mites and spider mites was conducted on peach leaves and wild plants in Japanese peach orchards having different pesticide practices. The phytoseiid mite species composition on peach leaves and wild plants, as estimated using quantitative sequencing, changed during the survey period. Moreover, it varied among study sites. The phytoseiid mite species compositions were similar between peach leaves and some wild plants, such as Veronica persica, Paederia foetida, Persicaria longiseta, and Oxalis corniculata with larger quantities of phytoseiid mites, especially after mid-summer. A PCR-based method to detect the ribosomal ITS sequences of Tetranychus kanzawai and Panonychus mori from phytoseiid mites was developed. Results showed that Euseius sojaensis (specialized pollen feeder/generalist predator) uses both spider mites as prey in the field.

Life cycle and reproduction of house-dust mites: environmental factors influencing mite populations.

PubMed

Hart, B J

1998-01-01

An understanding of the life cycle of house-dust mites, as well as environmental factors influencing mite populations, can be exploited in mite control. The most important limiting factor for house-dust-mite populations is air humidity. House-dust mites osmoregulate through the cuticle and therefore require a high ambient air humidity to prevent excessive water loss. In addition, the supracoxal glands actively take up ambient water vapour, and the protonynph stage of the life cycle is resistant to desiccation. Larger house-dust-mite populations are found when the absolute indoor air humidity is above 7 g/kg (45% relative humidity at 20 degrees C). Consequently, ventilation by air-conditioning systems is being developed as a means of control. A number of other aspects of the domestic environment are also being manipulated in an integrated approach to render the habitat less suitable for mites. The potential exists for developing models for house-dust mite populations, environmental characteristics, and the effects of various approaches to control.

Complete sequence analysis of 18S rDNA based on genomic DNA extraction from individual Demodex mites (Acari: Demodicidae).

PubMed

Zhao, Ya-E; Xu, Ji-Ru; Hu, Li; Wu, Li-Ping; Wang, Zheng-Hang

2012-05-01

The study for the first time attempted to accomplish 18S ribosomal DNA (rDNA) complete sequence amplification and analysis for three Demodex species (Demodex folliculorum, Demodex brevis and Demodex canis) based on gDNA extraction from individual mites. The mites were treated by DNA Release Additive and Hot Start II DNA Polymerase so as to promote mite disruption and increase PCR specificity. Determination of D. folliculorum gDNA showed that the gDNA yield reached the highest at 1 mite, tending to descend with the increase of mite number. The individual mite gDNA was successfully used for 18S rDNA fragment (about 900 bp) amplification examination. The alignments of 18S rDNA complete sequences of individual mite samples and those of pooled mite samples ( ≥ 1000mites/sample) showed over 97% identities for each species, indicating that the gDNA extracted from a single individual mite was as satisfactory as that from pooled mites for PCR amplification. Further pairwise sequence analyses showed that average divergence, genetic distance, transition/transversion or phylogenetic tree could not effectively identify the three Demodex species, largely due to the differentiation in the D. canis isolates. It can be concluded that the individual Demodex mite gDNA can satisfy the molecular study of Demodex. 18S rDNA complete sequence is suitable for interfamily identification in Cheyletoidea, but whether it is suitable for intrafamily identification cannot be confirmed until the ascertainment of the types of Demodex mites parasitizing in dogs. Copyright © 2012 Elsevier Inc. All rights reserved.

Scabies by Kenneth Mellanby.

PubMed

Jackson, Robert

2004-01-01

Epidemics of scabies are often associated with wars or other times of social upheaval. This was particularly evident during the Second World War when it was estimated that there were one to two million patients with scabies in Great Britain. This article reviews the work of the zoologist Kenneth Mellanby of England and evaluates his contribution to our knowledge of the diagnosis and treatment of scabies in the Second World War. Using humans, Mellanby studied the transmission and treatment of this disease. Among his contributions were knowledge of how many mites the average patient had, and where they were located. He clearly noted and described that the scabies rash was not limited to the location of the mites on the body; he attributed the rash in areas with no mites to "a true sensitization." He found that "fomites were not the major method of transmissions.

Host preference, population growth and injuries assessment of Polyphagotarsonemus latus (banks) (ACARI: Tarsonemidae) on Capsicum annuum L. Genotypes.

PubMed

Breda, M O; de Oliveira, J V; Esteves Filho, A B; Barbosa, D R S; de Santana, M F

2016-10-01

Despite the continued efforts on the search for different genotypes, Capsicum annuum (L.) is quite susceptible to attack by pest arthropods, especially the broad mite Polyphagotarsonemus latus Banks. Thus, the host preference, population growth and the injuries assessment of P. latus was studied on six C. annuum genotypes used in Brazil (Atlantis, California Wonder, Impact, Palloma, Rubia and Tendence). Host preference was accessed in choice tests, pairing the several genotypes, and the population growth was observed through non-choice tests in laboratory. The injuries assessments were evaluated in the greenhouse, comparing the injury level among the six genotypes. The results indicate that California Wonder and Palloma genotypes were more preferred by P. latus, and Impact and Tendence were less preferred. P. latus presented positive population growth rates (ri) on all the genotypes, however, Palloma and California Wonder showed the highest values of population growth rate (ri = 0.344 and ri = 0.340, respectively), while Impact had the lowest value (ri = 0.281). All the evaluated C. annuum genotypes showed low tolerance to P. latus and exhibited several injuries, but there was no statistical difference between them. California Wonder had the highest average number of mites/leaf (57.15), while Impact and Tendence obtained the lowest values (36.67 and 35.12, respectively) at the end of the evaluation period. The total average of injuries notes at the end of the bioassay did not differ between the genotypes. The number of mites/leaf was growing for the injury scale to the note 3.0, but when the injury scale approached the note 4.0, there was observed a decrease in the number of mites/leaf for all the genotypes.

A rapid survey technique for Tropilaelaps mite (Mesostigmata: Laclapidae) detection

USDA-ARS?s Scientific Manuscript database

Parasitic mites affect pollinator helath and the varroa mite (Varroa destructor Anderson and Trueman) is the most serious single threat to honey bees. Another group of mites with similar life histories to varroa mites, Tropilaelaps (Delfinado and Baker) species, have become a damaging pest of Europe...

Bee Mite ID: Bee-associated mite genera of the world

USDA-ARS?s Scientific Manuscript database

Bee Mite ID contains an interactive key, fact sheets, an image gallery, and abundant supporting information. The interactive key allows you to choose characters to obtain a list of mite genera possibly matching your specimen. Consult fact sheets to find images and information for a particular mite g...

Effect of a change to mite-free bedding on children with mite-sensitive asthma: a controlled trial.

PubMed Central

Burr, M L; Neale, E; Dean, B V; Verrier-Jones, E R

1980-01-01

Twenty-one children with mite-sensitive asthma took part in a crossover randomised controlled trial of mite-free bedding. Each child was issued with a new sleeping bag and pillow for a month, and twice-daily peak flow readings were compared with those obtained during a month in the child's ordinary bedding. Seventeen of the children had higher mean peak flow readings during the period in the mite-free bedding (p < 0.01). The overall improvement was only modest, however, and some mites had appeared in most of the bedding by the end of the trial. New bedding may be helpful to patients with mite-sensitive asthma, but methods are needed to prevent colonisation by mites. PMID:7001668

Prey preference of the predatory mite, Amblyseius swirskii between first instar western flower thrips Frankliniella occidentalis and nymphs of the twospotted spider mite Tetranychus urticae.

PubMed

Xu, Xuenong; Enkegaard, Annie

2010-01-01

The prey preference of polyphagous predators plays an important role in suppressing different species of pest insects. In this study the prey preference of the predatory mite, Amblyseius swirskii (Athias-Henriot) (Acari: Phytoseiidae) was examined between nymphs of the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) and first instar larvae of the western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), as well as between active and chrysalis spider mite protonymphs and active and chrysalis spider mite deutonymphs. The study was done in the laboratory on bean leaf discs at 25 ± 1° C and 70 ± 5% RH. Amblyseius swirskii had a clear preference for thrips compared to both spider mite protonymphs and deutonymphs. About twice as many thrips as spider mites were consumed. Amblyseius swirskii did not show a preference between active and chrysalis stages of spider mites.

Population-level effects of abamectin, azadirachtin and fenpyroximate on the predatory mite Neoseiulus baraki.

PubMed

Lima, Debora B; Melo, José W S; Gondim, Manoel G C; Guedes, Raul N C; Oliveira, José E M

2016-10-01

The coconut production system, in which the coconut mite Aceria guerreronis is considered a key pest, provides an interesting model for integration of biological and chemical control. In Brazil, the most promising biological control agent for the coconut mite is the phytoseiid predator Neoseiulus baraki. However, acaricides are widely used to control the coconut mite, although they frequently produce unsatisfactory results. In this study, we evaluated the simultaneous direct effect of dry residue contact and contaminated prey ingestion of the main acaricides used on coconut palms (i.e., abamectin, azadirachtin and fenpyroximate) on life-history traits of N. baraki and their offspring. These acaricides are registered, recommended and widely used against A. guerreronis in Brazil, and they were tested at their label rates. The offspring of the exposed predators was also evaluated by estimating the instantaneous rate of population increase (r i ). Abamectin compromised female performance, whereas fenpyroximate did not affect the exposed females (F0). Nonetheless, fenpyroximate strongly compromised the offspring (F1) net reproductive rate (R0), intrinsic rate of population growth (r i ), and doubling time (DT). In contrast, fenpyroximate did not have such effects on the 2nd generation (F2) of predators with acaricide-exposed grandparents. Azadirachtin did not affect the predators, suggesting that this acaricide can be used in association with biological control by this predatory species. In contrast, the use of abamectin and fenpyroximate is likely to lead to adverse consequences in the biological control of A. guerreronis using N. baraki.

Fluralaner as a single dose oral treatment for Caparinia tripilis in a pygmy African hedgehog.

PubMed

Romero, Camilo; Sheinberg Waisburd, Galia; Pineda, Jocelyn; Heredia, Rafael; Yarto, Enrique; Cordero, Alberto M

2017-12-01

African pygmy hedgehogs (Atelerix albiventris) are popular pets belonging to the Erinaceidae family of spined mammals. Amongst the most common skin diseases occurring in this species is infestation caused by the mite Caparinia spp. Due to their skin anatomy and spiny coat, detection of skin lesions in these hedgehogs can be difficult. This may result in delays in seeking medical care, which may lead to secondary bacterial infection and self-inflicted trauma. Multiple therapies have been used in the treatment of this skin condition including ivermectin, amitraz, fipronil and selamectin. A drug which could be administered as a single oral dose would be advantageous to these pets and their owners. To evaluate the effect of a single oral dose (15 mg/kg) of fluralaner on Caparinia tripilis infestation in the African pygmy hedgehog. A 10-month-old African pygmy hedgehog weighing 184 g. Response to treatment was monitored by dermatological examination and superficial skin scrapings repeated at 7, 14, 21, 30, 60, 90 and 120 days following fluralaner administration. On Day 7 after treatment, adult mites were observed exhibiting normal movement. On Day 14, only dead mites were observed. No life stages of the mites were found after Day 21. A single oral dose at 15 mg/kg of fluralaner was effective within 21 days after treatment for capariniasis in this case. Further studies are required to evaluate the drug's safety and toxicology in hedgehogs, and to confirm efficacy. © 2017 ESVD and ACVD.

Are humans the initial source of canine mange?

PubMed

Andriantsoanirina, Valérie; Fang, Fang; Ariey, Frédéric; Izri, Arezki; Foulet, Françoise; Botterel, Françoise; Bernigaud, Charlotte; Chosidow, Olivier; Huang, Weiyi; Guillot, Jacques; Durand, Rémy

2016-03-25

Scabies, or mange as it is called in animals, is an ectoparasitic contagious infestation caused by the mite Sarcoptes scabiei. Sarcoptic mange is an important veterinary disease leading to significant morbidity and mortality in wild and domestic animals. A widely accepted hypothesis, though never substantiated by factual data, suggests that humans were the initial source of the animal contamination. In this study we performed phylogenetic analyses of populations of S. scabiei from humans and from canids to validate or not the hypothesis of a human origin of the mites infecting domestic dogs. Mites from dogs and foxes were obtained from three French sites and from other countries. A part of cytochrome c oxidase subunit 1 (cox1) gene was amplified and directly sequenced. Other sequences corresponding to mites from humans, raccoon dogs, foxes, jackal and dogs from various geographical areas were retrieved from GenBank. Phylogenetic analyses were performed using the Otodectes cynotis cox1 sequence as outgroup. Maximum Likelihood and Bayesian Inference analysis approaches were used. To visualize the relationship between the haplotypes, a median joining haplotype network was constructed using Network v4.6 according to host. Twenty-one haplotypes were observed among mites collected from five different host species, including humans and canids from nine geographical areas. The phylogenetic trees based on Maximum Likelihood and Bayesian Inference analyses showed similar topologies with few differences in node support values. The results were not consistent with a human origin of S. scabiei mites in dogs and, on the contrary, did not exclude the opposite hypothesis of a host switch from dogs to humans. Phylogenetic relatedness may have an impact in terms of epidemiological control strategy. Our results and other recent studies suggest to re-evaluate the level of transmission between domestic dogs and humans.

A Three-Year Course of House Dust Mite Sublingual Immunotherapy Appears Effective in Controlling the Symptoms of Allergic Rhinitis.

PubMed

Novakova, Silviya M; Novakova, Plamena I; Yakovliev, Plamen H; Staevska, Maria T; Mateva, Nonka G; Dimcheva, Teodora D; Peichev, Jivko L

2018-05-01

Background Allergic rhinitis is the most common allergic disorder. Although the management of the disease is successful in many patients, based on guidelines, some of them remain with symptoms uncontrolled with pharmacotherapy. Presently, there is no substantiated information on the control of allergic rhinitis in patients who underwent sublingual immunotherapy. Objective The purpose of this prospective follow-up study was to assess the control of allergic rhinitis in adults after a three-year course of house dust mite sublingual immunotherapy. Methods This prospective real-life study was designed to include adults with moderate to severe allergic rhinitis sensitized to house dust mite who underwent a three-year course of sublingual immunotherapy. Control of symptoms was assessed by Rhinitis Control Assessment Test (RCAT) after three years of house dust mite sublingual immunotherapy. Additionally, patients assessed their symptoms by utilizing a visual analog scale. Results A total number of 86 consecutively enrolled patients (46 (53.49%) men; mean age 26.10 years (SD = 5.85)) with moderate to severe allergic rhinitis and clinically relevant sensitization to house dust mite were evaluated. When assessed by RCAT on the third year, 74 (86.05%) had well-controlled symptoms and 20 (27.03%) of them were completely controlled. A significant reduction in visual analog scale scores-from 7.52 cm at baseline to 2.31 cm-was established ( P < 0.0001). There was a strong negative correlation between RCAT scores and visual analog scale (r = -0.65; P < 0.01). Conclusion This study provided evidence that a three-year course of house dust mite sublingual immunotherapy appears effective in controlling the symptoms of allergic rhinitis.

Laboratory evaluation of a native strain of Beauveria bassiana for controlling Dermanyssus gallinae (De Geer, 1778) (Acari: Dermanyssidae).

PubMed

Immediato, Davide; Camarda, Antonio; Iatta, Roberta; Puttilli, Maria Rita; Ramos, Rafael Antonio Nascimento; Di Paola, Giancarlo; Giangaspero, Annunziata; Otranto, Domenico; Cafarchia, Claudia

2015-09-15

The poultry red mite, Dermanyssus gallinae (De Geer, 1778) (Acari: Dermanyssidae) is one of the most economically important ectoparasites of laying hens worldwide. Chemical control of this mite may result in environmental and food contamination, as well as the development of drug resistance. High virulence of Beauveria bassiana sensu lato strains isolated from naturally infected hosts or from their environment has been demonstrated toward many arthropod species, including ticks. However, a limited number of studies have assessed the use of B. bassiana for the control of D. gallinae s.l. and none of them have employed native strains. This study reports the pathogenicity of a native strain of B. bassiana (CD1123) against nymphs and adults of D. gallinae. Batches of nymph and adult mites (i.e., n=720 for each stage) for treated groups (TGs) were placed on paper soaked with a 0.1% tween 80 suspension of B. bassiana (CIS, 10(5), 10(7) and 10(9) conidia/ml), whilst 240 untreated control mites for each stage (CG) were exposed only to 0.1% tween 80. The mites in TG showed a higher mortality at all stages (p<0.01) when compared to CG, depending on the time of exposure and the conidial concentration. A 100% mortality rate was recorded using a CIS of 10(9) conidia/ml 12 days post infection (DPI) in adults and 14 DPI in nymphs. B. bassiana suspension containing 10(9) conidia/ml was highly virulent towards nymph and adult stages of D. gallinae, therefore representing a possible promising natural product to be used in alternative or in combination to other acaricidal compounds currently used for controlling the red mite. Copyright © 2015 Elsevier B.V. All rights reserved.

Efficacy of an imidacloprid/flumethrin collar against fleas, ticks, mites and lice on dogs

PubMed Central

2012-01-01

Background The studies reported here were conducted to ascertain the efficacy of imidacloprid/flumethrin incorporated in a slow-release matrix collar, against infestations of dogs by fleas, ticks, mites and lice. Efficacy was evaluated against the flea Ctenocephalides felis felis, the ticks Rhipicephalus sanguineus, Ixodes ricinus, Ixodes scapularis, Dermacentor reticulatus and Dermacentor variabilis, the mite Sarcoptes scabiei and the biting louse Trichodectes canis. Methods Groups of collar-treated dogs (n = 7–10) were infested with fleas and/or ticks at monthly intervals at least, over a period of up to 8 months. Efficacy against fleas was evaluated 24 to 48 h after treatment and 24 h after each re-infestation. Efficacy against ticks was evaluated at 48 h (acaricidal), 6 h (repellent) and 48 h (sustained) after infestation. The effect of regular shampooing or immersion in water on the efficacy of the collars was also tested. Efficacy against flea larvae was assessed by incubating blanket samples after dog contact with viable flea eggs. Effectiveness against lice and mites was evaluated after treatment of naturally infested animals. With the exception of the mites, efficacy was calculated by comparison with untreated negative control groups. Results Efficacy against fleas (24 h) generally exceeded 95%, and against flea larvae it exceeded 99% for 8 months. Sustained acaricidal (48 h) efficacy, covering a period of 8 months was 100% against I. ricinus, starting 2 days after treatment (in vivo), and 100% against I. scapularis (in vitro), above 97% against R. sanguineus, generally above 97% against D. reticulatus and above 90% for D. variabilis. Repellent (6 h) efficacy 2 days after treatment and continuing for 8 months was consistently 100% against I. ricinus, and above 90% against R. sanguineus. Regular shampooing affected efficacy against fleas and ticks to a lesser extent than regular immersion in water. The collars eliminated Trichodectes canis within 2 days and Sarcoptes scabiei within 3 months. Conclusion The rapid insecticidal and acaricidal properties of the medicated collars against newly-acquired infestations of fleas and ticks and their sustained high levels of preventive efficacy have been clearly shown. Consequently they have the potential to prevent the transmission of vector-borne diseases and other conditions directly associated with infestation throughout an entire season of parasite abundance. PMID:22647530

Evolutionary genomics of miniature inverted-repeat transposable elements (MITEs) in Brassica.

PubMed

Nouroz, Faisal; Noreen, Shumaila; Heslop-Harrison, J S

2015-12-01

Miniature inverted-repeat transposable elements (MITEs) are truncated derivatives of autonomous DNA transposons, and are dispersed abundantly in most eukaryotic genomes. We aimed to characterize various MITEs families in Brassica in terms of their presence, sequence characteristics and evolutionary activity. Dot plot analyses involving comparison of homoeologous bacterial artificial chromosome (BAC) sequences allowed identification of 15 novel families of mobile MITEs. Of which, 5 were Stowaway-like with TA Target Site Duplications (TSDs), 4 Tourist-like with TAA/TTA TSDs, 5 Mutator-like with 9-10 bp TSDs and 1 novel MITE (BoXMITE1) flanked by 3 bp TSDs. Our data suggested that there are about 30,000 MITE-related sequences in Brassica rapa and B. oleracea genomes. In situ hybridization showed one abundant family was dispersed in the A-genome, while another was located near 45S rDNA sites. PCR analysis using primers flanking sequences of MITE elements detected MITE insertion polymorphisms between and within the three Brassica (AA, BB, CC) genomes, with many insertions being specific to single genomes and others showing evidence of more recent evolutionary insertions. Our BAC sequence comparison strategy enables identification of evolutionarily active MITEs with no prior knowledge of MITE sequences. The details of MITE families reported in Brassica enable their identification, characterization and annotation. Insertion polymorphisms of MITEs and their transposition activity indicated important mechanism of genome evolution and diversification. MITE families derived from known Mariner, Harbinger and Mutator DNA transposons were discovered, as well as some novel structures. The identification of Brassica MITEs will have broad applications in Brassica genomics, breeding, hybridization and phylogeny through their use as DNA markers.

Mould-devouring mites differ in guanine excretion from dust-eating Acari, a possible error source in mite allergen exposure studies.

PubMed

Kort, H S; Schober, G; Koren, L G; Scharringa, J

1997-08-01

Measurement of guanine in dust proved a good assessment of mite allergen exposure. Exposure to mite allergens may lead to atopic inflictions. In a semi-natural test system the development of Dermatophagoides pteronyssinus (Trouessart) and Glycyphagus domesticus (De Geer), and the presence of their guanine excretion, was examined in a dust-soiled and mouldy environment. Mites were counted after heat-escape, and guanine was detected by means of capillary zone electrophoresis. For each species, 50 mites randomly taken, were inoculated on soiled test-surfaces of 10 x 10 cm. Rough wooden board, gypsum board, tufted carpet, and a self-made mattress representing wall surfaces and home-textiles, respectively, were used. Eight weeks after inoculation with mites only, the surfaces were all mould ridden, and mite and guanine measurements were taken. The Spearman rank correlation test and the Mann-Whitney U-test were used in statistical analysis. The confidence limit was set at 1%. Among the various test-surfaces, no differences were found regarding total mite numbers and amount of guanine present (P > 0.01). For the dust-eating mite D. pteronyssinus, total mite numbers correlated with the amount of guanine present (P = 0.002) on all inoculated surfaces, indicating feeding on the protein-rich dust. For the mould devouring mite G. domesticus, however, no such correlation was found (P = 0.72). Apparently, they mainly consumed fungal carbohydrates during this experiment. The allergological relevance of storage mites has been under discussion for the last 25 years. In humid homes, these mites will feed almost exclusively on fungi and may produce allergenic or irritating substances different from those arising on protein-rich laboratory media used in allergen extract production or present in carpets, bedding and furniture.

Do Phoretic Mites Influence the Reproductive Success of Ips grandicollis (Coleoptera: Curculionidae)?

PubMed

Pfammatter, Jesse A; Raffa, Kenneth F

2015-12-01

Ips grandicollis (Eichhoff) can be an important pest of plantation trees in the Great Lakes region. Mites commonly occur in phoretic association with this beetle, but little is known about their effects on beetle population dynamics. We assessed the effects of phoretic mites on the reproductive success of I. grandicollis using complementary correlative and manipulative approaches. First, we allowed beetles to colonize Pinus resinosa (Ait) logs from sites across Wisconsin, reared them in a common environment, and related the species identities and abundances of mites with beetle production from each log. We found a positive relationship between I. grandicollis abundance and the presence of five mite species, Histiostoma spp., Dendrolaelaps quadrisetus (Berlese), Iponemus confusus (Lindquist), Trichouropoda australis Hirschmann, and Tarsonemus spp. While the abundance of individual mite species was positively correlated with beetle abundance, assessments of mite community structure did not explain beetle reproduction. Next, we introduced beetles that either had a natural complement of mites or whose mites were mechanically reduced into logs, and compared reproductive success between these beetles. We found no difference in colonization rates or beetle emergence between mite-present and mite-reduced treatments. Collectively, these results suggest a correlative, rather than causal, link between beetle reproductive success and mite incidence and abundances. These mites and beetles likely benefit from mutually suitable environments rather than exerting strong reciprocal impacts. Although mites may have some effects on I. grandicollis reproductive success, they likely play a minimal role compared to factors such as tree quality, beetle predation, and weather. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Oral Mite Anaphylaxis Caused by Mite-Contaminated Okonomiyaki/Pancake-Mix in Japan: 8 Case Reports and a Review of 28 Reported Cases.

PubMed

Takahashi, Kentaro; Taniguchi, Masami; Fukutomi, Yuma; Sekiya, Kiyoshi; Watai, Kentaro; Mitsui, Chihiro; Tanimoto, Hidenori; Oshikata, Chiyako; Tsuburai, Takahiro; Tsurikisawa, Naomi; Minoguchi, Kenji; Nakajima, Hiroshi; Akiyama, Kazuo

2014-01-01

Anaphylaxis after the ingestion of foods contaminated with mites has recently been recognized. Case series and case reports thus far have shown that mite-contaminated wheat flour is the major cause of oral mite anaphylaxis. However, we have found 8 cases of oral mite anaphylaxis which were caused by mitecontaminated okonomiyaki-mix, a savory Japanese style pancake mix, in our hospital. In addition to our 8 cases, the databases of MEDLINE and ICHUSHI were systematically searched for patients with oral mite anaphylaxis in Japan. Thirty-six patients including our 8 cases with oral mite anaphylaxis were identified. Thirty-four out of 36 cases (94%) ingested okonomiyaki or takoyaki, prepared at home using okonomiyaki-mix or takoyaki-mix which was previously opened and stored for months at ambient temperature. Microscopic examination of culprit mixes of 16 cases including our 1 case revealed contamination of mites such as Dermatophagoides farina (Der f) (5 cases), Tyrophagus putrescentiae (Tyr p) (4 cases), and Dermatophagoides pteronyssinus (Der p) (3 cases). The specific IgE to each mite is generally upregulated in these patients. Especially, the titers of specific IgE to Der p and Der f were more than class 2 in all cases. Mite-contaminated flavored flour is the major cause of oral mite anaphylaxis in Japan. © 2014 Japanese Society of Allergology.

Predatory potential of Euseius alatus (Phytoseiidae) on different life stages of Oligonychus ilicis (Tetranychidae) on coffee leaves under laboratory conditions.

PubMed

de Toledo, M A; Reis, P R; da Silveira, E C; de P Marafeli, P; de Souza-Pimentel, G C

2013-04-01

This study evaluated the predatory capacity of Euseius alatus (DeLeon) as a biological control agent of the pest mite Oligonychus ilicis (McGregor) on coffee leaves under laboratory conditions, using arenas containing 25 O. ilicis per coffee (Coffea arabica) leaf to one specimen of each stage of the predator mite. The functional response and oviposition rate of adult females of E. alatus were evaluated on coffee leaf arenas and offered from 1 to 125 immature stages of O. ilicis per arena. The number of preys killed and the number of eggs laid by the predator were evaluated every 24 h during 8 days. The preys consumed were daily replaced. Male and female adults of E. alatus were the most efficient in killing all developmental stages of O. ilicis. Larvae and nymphs of O. ilicis were the most consumed by all stages of the predatory mite. The functional response and oviposition rates of E. alatus increased as the prey density increased, with a positive and highly significant correlation. Regression analysis suggested a type II functional response, with a maximum predation of 22 O. ilicis/arena and a maximum oviposition rate of 1.7 eggs/day at a density of 70 O. ilicis/arena.

The role of mites in insect-fungus associations

Treesearch

R. W. Hofstetter; J. C. Moser

2014-01-01

The interactions among insects, mites, and fungi are diverse and complex but poorly understood in most cases. Associations among insects, mites, and fungi span an almost incomprehensible array of ecological interactions and evolutionary histories. Insects and mites often share habitats and resources and thus interact within communities. Many mites and insects rely on...

Strong indirect interactions of Tarsonemus mites (Acarina: Tarsonemidae) and Dendroctonus frontalis (Coleoptera: Scolytidae)

Treesearch

Maria J. Lombardero; Matthew P. Ayres; Richard W. Hofstetter; John C. Moser; Kier D. Lepzig

2003-01-01

Phoretic mites of bark beetles are classic examples of commensal ectosymbionts. However, many such mites appear to have mutualisms with fungi that could themselves interact with beetles. We tested for indirect effects of phoretic mites on Dendroctonus frontalis, which auacks and kills pine trees in North America. Tarsonemus mites...

Abundances and host relationships of chigger mites in Yunnan Province, China.

PubMed

Zhan, Y-Z; Guo, X-G; Speakman, J R; Zuo, X-H; Wu, D; Wang, Q-H; Yang, Z-H

2013-06-01

This paper reports on ectoparasitic chigger mites found on small mammals in Yunnan Province, southwest China. Data were accumulated from 19 investigation sites (counties) between 2001 and 2009. A total of 10 222 small mammal hosts were captured and identified; these represented 62 species, 34 genera and 11 families in five orders. From the body surfaces of these 10 222 hosts, a total of 92 990 chigger mites were collected and identified microscopically. These represented 224 species, 22 genera and three subfamilies in the family Trombiculidae (Trombidiformes). Small mammals were commonly found to be infested by chigger mites and most host species harboured several species of mite. The species diversity of chigger mites in Yunnan was much higher than diversities reported previously in other provinces of China and in other countries. A single species of rodent, Eothenomys miletus (Rodentia: Cricetidae), carried 111 species of chigger mite, thus demonstrating the highest species diversity and heaviest mite infestation of all recorded hosts. This diversity is exceptional compared with that of other ectoparasites. Of the total 224 mite species, 21 species accounted for 82.2% of all mites counted. Two species acting as major vectors for scrub typhus (tsutsugamushi disease), Leptotrombidium scutellare and Leptotrombidium deliense, were identified as the dominant mite species in this sample. In addition to these two major vectors, 12 potential or suspected vector species were found. Most species of chigger mite had a wide range of hosts and low host specificity. For example, L. scutellare parasitized 30 species of host. The low host specificity of chigger mites may increase their probability of encountering humans, as well as their transmission of scrub typhus among different hosts. Hierarchical clustering analysis showed that similarities between different chigger mite communities on the 18 main species of small mammal host did not accord with the taxonomic affinity of the hosts. This suggests that the distribution of chigger mites may be strongly influenced by the environment in which hosts live. © 2012 The Royal Entomological Society.

The Role of Dust Mites in Allergy.

PubMed

Miller, Jeffrey D

2018-06-23

House dust mites are an unsurpassed cause of atopic sensitization and allergic illness throughout the world. The major allergenic dust mites Dermatophagoides pteronyssinus, Dermatophagoides farinae, Euroglyphus maynei, and Blomia tropicalis are eight-legged members of the Arachnid class. Their approximately 3-month lifespan comprises egg, larval, protonymph, tritonymph, and adult stages, with adults, about one fourth to one third of a millimeter in size, being at the threshold of visibility. The geographic and seasonal distributions of dust mites are determined by their need for adequate humidity, while their distribution within substrates is further determined by their avoidance of light. By contacting the epithelium of the eyes, nose, lower airways, skin, and gut, the allergen-containing particles of dust mites can induce sensitization and atopic symptoms in those organs. Various mite allergens, contained primarily in mite fecal particles but also in shed mite exoskeletons and decaying mite body fragments, have properties that include proteolytic activity, homology with the lipopolysaccharide-binding component of Toll-like receptor 4, homology with other invertebrate tropomyosins, and chitin-cleaving and chitin-binding activity. Mite proteases have direct epithelial effects including the breaching of tight junctions and the stimulation of protease-activated receptors, the latter inducing pruritus, epithelial dysfunction, and cytokine release. Other components, including chitin, unmethylated mite and bacterial DNA, and endotoxin, activate pattern recognition receptors of the innate immune system and act as adjuvants promoting sensitization to mite and other allergens. Clinical conditions resulting from mite sensitization and exposure include rhinitis, sinusitis, conjunctivitis, asthma, and atopic dermatitis. Systemic allergy symptoms can also occur from the ingestion of cross-reacting invertebrates, such as shrimp or snail, or from the accidental ingestion of mite-contaminated foods. Beyond their direct importance as a major allergen source, an understanding of dust mites leads to insights into the nature of atopy and of allergic sensitization in general.

Antigenic relationship between the house dust mite Dermatophagoides farinae and the predacious mite Phytoseiulus persimilis.

PubMed

Homma, R; Ando, T; Miyahara, A; Kimura, H; Ito, G; Uesato, N; Ino, Y; Iwaki, M

1994-12-01

We have examined the antigenic relationship between the house dust mite Dermatophagoides farinae and the predacious mite Phytoseiulus persimilis. Immunoblotting analysis demonstrated that there was a very weak antigenic cross-reactivity between these different suborder of mites but that this cross-reactivity was not attributed to D. farinaes major allergen's, Der fI and Der fII. These results suggest that P. persimilis might scarcely provoke allergic symptoms in patients sensitized to house dust mites.

Baseline susceptibility of persea mite (Acari: Tetranychidae) to abamectin and milbemectin in avocado groves in Southern California.

PubMed

Humeres, Eduardo C; Morse, Joseph G

2005-01-01

Persea mite, Oligonychus perseae Tuttle, Baker, and Abatiello, susceptibility to abamectin and milbemectin was evaluated in 2003 to determine baseline susceptibility levels in avocado groves in San Diego and Ventura Counties (California, USA) where more than 70% of the state's avocado production is concentrated. Milbemectin has yet to be used in avocado production in California and abamectin has been available for use since 1999. Baseline susceptibility ratios (in relation to the most susceptible population) of five persea mite field strains to milbemectin varied 2.1- to 2.8-fold at the LC50 and LC90, respectively. The susceptibility of seven field strains to abamectin varied slightly more (2.1- to 3.5-fold) with one strain subjected to seven sprays over the past 4 years showing slight but significant separation of LC50 and LC90's from the most susceptible strain, which is suggestive of the early stages of resistance to this product. Based on these data, baseline susceptibility levels are proposed that might be used to monitor for future persea mite resistance to these chemicals as their use in California avocado production continues.

Impact of two treatments of a formulation of Beauveria bassiana (Deuteromycota: Hyphomycetes) conidia on Varroa mites (Acari: Varroidae) and on honeybee (Hymenoptera: Apidae) colony health.

PubMed

Meikle, William G; Mercadier, Guy; Holst, Niels; Girod, Vincent

2008-12-01

Bee colonies in southern France were treated with conidia (asexual spores) from two strains of Beauveria bassiana, an entomopathogenic fungus. One strain was commercial (GHA) and the other had been isolated from Varroa mites in the region (Bb05002). Objectives were to evaluate treatment effect on colony weight, adult bee mass, capped brood, and on Varroa fall onto sticky boards. Treatments included conidia formulated with either carnauba or candelilla wax powder, candelilla wax powder alone, or control; in two treatment groups formulation was applied a second time after one week. Treatment did not affect colony health. Colonies treated twice with Bb05002 conidia and carnauba wax powder had significantly higher mite fall compared to colonies treated with blank candelilla wax powder. The proportion of fallen mites that were infected in both conidia treatments was higher than controls for 18 days after the second treatment. The number of fungal propagules on the bees themselves remained elevated for about 14 days after the second treatment. These results were compared to published results from previous experiments with regard to infection duration.

Evaluation of home allergen sampling devices.

PubMed

Sercombe, J K; Liu-Brennan, D; Garcia, M L; Tovey, E R

2005-04-01

Simple, inexpensive methods of sampling from allergen reservoirs are necessary for large-scale studies or low-cost householder-operated allergen measurement. We tested two commercial devices: the Indoor Biotechnologies Mitest Dust Collector and the Drager Bio-Check Allergen Control; two devices of our own design: the Electrostatic Cloth Sampler (ECS) and the Press Tape Sampler (PTS); and a Vacuum Sampler as used in many allergen studies (our Reference Method). Devices were used to collect dust mite allergen samples from 16 domestic carpets. Results were examined for correlations between the sampling methods. With mite allergen concentration expressed as microg/g, the Mitest, the ECS and the PTS correlated with the Reference Method but not with each other. When mite allergen concentration was expressed as microg/m2 the Mitest and the ECS correlated with the Reference Method but the PTS did not. In the high allergen conditions of this study, the Drager Bio-Check did not relate to any methods. The Mitest Dust Collector, the ECS and the PTS show performance consistent with the Reference Method. Many techniques can be used to collect dust mite allergen samples. More investigation is needed to prove any method as superior for estimating allergen exposure.

Vulnerability and behavioral response to ultraviolet radiation in the components of a foliar mite prey-predator system.

PubMed

Tachi, Fuyuki; Osakabe, Masahiro

2012-12-01

Ambient ultraviolet-B (UVB) radiation impacts plant-dwelling arthropods including herbivorous and predatory mites. However, the effects of UVB on prey-predator systems, such as that between the herbivorous spider mite and predatory phytoseiid mite, are poorly understood. A comparative study was conducted to determine the vulnerability and behavioral responses of these mites to ultraviolet (UV) radiation. First, we analyzed dose-response (cumulative irradiance-mortality) curves for the eggs of phytoseiid mites (Neoseiulus californicus, Neoseiulus womersleyi, and Phytoseiulus persimilis) and the spider mite (Tetranychus urticae) to UVB radiation from a UV lamp. This indicated that the phytoseiid mites were more vulnerable than the spider mite, although P. persimilis was slightly more tolerant than the other two phytoseiid mites. Second, we compared the avoidance behavior of adult female N. californicus and two spider mite species (T. urticae, a lower leaf surface user; Panonychus citri, an upper leaf surface user) in response to solar UV and visible light. N. californicus actively avoided both types of radiation, whereas P. citri showed only minimal avoidance behavior. T. urticae actively avoided UV as well as N. californicus but exhibited a slow response to visible light as well as P. citri. Such variation in vulnerability and avoidance behavior accounts for differences in the species adaptations to solar UVB radiation. This may be the primary factor determining habitat use among these mites on host plant leaves, subsequently affecting accessibility by predators and also intraguild competition.

Number of hummingbird visits determines flower mite abundance on hummingbird feeders.

PubMed

Márquez-Luna, Ubaldo; Vázquez González, María Magdalena; Castellanos, Ignacio; Ortiz-Pulido, Raúl

2016-08-01

Members of several genera of mites from the family Melicharidae (Mesostigmata) use hummingbirds as transport host to move from flower to flower, where they feed on pollen and nectar. The factors that influence hummingbird flower mite abundance on host plant flowers are not currently known. Here we tested whether hummingbird flower mite abundance on an artificial nectar source is determined by number of hummingbird visits, nectar energy content or species richness of visiting hummingbirds. We conducted experiments employing hummingbird feeders with sucrose solutions of low, medium, and high energy concentrations, placed in a xeric shrubland. In the first experiment, we recorded the number of visiting hummingbirds and the number of visiting hummingbird species, as well as the abundance of hummingbird flower mites on each feeder. Feeders with the highest sucrose concentration had the most hummingbird visits and the highest flower mite abundances; however, there was no significant effect of hummingbird species richness on mite abundance. In the second experiment, we recorded flower mite abundance on feeders after we standardized the number of hummingbird visits to them. Abundance of flower mites did not differ significantly between feeders when we controlled for hummingbird visits. Our results suggest that nectar energy concentration determines hummingbird visits, which in turn determines flower mite abundance in our feeders. Our results do not support the hypothesis that mites descend from hummingbird nostrils more on richer nectar sources; however, it does not preclude the possibility that flower mites select for nectar concentration at other spatial and temporal scales.

Spatial distributions of the red palm mite, Raoiella indica (Acari: Tenuipalpidae) on coconut and their implications for development of efficient sampling plans.

PubMed

Roda, A; Nachman, G; Hosein, F; Rodrigues, J C V; Peña, J E

2012-08-01

The red palm mite (Raoiella indica), an invasive pest of coconut, entered the Western hemisphere in 2004, then rapidly spread through the Caribbean and into Florida, USA. Developing effective sampling methods may aid in the timely detection of the pest in a new area. Studies were conducted to provide and compare intra tree spatial distribution of red palm mite populations on coconut in two different geographical areas, Trinidad and Puerto Rico, recently invaded by the mite. The middle stratum of a palm hosted significantly more mites than fronds from the upper or lower canopy and fronds from the lower stratum, on average, had significantly fewer mites than the two other strata. The mite populations did not vary within a frond. Mite densities on the top section of the pinna had significantly lower mite densities than the two other sections, which were not significantly different from each other. In order to improve future sampling plans for the red palm mite, the data was used to estimate the variance components associated with the various levels of the hierarchical sampling design. Additionally, presence-absence data were used to investigate the probability of no mites being present in a pinna section randomly chosen from a frond inhabited by mites at a certain density. Our results show that the most precise density estimate at the plantation level is to sample one pinna section per tree from as many trees as possible.

Vulnerability and behavioral response to ultraviolet radiation in the components of a foliar mite prey-predator system

NASA Astrophysics Data System (ADS)

Tachi, Fuyuki; Osakabe, Masahiro

2012-12-01

Ambient ultraviolet-B (UVB) radiation impacts plant-dwelling arthropods including herbivorous and predatory mites. However, the effects of UVB on prey-predator systems, such as that between the herbivorous spider mite and predatory phytoseiid mite, are poorly understood. A comparative study was conducted to determine the vulnerability and behavioral responses of these mites to ultraviolet (UV) radiation. First, we analyzed dose-response (cumulative irradiance-mortality) curves for the eggs of phytoseiid mites ( Neoseiulus californicus, Neoseiulus womersleyi, and Phytoseiulus persimilis) and the spider mite ( Tetranychus urticae) to UVB radiation from a UV lamp. This indicated that the phytoseiid mites were more vulnerable than the spider mite, although P. persimilis was slightly more tolerant than the other two phytoseiid mites. Second, we compared the avoidance behavior of adult female N. californicus and two spider mite species ( T. urticae, a lower leaf surface user; Panonychus citri, an upper leaf surface user) in response to solar UV and visible light. N. californicus actively avoided both types of radiation, whereas P. citri showed only minimal avoidance behavior. T. urticae actively avoided UV as well as N. californicus but exhibited a slow response to visible light as well as P. citri. Such variation in vulnerability and avoidance behavior accounts for differences in the species adaptations to solar UVB radiation. This may be the primary factor determining habitat use among these mites on host plant leaves, subsequently affecting accessibility by predators and also intraguild competition.

Establishment of Demodex canis on canine skin engrafted onto scid-beige mice.

PubMed

Caswell, J L; Yager, J A; Barta, J R; Parker, W

1996-12-01

A small animal model of canine demodicosis is described. Normal canine skin was engrafted onto scid (severe combined immunodeficient)-beige mice, which lack functional B and T lymphocytes and have reduced natural killer cell activity. The xenografts were later infected with Demodex canis collected from a dog with demodicosis. At 30-112 days following infection, mites were seen histologically in the canine hair follicles of the engrafted skin. Demodex canis adults, nymphs, larvae, and eggs were present in samples macerated in sodium hydroxide. Mite infestations could not be demonstrated in the mouse skin, nor were mites passed from the infected graft to uninfected skin grafts on in-contact mice. This model may be utilized to assess the efficacy of miticidal treatments, to evaluate the importance of specific components of the immune response, and to study the biology of D. canis.

Impact of vineyard pesticides on a beneficial arthropod, Typhlodromus pyri (Acari: Phytoseiidae), in laboratory bioassays.

PubMed

Gadino, Angela N; Walton, Vaughn M; Dreves, Amy J

2011-06-01

Laboratory bioassays were conducted to evaluate the effects of six vineyard pesticides on Typhlodromus pyri Scheuten (Acari: Phytoseiidae), a key predator of the mite Calepitrimerus vitis Nalepa (Acari: Eriophyoidae), in Pacific coastal vineyards. Materials tested were whey powder, 25% boscalid + 13% pyraclostrobin (Pristine), 40% myclobutanil (Rally), micronized sulfur (92% WP), 75% ethylene bisdithiocarbamate (mancozeb; Manzate), and 91.2% paraffinic oil (JMS Stylet), all applied at three concentrations. Pesticide dilutions were directly sprayed onto T. pyri adult females and juveniles, and each treatment was assessed to determine effects on direct mortality and fecundity. Five of the six pesticides tested resulted in < 50% mortality to adult and juvenile T. pyri for all concentrations 7 d after treatment. Paraffinic oil treatments displayed direct mortality > 50% for adult and juvenile assays and resulted in significantly higher mortality. Sublethal effects were more pronounced than acute pesticide toxicity, particularly in juvenile mite bioassays. Significant decreases in fecundity were detected in the sulfur and mancozeb treatments compared with the control in juvenile tests. The relative percentage of fecundity reduction for juvenile mites was highest when applying mancozeb (> 70%), sulfur (> 25%), or myclobutanil (> 20%). Adult mites displayed the greatest reductions in fecundity from applications of paraffinic oil (> 20%) or mancozeb (> 15%) treatments. Boscalid (+ pyraclostrobin) and whey displayed the least effect on fecundity across all bioassays. These results can be used to develop management guidelines in vineyard pest management practices to help conserve and enhance predatory mite populations.

Fluorescein dye improves microscopic evaluation and counting of demodex in blepharitis with cylindrical dandruff.

PubMed

Kheirkhah, Ahmad; Blanco, Gabriela; Casas, Victoria; Tseng, Scheffer C G

2007-07-01

To show whether fluorescein dye helps detect and count Demodex embedded in cylindrical dandruff (CD) of epilated eyelashes from patients with blepharitis. Two eyelashes with CD were removed from each lid of 10 consecutive patients with blepharitis and subjected to microscopic examination with and without fluorescein solution to detect and count Demodex mites. Of 80 eyelashes examined, 36 (45%) lashes retained their CD after removal. Before addition of the fluorescein solution, the mean total Demodex count per patient was 14.9 +/- 10 and the mean Demodex count per lash was 3.1 +/- 2.5 and 0.8 +/- 0.7 in epilated eyelashes with and without retained CD, respectively (P < 0.0001). After addition of the fluorescein solution, opaque and compact CD instantly expanded to reveal embedded mites in a yellowish and semitransparent background. As a result, the mean total Demodex count per patient was significantly increased to 20.2 +/- 13.8 (P = 0.003), and the mean count per lash was significantly increased to 4.4 +/- 2.8 and 1 +/- 0.8 in eyelashes with and without retained CD (P < 0.0001 and P = 0.007), respectively. This new method yielded more mites in 8 of 10 patients and allowed mites to be detected in 3 lashes with retained CD and 1 lash without retained CD that had an initial count of zero. Addition of fluorescein solution after mounting further increases the proficiency of detecting and counting mites embedded in CD of epilated eyelashes.

Surveying mites (Acarina) Phoretic on the southern pine beetle (Coleoptera: Scolytidae) with sticky traps

Treesearch

John C. Moser

1976-01-01

Sticky traps caught large numbers of mites that adhere tightly or ride in protected places on attacking southern pine beetles and tetreived seom of the mites that are loosely attached. Of the 2539 beetles surveyed, only 39.6% carried mites. Seven species of phoretic mites were found; thw two most common, Tarsonemus krantzi and Trichouropoda...

Ectoparasitic mites and their Drosophila hosts.

PubMed

Perez-Leanos, Alejandra; Loustalot-Laclette, Mariana Ramirez; Nazario-Yepiz, Nestor; Markow, Therese Ann

2017-01-02

Only two parasite interactions are known for Drosophila to date: Allantonematid nematodes associated with mycophagous Drosophilids and the ectoparasitic mite Macrocheles subbadius with the Sonoran Desert endemic Drosophila nigrospiracula. Unlike the nematode-Drosophila association, breadth of mite parasitism on Drosophila species is unknown. As M. subbadius is a generalist, parasitism of additional Drosophilids is expected. We determined the extent and distribution of mite parasitism in nature Drosophilids collected in Mexico and southern California. Thirteen additional species of Drosophilids were infested. Interestingly, 10 belong to the repleta species group of the subgenus Drosophila, despite the fact that the majority of flies collected were of the subgenus Sophophora. In all cases but 2, the associated mites were M. subbadius. Drosophila hexastigma was found to have not only M. subbadius, but another Mesostigmatid mite, Paragarmania bakeri, as well. One D. hydei was also found to have a mite from genus Lasioseius attached. In both choice and no-choice experiments, mites were more attracted to repleta group species than to Sophophoran. The extent of mite parasitism clearly is much broader than previously reported and suggests a host bias mediated either by mite preference and/or some mechanism of resistance in particular Drosophilid lineages.

Ectoparasitic mites and their Drosophila hosts

PubMed Central

Perez-Leanos, Alejandra; Loustalot-Laclette, Mariana Ramirez; Nazario-Yepiz, Nestor; Markow, Therese Ann

2017-01-01

ABSTRACT Only two parasite interactions are known for Drosophila to date: Allantonematid nematodes associated with mycophagous Drosophilids and the ectoparasitic mite Macrocheles subbadius with the Sonoran Desert endemic Drosophila nigrospiracula. Unlike the nematode-Drosophila association, breadth of mite parasitism on Drosophila species is unknown. As M. subbadius is a generalist, parasitism of additional Drosophilids is expected. We determined the extent and distribution of mite parasitism in nature Drosophilids collected in Mexico and southern California. Thirteen additional species of Drosophilids were infested. Interestingly, 10 belong to the repleta species group of the subgenus Drosophila, despite the fact that the majority of flies collected were of the subgenus Sophophora. In all cases but 2, the associated mites were M. subbadius. Drosophila hexastigma was found to have not only M. subbadius, but another Mesostigmatid mite, Paragarmania bakeri, as well. One D. hydei was also found to have a mite from genus Lasioseius attached. In both choice and no-choice experiments, mites were more attracted to repleta group species than to Sophophoran. The extent of mite parasitism clearly is much broader than previously reported and suggests a host bias mediated either by mite preference and/or some mechanism of resistance in particular Drosophilid lineages. PMID:27540774

Spatial distribution patterns of soil mite communities and their relationships with edaphic factors in a 30-year tillage cornfield in northeast China.

PubMed

Liu, Jie; Gao, Meixiang; Liu, Jinwen; Guo, Yuxi; Liu, Dong; Zhu, Xinyu; Wu, Donghui

2018-01-01

Spatial distribution is an important topic in community ecology and a key to understanding the structure and dynamics of populations and communities. However, the available information related to the spatial patterns of soil mite communities in long-term tillage agroecosystems remains insufficient. In this study, we examined the spatial patterns of soil mite communities to explain the spatial relationships between soil mite communities and soil parameters. Soil fauna were sampled three times (August, September and October 2015) at 121 locations arranged regularly within a 400 m × 400 m monitoring plot. Additionally, we estimated the physical and chemical parameters of the same sampling locations. The distribution patterns of the soil mite community and the edaphic parameters were analyzed using a range of geostatistical tools. Moran's I coefficient showed that, during each sampling period, the total abundance of the soil mite communities and the abundance of the dominant mite populations were spatially autocorrelated. The soil mite communities demonstrated clear patchy distribution patterns within the study plot. These patterns were sampling period-specific. Cross-semivariograms showed both negative and positive cross-correlations between soil mite communities and environmental factors. Mantel tests showed a significant and positive relationship between soil mite community and soil organic matter and soil pH only in August. This study demonstrated that in the cornfield, the soil mite distribution exhibited strong or moderate spatial dependence, and the mites formed patches with sizes less than one hundred meters. In addition, in this long-term tillage agroecosystem, soil factors had less influence on the observed pattern of soil mite communities. Further experiments that take into account human activity and spatial factors should be performed to study the factors that drive the spatial distribution of soil microarthropods.

Survival and reproductive rate of mites in relation to resistance of their barn swallow hosts.

PubMed

Møller, A P

2000-08-01

Parasite resistance may act via a number of different mechanisms that regulate or control the survival and the reproductive rate of parasites. Observations and experiments were used to test for effects of host resistance on parasite survival and rate of reproduction. Natural levels of infestation of barn swallow Hirundo rustica nests by the tropical fowl mite Ornithonyssus bursa were positively related to brood size, inversely related to the length of the outermost tail feathers of male nest owners (a secondary sexual character) and affected by time of reproduction by the host. A mite inoculation experiment, in which 50 adult mites were introduced into nests during the laying period of the host, was used to test for differential survival and reproduction of mites as a function of host resistance. The relationship between survival and reproduction of parasites, male tail length and host resistance was investigated. There was a negative relationship between mite numbers per nest after fledging of nestlings and male tail length. This relationship was mainly caused by a reduction in the number of mites in the first and second nymph stage with increasing tail length of male hosts, implying a reduction in rate of reproduction of mites. The proportion of mites that had recently fed was inversely related to tail length of male hosts. The proportion of nymph stages was positively related to the proportion of mites that had recently had a blood meal. Parasite resistance of barn swallows to the tropical fowl mite thus appeared to act through increased mortality rate of adult and nymph stages of mites, and through reduced reproductive rates of mites on resistant hosts. This is the first study demonstating a direct relationship between fitness components of a parasite and the expression of a secondary sexual character of a host.

Dehydration Stress Contributes to the Enhancement of Plant Defense Response and Mite Performance on Barley.

PubMed

Santamaria, M E; Diaz, Isabel; Martinez, Manuel

2018-01-01

Under natural conditions, plants suffer different stresses simultaneously or in a sequential way. At present, the combined effect of biotic and abiotic stressors is one of the most important threats to crop production. Understanding how plants deal with the panoply of potential stresses affecting them is crucial to develop biotechnological tools to protect plants. As well as for drought stress, the economic importance of the spider mite on agriculture is expected to increase due to climate change. Barley is a host of the polyphagous spider mite Tetranychus urticae and drought produces important yield losses. To obtain insights on the combined effect of drought and mite stresses on the defensive response of this cereal, we have analyzed the transcriptomic responses of barley plants subjected to dehydration (water-deficit) treatment, spider mite attack, or to the combined dehydration-spider mite stress. The expression patterns of mite-induced responsive genes included many jasmonic acid responsive genes and were quickly induced. In contrast, genes related to dehydration tolerance were later up-regulated. Besides, a higher up-regulation of mite-induced defenses was showed by the combined dehydration and mite treatment than by the individual mite stress. On the other hand, the performance of the mite in dehydration stressed and well-watered plants was tested. Despite the stronger defensive response in plants that suffer dehydration and mite stresses, the spider mite demonstrates a better performance under dehydration condition than in well-watered plants. These results highlight the complexity of the regulatory events leading to the response to a combination of stresses and emphasize the difficulties to predict their consequences on crop production.

Population Growth of Varroa destructor (Acari: Varroidae) in Colonies of Russian and Unselected Honey Bee (Hymenoptera: Apidae) Stocks as Related to Numbers of Foragers With Mites.

PubMed

DeGrandi-Hoffman, Gloria; Ahumada, Fabiana; Danka, Robert; Chambers, Mona; DeJong, Emily Watkins; Hidalgo, Geoff

2017-06-01

Varroa (Varroa destructor Anderson and Trueman) is an external parasite of honey bees (Apis mellifera L.) and a leading cause of colony losses worldwide. Varroa populations can be controlled with miticides, but mite-resistant stocks such as the Russian honey bee (RHB) also are available. Russian honey bee and other mite-resistant stocks limit Varroa population growth by affecting factors that contribute to mite reproduction. However, mite population growth is not entirely due to reproduction. Numbers of foragers with mites (FWM) entering and leaving hives also affect the growth of mite populations. If FWM significantly contribute to Varroa population growth, mite numbers in RHB colonies might not differ from unselected lines (USL). Foragers with mites were monitored at the entrances of RHB and USL hives from August to November, 2015, at two apiary sites. At site 1, RHB colonies had fewer FWM than USL and smaller phoretic mite populations. Russian honey bee also had fewer infested brood cells and lower percentages with Varroa offspring than USL. At site 2, FWM did not differ between RHB and USL, and phoretic mite populations were not significantly different. At both sites, there were sharp increases in phoretic mite populations from September to November that corresponded with increasing numbers of FWM. Under conditions where FWM populations are similar between RHB and USL, attributes that contribute to mite resistance in RHB may not keep Varroa population levels below that of USL. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by US Government employees and is in the public domain in the US.

Dehydration Stress Contributes to the Enhancement of Plant Defense Response and Mite Performance on Barley

PubMed Central

Santamaria, M. E.; Diaz, Isabel; Martinez, Manuel

2018-01-01

Under natural conditions, plants suffer different stresses simultaneously or in a sequential way. At present, the combined effect of biotic and abiotic stressors is one of the most important threats to crop production. Understanding how plants deal with the panoply of potential stresses affecting them is crucial to develop biotechnological tools to protect plants. As well as for drought stress, the economic importance of the spider mite on agriculture is expected to increase due to climate change. Barley is a host of the polyphagous spider mite Tetranychus urticae and drought produces important yield losses. To obtain insights on the combined effect of drought and mite stresses on the defensive response of this cereal, we have analyzed the transcriptomic responses of barley plants subjected to dehydration (water-deficit) treatment, spider mite attack, or to the combined dehydration-spider mite stress. The expression patterns of mite-induced responsive genes included many jasmonic acid responsive genes and were quickly induced. In contrast, genes related to dehydration tolerance were later up-regulated. Besides, a higher up-regulation of mite-induced defenses was showed by the combined dehydration and mite treatment than by the individual mite stress. On the other hand, the performance of the mite in dehydration stressed and well-watered plants was tested. Despite the stronger defensive response in plants that suffer dehydration and mite stresses, the spider mite demonstrates a better performance under dehydration condition than in well-watered plants. These results highlight the complexity of the regulatory events leading to the response to a combination of stresses and emphasize the difficulties to predict their consequences on crop production. PMID:29681917

Temporal changes in distribution, prevalence and intensity of northern fowl mite (Ornithonyssus sylviarum) parasitism in commercial caged laying hens, with a comprehensive economic analysis of parasite impact.

PubMed

Mullens, Bradley A; Owen, Jeb P; Kuney, Douglas R; Szijj, Coralie E; Klingler, Kimberly A

2009-03-09

Establishment and spread of Ornithonyssus sylviarum were documented through time on sentinel hens (50 per house of 28,000-30,000 hens) in the first egg production cycle of three large commercial flocks (12 houses) of white leghorn hens. Mites were controlled using acaricide, and the impacts of treatment on mite populations and economic performance were documented. Mite prevalence and intensity increased rapidly and in tandem for 4-8 weeks after infestation. Intensity declined due to immune system involvement, but prevalence remained high, and this would affect mite sampling plan use and development. Early treatment was more effective at controlling mites; 85% of light infestations were eliminated by a pesticide spray (Ravap), versus 24% of heavy infestations. Hens infested later developed lower peak mite intensities, and those mite populations declined more quickly than on hens infested earlier in life. Raw spatial association by distance indices (SADIE), incorporating both the intensity and distribution of mites within a house, were high from week-to-week within a hen house. Once adjusted spatially to reflect variable hen cohorts becoming infested asynchronously, this analysis showed the association index tended to rebound at intervals of 5-6 weeks after the hen immune system first suppressed them. Large, consistent mite differences in one flock (high vs. low infestation levels) showed the economic damage of mite parasitism (assessed by flock indexing) was very high in the initial stages of mite expansion. Unmitigated infestations overall reduced egg production (2.1-4.0%), individual egg weights (0.5-2.2%), and feed conversion efficiency (5.7%), causing a profit reduction of $0.07-0.10 per hen for a 10-week period. Asynchronous infestation patterns among pesticide-treated hens may have contributed to a lack of apparent flock-level economic effects later in the production cycle. Individual egg weights differed with mite loads periodically, but could be either higher or lower, depending on circumstances and interactions with hen weight. Individual hen weight gains were depressed by high/moderate mite loads, but the heavier hens in a flock harbored more mites. This led to compensatory weight gains after mites declined. Tradeoffs between resource allocation to body growth or production versus immune system function appeared to be operating during the early and most damaging mite infestation period, when high egg production was beginning and the hens were gaining weight. The results were related to other studies of mite impact on domestic hens and to wild bird-ectoparasite studies. Much of the mite economic damage probably is due to engaging and maintaining the immune response.

A review of the effects of impermeable bedding encasements on dust-mite allergen exposure and bronchial hyper-responsiveness in dust-mite-sensitized patients.

PubMed

Recer, G M

2004-02-01

Sensitization and exposure to dust-mite antigens are causative factors in the development and exacerbation of asthma. Impermeable bedding encasements are considered a first-line treatment to reduce dust-mite antigen exposure in clinical asthma-management guidelines. Public-health recommendations for environmental asthma treatments should be based on the weight of evidence supporting the reliability of environmental interventions so that uncertainties regarding their effectiveness can be accurately communicated to patients, and so that limited public-health resources can be most effectively utilized. To evaluate the strength of a clinical-trial evidence supporting the efficacy of bedding encasements as an asthma treatment. A narrative review was conducted of all clinical trials involving bedding encasement for the treatment of asthma. Collective statistical analyses were also performed to characterize the quantitative effect of bedding encasement on dust-mite allergen exposure and bronchial hyper-responsiveness (BHR) when used by asthma patients. Over 30 clinical trials were reviewed. Of those studies reporting adequate exposure and BHR results, four reported significant reduction in dust-mite allergen exposure and concomitant BHR reduction in active-treatment groups using bedding encasements. In 10 studies, mite-allergen exposure was reportedly decreased during the study, but BHR was not changed in the active-treatment group or was reduced to a similar degree in the active-treatment and control groups. Five other studies reported a lack of significant effect of the intervention on exposure and BHR. Collective paired analyses found that the effect of bedding encasement on allergen exposure and BHR tended toward only a modest, non-significant improvement. Collectively, effects of bedding encasement on BHR and dust-mite allergen exposure were modestly correlated only when the baseline exposure was above 2 microg Type 1 antigen per gram settled dust. Although bedding encasement might be an effective asthma treatment under some conditions, when implemented in clinical trials by asthma patients, its effectiveness is inconsistent and appears to be, at best, modest. Therefore, its significance as a reliable asthma management modality for any individual asthma patient is uncertain. Where resource constraints are significant, targeting the use of variably effective interventions such as bedding encasements toward those patient sub-populations most likely to derive substantial benefit may gain the largest net public-health benefit.

Faunal analysis of chigger mites (Acari: Prostigmata) on small mammals in Yunnan province, southwest China.

PubMed

Peng, Pei-Ying; Guo, Xian-Guo; Ren, Tian-Guang; Song, Wen-Yu

2015-08-01

This paper studied the species diversity and fauna distribution of chigger mites on small mammals in Yunnan province, southwest Yunnan. In total, 120,138 individuals of chigger mites were collected from 13,760 individual small mammals, and these mites were identified as comprising two families, 26 genera, and 274 species. Of the five zoogeographical subregions, the mite species diversity in subregions I and II was higher than that in subregions III, IV, and V. Four mite species (Leptotrombidium scutellare, Leptotrombidium sinicum, Leptotrombidium deliense, and Helenicula simena) were the most dominant species in the whole province. Several vector species of chigger mites co-existed in Yunnan, and L. deliense (a main vector of scrub typhus in China) was mainly distributed in subregions IV and V with lower latitude and average altitude whereas L. scutellare (also a main vector in China) was mainly distributed in subregions I, II, and III with higher latitude and average altitude. Some geographically widely distributed mite species were also the mites with wide host ranges and low host specificity. The dominant mite species and their clustering tendency in the dendrogram of hierarchical clustering analysis were highly in accordance with the zoogeographical divisions. The species diversity of chigger mites showed a parabolic tendency from the low altitude (<500 m) to the high altitude (>3,500 m) along the vertical gradients and reached the highest value in the middle altitude regions in 2,000-2,500 m. The highest species diversity of the mites and their small mammal hosts happened in the regions around the Hengduan Mountains, which is a hotspot of biodiversity in Asia continent. The host and its sample size, geographical scope, landscape, topography, and some other factors comprehensively influence the species diversity and faunal distribution of chigger mites. A systematic field investigation with a wide geographical scope and large host sample is strongly recommended in the fauna study of chigger mites and other ectoparasites.

Pyroglyphid mites as a source of work-related allergens.

PubMed

Macan, Jelena; Kanceljak-Macan, Božica; Milković-Kraus, Sanja

2012-01-01

Pyroglyphid mites are primarily associated with allergen exposure at home; hence the name house dust mites. However, we have found numerous studies reporting pyroglyhid mite levels in public and occupational settings. This review presents the findings of house dust mite allergens (family Pyroglyphidae, species Dermatophagoides) as potential work-related risk factors and proposes occupations at risk of house dust mite-related diseases. Pyroglyphid mites or their allergens are found in various workplaces, but clinically relevant exposures have been observed in hotels, cinemas, schools, day-care centres, libraries, public transportation (buses, trains, taxies, and airplanes), fishing-boats, submarines, poultry farms, and churches. Here we propose a classification of occupational risk as low (occasional exposure to mite allergen levels up to 2 μg g(-1)), moderate (exposure between 2 μg g(-1) and 10 μg g(-1)), and high (exposure >10 μg g(-1)). The classification of risk should include factors relevant for indoor mite population (climate, building characteristics, and cleaning schedule). To avoid development or aggravation of allergies associated with exposure to house dust mites at work, occupational physicians should assess exposure risk at work, propose proper protection, provide vocational guidance to persons at risk and conduct pre-employment and periodic examinations to diagnose new allergy cases. Protection at work should aim to control dust mite levels at work. Measures may include proper interior design and regular cleaning and building maintenance.

The effect of sub-floor heating on house-dust-mite populations on floors and in furniture.

PubMed

de Boer, Rob

2003-01-01

It is well known that dehydrating conditions for house dust mites can be created by simply raising the temperature, causing loss of body water and eventually death. Thus, it can be expected that conditions for dust mites are less favourable on floors supplied with sub-floor heating. This was examined in a study of 16 houses with sub-floor heating and 21 without. The pattern of changes in air humidity and temperature on the floors was investigated and compared to known data of the tolerance of dust mites. Also the resident mite populations were compared. Floors with sub-floor heating had, on average, fewer mites, but the difference with unheated floors was small. It was remarkable that mite numbers were also lower in upholstered furniture. Another important observation was that some houses with sub-floor heating had high mite numbers, indicating that this type of heating is compatible with a thriving mite population. Temperature and humidity conditions of heated floors may allow mites not only to survive, but also to remain active in winter. A moderate increase in temperature, a moderate decrease in (absolute) air humidity, or a combination of both, will suffice to keep the humidity all winter below the Critical Equilibrium Humidity, the level of air humidity that is critical for mite growth and reproduction, hence for allergen production. However, it is argued that measures to suppress allergen production by house dust mites are likely to be far more effective if taken in summer rather than in winter.

Dynamics of house dust mite transfer in modern clothing fabrics.

PubMed

Clarke, David; Burke, Daniel; Gormally, Michael; Byrne, Miriam

2015-04-01

Clothing is largely presumed as being the mechanism by which house dust mites are distributed among locations in homes, yet little research to date has investigated the capacity with which various clothing fabric types serve as vectors for their accumulation and dispersal. Although previous research has indicated that car seats provide a habitat for mite populations, dynamics involved in the transfer of mites to clothing via car seat material is still unknown. To investigate the dynamics involved in the transfer of house dust mites from car seat material to modern clothing fabrics. A total of 480 samples of car seat material were seeded with mites and subjected to contact with plain woven cotton, denim, and fleece. Contact forces equivalent to the mass of a typical adult and child were administered for different durations of contact. Mean transfer efficiencies of mites from car seat material to receiving clothing fabrics ranged from 7.2% to 19.1%. Fabric type, mite condition (live or dead), and the force applied all revealed a significant effect (P < .001 for each variable) on the transfer efficiency of house dust mites from seeded material to receiving fabrics, whereas duration of contact revealed no effect (P = .20). In particular, mean numbers of mites transferred to fleece (compared with denim and plain woven cotton) were greater for each treatment. These findings indicate that clothing type can have important implications for the colonization of other biotopes by house dust mites, with potential for affecting an individuals' personal exposure to dust mite allergens. Copyright © 2015 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

The effect of queen pheromone status on Varroa mite removal from honey bee colonies with different grooming ability.

PubMed

Bahreini, Rassol; Currie, Robert W

2015-07-01

The objective of this study was to assess the effects of honey bees (Apis mellifera L.) with different grooming ability and queen pheromone status on mortality rates of Varroa mites (Varroa destructor Anderson and Trueman), mite damage, and mortality rates of honey bees. Twenty-four small queenless colonies containing either stock selected for high rates of mite removal (n = 12) or unselected stock (n = 12) were maintained under constant darkness at 5 °C. Colonies were randomly assigned to be treated with one of three queen pheromone status treatments: (1) caged, mated queen, (2) a synthetic queen mandibular pheromone lure (QMP), or (3) queenless with no queen substitute. The results showed overall mite mortality rate was greater in stock selected for grooming than in unselected stock. There was a short term transitory increase in bee mortality rates in selected stock when compared to unselected stock. The presence of queen pheromone from either caged, mated queens or QMP enhanced mite removal from clusters of bees relative to queenless colonies over short periods of time and increased the variation in mite mortality over time relative to colonies without queen pheromone, but did not affect the proportion of damaged mites. The effects of source of bees on mite damage varied with time but damage to mites was not reliably related to mite mortality. In conclusion, this study showed differential mite removal of different stocks was possible under low temperature. Queen status should be considered when designing experiments using bioassays for grooming response.

A feeding protocol for delivery of agents to assess development in Varroa mites

PubMed Central

2017-01-01

A novel feeding protocol for delivery of bio-active agents to Varroa mites was developed by providing mites with honey bee larva hemolymph supplemented with cultured insect cells and selected materials delivered on a fibrous cotton substrate. Mites were starved, fed on treated hemolymph to deliver selected agents and then returned to bee larvae. Transcript levels of two reference genes, actin and glyceraldehyde 3-phosphate dehydrogenase (GAPDH), as well as for nine selected genes involved in reproductive processes showed that the starvation and feeding protocol periods did not pose a high level of stress to the mites as transcript levels remained comparable between phoretic mites and those completing the protocol. The feeding protocol was used to deliver molecules such as hormone analogs or plasmids. Mites fed with Tebufenozide, an ecdysone analog, had higher transcript levels of shade than untreated or solvent treated mites. In order to extend this feeding protocol, cultured insect cells were incorporated to a final ratio of 1 part cells and 2 parts hemolymph. Although supplementation with Bombyx mori Bm5 cells increased the amount of hemolymph consumed per mite, there was a significant decrease in the percentage of mites that fed and survived. On the other hand, Drosophila melanogaster S2 cells reduced significantly the percentage of mites that fed and survived as well as the amount of hemolymph consumed. The feeding protocol provides a dynamic platform with which to challenge the Varroa mite to establish efficacy of control agents for this devastating honey bee pest. PMID:28448606

A comparison of the reproductive ability of Varroa destructor (Mesostigmata:Varroidae) in worker and drone brood of Africanized honey bees (Apis mellifera).

PubMed

Calderón, Rafael A; Zamora, Luis G; Van Veen, Johan W; Quesada, Mariela V

2007-01-01

Colony infestation by the parasitic mite, Varroa destructor is one of the most serious problems for beekeeping worldwide. In order to reproduce varroa females, enter worker or drone brood shortly before the cell is sealed. To test the hypothesis that, due to the preference of mites to invade drone brood to reproduce, a high proportion of the mite reproduction should occur in drone cells, a comparative study of mite reproductive rate in worker and drone brood of Africanized honey bees (AHB) was done for 370 mites. After determining the number, developmental stage and sex of the offspring in worker cells, the foundress female mite was immediately transferred into an uninfested drone cell. Mite fertility in single infested worker and drone brood cells was 76.5 and 79.3%, respectively. There was no difference between the groups (X(2)= 0.78, P = 0.37). However, one of the most significant differences in mite reproduction was the higher percentage of mites producing viable offspring (cells that contain one live adult male and at least one adult female mite) in drone cells (38.1%) compared to worker cells (13.8%) (X(2)= 55.4, P < 0.01). Furthermore, a high level of immature offspring occurred in worker cells and not in drone cells (X(2)= 69, P < 0.01). Although no differences were found in the percentage of non-reproducing mites, more than 74% (n = 85) of the mites that did not reproduce in worker brood, produced offspring when they were transferred to drone brood.

Compatibility of the entomopathogenic fungus Beauveria bassiana with flufenoxuron and azadirachtin against Tetranychus urticae.

PubMed

Hernández, M M; Martínez-Villar, E; Peace, C; Pérez-Moreno, I; Marco, V

2012-12-01

Laboratory studies were developed to evaluate the compatibility of flufenoxuron and azadirachtin with Beauveria bassiana against Tetranychus urticae larvae along with the required Probit analysis of the involved chemicals on all of the life stages of this mite. Flufenoxuron displayed parallel regression lines for the mortality of eggs, deutonymphs and adults. Larvae and protonymphs were the most susceptible life stages. Protonymphs were 35 times more sensitive than eggs and adults. Azadirachtin gave equal mortality on proto- and deutonymphs. The response of eggs and adults was equivalent when treated with azadirachtin. The regression lines for proto- and deutonymphs were parallel to those of adults and eggs yet three times more sensitive. The effects of separate combinations of the entomopathogenic fungus Beauveria bassiana at its LC(20) with flufenoxuron and azadirachtin at their corresponding LC(40) were evaluated on mite larvae. The application of flufenoxuron with B. bassiana revealed a clear synergy. While the combination of azadirachtin and B. bassiana had an additive effect. These combinations with B. bassiana could improve mite control by contributing to a decline in the likelihood of resistance so often described in the literature.

Laboratory tests for controlling poultry red mites (Dermanyssus gallinae) with predatory mites in small 'laying hen' cages.

PubMed

Lesna, Izabela; Sabelis, Maurice W; van Niekerk, Thea G C M; Komdeur, Jan

2012-12-01

To assess their potential to control poultry red mites (Dermanyssus gallinae), we tested selected predaceous mites (Androlaelaps casalis and Stratiolaelaps scimitus) that occur naturally in wild bird nests or sometimes spontaneously invade poultry houses. This was done under laboratory conditions in cages, each with 2-3 laying hens, initially 300 poultry red mites and later the release of 1,000 predators. These small-scale tests were designed to prevent mite escape from the cages and they were carried out in three replicates at each of three temperature regimes: 26, 30 (constant day and night) and 33-25 °C (day-night cycle). After 6 weeks total population sizes of poultry red mites and predatory mites were assessed. For the temperature regimes of 26 and 33/25 °C S. scimitus reduced the poultry red mite population relative to the control experiments by a factor 3 and 30, respectively, and A. casalis by a factor of 18 and 55, respectively. At 30 °C the predators had less effect on red mites, with a reduction of 1.3-fold for S. scimitus and 5.6-fold for A. casalis. This possibly reflected hen manure condition or an effect of other invertebrates in the hen feed. Poultry red mite control was not negatively affected by temperatures as high as 33 °C and was always better in trials with A. casalis than in those with S. scimitus. In none of the experiments predators managed to eradicate the population of poultry red mites. This may be due to a prey refuge effect since most predatory mites were found in and around the manure tray at the bottom of the cage, whereas most poultry red mites were found higher up in the cage (i.e. on the walls, the cover, the perch, the nest box and the food box). The efficacy of applying predatory mites in the poultry industry may be promoted by reducing this refuge effect, boosting predatory mite populations using alternative prey and prolonged predator release devices. Biocontrol success, however, will strongly depend on how the poultry is housed in practice (free range, cage or aviary systems) and on which chemicals are applied to disinfect poultry houses and to control other pests.

[Dust mites as occupational allergens in two bakeries of La Habana, Cuba].

PubMed

Fernández-Duro, Bárbara I; Alvarez-Castelló, Mirta; Mateo-Morejón, Mayteé; Luis-Rodríguez, Bárbara; Labrada-Rosado, Alexis

2014-01-01

Occupational allergies are becoming more frequent. The allergens present in the working environment of bakeries, such as mites, are not well identified despite being known risk factors of respiratory diseases. To isolate and identify the species of mites present in two bakeries in La Habana, Cuba, with high sensitization of mites on their workers. A descriptive study was done in which samples were taken by tripled from potential sources of mites in bakeries -as flourin use, spills of wheat on the floors, wheat flour stored in sealed bags, sugar, yeast, granulated baker- that were processed, according to the method of flotation of Hart and Fain (1987) to isolate, identify and count the mites present. Mites were found in samples of wheat flourin use, spills on the floorsand in the wheat flourstored in sealed bags. The species identified were Blomia tropicalis (70%), Tyrophagus putrescentiae (20%) and to a lesser degree Dermatophagoides pteronyssinus and Dermatophagoides siboney. There is a high exposure to house dust mites, particularly to store mites, which constitute a risk factor of occupational allergy to consider.

House-dust mites in our homes are a contamination from outdoor sources.

PubMed

Hallas, Thorkil E

2010-05-01

Avoidance advices for house-dust mite sensitized persons are currently based upon the idea, that the mites (Dermatophagoides spp.) are part of the indoor fauna. A closer look at development stages in the house-dust samples shows, however, that only the mites' active stages are present there and that the stages between them, the inactive moulting stages, are absent. Therefore the mites probably do not carry out their life cycles in our dwellings, but are more likely contaminations from the open. Findings of low level concentrations can be explained by mites coming from outdoors and sedimented in accordance with known physical laws. The occasional finding of higher concentrations is the result of synchronized populations of the mites developing outdoors and being passively transported into our homes by wind and dust. The hypothesis explains why we find mites in our homes but nonetheless have no effect of avoidance measures. The verification of the entire hypothesis or part of it may have great impact on the management of the disease house-dust mite allergy.

Minimal Pruning and Reduced Plant Protection Promote Predatory Mites in Grapevine

PubMed Central

Pennington, Theresa; Kraus, Christian; Alakina, Ekatarina; Entling, Martin H.; Hoffmann, Christoph

2017-01-01

Improving natural pest control by promoting high densities of predatory mites (Acari: Phytoseiidae) is an effective way to prevent damage by pest mites (e.g., Eriophyidae, Tetranychidae) and other arthropod taxa that can cause serious damage to vineyards. Here, we investigate the influence of innovative management on predatory mite densities. We compare (i) full versus reduced fungicide applications and (ii) minimal pruning versus a traditional trellis pruning system in four fungus-resistant grapevine varieties. As predatory mites also feed on fungus mycelium, we assessed fungal infection of grapevine leaves in the experimental vineyard. Predatory mites were significantly more abundant in both minimal pruning and under reduced plant protection. Increases in predatory mites appeared to be independent of fungal infection, suggesting mostly direct effects of reduced fungicides and minimal pruning. In contrast to predatory mites, pest mites did not increase under innovative management. Thus, conditions for natural pest control are improved in fungus-resistant grapevines and under minimal pruning, which adds to other advantages such as environmental safety and reduced production cost. PMID:28820436

Effect of acaricidal components isolated from lettuce (Lactuca sativa) on carmine spider mite (Tetranychus cinnabarinus Boisd.).

PubMed

Li, M; Zhang, Y; Ding, W; Luo, J; Li, S; Zhang, Q

2018-06-01

This study aimed to evaluate the acaricidal activity of lettuce (Lactuca sativa) extracts against carmine spider mites (Tetranychus cinnabarinus Boisd.) and isolate the acaricidal components. Acaricidal activities of lettuce extracts isolated from different parts (the leaf, root and seed) using various solvents (petroleum ether, acetone and methanol) were evaluated with slide-dip bioassay and relatively high median lethal concentration (LC50) values were detected. Acetone extracts of lettuce leaves harvested in July and September were fractionated and isolated with silica gel and thin-layer chromatography. Consequently, acetone extracts of lettuce leaves harvested in July exhibited higher acaricidal activity than those harvested in September, with an LC50 value of 0.268 mg ml-1 at 72 h post-treatment. A total of 27 fractions were obtained from the acetone extract of lettuce leaves harvested in July, and mite mortalities with the 11th and 12th fractions were higher than those with the other 25 fractions (LC50: 0.751 and 1.258 mg ml-1 at 48 h post-treatment, respectively). Subsequently, active acaricidal components of the 11th fraction were identified by infrared, nuclear magnetic resonance and liquid chromatography/mass spectrometry. Five components were isolated from the 11th fraction, with components 11-a and 11-b showing relatively high acaricidal activities (LC50: 0.288 and 0.114 mg ml-1 at 48 h post-treatment, respectively). Component 11-a was identified as β-sitosterol. In conclusion, acetone extracts of lettuce leaves harvested in July might be used as a novel phytogenic acaricide to control mites.

Indoor mite allergens in patients with respiratory allergy living in Porto, Portugal.

PubMed

Plácido, J L; Cuesta, C; Delgado, L; da Silva, J P; Miranda, M; Ventas, P; Vaz, M

1996-09-01

We investigated the levels of mite allergens (Der p 1, Der f 1, Der 2, and Lep d 1) in dust samples from the homes of 59 patients with asthma, 36 sensitized to house-dust mites (HDM) and 23 to grass pollen (controls), living in Porto, northern Portugal. The relationship between exposure and sensitization to HDM and the influence of housing conditions on mite-allergen levels were also evaluated. Der p 1 (median 9.2 micrograms/g) and Der 2 (4.6 micrograms/g) were the main allergens, while Der f 1 and Lep d 1 levels were always < 1 microgram/g dust and undetectable in 11% and 47% of samples, respectively. All HDM-sensitized asthmatics were exposed to Der p 1 levels > 2 micrograms/g and their homes contained significantly higher levels of Der p 1 (median 12.5 vs 6.4 micrograms/g; P = 0.008) and Der 2 (6.2 vs 3.0 micrograms/g; P = 0.004) when compared to the control group. A significant correlation was observed between the exposure to Der p 1 and the wheal area at skin testing with the Dermatophagoides pteronyssinus (Dp) extract (P = 0.01) as well as with serum specific IgE levels to Dp (P = 0.03). Patients with higher levels of serum specific IgE (> or = 17.5 HRU/ml) were also more frequently exposed to Der p 1 levels > or = 10 micrograms/g (P = 0.002). Old homes, presence of carpets, and signs of dampness were conditions associated with significantly higher levels of mite allergens. In conclusion, we found high levels of Der p 1 and Der 2 particularly in the homes of HDM-sensitized patients and we confirm the relationship between exposure and sensitization to HDM, assessed by both in vivo and in vitro methods. In additional to a favorable outdoor climate, we found in our region housing conditions propitious to mite growth, suggesting that specific geographic characteristics must also be taken into account for the correct planning of mite-avoidance measures.

Characterization of the complete mitochondrial genome of the storage mite pest Tyrophagus longior (Gervais) (Acari: Acaridae) and comparative mitogenomic analysis of four acarid mites.

PubMed

Yang, Banghe; Li, Chaopin

2016-02-01

Mites of the genus Tyrophagus are economically important polyphagous pest commonly living on stored products and also responsible for allergic reactions to humans. Complete mitochondrial genomes (mitogenomes) and the gene features therein are widely used as molecular markers in the study of population genetics, phylogenetics as well as molecular evolution. However, scarcity on the sequence data has greatly impeded the studies in these areas pertaining to the Acari (mites and ticks). Information on the Tyrophagus mitogenomes is quite critical for phylogenetic evaluation and molecular evolution of the mitogenomes within Acariformes. Herein, we reported the complete mitogenome of the allergenic acarid storage mite Tyrophagus longior (Astigmata: Acaridae), an important member of stored food pests, and compared with those of other three acarid mites. The complete mitogenome of T. longior was a circular molecule of 13,271 bp. Unexpectedly, only 19 transfer RNA genes (tRNAs) were present, lacking trnF, trnS1 and trnQ. Furthermore, it also contained 13 protein-coding genes (PCGs) and 2 genes for rRNA (rrnS and rrnL) commonly detected in metazoans. The four mitogenomes displayed similar characteristics with respect to the gene content, nucleotide comparison, and codon usages. Yet, the gene order of T. longior was different from that in other Acari. The J-strands of the four mitogenomes possessed high A+T content (67.4-70.0%), and exhibited positive GC-skews and negative AT-skews. Most inferred tRNAs of T. longior were extremely truncated, lacking either a D- or T-arm, as found in other acarid mites. In T. longior mitogenome the A+T-rich region was just 50 bp in length and can be folded as a stable stem-loop structure, whereas in the region some structures of microsatellite-like (AT)n and palindromic sequences was not present. Besides, reconstructing of the phylogenetic relationship based on concatenated amino acid sequences of 13 PCGs supported that monophyly of the family Acaridae and the order Astigmata, to which the former belongs. Our results were consistent with the traditional classifications. Copyright © 2015 Elsevier B.V. All rights reserved.

What's eating you? Cheyletiella mites.

PubMed

Reynolds, H Harris; Elston, Dirk M

2017-05-01

Cheyletiella are nonburrowing mites commonly found on rabbits, dogs, and cats. The mites have been known to cause disease in humans, ranging from mild dermatitis to more severe illness with systemic symptoms. Because these mites do not complete any part of their life cycle in humans, diagnosis can be challenging. Herein, we review various clinical presentations associated with Cheyletiella mites as well as diagnostic techniques and treatment options for both humans and animals.

Feather and nest mites of two common resident birds in two ecologically different Egyptian governorates.

PubMed

Morsy, T A; Mazyad, S A; Younis, M S

1999-08-01

The study of the role played by birds in the distribution of various bacterial, viral and parasitic infections is increasingly from year to year, taking into consideration the flying ability of birds and their migration for food and vital processes. Two of the common Egyptian resident birds, house sparrow (Passer d. niloticus) and laughing dove (Streptopelia s. aegyptiaca) were chosen to study their mite fauna. The overall mite index was 4.74 on the house sparrow and 7.22 on the laughing dove. As to mites, a total of 31 species belonging to 23 genera, 17 families and 3 suborders were collected. The common mites on both types of birds were 22 species. Three species only on house sparrow, and six species only on laughing dove. The house sparrow served host for 25 mite species and the laughing dove served host for 28 mite species. The infestation rates of mites on house sparrow ranged between 1.11% to 23.33% and 0.21% to 34.54% in Sharkia and Qalyobia governorates respectively. For laughing dove, the mite infestation rates ranged between 0.82% to 50% and 3.45% to 55.17% for both governorates respectively. Some of the collected mites have medical and/or veterinary importance. The whole results were discussed.

Induced plant-defenses suppress herbivore reproduction but also constrain predation of their offspring.

PubMed

Ataide, Livia M S; Pappas, Maria L; Schimmel, Bernardus C J; Lopez-Orenes, Antonio; Alba, Juan M; Duarte, Marcus V A; Pallini, Angelo; Schuurink, Robert C; Kant, Merijn R

2016-11-01

Inducible anti-herbivore defenses in plants are predominantly regulated by jasmonic acid (JA). On tomato plants, most genotypes of the herbivorous generalist spider mite Tetranychus urticae induce JA defenses and perform poorly on it, whereas the Solanaceae specialist Tetranychus evansi, who suppresses JA defenses, performs well on it. We asked to which extent these spider mites and the predatory mite Phytoseiulus longipes preying on these spider mites eggs are affected by induced JA-defenses. By artificially inducing the JA-response of the tomato JA-biosynthesis mutant def-1 using exogenous JA and isoleucine (Ile), we first established the relationship between endogenous JA-Ile-levels and the reproductive performance of spider mites. For both mite species we observed that they produced more eggs when levels of JA-Ile were low. Subsequently, we allowed predatory mites to prey on spider mite-eggs derived from wild-type tomato plants, def-1 and JA-Ile-treated def-1 and observed that they preferred, and consumed more, eggs produced on tomato plants with weak JA defenses. However, predatory mite oviposition was similar across treatments. Our results show that induced JA-responses negatively affect spider mite performance, but positively affect the survival of their offspring by constraining egg-predation. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Geostatistics as a tool to study mite dispersion in physic nut plantations.

PubMed

Rosado, J F; Picanço, M C; Sarmento, R A; Pereira, R M; Pedro-Neto, M; Galdino, T V S; de Sousa Saraiva, A; Erasmo, E A L

2015-08-01

Spatial distribution studies in pest management identify the locations where pest attacks on crops are most severe, enabling us to understand and predict the movement of such pests. Studies on the spatial distribution of two mite species, however, are rather scarce. The mites Polyphagotarsonemus latus and Tetranychus bastosi are the major pests affecting physic nut plantations (Jatropha curcas). Therefore, the objective of this study was to measure the spatial distributions of P. latus and T. bastosi in the physic nut plantations. Mite densities were monitored over 2 years in two different plantations. Sample locations were georeferenced. The experimental data were analyzed using geostatistical analyses. The total mite density was found to be higher when only one species was present (T. bastosi). When both the mite species were found in the same plantation, their peak densities occurred at different times. These mites, however, exhibited uniform spatial distribution when found at extreme densities (low or high). However, the mites showed an aggregated distribution in intermediate densities. Mite spatial distribution models were isotropic. Mite colonization commenced at the periphery of the areas under study, whereas the high-density patches extended until they reached 30 m in diameter. This has not been reported for J. curcas plants before.

House dust-mite allergen exposure is associated with serum specific IgE but not with respiratory outcomes.

PubMed

Bakolis, I; Heinrich, J; Zock, J P; Norbäck, D; Svanes, C; Chen, C M; Accordini, S; Verlato, G; Olivieri, M; Jarvis, D

2015-06-01

Exposure to house dust has been associated with asthma in adults, and this is commonly interpreted as a direct immunologic response to dust-mite allergens in those who are IgE sensitized to house dust-mite. Mattress house dust-mite concentrations were measured in a population-based sample of 2890 adults aged between 27 and 56 years living in 22 centers in 10 countries. Generalized linear mixed models were employed to explore the association of respiratory symptoms with house dust-mite concentrations, adjusting for individual and household confounders. There was no overall association of respiratory outcomes with measured house dust-mite concentrations, even in those who reported they had symptoms on exposure to dust and those who had physician-diagnosed asthma. However, there was a positive association of high serum specific IgE levels to HDM (>3.5 kUA /l) with mattress house dust-mite concentrations and a negative association of sensitization to cat with increasing house dust-mite concentrations. In conclusion, there was no evidence that respiratory symptoms in adults were associated with exposure to house dust-mite allergen in the mattress, but an association of house mite with strong sensitization was observed. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Mitochondrial genome evolution and tRNA truncation in Acariformes mites: new evidence from eriophyoid mites

PubMed Central

Xue, Xiao-Feng; Guo, Jing-Feng; Dong, Yan; Hong, Xiao-Yue; Shao, Renfu

2016-01-01

The subclass Acari (mites and ticks) comprises two super-orders: Acariformes and Parasitiformes. Most species of the Parasitiformes known retained the ancestral pattern of mitochondrial (mt) gene arrangement of arthropods, and their mt tRNAs have the typical cloverleaf structure. All of the species of the Acariformes known, however, have rearranged mt genomes and truncated mt tRNAs. We sequenced the mt genomes of two species of Eriophyoidea: Phyllocoptes taishanensis and Epitrimerus sabinae. The mt genomes of P. taishanensis and E. sabinae are 13,475 bp and 13,531 bp, respectively, are circular and contain the 37 genes typical of animals; most mt tRNAs are highly truncated in both mites. On the other hand, these two eriophyoid mites have the least rearranged mt genomes seen in the Acariformes. Comparison between eriophyoid mites and other Aacariformes mites showed that: 1) the most recent common ancestor of Acariformes mites retained the ancestral pattern of mt gene arrangement of arthropods with slight modifications; 2) truncation of tRNAs for cysteine, phenylalanine and histidine occurred once in the most recent common ancestor of Acariformes mites whereas truncation of other tRNAs occurred multiple times; and 3) the placement of eriophyoid mites in the order Trombidiformes needs to be reviewed. PMID:26732998

Protocols for the delivery of small molecules to the two-spotted spider mite, Tetranychus urticae

PubMed Central

Nunes, Maria Andreia; Zhurov, Vladimir; Dermauw, Wannes; Osakabe, Masahiro; Van Leeuwen, Thomas; Grbic, Miodrag

2017-01-01

The two-spotted spider mite, Tetranychus urticae, is a chelicerate herbivore with an extremely wide host range and an extraordinary ability to develop pesticide resistance. Due to its responsiveness to natural and synthetic xenobiotics, the spider mite is becoming a prime pest herbivore model for studies of the evolution of host range, plant-herbivore interactions and mechanisms of xenobiotic resistance. The spider mite genome has been sequenced and its transcriptional responses to developmental and various biotic and abiotic cues have been documented. However, to identify biological and evolutionary roles of T. urticae genes and proteins, it is necessary to develop methods for the efficient manipulation of mite gene function or protein activity. Here, we describe protocols developed for the delivery of small molecules into spider mites. Starting with mite maintenance and the preparation of the experimental mite populations of developmentally synchronized larvae and adults, we describe 3 methods for delivery of small molecules including artificial diet, leaf coating, and soaking. The presented results define critical steps in these methods and demonstrate that they can successfully deliver tracer dyes into mites. Described protocols provide guidelines for high-throughput setups for delivery of experimental compounds that could be used in reverse genetics platforms to modulate gene expression or protein activity, or for screens focused on discovery of new molecules for mite control. In addition, described protocols could be adapted for other Tetranychidae and related species of economic importance such as Varroa, dust and poultry mites. PMID:28686745

Are Dispersal Mechanisms Changing the Host-Parasite Relationship and Increasing the Virulence of Varroa destructor (Mesostigmata: Varroidae) in Managed Honey Bee (Hymenoptera: Apidae) Colonies?

PubMed

DeGrandi-Hoffman, Gloria; Ahumada, Fabiana; Graham, Henry

2017-08-01

Varroa (Varroa destructor Anderson and Trueman) are a serious pest of European honey bees (Apis mellifera L.), and difficult to control in managed colonies. In our 11-mo longitudinal study, we applied multiple miticide treatments, yet mite numbers remained high and colony losses exceeded 55%. High mortality from varroa in managed apiaries is a departure from the effects of the mite in feral colonies where bees and varroa can coexist. Differences in mite survival strategies and dispersal mechanisms may be contributing factors. In feral colonies, mites can disperse through swarming. In managed apiaries, where swarming is reduced, mites disperse on foragers robbing or drifting from infested hives. Using a honey bee-varroa population model, we show that yearly swarming curtails varroa population growth, enabling colony survival for >5 yr. Without swarming, colonies collapsed by the third year. To disperse, varroa must attach to foragers that then enter other hives. We hypothesize that stress from parasitism and virus infection combined with effects that viruses have on cognitive function may contribute to forager drift and mite and virus dispersal. We also hypothesize that drifting foragers with mites can measurably increase mite populations. Simulations initialized with field data indicate that low levels of drifting foragers with mites can create sharp increases in mite populations in the fall and heavily infested colonies in the spring. We suggest new research directions to investigate factors leading to mite dispersal on foragers, and mite management strategies with consideration of varroa as a migratory pest. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by US Government employees and is in the public domain in the US.

Cheyletus eruditus (taurrus): an effective candidate for the biological control of the snake mite (Ophionyssus natricis).

PubMed

Schilliger, Lionel H; Morel, Damien; Bonwitt, Jesse H; Marquis, Olivier

2013-09-01

The most commonly encountered ectoparasite in captive snakes is the hematophagous snake mite (Ophionyssus natricis). Infected snakes often exhibit lethargy, dysecdysis, pruritus, crusting dermatitis (sometimes progressing to abscesses), and behavioral changes (increased bathing time, rubbing against objects). Anemia and septicemia are occasional complications. Eliminating snake mites from a collection is frustrating. Insecticidal and acaricidal compounds used in mammals can be used against O. natricis infestation in reptiles, but they all are potentially neurotoxic to reptiles. The use of a biological agent to control the snake mite was first developed by using the predatory mites Hypoaspis miles and Hypoaspis aculeifer. However, no data are available regarding the potential of these mites to control O. natricis. Furthermore, the survival and predatory behavior of H. aculeifer and H. miles decreases above 28 degrees C, which is the lower value of the optimal temperature zone range required for rearing snakes. The aim of this study is to identify the ability of the predatory mite Cheyletus eruditus to control O. natricis. In the first experiment, 125 O. natricis mites where placed in separate plastic tubes together with the same number of C. eruditus mites. After 48 hr, the survival rate of snake mites was 6% compared with 92% in the control group (n = 125, P < 0,001). In the second experiment, 11 infested (average of 13 O. natricis per snake) ball pythons, with an average of 13 O. natricis per individual, were placed in separate cages with 1,000 C. eruditus mites + vermiculite After 15 days, only an average of two mites per snake remained, compared with 48 per snake in the control group (t-test, P < 0,01).

Hygienic and grooming behaviors in African and European honeybees—New damage categories in Varroa destructor

PubMed Central

Fombong, Ayuka T.; Yusuf, Abdullahi A.; Pirk, Christian W. W.; Stuhl, Charles

2017-01-01

Varroa destructor is an ectoparasitic pest of honeybees, and a threat to the survival of the apiculture industry. Several studies have shown that unlike European honeybees, African honeybee populations appear to be minimally affected when attacked by this mite. However, little is known about the underlying drivers contributing to survival of African honeybee populations against the mite. We hypothesized that resistant behavioral defenses are responsible for the survival of African honeybees against the ectoparasite. We tested this hypothesis by comparing grooming and hygienic behaviors in the African savannah honeybee Apis mellifera scutellata in Kenya and A. mellifera hybrids of European origin in Florida, USA against the mite. Grooming behavior was assessed by determining adult mite infestation levels, daily mite fall per colony and percentage mite damage (as an indicator of adult grooming rate), while hygienic behavior was assessed by determining the brood removal rate after freeze killing a section of the brood. Our results identified two additional undescribed damaged mite categories along with the six previously known damage categories associated with the grooming behavior of both honeybee subspecies. Adult mite infestation level was approximately three-fold higher in A. mellifera hybrids of European origin than in A. m. scutellata, however, brood removal rate, adult grooming rate and daily natural mite fall were similar in both honeybee subspecies. Unlike A. mellifera hybrids of European origin, adult grooming rate and brood removal rate did not correlate with mite infestation levels on adult worker honeybee of A. m. scutellata though they were more aggressive towards the mites than their European counterparts. Our results provide valuable insights into the tolerance mechanisms that contribute to the survival of A. m. scutellata against the mite. PMID:28622341

Assessing the efficacy of a novel temperature and humidity control machine to minimize house dust mite allergen exposure and clinical symptoms in allergic rhinitis children sensitized to dust mites: a pilot study.

PubMed

Manuyakorn, Wiparat; Padungpak, Savitree; Luecha, Orawin; Kamchaisatian, Wasu; Sasisakulporn, Cherapat; Vilaiyuk, Soamarat; Monyakul, Veerapol; Benjaponpitak, Suwat

2015-06-01

House dust mite avoidance is advised in dust mite sensitized patients to decrease the risk to develop allergic symptoms. Maintaining a relative humidity (RH) of less than 50% in households is recommended to prevent dust mite proliferation. To investigate the efficacy of a novel temperature and humidity machine to control the level of dust mite allergens and total nasal symptom score (TNSS) in dust mite sensitized allergic rhinitis children. Children (8-15 years) with dust mite sensitized persistent allergic rhinitis (AR) were enrolled. The temperature and humidity control machine was installed in the bedroom where the enrolled children stayed for 6 months. TNSS was assessed before and every month after machine set up and the level of dust mite allergen (Der p 1 and Der f 1) from the mattress were measured before and every 2 months after machine set up using enzyme-linked immunosorbent assay (ELISA). A total of 7 children were enrolled. Noticeable reduction of Der f 1 was observed as early as 2 months after installing the machine, but proper significant differences appeared 4 months after and remained low until the end of the experiment (p <0.05). Although no correlation was observed between TNSS and the level of dust mite allergens, there was a significant reduction in TNSS at 2 and 4 months (p <0.05) and 70% of the patients were able to stop using their intranasal corticosteroids by the end of the experiment. The level of house dust mite in mattresses was significantly reduced after using the temperature and humidity control machine. This machine may be used as an effective tool to control clinical symptoms of dust mite sensitized AR children.

Disease dynamics of honeybees with Varroa destructor as parasite and virus vector.

PubMed

Kang, Yun; Blanco, Krystal; Davis, Talia; Wang, Ying; DeGrandi-Hoffman, Gloria

2016-05-01

The worldwide decline in honeybee colonies during the past 50 years has often been linked to the spread of the parasitic mite Varroa destructor and its interaction with certain honeybee viruses carried by Varroa mites. In this paper, we propose a honeybee-mite-virus model that incorporates (1) parasitic interactions between honeybees and the Varroa mites; (2) five virus transmission terms between honeybees and mites at different stages of Varroa mites: from honeybees to honeybees, from adult honeybees to the phoretic mites, from brood to the reproductive mites, from the reproductive mites to brood, and from adult honeybees to the phoretic mites; and (3) Allee effects in the honeybee population generated by its internal organization such as division of labor. We provide completed local and global analysis for the full system and its subsystems. Our analytical and numerical results allow us have a better understanding of the synergistic effects of parasitism and virus infections on honeybee population dynamics and its persistence. Interesting findings from our work include: (a) due to Allee effects experienced by the honeybee population, initial conditions are essential for the survival of the colony. (b) Low adult honeybees to brood ratios have destabilizing effects on the system which generate fluctuating dynamics that lead to a catastrophic event where both honeybees and mites suddenly become extinct. This catastrophic event could be potentially linked to Colony Collapse Disorder (CCD) of honeybee colonies. (c) Virus infections may have stabilizing effects on the system, and parasitic mites could make disease more persistent. Our model illustrates how the synergy between the parasitic mites and virus infections consequently generates rich dynamics including multiple attractors where all species can coexist or go extinct depending on initial conditions. Our findings may provide important insights on honeybee viruses and parasites and how to best control them. Copyright © 2016 Elsevier Inc. All rights reserved.

Niche Partitioning of Feather Mites within a Seabird Host, Calonectris borealis

PubMed Central

Stefan, Laura M.; Gómez-Díaz, Elena; Elguero, Eric; Proctor, Heather C.; McCoy, Karen D.; González-Solís, Jacob

2015-01-01

According to classic niche theory, species can coexist in heterogeneous environments by reducing interspecific competition via niche partitioning, e.g. trophic or spatial partitioning. However, support for the role of competition on niche partitioning remains controversial. Here, we tested for spatial and trophic partitioning in feather mites, a diverse and abundant group of arthropods. We focused on the two dominant mite species, Microspalax brevipes and Zachvatkinia ovata, inhabiting flight feathers of the Cory’s shearwater, Calonectris borealis. We performed mite counts across and within primary and tail feathers on free-living shearwaters breeding on an oceanic island (Gran Canaria, Canary Islands). We then investigated trophic relationships between the two mite species and the host using stable isotope analyses of carbon and nitrogen on mite tissues and potential host food sources. The distribution of the two mite species showed clear spatial segregation among feathers; M. brevipes showed high preference for the central wing primary feathers, whereas Z. ovata was restricted to the two outermost primaries. Morphological differences between M. brevipes and Z. ovata support an adaptive basis for the spatial segregation of the two mite species. However, the two mites overlap in some central primaries and statistical modeling showed that Z. ovata tends to outcompete M. brevipes. Isotopic analyses indicated similar isotopic values for the two mite species and a strong correlation in carbon signatures between mites inhabiting the same individual host suggesting that diet is mainly based on shared host-associated resources. Among the four candidate tissues examined (blood, feather remains, skin remains and preen gland oil), we conclude that the diet is most likely dominated by preen gland oil, while the contribution of exogenous material to mite diets is less marked. Our results indicate that ongoing competition for space and resources plays a central role in structuring feather mite communities. They also illustrate that symbiotic infracommunities are excellent model systems to study trophic ecology, and can improve our understanding of mechanisms of niche differentiation and species coexistence. PMID:26650672

Pathogenic differences of the entomopathogenic fungus Isaria cateniannulata to the spider mite Tetranychus urticae (Trombidiformes: Tetranychidae) and its predator Euseius nicholsi (Mesostigmata: Phytoseiidae).

PubMed

Zhang, Xiao-Na; Guo, Jian-Jun; Zou, Xiao; Jin, Dao-Chao

2018-05-01

Isaria cateniannulata and Euseius nicholsi are two important biological control agents currently being used in many areas of China to control a variety of pests. In order to determine the possibility of a concomitant application with the two agents in a biocontrol program involving the two-spotted spider mite, Tetranychus urticae, we quantified the pathogenicity of a strain of I. cateniannulata (08XS-1) against females of both T. urticae and E. nicholsi. We observed the infection process using scanning electron microscopy and fluorescence microscopy to distinguish differences in fungal performance. The female mites were infected by I. cateniannulata at 2 × 10 7 conidia/ml. The mortality of T. urticae was 100% when treated with submerged conidia and 92% when treated with aerial conidia (spray), and that of E. nicholsi was 4.2 and 6.7%, correspondingly. Following infection with aerial or submerged conidia, mated E. nicholsi females displayed no significant differences between treatments and control, indicating the fungus had no obvious effect on their vitality and fertility. This demonstrates that I. cateniannulata is safe to E. nicholsi when used to control T. urticae. The two types of propagules of I. cateniannulata are readily produced by common culture, and the submerged conidia, because of their substantially higher mortality, are preferable to the aerial conidia. Our results indicate that I. cateniannulata and E. nicholsi are viable candidates to be concomitantly applied in the biocontrol programs of T. urticae.

Variability in Population Density of House Dust Mites of Bitlis and Muş, Turkey.

PubMed

Aykut, M; Erman, O K; Doğan, S

2016-05-01

This study was conducted to investigate the relationship between the number of house dust mites/g dust and different physical and environmental variables. A total of 1,040 house dust samples were collected from houses in Bitlis and Muş Provinces, Turkey, between May 2010 and February 2012. Overall, 751 (72.2%) of dust samples were mite positive. The number of mites/g dust varied between 20 and 1,840 in mite-positive houses. A significant correlation was detected between mean number of mites and altitude of houses, frequency of monthly vacuum cleaning, number of individuals in the household, and relative humidity. No association was found between the number of mites and temperature, type of heating, existence of allergic diseases, age and structure of houses. A maximum number of mites were detected in summer and a minimum number was detected in autumn. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Candidate predators for biological control of the poultry red mite Dermanyssus gallinae.

PubMed

Lesna, Izabela; Wolfs, Peter; Faraji, Farid; Roy, Lise; Komdeur, Jan; Sabelis, Maurice W

2009-06-01

The poultry red mite, Dermanyssus gallinae, is currently a significant pest in the poultry industry in Europe. Biological control by the introduction of predatory mites is one of the various options for controlling poultry red mites. Here, we present the first results of an attempt to identify potential predators by surveying the mite fauna of European starling (Sturnus vulgaris) nests, by assessing their ability to feed on poultry red mites and by testing for their inability to extract blood from bird hosts, i.e., newly hatched, young starlings and chickens. Two genuine predators of poultry red mites are identified: Hypoaspis aculeifer and Androlaelaps casalis. A review of the literature shows that some authors suspected the latter species to parasitize on the blood of birds and mammals, but they did not provide experimental evidence for these feeding habits and/or overlooked published evidence showing the reverse. We advocate careful analysis of the trophic structure of arthropods inhabiting bird nests as a basis for identifying candidate predators for control of poultry red mites.

Plant-eriophyoid mite interactions: cellular biochemistry and metabolic responses induced in mite-injured plants. Part I.

PubMed

Petanović, Radmila; Kielkiewicz, Malgorzata

2010-07-01

This review is a comprehensive study of recent advances related to cytological, biochemical and physiological changes induced in plants in response to eriophyoid mite attack. It has been shown that responses of host plants to eriophyoids are variable. Most of the variability is due to individual eriophyoid mite-plant interactions. Usually, the direction and intensity of changes in eriophyoid-infested plant organs depend on mite genotype, density, or the feeding period, and are strongly differentiated relative to host plant species, cultivar, age and location. Although the mechanisms of changes elicited by eriophyoid mites within plants are not fully understood, in many cases the qualitative and quantitative biochemical status of mite-infested plants are known to affect the performance of consecutive herbivorous arthropods. In future, elucidation of the pathways from eriophyoid mite damage to plant gene activation will be necessary to clarify plant responses and to explain variation in plant tissue damage at the feeding and adjacent sites.

Species diversity of ectoparasitic chigger mites (Acari: Prostigmata) on small mammals in Yunnan Province, China.

PubMed

Peng, Pei-Ying; Guo, Xian-Guo; Ren, Tian-Guang; Song, Wen-Yu; Dong, Wen-Ge; Fan, Rong

2016-09-01

Chigger mites are a large group of arthropods and the larvae of mites are ectoparasites. Some species of ectoparasitic mites (larvae) can be the transmitting vectors of tsutsugamushi disease (scrub typhus). Yunnan Province is located in the southwest of China with complicated topographic landform and high biodiversity, where there are five zoogeographical subregions. Rodents and some other small mammals were trapped and examined for ectoparasitic chigger mites in 29 investigation sites in Yunnan during 2001-2013. From 13,760 individuals and 76 species of small mammal hosts, we collected 274 species of mites, which were identified as comprising 26 genera in two families. The species diversity of chigger mites (274 species) in the present study were not only much higher than that from other provinces of China but also largely exceeded that recorded from other regions and countries in the world. Of the five zoogeographical subregions, both the species diversity and Shannon-Weiner's diversity of mites were the highest in subregion II (southern subregion of Hengduan Mountains) with middle altitudes and middle latitude. Both the species diversity of mites and Shannon-Wiener diversity index showed a parabolic tendency from the low altitude (<500 m) to the high altitude (>3500 m) along the vertical gradients with the peak occurring in the middle-altitude regions (2000-2500 m). Of four dominant hosts, the species richness of mites was highest on Eothenomys miletus (S = 165) and Shannon-Wiener diversity index was highest on Rattus norvegicus (H = 3.13). Along latitude gradients, species richness of chigger mites increased first and then decreased, peaking at 25° to 26° N with 193 mite species. The geographical location, complex topography, and landscape with diverse small mammal hosts in Yunnan Province have contributed to the extremely high species diversity of mites in the province. The large sampling size of small mammal hosts in a wide geographical scope within a long time span also made it possible to have collected so many species of chigger mites.

Fusarium semitectum, a potential mycopathogen against thrips and mites in chilli, Capsicum annuum.

PubMed

Mikunthan, G; Manjunatha, M

2006-01-01

In India, chilli (Capsicum annuum L.) suffers with a characteristic leaf curl symptoms due to the attack of mite, Polyphagotarsonemus latus (Banks) (Acari: Tarsonemidae) and thrips, Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) or both. Experiments were conducted in the fields of College of Agriculture, Shimoga, India during kharif (September 2003 to January 2004) and summer (March-June) 2004. After proving its pathogenicity, the potential of the mycopathogen, Fusarium semitectum was evaluated under field conditions using the popular chilli variety "Byadagi". Different combinations of Fusarium semitectum formulations with monocrotophos (0.025% and 0.05%) were tested. Oil-emulsion and dust-water formulations (DWF) at 1x 10(8) spore/ml, DWF with monocrotophos and 5% Neem Seed Kernal Extract (NSKE) were evaluated. Population of S. dorsalis, P. latus, predatory mite Amblyseius ovalis and damage index were estimated. Populations of thrips, mite and the predatory mite were estimated at 15 days interval after 30 days of transplanting. Damage index was assessed using a visual rating method. Plant height, fruit length and dry chilli yield of each treatment were also taken. Among the treatments, oil-emulsion formulation and dust water formulation of F. semitectum in combination with monocrotophos (0.05%) reduced the population of thrips significantly over other treatments. Dust water formulation was achieved a significant decline of thrips population in chilli plants after 60 days of transplanting. This reduction of thrips population could be achieved due to the effect of second spraying, which was given at 50 days after transplanting. Chilli plant height and fruit length did not vary significantly among the treatment in both seasons. The highest dry chilli yield of 512 and 1058 kg/ha was recorded in dust water formulation in combination with monocrotophos (0.05%) followed by oil formulation (432 kg/ha and 763 kg/ha) in Kharif and summer seasons, respectively. Fusarium formulation sprayed plots were recorded low damage index than NSKE, water sprayed plots including control. Oil-emulsion formulation treated plot adjusted the highest benefit cost ratio of 6.07:1. Oil emulsion formulation (refined sunflower oil-Safola) was next best to the dust water formulation of F. semitectum. and monocrotophos combination and more-over equal to the monocrotophos 0.05% alone in suppressing the thrips and mite population. These results revealed that dust water formulation in combination with monocrotophos (0.05%) was able to suppress the population of thrips and mites and thus was able to give highest dry chilli yield. Oil emulsion formulation of F. semitectum can also be used as the next best choice in an environment friendly integrated chilli pest management programme.

Ectoparasitic chigger mites on large oriental vole (Eothenomys miletus) across southwest, China.

PubMed

Peng, Pei-Ying; Guo, Xian-Guo; Song, Wen-Yu; Hou, Peng; Zou, Yun-Ji; Fan, Rong

2016-02-01

An investigation of chigger mites on the large oriental vole, Eothenomys miletus (Rodentia: Cricetidae), was conducted between 2001 and 2013 at 39 localities across southwest China, and 2463 individuals of the vole hosts were captured and examined, which is a big host sample size. From the body surface of E. miletus, 49,850 individuals of chigger mites were collected, and they were identified as comprising 175 species, 13 genera, and 3 subfamilies in 2 families (Trombiculidae and Leeuwenhoekiidae). The 175 species of chigger mites from such a single rodent species (E. miletus) within a certain region (southwest China) extremely exceeded all the species of chigger mites previously recorded from multiple species of hosts in a wide region or a whole country in some other countries, and this suggests that E. miletus has a great potential to harbor abundant species of chigger mites on its body surface. Of 175 mite species, Leptotrombidium scutellare was the most dominant species, which has been proved as one of the main vectors of scrub typhus and the potential vector of haemorrhagic fever with renal syndrome (HFRS) in China. The patchiness index (m*/m) was used to measure the spatial patterns of the dominant chigger mite species, and all the three dominant mite species (L. scutellare, Leptotrombidium sinicum, and Helenicula simena) showed aggregated distributions among the different host individuals. The coefficient of association (V) was adopted to measure the interspecies interaction between the dominant mite species and a slightly positive association existed between L. scutellare and L. sinicum (V = 0.28, P < 0.01), which implies that these two mite species can co-exist on the same species of the host, E. miletus. The tendency curve of species abundance showed that the number of chigger mite species gradually decreased with the increase of mite individuals, and this revealed that most chigger mite species were rare with very few individuals, but few dominant species had abundant individuals. The species-sample relationship indicated that the number of chigger mite species increased with the increase of the host samples. The results suggest that a big host sample size over a wide realm of geographical regions is needed in the field investigation in order to obtain a true picture of species diversity and species composition.

Plant structural changes due to herbivory: Do changes in Aceria-infested coconut fruits allow predatory mites to move under the perianth?

PubMed Central

Aratchige, Nayanie S.; Lesna, Izabela

2007-01-01

Being minute in size, eriophyoid mites can reach places that are small enough to be inaccessible to their predators. The coconut mite, Aceria guerreronis, is a typical example; it finds partial refuge under the perianth of the coconut fruit. However, some predators can move under the perianth of the coconut fruits and attack the coconut mite. In Sri Lanka, the phytoseiid mite Neoseiulus baraki, is the most common predatory mite found in association with the coconut mite. The cross-diameter of this predatory mite is c. 3 times larger than that of the coconut mite. Nevertheless, taking this predator’s flat body and elongated idiosoma into account, it is—relative to many other phytoseiid mites—better able to reach the narrow space under the perianth of infested coconut fruits. On uninfested coconut fruits, however, they are hardly ever observed under the perianth. Prompted by earlier work on the accessibility of tulip bulbs to another eriophyoid mite and its predators, we hypothesized that the structure of the coconut fruit perianth is changed in response to damage by eriophyoid mites and as a result predatory mites are better able to enter under the perianth of infested coconut fruits. This was tested in an experiment where we measured the gap between the rim of the perianth and the coconut fruit surface in three cultivars (‘Sri Lanka Tall’, ‘Sri Lanka Dwarf Green’ and ‘Sri Lanka Dwarf Green × Sri Lanka Tall’ hybrid) that are cultivated extensively in Sri Lanka. It was found that the perianth-fruit gap in uninfested coconut fruits was significantly different between cultivars: the cultivar ‘Sri Lanka Dwarf Green’ with its smaller and more elongated coconut fruits had a larger perianth-fruit gap. In the uninfested coconut fruits this gap was large enough for the coconut mite to creep under the perianth, yet too small for its predator N. baraki. However, when the coconut fruits were infested by coconut mites, the perianth-rim-fruit gap was not different among cultivars and had increased to such an extent that the space under the perianth became accessible to the predatory mites. PMID:17899401

[Role of the poultry red mite (Dermanyssus gallinae) in the transmission of avian influenza A virus].

PubMed

Sommer, D; Heffels-Redmann, U; Köhler, K; Lierz, M; Kaleta, E F

2016-01-01

The aim of this study was to investigate the role of the poultry red mite (Dermanyssus [D.] gallinae) in the horizontal transmission of avian influenza A virus (AIV) to chickens. This mite is the most common ectoparasite in poultry worldwide, and may play a role in the spread of infectious agents including AIV. Currently, the control of mites is difficult due to frequently developed resistance to many acaricides, their nocturnality and their ability to survive hidden without feeding for months. D. gallinae were collected in a commercial layer farm and housed in self-made fibreboard boxes. SPF chickens were intravenously infected with AIV strain A/turkey/Ontario/7732/1966 (H5N9). The viraemia in chickens was monitored and at an appropriate time point about 1000 mites were allowed to suck on the AIV infected chickens. Re-isolation of the virus from blood-filled mites was tried daily for 14 days using chicken embryo fibroblast cultures and embryonated chicken eggs. Subsequently, the virus containing mites were placed into boxes that contained naïve SPF chickens to enable virus transmission from mites to chickens. Possible transmission to the chickens was examined using clinical signs, serology, gross lesions, histopathology and immunohistochemistry. Chickens developed a dose-dependent viraemia one day after infection, therefore this day was chosen for the bloodmeal of the mites. AIV was detected in mites after bloodsucking on AIV-infected chickens over a 10-day period. Naïve SPF chickens were infected during bloodsucking of AIV carrying mites. AIV isolates in mites and in chickens were undistinguishable from the original AIV inoculum by RT-PCR. D. gallinae ingested AIV during bloodmeals on AIV infected chickens and are able to transmit AIV to SPF chickens. Therefore, mites serve as mechanical vector of AIV and may play a major role in the circulation of AIV within a facility or area although the life span of infectious virus in the mite is limited. The proven transmission requires more than ever a systematic control of this ectoparasite in order to maintain poultry health and productivity. The demonstrated vector function of this mite is of great significance for poultry flocks all over the world.

[Atopic dermatitis and domestic animals].

PubMed

Song, M

2000-09-01

Several arguments are raised attributing to aeroallergens an important role in atopic dermatitis. The aeroallergens that penetrate the epidermis could be fixed by IgE on the Langerhans cells and then induce a cellular mediator reaction comparable to that of allergic contact eczema. Patch tests have been developed to evaluate the role of aeroallergens (dust mites, animal dander, etc.). Preventive anti-dust mites measures in the home of atopic patients are recommended. Eviction of domestic animals (cat, dog, etc.) or avoidance measures for animal dander in the home can produce improvement in atopic dermatitis. Oral specific immunotherapy is being validated as a treatment for this disease.

Acaricidal activity of pine essential oils and their main components against Tyrophagus putrescentiae, a stored food mite.

PubMed

Macchioni, F; Cioni, P L; Flamini, G; Morelli, I; Perrucci, S; Franceschi, A; Macchioni, G; Ceccarini, L

2002-07-31

Some essential oils obtained from the branches of four Pinus species (P. pinea L., P. halepensis Mill., P. pinaster Soil in Ait., and P. nigra Arnold) have been evaluated for their acaricidal activity by aerial diffusion against the stored food mite Tyrophagus putrescentiae (L.). All the essential oils showed a good efficacy, but P. pinea oil and its two constituents 1,8-cineole and limonene were the most effective compounds, showing 100% acaricidal activity at 8 microL; 1,8-cineole showed the same activity at 6 microL.

Influence of fruit age of the Brazilian Green Dwarf coconut on the relationship between Aceria guerreronis population density and percentage of fruit damage.

PubMed

Sousa, André Silva Guimarães; Argolo, Poliane Sá; Gondim, Manoel Guedes Correa; de Moraes, Gilberto José; Oliveira, Anibal Ramadan

2017-08-01

The coconut mite, Aceria guerreronis Keifer (Acari: Eriophyidae), is one of the main coconut pests in the American, African and parts of the Asian continents, reaching densities of several thousand mites per fruit. Diagrammatic scales have been developed to standardize the estimation of the population densities of A. guerreronis according to the estimated percentage of damage, but these have not taken into account the possible effect of fruit age, although previous studies have already reported the variation in mite numbers with fruit age. The objective of this study was to re-construct the relation between damage and mite density at different fruit ages collected in an urban coconut plantation containing the green dwarf variety ranging from the beginning to nearly the end of the infestation, as regularly seen under field conditions in northeast Brazil, in order to improve future estimates with diagrammatic scales. The percentage of damage was estimated with two diagrammatic scales on a total of 470 fruits from 1 to 5 months old, from a field at Ilhéus, Bahia, Brazil, determining the respective number of mites on each fruit. The results suggested that in estimates with diagrammatic scales: (1) fruit age has a major effect on the estimation of A. guerreronis densities, (2) fruits of different ages should be analyzed separately, and (3) regular evaluation of infestation levels should be done preferably on fruits of about 3-4 months old, which show the highest densities.

[Animal mite-induced epizoonoses and their significance in dermatology].

PubMed

Beck, W

1996-10-01

Different mite species may infest humans temporarily; such arthropods should be considered a possible cause of pruritic skin reactions of unclear origin. Pseudo-scabies is a common problem. This self-limiting dermatosis may often be misdiagnosed. Several mite species including Sarcoptes scabiei var. canis, Sarcoptes scabiei var. bovis, Notoedres cati, Cheyletiella yasguri, Cheyletiella blakei, Dermanyssus gallinae and Ophionyssus natricis may infest human skin, causing symptoms. Other less common animal mites, Neotrombicula autumnalis and foodstuff mites are also discussed.

Tetranychus urticae mites do not mount an induced immune response against bacteria

PubMed Central

Santos-Matos, Gonçalo; Wybouw, Nicky; Martins, Nelson E.; Zélé, Flore; Riga, Maria; Leitão, Alexandre B.; Vontas, John; Grbić, Miodrag; Van Leeuwen, Thomas; Magalhães, Sara

2017-01-01

The genome of the spider mite Tetranychus urticae, a herbivore, is missing important elements of the canonical Drosophila immune pathways necessary to fight bacterial infections. However, it is not known whether spider mites can mount an immune response and survive bacterial infection. In other chelicerates, bacterial infection elicits a response mediated by immune effectors leading to the survival of infected organisms. In T. urticae, infection by either Escherichia coli or Bacillus megaterium did not elicit a response as assessed through genome-wide transcriptomic analysis. In line with this, spider mites died within days even upon injection with low doses of bacteria that are non-pathogenic to Drosophila. Moreover, bacterial populations grew exponentially inside the infected spider mites. By contrast, Sancassania berlesei, a litter-dwelling mite, controlled bacterial proliferation and resisted infections with both Gram-negative and Gram-positive bacteria lethal to T. urticae. This differential mortality between mite species was absent when mites were infected with heat-killed bacteria. Also, we found that spider mites harbour in their gut 1000-fold less bacteria than S. berlesei. We show that T. urticae has lost the capacity to mount an induced immune response against bacteria, in contrast to other mites and chelicerates but similarly to the phloem feeding aphid Acyrthosiphon pisum. Hence, our results reinforce the putative evolutionary link between ecological conditions regarding exposure to bacteria and the architecture of the immune response. PMID:28592670

Bacterial communities associated with the ectoparasitic mites Varroa destructor and Tropilaelaps mercedesae of the honey bee (Apis mellifera).

PubMed

Pakwan, Chonthicha; Kaltenpoth, Martin; Weiss, Benjamin; Chantawannakul, Panuwan; Jun, Guo; Disayathanoowat, Terd

2017-12-01

Varroa and Tropilaelaps mites have been reported as serious ectoparasites of the honey bee (Apis mellifera). In this study, bacterial communities associated with Varroa destructor and Tropilaelaps mercedesae from northern Thailand were determined, using both culture-dependent and culture-independent approaches. Adult female mites were collected from apiaries in Chiang Mai and Lampang provinces. Culturable bacteria were isolated from individual mites. On average, we observed approximately 1340 and 1140 CFU/mite in Varroa and Tropilaelaps, respectively. All isolates were assigned to the genus Enterococcus. Six samples of genomic DNA from 30-50 mites were extracted and subjected to pyrosequencing of bacterial 16S rRNA amplicons. The resulting 81 717 sequences obtained from Varroa were grouped into 429 operational taxonomic units. The most abundant bacteria in Varroa mites belonged to the family Enterobacteriaceae, especially the genera Arsenophonus, Enterobacter and Proteus. For Tropilaelaps mites, 84 075 sequences were obtained and clustered into 166 operational taxonomic units, within which the family Enterococcaceae (particularly the genus Enterococcus) was predominant. Localization of bacteria in the mites using fluorescence in situ hybridization with two universal bacterial probes revealed that these bacteria were in the cecum of the mites. Taxon-specific Enterobacteriaceae and Arsenophonus probes also confirmed their localization in the cecum of Varroa. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Practical sampling plans for Varroa destructor (Acari: Varroidae) in Apis mellifera (Hymenoptera: Apidae) colonies and apiaries.

PubMed

Lee, K V; Moon, R D; Burkness, E C; Hutchison, W D; Spivak, M

2010-08-01

The parasitic mite Varroa destructor Anderson & Trueman (Acari: Varroidae) is arguably the most detrimental pest of the European-derived honey bee, Apis mellifera L. Unfortunately, beekeepers lack a standardized sampling plan to make informed treatment decisions. Based on data from 31 commercial apiaries, we developed sampling plans for use by beekeepers and researchers to estimate the density of mites in individual colonies or whole apiaries. Beekeepers can estimate a colony's mite density with chosen level of precision by dislodging mites from approximately to 300 adult bees taken from one brood box frame in the colony, and they can extrapolate to mite density on a colony's adults and pupae combined by doubling the number of mites on adults. For sampling whole apiaries, beekeepers can repeat the process in each of n = 8 colonies, regardless of apiary size. Researchers desiring greater precision can estimate mite density in an individual colony by examining three, 300-bee sample units. Extrapolation to density on adults and pupae may require independent estimates of numbers of adults, of pupae, and of their respective mite densities. Researchers can estimate apiary-level mite density by taking one 300-bee sample unit per colony, but should do so from a variable number of colonies, depending on apiary size. These practical sampling plans will allow beekeepers and researchers to quantify mite infestation levels and enhance understanding and management of V. destructor.

Comparison between Siriraj mite allergen vaccine and standardized commercial mite vaccine by skin prick testing in normal Thai adults.

PubMed

Visitsunthorn, Nualanong; Pacharn, Punchama; Jirapongsananuruk, Orathai; Weeravejsukit, Sirirat; Sripramong, Chaweewan; Sookrung, Nitat; Bunnag, Chaweewan

2010-03-01

House dust mite is a major cause of allergic asthma and rhinitis in Thai population. Skin prick test (SPT) is a useful tool for the diagnosis of the IgE-mediated reactions. The imported commercial mite vaccine for SPT is available but it is relatively expensive. Aim of this study is to compare Siriraj Mite Allergen Vaccine (SMAV) with standardized commercial mite allergen vaccine by skin prick testing in normal Thai adults. A double blind, self-controlled study between the SMAV and standardized commercial mite allergen vaccine was performed by SPT in 17 normal Thai adult males and non-pregnant or non-lactating females aged 18-60 years. The study showed that 35.29 % of non atopic adults had positive SPT reaction to Dp and Df of both SMAV and standardized commercial mite allergen vaccine. Mean wheal and flare diameters from SPT of Dp and Df of SMAV showed strong correlation with standardized commercial mite allergen vaccine (r= 0.768 and 0.897 in Dp and Df respectively, p <0.001). The intraclass correlation was also excellent (0.893 and 0.775 in Dp and Df respectively). There was no significant difference in wheal and flare diameter between SMAV and standardized commercial mite allergen vaccine. No systemic or large local reaction was found in any of the study cases.

Tetranychus urticae mites do not mount an induced immune response against bacteria.

PubMed

Santos-Matos, Gonçalo; Wybouw, Nicky; Martins, Nelson E; Zélé, Flore; Riga, Maria; Leitão, Alexandre B; Vontas, John; Grbić, Miodrag; Van Leeuwen, Thomas; Magalhães, Sara; Sucena, Élio

2017-06-14

The genome of the spider mite Tetranychus urticae , a herbivore, is missing important elements of the canonical Drosophila immune pathways necessary to fight bacterial infections. However, it is not known whether spider mites can mount an immune response and survive bacterial infection. In other chelicerates, bacterial infection elicits a response mediated by immune effectors leading to the survival of infected organisms. In T. urticae , infection by either Escherichia coli or Bacillus megaterium did not elicit a response as assessed through genome-wide transcriptomic analysis. In line with this, spider mites died within days even upon injection with low doses of bacteria that are non-pathogenic to Drosophila Moreover, bacterial populations grew exponentially inside the infected spider mites. By contrast, Sancassania berlesei , a litter-dwelling mite, controlled bacterial proliferation and resisted infections with both Gram-negative and Gram-positive bacteria lethal to T. urticae This differential mortality between mite species was absent when mites were infected with heat-killed bacteria. Also, we found that spider mites harbour in their gut 1000-fold less bacteria than S. berlesei We show that T. urticae has lost the capacity to mount an induced immune response against bacteria, in contrast to other mites and chelicerates but similarly to the phloem feeding aphid Acyrthosiphon pisum Hence, our results reinforce the putative evolutionary link between ecological conditions regarding exposure to bacteria and the architecture of the immune response. © 2017 The Authors.

LD50 and repellent effects of essential oils from Argentinian wild plant species on Varroa destructor.

PubMed

Ruffinengo, Sergio; Eguaras, Martin; Floris, Ignazio; Faverin, Claudia; Bailac, Pedro; Ponzi, Marta

2005-06-01

The repellent and acaricidal effects of some essential oils from the most typical wild plant species of northern Patagonia, Argentina, on Varroa destructor Anderson & Trueman were evaluated using a complete exposure test. Honey bees, Apis mellifera L., and mites (five specimens of each per dish) were introduced in petri dishes having different oil concentrations (from 0.1 to 25 micro per cage). Survival of bees and mites was registered after 24, 48, and 72 h. An attraction/repellence test was performed using a wax tube impregnated with essential oil and another tube containing wax only. The lowest LD50 values for mites were registered for Acantholippia seriphioides (A. Gray) Mold. (1.27 microl per cage) and Schinus molle L. (2.65 microl per cage) after 24 h, and for Wedelia glauca (Ortega) O. Hoffm. ex Hicken (0.59 microl per cage) and A. seriphioides (1.09 microl per cage) after 72 h of treatment. The oil with the highest selectivity ratio (A. mellifera LD50/V. destructor LD50) was the one extracted from S. molle (>16). Oils of Lippia junelliana (Mold.) Troncoso, Minthostachys mollis (HBK) Grieseb., and Lippia turbinata Grieseb. mixed with wax had repellent properties. None of the oils tested had attractive effects on Varroa mites.

Sensitization to allergens of house-dust mite in adults with atopic dermatitis in a cold temperature region.

PubMed

Holm, L; van Hage-Hamsten, M; Ohman, S; Scheynius, A

1999-07-01

An IgE-mediated contact reaction to airborne allergens has been suggested as one important pathogenetic mechanism in atopic dermatitis (AD). The house-dust mite (HDM) might be a common allergen involved. In Scandinavia, sensitization to HDM has been rare, probably because of the cold, dry climate. However, recent studies indicate high levels of domestic mites and HDM allergen in 15-20% of homes in central and northern Sweden. To evaluate the importance of the HDM in patients with AD in the Stockholm region, we screened 81 adult Stockholm residents with AD, for the prevalence and degree of sensitization to the HDM, according to specific IgE (RAST), skin prick test (SPT), and atopy patch test (APT). We also assessed the HDM exposure in their homes and correlated the results with clinical history, severity of the dermatitis, and type of residence during childhood and today. The sensitization rate to HDM was high (56% according to RAST, 24% according to SPT, and 47% according to APT), and 20% of the patients were exposed to HDM allergens in their beds. Mite exposure seemed to aggravate the dermatitis in highly sensitized patients. The results indicate that we have to take the HDM into account when discussing aggravating factors in adult patients with AD in the Stockholm region.

Molecular identification of house dust mites and storage mites.

PubMed

Wong, Shew Fung; Chong, Ai Ling; Mak, Joon Wah; Tan, Jessie; Ling, Suk Jiun; Ho, Tze Ming

2011-10-01

Mites are known causes of allergic diseases. Currently, identification of mites based on morphology is difficult if only one mite is isolated from a (dust) sample, or when only one gender is found, or when the specimen is not intact especially with the loss of the legs. The purpose of this study was to use polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) of the ITS2 gene, to complement the morphological data for the identification of mites to the species level. For this, six species were cultured: Dermatophagoides pteronyssinus, D. farinae, Blomia tropicalis, Tyrophagus putrescentiae, Aleuroglyphus ovatus and Glycycometus malaysiensis. Genomic DNA of the mites was extracted, quantified, amplified and digested individually with restriction enzymes. Hinf I and Ple I differentiated the restriction patterns of D. pteronyssinus and D. farinae. Bfa I and Alu I enzymes differentiated B. tropicalis and G. malaysiensis. Ple I enzyme was useful for the differentiation between T. putrescentiae and A. ovatus. Bfa I was useful for the differentiation of G. malaysiensis from the rest of the species. In conclusion, different species of mites can be differentiated using PCR-RFLP of ITS2 region. With the established PCR-RFLP method in this study, identification of these mites to the species level is possible even if complete and intact adult specimens of both sexes are not available. As no study to date has reported PCR-RFLP method for the identification of domestic mites, the established method should be validated for the identification of other species of mites that were not included in this study.

Examining the role of foraging and malvolio in host-finding behavior in the honey bee parasite, Varroa destructor (Anderson & Trueman).

PubMed

Cabrera, Ana R; Shirk, Paul D; Teal, Peter E A; Grozinger, Christina M; Evans, Jay D

2014-02-01

When a female varroa mite, Varroa destructor (Anderson & Trueman), invades a honey bee brood cell, the physiology rapidly changes from feeding phoretic to reproductive. Changes in foraging and malvolio transcript levels in the brain have been associated with modulated intra-specific food searching behaviors in insects and other invertebrates. Transcription profiles for both genes were examined during and immediately following brood cell invasion to assess their role as potential control elements. Vdfor and Vdmvl transcripts were found in all organs of varroa mites with the highest Vdfor transcript levels in ovary-lyrate organs and the highest Vdmvl in Malpighian tubules. Changes in transcript levels of Vdfor and Vdmvl in synganglia were not associated with the cell invasion process, remaining comparable between early reproductive mites (collected from the pre-capping brood cells) and phoretic mites. However, Vdfor and Vdmvl transcript levels were lowered by 37 and 53%, respectively, in synganglia from reproductive mites compared to early reproductive mites, but not significantly different to levels in synganglia from phoretic mites. On the other hand, in whole body preparations the Vdfor and Vdmvl had significantly higher levels of transcript in reproductive mites compared to phoretic and early reproductive, mainly due to the presence of both transcripts accumulating in the eggs carried by the ovipositing mite. Varroa mites are a critical component for honey bee population decline and finding varroa mite genes associated with brood cell invasion, reproduction, ion balance and other physiological processes will facilitate development of novel control avenues for this honey bee parasite. © 2013 Wiley Periodicals, Inc.

Comparison of Preferred Bite Sites between Mites and Ticks on Humans in Korea

PubMed Central

Jang, Mi-Sun; Kim, Choon-Mee; Kim, Dong-Min; Yoon, Na Ra; Han, Mi Ah; Kim, Hyun-Kuk; Oh, Won Sup; Yoon, Hee-Jung; Wie, Seong-Heon; Hur, Jian

2016-01-01

Identification of mite and tick bite sites provides important clinical information. The predominant mite species in Korea associated with scrub typhus are Leptotrombidium pallidum and Leptotrombidium scutellare. The most abundant tick species is Haemaphysalis longicornis. To date, there has been no comparative study on preferred bite sites between mites and ticks in humans. This study included a review of medical records and a field study. For mite bite sites, eschars were checked on 506 patients with scrub typhus, confirmed by indirect immunofluorescence assay or nested polymerase chain reaction on the 56-kDa type-specific antigen gene of Orientia tsutsugamushi. Tick bite sites were identified and marked on a diagram for 91 patients who experienced tick bites within the previous year through a field epidemiological investigation. The mite and tick bite sites in Koreans were compared. The most frequently observed mite bite sites were the anterior chest, including the axillae (29.1%) and the abdominal region, including the inguinal area (26.1%). Tick bite sites were most frequent on the lower extremities (33.0%), followed by the abdominal region, including the inguinal area (26.4%), and upper extremities (26.4%). The distribution was significantly different between mite and tick bite sites (P < 0.001). There was a statistically significant difference in the mite bite (P = 0.001), but not tick bite sites (P = 0.985), between men and women. This is the first report on the differences between tick and mite bite sites, and may help clinicians reach a rapid diagnosis of mite- or tick-borne infection. PMID:27645781

Mites and fungi in heavily infested stores in the Czech Republic.

PubMed

Hubert, J; Stejskal, V; Munzbergová, Z; Kubátová, A; Vánová, M; Zd'árková, E

2004-12-01

Toxigenic and allergen-producing fungi represent a serious hazard to human food and animal feed safety. Ninety-four fungal species were isolated from mite-infested samples of seeds taken from Czech seed stores. Fungi were isolated from the surface of four kinds of seeds (wheat, poppy, lettuce, and mustard) and from the gut and external surface of five species of mites (i.e., Acarus siro L., 1758, Caloglyphus rhizoglyphoides (Zachvatkin, 1973), Lepidoglyphus destructor (Schrank, 1781), Tyrophagus putrescentnae (Schrank, 1781) and Cheyletus malaccensis Oudemans 1903) separately. Multivariate analysis of fungi complex composition showed that the frequency of fungal was species significantly influenced by the kind of seed. Fungal frequencies differed between mites gut and exoskeleton surface and between the surfaces of mites and seeds. Three groups of fungal species were recognized: 1) mite surface-associated fungi: Penicillium brevicompactum, Alternaria alternata, and Aspergillus versicolor; 2) mite surface- and seed-associated fungi: Aspergillus niger, Penicillium crustosum, Penicillium aurantiogriseum, Penicillium chrysogenum, and Aspergillus flavus; and 3) seed-associated fungi: Cladosporium herbarum, Mucor dimorphosporus f. dimorphosporus, Botrytis cinerea, Penicillium griseofulvum, and Eurotium repens. Mite-carried species of microfungi are known to produce serious mycotoxins (e.g., aflatoxin B1, cyclopiazonic acid, sterigmatocystin, ochratoxin A, and nephrotoxic glycopeptides) as well as allergen producers (e.g., A. alternata and P. brevicompactum). Storage mites may play an important role in the spread of some medically hazardous micromycetes. In addition, these mite-fungi associations may heighten the risk of occurrence of mycotoxins in food and feed stuffs and cause mixed contamination by fungal and mite allergens.

Allergen sensitivity (mites, insects, and pets) in a Puerto Rican population.

PubMed

Nazario, Sylvette; Zaragoza, Rafael; Velázquez, Vylma; Ramos-Valencia, Gilberto; Acantilado, Carmen; Rodríguez, Ray; Rivera, Angel M; Alvarez, María M; López-Almodóvar, Carlos; López-Malpica, Fernando

2012-03-01

The people of Puerto Rico have one of the highest asthma prevalence and morbidity rates in the U.S.A. Limited information is available on the most common allergy sensitivities among island residents. The aims of the study were to determine the most common inhalant allergen sensitivities among a convenience sample in Puerto Rico and determine as well their relationship to an asthma or a rhinitis diagnosis. In August of 2008, we evaluated a cohort of subjects visiting ambulatory clinics offering health screening; the clinics were located in two of the island's biggest cities: Guaynabo in the north and Ponce in the south. Subjects over three years of age (or their parents) visiting the clinics answered a survey on asthma and rhinitis and were skin tested for reactivity to common aeroallergens. The survey included 395 subjects with a mean age of 29 years. Thirty-six percent reported a history of asthma, of whom 83% (30% of the total participants) reported still having asthma, and 76% reported having rhinitis. Sixty-five percent of the subjects were sensitive to at least one antigen. Subjects sensitive to mites were 53% more likely to have suffered from asthma than were non-mite-sensitized subjects (OR = 1.53, p < 0.05) sensitivity to mosquitoes (OR = 2.25, p < 0.02), mites (OR = 2.53, p < 0.00001), feathers (OR = 2.72, p < 0.03), dogs (OR = 3.02, p < 0.01), or cats (OR = 3.42, p < 0.001) increased an individual's likelihood of suffering from rhinitis. The most common sensitivities identified were to mites and insects. Mite sensitivity was associated with rhinitis and asthma. Sensitivity to animal dander as well as to mosquitoes was associated to with rhinitis. Further studies are warranted to explore the relevance of allergen sensitivity in terms of asthma and rhinitis prevalence and morbidity among residents of Puerto Rico.

The responses of cucumber plants subjected to different salinity or fertilizer concentrations and reproductive success of Tetranychus urticae mites on these plants.

PubMed

Khodayari, Samira; Abedini, Fatemeh; Renault, David

2018-05-01

The plant stress hypothesis posits that a herbivore's reproductive success increases when it feeds on stressed plants, while the plant vigor hypothesis predicts that a herbivore preferentially feeds on more vigorous plants. We examined these opposing hypotheses by growing spider mites (Tetranychus urticae) on the leaves of stressed and healthy (vigorous) cucumber plants. Host plants were grown under controlled conditions at low, moderate, and high concentrations of NaCl (to induce salinity stress), at low, moderate, and high fertilizer concentrations (to support growth), and without these additions (control). The effects of these treatments were evaluated by measuring fresh and dry plant biomass, carotenoid and chlorophyll content, antioxidant enzyme activity, and concentrations of PO 4 3- , K + , and Na + in plant tissues. The addition of low concentrations of fertilizer increased dry mass, protein, and carotenoid content relative to controls, suggesting a beneficial effect on plants. The highest NaCl treatment (2560 mg L -1 ) resulted in increased Na + and protein content relative to control plants, as well as reduced PO 4 3- , K + , and chlorophyll levels and reduced catalase and ascorbate peroxidase enzyme activity levels. Analysis of life table data of T. urticae mites raised on leaves from the aforementioned plant groups showed the intrinsic rate of increase (r) for mites was 0.167 day -1 in control specimens, 0.125 day -1 for mites reared on plants treated with a moderate concentration of fertilizer (10 mL L -1 ), and was highest (0.241 day -1 ) on plants grown under moderate salinity conditions (1920 mg L -1 NaCl). Reproductive success of T. urticae did not differ on plants watered with a moderate concentration of NaCl or a high concentration of fertilizer. The moderately-stressed plants formed a favorable environment for the development and reproduction of spider mites, supporting the plant stress hypothesis.

A feeding protocol for delivery of agents to assess development in Varroa mites

USDA-ARS?s Scientific Manuscript database

A novel feeding protocol for delivery of bio-active agents to Varroa mites was developed by providing mites with honey bee larva hemolymph supplemented with cultured insect cells and selected materials suspended delivered on a fibrous cotton substrate. Mites were starved, fed on treated hemolymph to...

Spectral response of spider mite infested cotton: Mite density and miticide rate study

USDA-ARS?s Scientific Manuscript database

Two-spotted spider mites are important pests in many agricultural systems. Spider mites (Acari: Tetranychidae) have been found to cause economic damage in corn, cotton, and sorghum. Adult glass vial bioassays indicate that Temprano™ (abamectin) is the most toxic technical miticide for adult two-spot...

Responses to Varroa by honey bees with different levels of Varroa Sensitive Hygiene

USDA-ARS?s Scientific Manuscript database

The mite-resistance trait called suppression of mite reproduction (SMR) is a form of hygienic behavior that we have named varroa sensitive hygiene (VSH). With VSH, adult worker bees (Apis mellifera) disrupt the population growth of parasitic mites (Varroa destructor) by removing mite-infested bee p...

Avocado pests in Florida: Not what you expected

USDA-ARS?s Scientific Manuscript database

Avocado, Persea americana Mill., is Florida's second most important fruit crop after citrus. Until recently, the complex of spider mite and insect pests that affected avocado in south Florida was under a 20 year Integrated Pest Management (IPM) program. The recent invasion of avocado orchards by a...

A survey of fur mites in domestic rabbits.

PubMed

Flatt, R E; Wiemers, J

1976-10-01

A survey of six commercial rabbit colonies was conducted to determine the prevalence of the mite Cheyletiella parasitvorax. This mite was present in all six colonies, and 43.2% of 220 rabbits examined were infested. Listrophorus gibbus, reported only once previously in domestic rabbits in the United States, was found in four of the six colonies, and in 7.3% of the 220 rabbits examined. Non-parasitic mites were found in 3.2% of the samples. Over 50% of the rabbits examined had inapparent mite infestations.

Clinical benefits of treatment with SQ house dust mite sublingual tablet in house dust mite allergic rhinitis.

PubMed

Demoly, P; Kleine-Tebbe, J; Rehm, D

2017-10-01

Treatment with SQ (standardised quality) house dust mite sublingual tablet for 1 year resulted in a decreased probability of having an allergic rhinitis (AR) exacerbation day (from 11% [placebo] to 5% [SQ house dust mite sublingual tablet]) and an increased probability of having a mild AR day (from 16% [placebo] to 34% [SQ house dust mite sublingual tablet]). © 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

Large-bodied Demodex mite infestation in 4 dogs.

PubMed

Hillier, Andrew; Desch, Clifford E

2002-03-01

Large-bodied Demodex mites were detected in 4 dogs. The mites were readily detected in material obtained via deep skin scrapings and were most commonly found on the trunk. The mites were distinguishable from D. canis, because adult males were approximately 100% longer and adult females were approximately 50% longer than adult male and female D. canis mites, respectively. The large-bodied mites were found in the hair follicles, sebaceous ducts, and sebaceous glands in histologic sections of skin from 2 dogs. All dogs had adult-onset generalized demodicosis. Two dogs had coexistent iatrogenic hypercortisolism, 1 dog had hypothyroidism, and 1 dog did not have coexistent disease. Infestations responded to miticidal therapy, control of the coexistent disease, or both.

Natural biological control of pest mites in Brazilian sun coffee agroecosystems.

PubMed

Teodoro, Adenir V; Sarmento, Renato A; Rêgo, Adriano S; da Graça S Maciel, Anilde

2010-06-01

Coffee is one of the leading commodities in tropical America. Although plantations are usually established under a canopy of trees in most producing countries in the region, Brazilian coffee is mostly produced under full sun conditions. Such simple, single-crop agroecosystems with intensive agrochemical inputs often suffer with pests like mites. Predatory mites of the family Phytoseiidae are the main natural enemies associated with pest mites in the field. However, these beneficial arthropods struggle to survive in intensive agroecosystems such as coffee monocultures due to unfavorable microclimatic conditions, widespread pesticide use, and lack of alternative food (pollen, nectar). Conservation biological control uses a range of management strategies to sustain and enhance populations of indigenous natural enemies such as predatory mites. We discuss here conservation biological control as a strategy to improve biological control of pest mites by native predatory mites in Brazilian coffee monocultures as well as some related patents.

MITE ANTIGEN CONCENTRATIONS IN HOUSE DUST AND THE OCCURRENCE OF WHEEZING IN CHILDREN WITH MITE DUST ALLERGY

EPA Science Inventory

We studied the relationship between dust mite antigen concentrations in house dust samples and the occurrence and frequency of wheezing in 58 children with dust mite allergy (wheal > 4 mm. mean diameter in response to a prick test with either D-. farinae or D pteronyssinus antige...

Key Mites Commonly Associated With the Southern Pine Beetle

Treesearch

D.N. Kinn

1976-01-01

This paper outlines a method of preparing mites for microscopic examination and contains a simple key to the 15 species of mites commonly associated with the southern pine bark beetle. Research workers wanting to identify these mites and others curious about them, but untrained in acarology, should find little difficulty in making identifications.

Wheat streak mosaic virus coat protein is a determinant for vector transmission by the wheat curl mite

USDA-ARS?s Scientific Manuscript database

Wheat streak mosaic virus (WSMV; genus Tritimovirus; family Potyviridae), is transmitted by the wheat curl mite (Aceria tosichella Keifer). The requirement of coat protein (CP) for WSMV transmission by the wheat curl mite was examined using a series of viable deletion and point mutations. Mite trans...

Wheat curl mite and dry bulb mite: untangling a taxonomic conundrum through a multidisciplinary approach

USDA-ARS?s Scientific Manuscript database

The taxonomy of two economically important eriophyoid species, Aceria tosichella (wheat curl mite, WCM) and A. tulipae (dry bulb mite, DBM), was confounded in the world literature until the late 20th century due to their morphological similarity and ambiguous data from plant-transfer and virus-trans...

First plant-parasitic mites (acari: eriophyoidea) recorded from Svalbard, including the description of a new species

USDA-ARS?s Scientific Manuscript database

Eriophyoidea are minute phytophagous mites with great economic importance and great invasive potential. In spite of their impact on ecosystem functions, the knowledge of eriophyoid mites fauna in Arctic is lacking. Until now, only eight eriophyoid mite species were known from this region. Svalbard a...

Pheromonal Communication in the European House Dust Mite, Dermatophagoides pteronyssinus

PubMed Central

Steidle, Johannes L.M.; Barcari, Elena; Hradecky, Marc; Trefz, Simone; Tolasch, Till; Gantert, Cornelia; Schulz, Stefan

2014-01-01

Despite the sanitary importance of the European house dust mite Dermatophagoides pteronyssinus (Trouessart, 1897), the pheromonal communication in this species has not been sufficiently studied. Headspace analysis using solid phase micro extraction (SPME) revealed that nerol, neryl formate, pentadecane, (6Z,9Z)-6,9-heptadecadiene, and (Z)-8-heptadecene are released by both sexes whereas neryl propionate was released by males only. Tritonymphs did not produce any detectable volatiles. In olfactometer experiments, pentadecane and neryl propionate were attractive to both sexes as well as to tritonymphs. (Z)-8-heptadecene was only attractive to male mites. Therefore it is discussed that pentadecane and neryl propionate are aggregation pheromones and (Z)-8-heptadecene is a sexual pheromone of the European house dust mite D. pteronyssinus. To study the potential use of pheromones in dust mite control, long-range olfactometer experiments were conducted showing that mites can be attracted to neryl propionate over distances of at least 50 cm. This indicates that mite pheromones might be useable to monitor the presence or absence of mites in the context of control strategies. PMID:26462831

Recent amplification and impact of MITEs on the genome of grapevine (Vitis vinifera L.)

PubMed Central

Benjak, Andrej; Boué, Stéphanie; Forneck, Astrid

2009-01-01

Miniature inverted-repeat transposable elements (MITEs) are a particular type of defective class II transposons present in genomes as highly homogeneous populations of small elements. Their high copy number and close association to genes make their potential impact on gene evolution particularly relevant. Here, we present a detailed analysis of the MITE families directly related to grapevine “cut-and-paste” transposons. Our results show that grapevine MITEs have transduplicated and amplified genomic sequences, including gene sequences and fragments of other mobile elements. Our results also show that although some of the MITE families were already present in the ancestor of the European and American Vitis wild species, they have been amplified and have been actively transposing accompanying grapevine domestication and breeding. We show that MITEs are abundant in grapevine and some of them are frequently inserted within the untranslated regions of grapevine genes. MITE insertions are highly polymorphic among grapevine cultivars, which frequently generate transcript variability. The data presented here show that MITEs have greatly contributed to the grapevine genetic diversity which has been used for grapevine domestication and breeding. PMID:20333179

Chigger Mite (Acari: Trombiculidae) Survey of Rodents in Shandong Province, Northern China

PubMed Central

Huang, Xiao-Dan; Cheng, Peng; Zhao, Yu-Qiang; Li, Wen-Juan; Zhao, Jiu-Xu; Liu, Hong-Mei; Kou, Jing-Xuan; Gong, Mao-Qing

2017-01-01

Chigger mites are parasites of rodents and other vertebrates, invertebrates, and other arthropods, and are the only vectors of scrub typhus, in addition to other zoonoses. Therefore, investigating their distribution, diversity, and seasonal abundance is important for public health. Rodent surveillance was conducted at 6 districts in Shandong Province, northern China (114–112°E, 34–38°N), from January to December 2011. Overall, 225/286 (78.7%) rodents captured were infested with chigger mites. A total of 451 chigger mites were identified as belonging to 5 most commonly collected species and 3 genera in 1 family. Leptotrombidium scutellare and Leptotrombidium intermedia were the most commonly collected chigger mites. L. scutellare (66.2%, 36.7%, and 49.0%) was the most frequently collected chigger mite from Apodemus agrarius, Rattus norvegicus, and Microtus fortis, respectively, whereas L. intermedia (61.5% and 63.2%) was the most frequently collected chigger mite from Cricetulus triton and Mus musculus, respectively. This study demonstrated a relatively high prevalence of chigger mites that varied seasonally in Shandong Province, China. PMID:29103271

Chigger Mite (Acari: Trombiculidae) Survey of Rodents in Shandong Province, Northern China.

PubMed

Huang, Xiao-Dan; Cheng, Peng; Zhao, Yu-Qiang; Li, Wen-Juan; Zhao, Jiu-Xu; Liu, Hong-Mei; Kou, Jing-Xuan; Gong, Mao-Qing

2017-10-01

Chigger mites are parasites of rodents and other vertebrates, invertebrates, and other arthropods, and are the only vectors of scrub typhus, in addition to other zoonoses. Therefore, investigating their distribution, diversity, and seasonal abundance is important for public health. Rodent surveillance was conducted at 6 districts in Shandong Province, northern China (114-112°E, 34-38°N), from January to December 2011. Overall, 225/286 (78.7%) rodents captured were infested with chigger mites. A total of 451 chigger mites were identified as belonging to 5 most commonly collected species and 3 genera in 1 family. Leptotrombidium scutellare and Leptotrombidium intermedia were the most commonly collected chigger mites. L. scutellare (66.2%, 36.7%, and 49.0%) was the most frequently collected chigger mite from Apodemus agrarius, Rattus norvegicus, and Microtus fortis, respectively, whereas L. intermedia (61.5% and 63.2%) was the most frequently collected chigger mite from Cricetulus triton and Mus musculus, respectively. This study demonstrated a relatively high prevalence of chigger mites that varied seasonally in Shandong Province, China.

Two simple techniques for the safe Sarcoptes collection and individual mite DNA extraction.

PubMed

Soglia, Dominga; Rambozzi, Luisa; Maione, Sandra; Spalenza, Veronica; Sartore, Stefano; Alasaad, Samer; Sacchi, Paola; Rossi, Luca

2009-10-01

Availability of mites is a recognized limiting factor of biological and genetic investigations of the genus Sarcoptes. Current methods of deoxyribonucleic acid (DNA) extraction from individual mites also need substantial improvement in efficiency and operator friendliness. We have first developed a technique for efficient and safe extraction of living mites from scabietic skin samples (crusts or deep skin scrapings). Its core device is a large plastic syringe connected with a 1.5-ml Eppendorf tube. The source material is introduced in the syringe and the device in a shoe box with the tip half of the tube emerging. Mites migrate towards a heat source during a minimum of 36 h. Then, the tube is detached and the mites utilized without risks for the operators. A second technique allows operator-friendly manipulation of individual mites for DNA extraction. Fixed mites are isolated by adhesion to a small strip of polyvinyl chloride (PVC) adhesive tape operated with tweezers. Then, mite and strip are plunged in the lyses buffer and the sample twice submitted to thermal shock for disruption of the chitinous exoskeleton. Data show that the tape does not interfere with successive DNA extraction with a commercial kit. The corresponding protocol, that we briefly name "PVC adhesive tape + thermal shock + kit DNA extraction," compares favorably with the available ones.

The influence of air conditioning, humidity, temperature and other household characteristics on mite allergen concentrations in the northeastern United States.

PubMed

van Strien, R T; Gehring, U; Belanger, K; Triche, E; Gent, J; Bracken, M B; Leaderer, B P

2004-06-01

Information about the influence of housing and occupant characteristics on mite allergen concentrations is crucial to determine which methods could be used to decrease exposure of susceptible subjects. To identify housing and occupant characteristics that are associated with mite allergen concentrations in house dust collected from living rooms and mattresses. We collected dust samples from 750 homes in the northeastern US. The influence of various characteristics on concentrations of mite allergens (Der p 1 and Der f 1) was studied using multiple linear regression analysis. Some characteristics, like absence of air conditioners, the presence of mold or mildew, and a lower temperature were consistently associated with higher concentrations of both mite allergens in dust from all sampling locations. However, none of these factors changed Der p 1 or Der f 1 concentrations by more than a factor of 2. People of white ethnic background had roughly two times higher mite allergen concentrations, while family income, family size, and education level only marginally influenced mite allergen concentrations. Various housing characteristics have some influence on mite allergen concentrations, and could possibly be used to decrease exposure of susceptible subjects. However, only a limited percentage of the variation in mite allergen concentrations was explained by these characteristics.

Impacts of twenty years of experimental warming on soil carbon, nitrogen, moisture and soil mites across alpine/subarctic tundra communities.

PubMed

Alatalo, Juha M; Jägerbrand, Annika K; Juhanson, Jaanis; Michelsen, Anders; Ľuptáčik, Peter

2017-03-15

High-altitude and alpine areas are predicted to experience rapid and substantial increases in future temperature, which may have serious impacts on soil carbon, nutrient and soil fauna. Here we report the impact of 20 years of experimental warming on soil properties and soil mites in three contrasting plant communities in alpine/subarctic Sweden. Long-term warming decreased juvenile oribatid mite density, but had no effect on adult oribatids density, total mite density, any major mite group or the most common species. Long-term warming also caused loss of nitrogen, carbon and moisture from the mineral soil layer in mesic meadow, but not in wet meadow or heath or from the organic soil layer. There was a significant site effect on the density of one mite species, Oppiella neerlandica, and all soil parameters. A significant plot-scale impact on mites suggests that small-scale heterogeneity may be important for buffering mites from global warming. The results indicated that juvenile mites may be more vulnerable to global warming than adult stages. Importantly, the results also indicated that global warming may cause carbon and nitrogen losses in alpine and tundra mineral soils and that its effects may differ at local scale.

Mite communities (Acari: Mesostigmata) in young and mature coniferous forests after surface wildfire.

PubMed

Kamczyc, Jacek; Urbanowski, Cezary; Pers-Kamczyc, Emilia

2017-06-01

Density, diversity and assemblage structure of Mesostigmata (cohorts Gamasina and Uropodina) were investigated in Scots pine forests differing in forest age (young: 9-40 years and mature: 83-101 years) in which wildfire occurred. This animal group belongs to the dominant acarine predators playing a crucial role in soil food webs and being important as biological control agents. In total, six forests (three within young and three within mature stands) were inspected in Puszcza Knyszyńska Forest Complex in May 2015. At each forest area, sampling was done from burned and adjacent control sites with steel cylinders for heat extraction of soil fauna. Data were analyzed statistically with nested ANOVA. We found a significant effect on mite density of both fire and forest age, with more mites in mature forests and control plots. In total, 36 mite taxa were identified. Mite diversity differed significantly between forest ages but not between burned versus control. Our study indicated that all studied forests are characterized by unique mite species and that the mite communities are dominated by different mite species depending on age forest and surface wildfire occurrence. Finally, canonical correspondence analysis ranked the mite assemblages from control mature, through burned young and burned mature, away from the control young.

An Aspartic Protease of the Scabies Mite Sarcoptes scabiei Is Involved in the Digestion of Host Skin and Blood Macromolecules

PubMed Central

Mahmood, Wajahat; Viberg, Linda T.; Fischer, Katja; Walton, Shelley F.; Holt, Deborah C.

2013-01-01

Background Scabies is a disease of worldwide significance, causing considerable morbidity in both humans and other animals. The scabies mite Sarcoptes scabiei burrows into the skin of its host, obtaining nutrition from host skin and blood. Aspartic proteases mediate a range of diverse and essential physiological functions such as tissue invasion and migration, digestion, moulting and reproduction in a number of parasitic organisms. We investigated whether aspartic proteases may play role in scabies mite digestive processes. Methodology/Principle Findings We demonstrated the presence of aspartic protease activity in whole scabies mite extract. We then identified a scabies mite aspartic protease gene sequence and produced recombinant active enzyme. The recombinant scabies mite aspartic protease was capable of digesting human haemoglobin, serum albumin, fibrinogen and fibronectin, but not collagen III or laminin. This is consistent with the location of the scabies mites in the upper epidermis of human skin. Conclusions/Significance The development of novel therapeutics for scabies is of increasing importance given the evidence of emerging resistance to current treatments. We have shown that a scabies mite aspartic protease plays a role in the digestion of host skin and serum molecules, raising the possibility that interference with the function of the enzyme may impact on mite survival. PMID:24244770

Challenges in devising economic spray thresholds for a major pest of Australian canola, the redlegged earth mite (Halotydeus destructor).

PubMed

Arthur, Aston L; Hoffmann, Ary A; Umina, Paul A

2015-10-01

A key component for spray decision-making in IPM programmes is the establishment of economic injury levels (EILs) and economic thresholds (ETs). We aimed to establish an EIL for the redlegged earth mite (Halotydeus destructor Tucker) on canola. Complex interactions between mite numbers, feeding damage and plant recovery were found, highlighting the challenges in linking H. destructor numbers to yield. A guide of 10 mites plant(-1) was established at the first-true-leaf stage; however, simple relationships were not evident at other crop development stages, making it difficult to establish reliable EILs based on mite number. Yield was, however, strongly associated with plant damage and plant densities, reflecting the impact of mite feeding damage and indicating a plant-based alternative for establishing thresholds for H. destructor. Drawing on data from multiple field trials, we show that plant densities below 30-40 plants m(-2) could be used as a proxy for mite damage when reliable estimates of mite densities are not possible. This plant-based threshold provides a practical tool that avoids the difficulties of accurately estimating mite densities. The approach may be applicable to other situations where production conditions are unpredictable and interactions between pests and plant hosts are complex. © 2015 Society of Chemical Industry.

First detections of Rickettsia helvetica and R. monacensis in ectoparasitic mites (Laelapidae and Trombiculidae) infesting rodents in south-western Slovakia.

PubMed

Miťková, Katarína; Berthová, Lenka; Kalúz, Stanislav; Kazimírová, Mária; Burdová, Lenka; Kocianová, Elena

2015-07-01

Information on circulation of rickettsiae between small mammals and their ectoparasitic mites is scarce. In this study, we investigated infestation rates of rodents with mites in some areas of SW Slovakia and the role of mites as possible vectors of pathogenic rickettsiae. A total of 615 rodents of five species were caught during 2010-2012. All individuals were examined for ectoparasites which resulted in 2821 mites belonging to three species of Laelapidae and six species of Trombiculidae. The most common Laelapidae species was Laelaps agilis (81.25 %), followed by Haemogamasus nidi, and Eulaelaps stabularis. Hirsutiella zachvatkini (16.52 %) was the dominant species of the family Trombiculidae. DNA extracted from rodent blood and ectoparasitic mites was examined for the presence of rickettsiae by PCR. By pooling mites, 345 pool samples were created, of which 112 (32.46 %) were found to be positive for the rickettsial DNA. From 487 examined rodent blood samples, rickettsial DNA was found in 46 (9.44 %). Sequencing DNA from the positive blood samples and mites revealed the identity of Rickettsia helvetica and Rickettsia monacensis. The results of the study suggest that ectoparasitic mites may be reservoirs as well as vectors of some pathogenic rickettsiae.

Impacts of twenty years of experimental warming on soil carbon, nitrogen, moisture and soil mites across alpine/subarctic tundra communities

NASA Astrophysics Data System (ADS)

Alatalo, Juha M.; Jägerbrand, Annika K.; Juhanson, Jaanis; Michelsen, Anders; Ľuptáčik, Peter

2017-03-01

High-altitude and alpine areas are predicted to experience rapid and substantial increases in future temperature, which may have serious impacts on soil carbon, nutrient and soil fauna. Here we report the impact of 20 years of experimental warming on soil properties and soil mites in three contrasting plant communities in alpine/subarctic Sweden. Long-term warming decreased juvenile oribatid mite density, but had no effect on adult oribatids density, total mite density, any major mite group or the most common species. Long-term warming also caused loss of nitrogen, carbon and moisture from the mineral soil layer in mesic meadow, but not in wet meadow or heath or from the organic soil layer. There was a significant site effect on the density of one mite species, Oppiella neerlandica, and all soil parameters. A significant plot-scale impact on mites suggests that small-scale heterogeneity may be important for buffering mites from global warming. The results indicated that juvenile mites may be more vulnerable to global warming than adult stages. Importantly, the results also indicated that global warming may cause carbon and nitrogen losses in alpine and tundra mineral soils and that its effects may differ at local scale.

Ecology, Life History, and Management of Tropilaelaps Mites.

PubMed

de Guzman, Lilia I; Williams, Geoffrey R; Khongphinitbunjong, Kitiphong; Chantawannakul, Panuwan

2017-04-01

Parasitic mites are the major threat to the Western honey bee, Apis mellifera L. For much of the world, Varroa destructor Anderson & Trueman single-handedly inflicts unsurmountable problems to A. mellifera beekeeping. However, A. mellifera in Asia is also faced with another genus of destructive parasitic mite, Tropilaelaps. The life history of these two parasitic mites is very similar, and both have the same food requirements (i.e., hemolymph of developing brood). Hence, parasitism by Tropilaelaps spp., especially Tropilaelaps mercedesae and Tropilaelaps clareae, also results in death of immature brood or wing deformities in infested adult bees. The possible introduction of Tropilaelaps mites outside their current range heightens existing dilemmas brought by Varroa mites. In this review, we provide historic, as well as current information on the taxonomic status, life history, distribution and host range, diagnosis, and control of Tropilaelaps mites. Because the biology of Tropilaelaps mites is not well known, we also suggest areas of research that demand immediate attention. Any biological information about Tropilaelaps mites will provide useful information for the development of control measures against them. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by US Government employees and is in the public domain in the US.

Factors affecting the distribution of a predatory mite on greenhouse sweet pepper.

PubMed

Weintraub, Phyllis G; Kleitman, Sophia; Alchanatis, Victor; Palevsky, Eric

2007-01-01

The predatory mite Neoseiulus cucumeris is used for biological control of phytophagous mites and thrips on greenhouse cucumber and sweet pepper. In a previous study, N. cucumeris provided effective control of broad mite but was only rarely found on the sampled leaves, raising questions about the factors affecting N. cucumeris distribution. To determine the distribution of N. cucumeris, leaves of pepper plants were sampled three times per day: just after sunrise, at noon and just before sunset for two years and throughout a 24 h period in one year. The presence of other mites and insects was recorded. Biotic (pollen) and abiotic (temperature, humidity) factors were monitored from the three plant levels. The effect of direct and indirect sunlight on the mites was assessed. N. cucumeris was found primarily in flowers; however, the mite's distribution was affected by other predators (intraguild predation); in the presence of the predatory bug Orius laevigatus virtually no mites occurred in the flowers. Whereas temperature and humidity varied from the top to the lower level of the plants, apparently neither these factors nor the presence of pollen outside the flowers influenced mite distribution. N. cucumeris was found to be negatively phototropic; therefore N. cucumeris were pre-conditioned to light by rearing under light conditions for 4 months before being released. The light-reared mites were initially more numerous during the noon sampling period, however, rearing conditions caused only a temporary and non-significant change in distribution.

Mite and pet allergen levels in homes of children born to allergic and nonallergic parents: the PIAMA study.

PubMed

van Strien, Rob T; Koopman, Laurens P; Kerkhof, Marjan; Spithoven, Jack; de Jongste, Johan C; Gerritsen, Jorrit; Neijens, Herman J; Aalberse, Rob C; Smit, Henriette A; Brunekreef, Bert

2002-11-01

The Prevention and Incidence of Asthma and Mite Allergy (PIAMA) study is a birth cohort study that investigates the influence of allergen exposure on the development of allergy and asthma in the first several years of life. The objectives of this study were to investigate the relationship between a family history of allergy and/or asthma and exposure of newborn children to mite and pet allergen and to study the influence of different home and occupant characteristics on mite allergen exposure. Dust was sampled from the child's mattress and the parental mattress at 3 months after birth of the index child and analyzed for mite and pet allergens. Subjects were divided in groups according to history of asthma and allergy in their parents, and allergen exposure was studied in the different groups. Cat allergen exposure was significantly lower on parental mattresses in families with allergic mothers, but dog allergen exposure was not different. Mite allergen exposure was lower on parental mattresses in families with allergic mothers. Use of mite allergen-impermeable mattress covers reduced mite allergen exposure. Some other characteristics such as age of home and mattress were also found to influence mite allergen exposure. Parental mattresses in homes of allergic mothers had lower cat and mite (but not dog) allergen loadings than mattresses in homes of nonallergic parents. Paternal (as opposed to maternal) allergy seemed to have little influence.

High Gama-Aminobutyric Acid Contents Involved in Abamectin Resistance and Predation, an Interesting Phenomenon in Spider Mites

PubMed Central

Xu, Zhifeng; Liu, Yanchao; Wei, Peng; Feng, Kaiyang; Niu, Jinzhi; Shen, Guangmao; Lu, Wencai; Xiao, Wei; Wang, Jinjun; Smagghe, Guy J.; Xu, Qiang; He, Lin

2017-01-01

Abamectin has been widely used as an insecticide/acaricide for more than 30 years because of its superior bioactivity. Recently, an interesting phenomenon was identified in the carmine spider mite, Tetranychus cinnabarinus, an important pest in agriculture. The gamma aminobutyric acid (GABA) contents in a laboratory abamectin resistant strain of T. cinnabarinus (AbR) were significantly increased. Decreases in activity and mRNA expression of GABA transaminase (GABA-T) were responsible for GABA accumulation in AbR mites. To clarify the mechanism of GABA accumulation mediated abamectin resistance, three artificial approaches were conducted to increase GABA contents in susceptible mites, including feeding of vigabatrin (a specific inhibitor of GABA-T), feeding of exogenous GABA, and inhibition of GABA-T gene expression. The results showed that susceptible mites developed resistance to abamectin when the GABA contents were artificially increased. We also observed that the mites with higher GABA contents moved more slowly, which is consistent with the fact that GABA is an inhibitory neurotransmitter in arthropods. Subsequently, functional response assays revealed that predation rates of predatory mites on GABA accumulated abamectin-resistant mites were much higher than control groups. The tolerance to abamectin, slow crawling speed, and vulnerability to predators were all resulted from GABA accumulation. This relationship between GABA and predation was also confirmed in a field-collected population. Our finding indicates that predatory mites might be used as a tool for biological control to circumvent the development of abamectin resistance in mites. PMID:28443033

The effect of herbivore faeces on the edaphic mite community: implications for tapeworm transmission.

PubMed

Václav, Radovan; Kalúz, Stanislav

2014-03-01

Oribatid mites may be of epidemiological and medical importance because several species have been shown to serve as intermediate hosts for anoplocephalid tapeworms of wild and domestic animals. Despite their economic and conservation significance, relatively few studies examined factors influencing the effective number of oribatid mites that can serve as intermediate hosts. We examined variation in the structure of the edaphic arthropod community in functionally different territory parts of the Alpine marmot (Marmota marmota latirostris), a known definitive host of a prevalent anoplocephalid tapeworm, Ctenotaenia marmotae. We used a field experiment to test whether the abundance of oribatid mites in marmot pastures is affected by the presence of fresh herbivore faeces. We found that the abundance of soil and litter dwelling oribatid mites in marmot pastures did not change shortly after faeces addition. In contrast, numbers of other predominant soil-litter and phoretic microarthropods increased after faeces addition. The abundance of the two predominant phoretic mites colonizing the faeces was inversely related to the abundance of oribatid mites. In contrast, the abundance of a ubiquitous soil-litter mesostigmatid mite was a positive function of oribatid numbers. Although absolute numbers of oribatid mites did not change after faeces addition, our study suggests that, depending on soil quality or type, the probability of tapeworm egg ingestion by oribatid mites can be reduced due to increased interspecific prey-predatory and trophic interactions. Latrine site selection in Alpine marmots is consistent with a reduced probability of tapeworm transmission by oribatids.

High Gama-Aminobutyric Acid Contents Involved in Abamectin Resistance and Predation, an Interesting Phenomenon in Spider Mites.

PubMed

Xu, Zhifeng; Liu, Yanchao; Wei, Peng; Feng, Kaiyang; Niu, Jinzhi; Shen, Guangmao; Lu, Wencai; Xiao, Wei; Wang, Jinjun; Smagghe, Guy J; Xu, Qiang; He, Lin

2017-01-01

Abamectin has been widely used as an insecticide/acaricide for more than 30 years because of its superior bioactivity. Recently, an interesting phenomenon was identified in the carmine spider mite, Tetranychus cinnabarinus , an important pest in agriculture. The gamma aminobutyric acid (GABA) contents in a laboratory abamectin resistant strain of T. cinnabarinus (AbR) were significantly increased. Decreases in activity and mRNA expression of GABA transaminase (GABA-T) were responsible for GABA accumulation in AbR mites. To clarify the mechanism of GABA accumulation mediated abamectin resistance, three artificial approaches were conducted to increase GABA contents in susceptible mites, including feeding of vigabatrin (a specific inhibitor of GABA-T), feeding of exogenous GABA, and inhibition of GABA-T gene expression. The results showed that susceptible mites developed resistance to abamectin when the GABA contents were artificially increased. We also observed that the mites with higher GABA contents moved more slowly, which is consistent with the fact that GABA is an inhibitory neurotransmitter in arthropods. Subsequently, functional response assays revealed that predation rates of predatory mites on GABA accumulated abamectin-resistant mites were much higher than control groups. The tolerance to abamectin, slow crawling speed, and vulnerability to predators were all resulted from GABA accumulation. This relationship between GABA and predation was also confirmed in a field-collected population. Our finding indicates that predatory mites might be used as a tool for biological control to circumvent the development of abamectin resistance in mites.

Community structure, trophic position and reproductive mode of soil and bark-living oribatid mites in an alpine grassland ecosystem.

PubMed

Fischer, Barbara M; Schatz, Heinrich; Maraun, Mark

2010-11-01

The community structure, stable isotope ratios ((15)N/(14)N, (13)C/(12)C) and reproductive mode of oribatid mites (Acari, Oribatida) were investigated in four habitats (upper tree bark, lower tree bark, dry grassland soil, forest soil) at two sites in the Central Alps (Tyrol, Austria). We hypothesized that community structure and trophic position of oribatid mites of dry grassland soils and bark of trees are similar since these habitats have similar abiotic characteristics (open, dry) compared with forest soil. Further, we hypothesized that derived taxa of oribatid mites reproducing sexually dominate on the bark of trees since species in this habitat consume living resources such as lichens. In contrast to our hypothesis, the community structure of oribatid mites differed among grassland, forest and bark indicating the existence of niche differentiation in the respective oribatid mite species. In agreement with our hypothesis, sexually reproducing taxa of oribatid mites dominated on the bark of trees whereas parthenogenetic species were more frequent in soil. Several species of bark-living oribatid mites had stable isotope signatures that were similar to lichens indicating that they feed on lichens. However, nine species that frequently occurred on tree bark did not feed on lichens according to their stable isotope signatures. No oribatid mite species could be ascribed to moss feeding. We conclude that sexual reproduction served as preadaptation for oribatid mites allowing them to exploit new habitats and new resources on the bark of trees. Abiotic factors likely are of limited importance for bark-living oribatid mites since harsh abiotic conditions are assumed to favor parthenogenesis.

Detection, Prevalence and Phylogenetic Relationships of Demodex spp and further Skin Prostigmata Mites (Acari, Arachnida) in Wild and Domestic Mammals.

PubMed

Sastre, Natalia; Francino, Olga; Curti, Joseph N; Armenta, Tiffany C; Fraser, Devaughn L; Kelly, Rochelle M; Hunt, Erin; Silbermayr, Katja; Zewe, Christine; Sánchez, Armand; Ferrer, Lluís

2016-01-01

This study was conceived to detect skin mites in social mammals through real-time qPCR, and to estimate taxonomic Demodex and further Prostigmata mite relationships in different host species by comparing sequences from two genes: mitochondrial 16S rRNA and nuclear 18S rRNA. We determined the mite prevalence in the hair follicles of marmots (13%) and bats (17%). The high prevalence found in marmots and bats by sampling only one site on the body may indicate that mites are common inhabitants of their skin. Since we found three different mites (Neuchelacheles sp, Myobia sp and Penthaleus sp) in three bat species (Miotis yumanensis, Miotis californicus and Corynorhinus townsendii) and two different mites (both inferred to be members of the Prostigmata order) in one marmot species (Marmota flaviventris), we tentatively concluded that these skin mites 1) cannot be assigned to the same genus based only on a common host, and 2) seem to evolve according to the specific habitat and/or specific hair and sebaceous gland of the mammalian host. Moreover, two M. yumanensis bats harbored identical Neuchelacheles mites, indicating the possibility of interspecific cross-infection within a colony. However, some skin mites species are less restricted by host species than previously thought. Specifically, Demodex canis seems to be more transmissible across species than other skin mites. D. canis have been found mostly in dogs but also in cats and captive bats. In addition, we report the first case of D. canis infestation in a domestic ferret (Mustela putorius). All these mammalian hosts are related to human activities, and D. canis evolution may be a consequence of this relationship. The monophyletic Demodex clade showing closely related dog and human Demodex sequences also supports this likely hypothesis.

Detection, Prevalence and Phylogenetic Relationships of Demodex spp and further Skin Prostigmata Mites (Acari, Arachnida) in Wild and Domestic Mammals

PubMed Central

Sastre, Natalia; Francino, Olga; Curti, Joseph N.; Armenta, Tiffany C.; Fraser, Devaughn L.; Kelly, Rochelle M.; Hunt, Erin; Silbermayr, Katja; Zewe, Christine; Sánchez, Armand; Ferrer, Lluís

2016-01-01

This study was conceived to detect skin mites in social mammals through real-time qPCR, and to estimate taxonomic Demodex and further Prostigmata mite relationships in different host species by comparing sequences from two genes: mitochondrial 16S rRNA and nuclear 18S rRNA. We determined the mite prevalence in the hair follicles of marmots (13%) and bats (17%). The high prevalence found in marmots and bats by sampling only one site on the body may indicate that mites are common inhabitants of their skin. Since we found three different mites (Neuchelacheles sp, Myobia sp and Penthaleus sp) in three bat species (Miotis yumanensis, Miotis californicus and Corynorhinus townsendii) and two different mites (both inferred to be members of the Prostigmata order) in one marmot species (Marmota flaviventris), we tentatively concluded that these skin mites 1) cannot be assigned to the same genus based only on a common host, and 2) seem to evolve according to the specific habitat and/or specific hair and sebaceous gland of the mammalian host. Moreover, two M. yumanensis bats harbored identical Neuchelacheles mites, indicating the possibility of interspecific cross-infection within a colony. However, some skin mites species are less restricted by host species than previously thought. Specifically, Demodex canis seems to be more transmissible across species than other skin mites. D. canis have been found mostly in dogs but also in cats and captive bats. In addition, we report the first case of D. canis infestation in a domestic ferret (Mustela putorius). All these mammalian hosts are related to human activities, and D. canis evolution may be a consequence of this relationship. The monophyletic Demodex clade showing closely related dog and human Demodex sequences also supports this likely hypothesis. PMID:27802314

Field efficacy of phoxim 50% (ByeMite) against the poultry red mite Dermanyssus gallinae in battery cages stocked with laying hens.

PubMed

Meyer-Kühling, Borris; Pfister, Kurt; Müller-Lindloff, Jürgen; Heine, Josef

2007-07-20

Infestations with the poultry red mite Dermanyssus gallinae represent a major ectoparasite problem in poultry and can affect egg layers worldwide. There is presently a lack of an ectoparasiticide in Europe for poultry which can assure a 0-day withholding period for eggs. In this study, ByeMite (phoxim 50%, Bayer HealthCare, Animal Health Division) was administered to treat a D. gallinae infestation in a poultry house stocked with egg-laying hens kept in a cage system. A layer house was sprayed twice within a 7-day interval using a solution containing 2000 ppm phoxim and a similar layer house was used as an untreated control unit. Specially developed D. gallinae traps made of cardboard were used to assess the mite density in both layer houses during a 49-day period after the treatment. In order to collect mites, the traps were placed on days--1, 2, 6, 9, 13, 20, 34 and 48 and always removed after 24 h. The collected mites were counted and differentiated according to their developmental stage (mite eggs, larvae, nymphs, adults). Three days after the first spray treatment, the efficacy against all mite stages (larvae, nymphs, adults) was 96.1%, and from day 7 post-treatment until the end of the trial (day 49) the efficacy exceeded 99%. In contrast, in the untreated layer house (negative control group) the mite population showed a 400% increase. No treatment-related side effects in chickens were detectable. It is concluded that two administrations of ByeMite within a 7-day interval are highly effective against D. gallinae infestations in a stocked poultry house.

Variability in Damage Caused by the Mite Tetranychus urticae (Trombidiformes: Tetranychidae) Koch on Three Varieties of Strawberry.

PubMed

González-Domínguez, S G; Santillán-Galicia, M T; González-Hernández, V; Suárez Espinosa, J; González-Hernández, H

2015-06-01

The strawberry, Fragaria×ananassa Duchesne (Rosales: Rosaceae), is an important crop in Mexico. We evaluated the tolerance of three newly developed Mexican strawberry varieties (CP0615, CPLE-7, and CPJacona) to Tetranychus urticae Koch (Trombidiformes: Tetranychidae), the most important pest of strawberry. We evaluated the effect of three different initial mite densities on population growth, duration of each developmental stage and survival of T. urticae on the three strawberry varieties. We also compared the photosynthetic activity (Pn), sub-stomatal CO2 concentration (Ci), stomatal conductance (gs) and the area of leaf damaged in the three varieties. The largest final density of mites occurred on the variety CP0615, followed by the varieties CPLE-7 and CPJacona. There were no significant differences in the duration of T. urticae developmental stages amongst the varieties, except for larvae where the shortest duration was on variety CPLE-7. The proportion of eggs reaching the adult stage (survival) was significantly lower on the variety CPLE-7. The number and morphology of the trichomes did not play an important role in the outcomes, as they were similar in the three varieties. There were no significant differences in Pn, Ci, and gs values amongst the three varieties in the presence and absence of T. urticae. The area of leaf damaged in variety CPLE-7 was significantly smaller than for the other varieties. Based on these results, and with regard to spider mite tolerance, we believe that the variety CPLE-7 has the greatest potential for further development, and eventually, for use on a commercial scale in Mexico. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Efficacy evaluation of a pollen blocker cream against dust-mite allergy: A multicenter, randomized, double-blind, placebo-controlled crossover trial.

PubMed

Li, Yanqing; Cheng, Lei; Chen, Xiaoning; Yang, Beibei; Wang, Dehui

2015-01-01

To further evaluate the efficacy and safety of a pollen blocker cream against dust-mite allergy. A multicenter, randomized, double-blind, placebo-controlled, crossover trial was conducted in a Chinese population. Patients diagnosed with perennial allergic rhinitis, sensitive to dust-mite allergy including Dermatophagoides farinae and Dermatophagoides pteronyssinus were randomly allocated to receive a pollen blocker cream or placebo, which was applied and spread evenly to the lower internal nose region three times daily for a total of 30 days. The primary outcome measurements for efficacy were total nasal symptom score (TNSS) and individual nasal symptom score (iNSS). Adverse events were also monitored. After application of a pollen blocker, the mean TNSS decreased from 23.1 to 13.8, the decrease of the pollen blocker group (9.3) was highly significant compared with the placebo group (5.2; p < 0.001). Similarly, the decreases in iNSSs (rhinorrhea, congestion, sneezing, and itching) between the pollen blocker group and the placebo group were also significant (p < 0.05). In addition, in adults, the pollen blocker led to a remarkably significant decrease in TNSS (9.5) compared with placebo (5.4; p < 0.001); in children, the pollen blocker led to a significant decrease in TNSS (8.6) compared with placebo (4.8; p < 0.05). No statistical difference was found in the incidence of adverse events between the two groups (p > 0.05), and no severe systematic reactions were observed. Pollen Blocker is a safe and effective alternative to the drugs for treatment of AR, especially for Chinese people allergic to dust-mite allergy.

Phylogenetic relationships, stage-specific expression and localisation of a unique family of inactive cysteine proteases in Sarcoptes scabiei.

PubMed

Fernando, Deepani D; Reynolds, Simone L; Zakrzewski, Martha; Mofiz, Ehtesham; Papenfuss, Anthony T; Holt, Deborah; Fischer, Katja

2018-05-16

Scabies is worldwide one of the most common, yet neglected, parasitic skin infections, affecting a wide range of mammals including humans. Limited treatment options and evidence of emerging mite resistance against the currently used drugs drive our research to explore new therapeutic candidates. Previously, we discovered a multicopy family of genes encoding cysteine proteases with their catalytic sites inactivated by mutation (SMIPP-Cs). This protein family is unique in parasitic scabies mites and is absent in related non-burrowing mites. We postulated that the SMIPP-Cs have evolved as an adaptation to the parasitic lifestyle of the scabies mite. To formulate testable hypotheses for their functions and to propose possible strategies for translational research we investigated whether the SMIPP-Cs are common to all scabies mite varieties and where within the mite body as well as when throughout the parasitic life-cycle they are expressed. SMIPP-C sequences from human, pig and dog mites were analysed bioinformatically and the phylogenetic relationships between the SMIPP-C multi-copy gene families of human, pig and dog mites were established. Results suggest that amplification of the SMIPP-C genes occurred in a common ancestor and individual genes evolved independently in the different mite varieties. Recombinant human mite SMIPP-C proteins were produced and used for murine polyclonal antibody production. Immunohistology on skin sections from human patients localised the SMIPP-Cs in the mite gut and in mite faeces within in the epidermal skin burrows. SMIPP-C transcription into mRNA in different life stages was assessed in human and pig mites by reverse transcription followed by droplet digital PCR (ddPCR). High transcription levels of SMIPP-C genes were detected in the adult female life stage in comparison to all other life stages. The fact that the SMIPP-Cs are unique to three Sarcoptes varieties, present in all burrowing life stages and highly expressed in the digestive system of the infective adult female life stage may highlight an essential role in parasitism. As they are excreted from the gut in scybala they presumably are able to interact or interfere with host proteins present in the epidermis.

Evaluation of drone brood removal for management of Varroa destructor (Acari: Varroidae) in colonies of Apis mellifera (Hymenoptera: Apidae) in the northeastern United States.

PubMed

Calderone, N W

2005-06-01

The efficacy of drone brood removal for the management of Varroa destructor Anderson & Trueman in colonies of the honey bee, A. mellifera L., was evaluated. Colonies were treated with CheckMite+ in the fall of 2002. The following spring, quantities of bees and brood were equalized, but colonies were not retreated. The brood nest of each colony consisted of 18 full-depth worker combs and two full-depth drone combs. Each worker comb had <12.9 cm2 of drone cells. Standard management practices were used throughout the season. Colonies were randomly assigned to one of two groups. In the control group, drone combs remained in place throughout the season. In the treatment group, drone combs were removed on 16 June, 16 July, 16 August, and 16 September and replaced with empty drone combs (16 June) or with drone combs removed on the previous replacement date. In the early fall, the average mite-to-bee ratio in the control group was significantly greater than the corresponding ratio in the treatment group. Drone brood removal did not adversely affect colony health as measured by the size of the worker population or by honey production. Fall worker populations were similar in the two groups. Honey production in treatment colonies was greater than or similar to production in control colonies. These data demonstrate that drone brood removal can serve as a valuable component in an integrated pest management program for V. destructor and may reduce the need for other treatments on a colony-by-colony basis.

Mites associated with bark beetles and their hyperphoretic ophiostomatoid fungi

Treesearch

Richard W. Hofstetter; John Moser; Stacy Blomquist

2014-01-01

The role that mites play in many ecosystems is often overlooked or ignored. Within bark beetle habitats, more than 100 mite species exist and they have important impacts on community dynamics, ecosystem processes, and biodiversity of bark beetle systems. Mites use bark beetles to access and disperse among beetle-infested trees and the associations may range from...

Mechanisms of insecticide resistance in field populations of varroa mite (Acari: Mesostigmata: Varroidae)in Florida

USDA-ARS?s Scientific Manuscript database

The ectoparasitic mite Varroa destuctor is a serious threat to beekeeping and crops that rely on honey bee for pollination. The Varroa mite not only causes significant damage to honey bees by feeding on their haemolymph, but also serves as a vector of disease. In addition, the Varroa mite has develo...

A rapid method to assess grape rust mites on leaves and observations from case studies in western Oregon vineyards

USDA-ARS?s Scientific Manuscript database

A rapid method for extracting eriophyoid mites was adapted from previous studies to provide growers and IPM consultants with a practical, efficient, and reliable tool to monitor for rust mites in vineyards. The rinse in bag (RIB) method allows quick extraction of mites from collected plant parts (sh...

Hygienic Activity Toward Varroa Mites in Capped Brood is not Dependent on Mite Reproductive Status

USDA-ARS?s Scientific Manuscript database

- The varroa resistance of bees selectively bred for high levels of varroa sensitive hygiene (VSH) is characterized by a reduction of (1) the mite infestation rate (Harris 2007 J. Apic. Res. / Bee World 46: 134-139) and (2) the percentage of fertile mites (Harris and Harbo 1999 J. Econ. Entomol. 92:...

A method for rapidly marking adult varroa mites for use in brood inoculation experiments

USDA-ARS?s Scientific Manuscript database

We explored a method for marking varroa mites using correction fluid (PRESTO!TM Jumbo Correction Pen, Pentel Co., Ltd., Japan). Individual mites were placed on a piece of nylon mesh (165 mesh) to prevent the mites from moving during marking. A small piece of nylon fishing line (diameter = 0.30 mm)...

Scanning electron microscopy description of a new species of Demodex canis spp.

PubMed

Tamura, Y; Kawamura, Y; Inoue, I; Ishino, S

2001-10-01

Between 1997 and 1999, the prevalence of Demodex canis mites was determined in 150 dogs. In two dogs, we found two different species of mites; Demodex canis and another, unidentified, Demodex mite. The unidentified Demodex mite species had several different morphological features. First, it had a short opisthosoma and an obtuse end. In addition, the fourth coxisternal plate was rectangular and there was a band-like segmental plate between the fourth coxisternal plate and opisthosoma. Although all of the morphology and the development of male mites could not be investigated in this study, the location of the opisthosoma and the genital pore clearly differed from Demodex canis, suggesting that this unidentified mite is a new species.

Interactions between natural enemies: Effect of a predatory mite on transmission of the fungus Neozygites floridana in two-spotted spider mite populations.

PubMed

Trandem, Nina; Berdinesen, Ronny; Pell, Judith K; Klingen, Ingeborg

2016-02-01

Introducing the predatory mite Phytoseiulus persimilis into two-spotted spider mite, Tetranychus urticae, populations significantly increased the proportion of T. urticae infected with the spider mite pathogen Neozygites floridana in one of two experiments. By the final sampling occasion, the number of T. urticae in the treatment with both the predator and the pathogen had declined to zero in both experiments, while in the fungus-only treatment T. urticae populations still persisted (20-40 T. urticae/subsample). Releasing P. persimilis into crops in which N. floridana is naturally present has the potential to improve spider mite control more than through predation alone. Copyright © 2016 Elsevier Inc. All rights reserved.

Relative resistance or susceptibility of maple (Acer) species, hybrids and cultivars to six arthropod pests of production nurseries.

PubMed

Seagraves, Bonny L; Redmond, Carl T; Potter, Daniel A

2013-01-01

Maples (Acer spp.) in production nurseries are vulnerable to numerous arthropod pests that can stunt or even kill the young trees. Seventeen cultivars representing various Acer species and hybrids were evaluated for extent of infestation or injury by shoot and trunk borers (Proteoteras aesculana, Chrysobothris femorata), potato leafhopper (Empoasca fabae), Japanese beetle (Popillia japonica), maple spider mite (Oligonychus aceris) and calico scale (Eulecanium cerasorum). Evaluations were done in replicated field plots in central and western Kentucky. All of the maples were susceptible, to varying degrees, to one or more key pest(s). Red maples (A. rubrum) were relatively vulnerable to potato leafhopper injury and borers but nearly free of Japanese beetle feeding and spider mites. Sugar maples sustained conspicuous Japanese beetle damage but had very low mite populations, whereas the opposite was true for Freeman maples (A. × freemanii). A. campestre was heavily infested by calico scale. Within each species or hybrid there were cultivar differences in degree of infestation or damage by particular pests. The results should help growers to focus pest management efforts on those plantings at greatest risk from particular pests, and to choose cultivars requiring fewer insecticide inputs to produce a quality tree. Copyright © 2012 Society of Chemical Industry.

[Dynamics of infection of Fringilla coelebs chaffinch nestlings with feather mites (Acari: Analgoidea)].

PubMed

Mironov, S V; Malyshev, L L

2002-01-01

A process of infecting the chaffinch nestlings Fringilla coelebs with three analgoid feather mites, Analges passerinus L., 1758, Monojoubertia microphylla (Robin, 1877), and Pteronyssoides striatus (Robin, 1977), commonly occurred on this bird species was investigated. 15 nests contained totally 65 nestlings, from 2 to 6 individuals in a brood, have been examined from the day of hatching till 11th day. Observations were held in the neighbourhood of the bird banding station "Rybachy" (Russia, Kaliningrad Province) in June of 1982. Number of mites on alive nestlings taken temporarily from their nest was counted by means of binocular lens under the magnification x12.5 and x25. The nestlings receive the mites from the chaffinch female during the night time, when the female sits together with the young birds and heats them. In the condition of this prolonged direct contact the mites migrate from the female onto the nestlings. As it was shown in our study of seasonal dynamics of mites on the chaffinch (Mironov, 2000), the chaffinch female only gives its mites to young generation and looses about three quarter of its mite micropopulation during the nesting period (June), hile in the chaffinch males the number of mites continues to increase during all summer. The infections with three feather mite species happen in the second part of the nestling's stay in the nest. The starting time of this process, its intensity, and sex and age structure of mite micropopulations on the nestlings just before their leaving the nest are different in the mite species examined. These peculiarities of feather mite species are determined by the biology of examined species, and first of all by their morphological characteristic and specialisation to different microhabitats, i.e. certain structural zones of plumage. Pteronyssoides striatus (Pteronyssidae) is rather typical mite specialised to feathers with vanes. In adult birds with completely developed plumage this species occupies the ventral surface of the big upper coverts of primary flight feathers. This species appears on the chaffinch nestlings in a significant number on 7th day. The mites occupy the basal parts of primary flight feathers represented in that moment by the rods only. They sit on practically open and smooth surface of this microhabitat, which is uncommon for them, because the vanes of the big upper coverts are not yet open and also represented by thin rods. During the period of the last 5 days (from 7 to 11th day) the mean number of mites per one nestling increases from 2.3 +/- 0.5 to 17.1 +/- 1.8 mites. Just before the day, when the nestling leave the nest, the tritonymphs absolutely predominate (82.4%) in the micropopulation of P. striatus. Analges passerinus (Analgidae) is specialised to live in the friable layer formed by numerous not-engaged thread barbles of the down feathers and basal parts of the body covert feathers. Mites have special hooks on legs used for hard attaching to the barbles and for fast moving in the friable layer of feathers. On the chaffinch nestlings, these mites appear usually on 8th day, when the rod-like body covert feathers begin to open on apices and form short brushes; however some individuals occur on the skin of nestlings even on 6th day. The mean number of mites per nestling on the 11th day reaches 16.5 +/- 1.4 individuals. The micropopulation of A. passerinus is represented on the nestlings mainly by the females (45.5%), tritonymphs (23.6%) and males (11.5%). Monojobertia microphylla (Proctophyllodidae) is a typical dweller of feathers with large vanes. Mites of this species commonly occupy the ventral surface of primary and secondary flight feathers and also respective big upper covert feathers of wings. M. microphylla appears on the nestlings in a significant number (7.1 +/- 1.2 mites) on 9th day, only when the primary flight feathers already have short vanes about 10 mm in length. In next three days the number of mites increases very fast and reaches on 11th day 60.3 +/- 5.7 mites per nestling. In the micropopulation of this species, the tritonymphs count 38.3%, and the quota of males and females is 25.3% each. The migration of this species goes most intensively, than in two other species. An analitic selection of logistic curves shows, that the increasing of mite number during the process of infection with three mite species may be most adequately described by the sigmoid curves with clearly recognizable levels of saturation, which can be theoretically reached. Indeed, the number of mite individuals being able to migrate onto the nestlings is limited by their number on a respective chaffinch female. In a contrast, the increasing of plumage indices, for instance the length of flight feathers, has almost linear character during the period of observation. The beginning of mite migration is determined by the development of respective microhabitats in the plumage of nestlings, or at least by the development of certain structure elements of plumage, where mites are able to attach for a while, before that moment, when the nestlings will develop the plumage completely and begin to fly. In three mite species examined, the process of infection was performed by older stages, namely by the imago and/or tritonymphs. This can be explained by two reasons. On the one hand, the older stages are most active in their movement, resistible and able to survive successfully on new host individuals. On the other hand, the older stage are ready for the reproduction or will be ready after one moulting. The older stages of mites can quickly create a large and self-supporting micropopulations on the birds, therefore this strategy ensures a successful subsequent existence of the parasite species. In cases, when mites (A. passerinus, M. microphylla) migrate into the respective microhabitats structurally corresponding to their normal microhabitats on adult birds, the micropopulations of these mite species include a significant or dominant quota of females and males. When the normal microhabitat is not yet formed, feather mites migrate into neighboring structure elements of plumage, where they can survive and wait for the development of normal microhabitat, to which they are well adapted. Therefore, in the case of P. striatus, its micropopulations on the chaffinch nestlings are represented mainly by the tritonymphs.

Comparison of Varroa destructor and Worker Honeybee Microbiota Within Hives Indicates Shared Bacteria.

PubMed

Hubert, Jan; Kamler, Martin; Nesvorna, Marta; Ledvinka, Ondrej; Kopecky, Jan; Erban, Tomas

2016-08-01

The ectoparasitic mite Varroa destructor is a major pest of the honeybee Apis mellifera. In a previous study, bacteria were found in the guts of mites collected from winter beehive debris and were identified using Sanger sequencing of their 16S rRNA genes. In this study, community comparison and diversity analyses were performed to examine the microbiota of honeybees and mites at the population level. The microbiota of the mites and honeybees in 26 colonies in seven apiaries in Czechia was studied. Between 10 and 50 Varroa females were collected from the bottom board, and 10 worker bees were removed from the peripheral comb of the same beehive. Both bees and mites were surface sterilized. Analysis of the 16S rRNA gene libraries revealed significant differences in the Varroa and honeybee microbiota. The Varroa microbiota was less diverse than was the honeybee microbiota, and the relative abundances of bacterial taxa in the mite and bee microbiota differed. The Varroa mites, but not the honeybees, were found to be inhabited by Diplorickettsia. The relative abundance of Arsenophonus, Morganella, Spiroplasma, Enterococcus, and Pseudomonas was higher in Varroa than in honeybees, and the Diplorickettsia symbiont detected in this study is specific to Varroa mites. The results demonstrated that there are shared bacteria between Varroa and honeybee populations but that these bacteria occur in different relative proportions in the honeybee and mite bacteriomes. These results support the suggestion of bacterial transfer via mites, although only some of the transferred bacteria may be harmful.

Down-regulation of plant defence in a resident spider mite species and its effect upon con- and heterospecifics.

PubMed

Godinho, Diogo P; Janssen, Arne; Dias, Teresa; Cruz, Cristina; Magalhães, Sara

2016-01-01

Herbivorous spider mites occurring on tomato plants (Solanum lycopersicum L.) cope with plant defences in various manners: the invasive Tetranychus evansi reduces defences below constitutive levels, whereas several strains of T. urticae induce such defences and others suppress them. In the Mediterranean region, these two species co-occur on tomato plants with T. ludeni, another closely related spider mite species. Unravelling how this third mite species affects plant defences is thus fundamental to understanding the outcome of herbivore interactions in this system. To test the effect of T. ludeni on tomato plant defences, we measured (1) the activity of proteinase inhibitors, indicating the induction of plant defences, in those plants, and (2) mite performance on plants previously infested with each mite species. We show that the performance of T. evansi and T. ludeni on plants previously infested with T. ludeni or T. evansi was better than on clean plants, indicating that these two mite species down-regulate plant defences. We also show that plants attacked by these mite species had lower activity of proteinase inhibitors than clean plants, whereas herbivory by T. urticae increased the activity of these proteins and resulted in reduced spider mite performance. This study thus shows that the property of down-regulation of plant defences below constitutive levels also occurs in T. ludeni.

Comparative performance of two mite-resistant stocks of honey bees (Hymenoptera: Apidae) in Alabama beekeeping operations.

PubMed

Ward, Kenneth; Danka, Robert; Ward, Rufina

2008-06-01

The utility of USDA-developed Russian and varroa sensitive hygiene (VSH) honey bees, Apis mellifera L. (Hymenoptera: Apidae), was compared with that of locally produced, commercial Italian bees during 2004-2006 in beekeeping operations in Alabama, USA. Infestations of varroa mites, Varroa destructor Anderson & Truman (Acari: Varroidae), were measured twice each year, and colonies that reached established economic treatment thresholds (one mite per 100 adult bees in late winter; 5-10 mites per 100 adult bees in late summer) were treated with acaricides. Infestations of tracheal mites, Acarapis woodi (Rennie) (Acari: Tarsonemidae), were measured autumn and compared with a treatment threshold of 20% mite prevalence. Honey production was measured in 2005 and 2006 for colonies that retained original test queens. Throughout the three seasons of measurement, resistant stocks required less treatment against parasitic mites than the Italian stock. The total percentages of colonies needing treatment against varroa mites were 12% of VSH, 24% of Russian, and 40% of Italian. The total percentages requiring treatment against tracheal mites were 1% of Russian, 8% of VSH and 12% of Italian. The average honey yield of Russian and VSH colonies was comparable with that of Italian colonies each year. Beekeepers did not report any significant behavioral problems with the resistant stocks. These stocks thus have good potential for use in nonmigratory beekeeping operations in the southeastern United States.

Driving factors of the communities of phytophagous and predatory mites in a physic nut plantation and spontaneous plants associated.

PubMed

Cruz, Wilton P; Sarmento, Renato A; Teodoro, Adenir V; Neto, Marçal P; Ignacio, Maíra

2013-08-01

Seasonal changes in climate and plant diversity are known to affect the population dynamics of both pests and natural enemies within agroecosystems. In Brazil, spontaneous plants are usually tolerated in small-scale physic nut plantations over the year, which in turn may mediate interactions between pests and natural enemies within this agroecosystem. Here, we aimed to access the influence of seasonal variation of abiotic (temperature, relative humidity and rainfall) and biotic (diversity of spontaneous plants, overall richness and density of mites) factors on the communities of phytophagous and predatory mites found in a physic nut plantation and its associated spontaneous plants. Mite sampling was monthly conducted in dicotyledonous and monocotyledonous leaves of spontaneous plants as well as in physic nut shrubs over an entire year. In the dry season there was a higher abundance of phytophagous mites (Tenuipalpidae, Tarsonemidae and Tetranychidae) on spontaneous plants than on physic nut shrubs, while predatory mites (Phytoseiidae) showed the opposite pattern. The overall density of mites on spontaneous plants increased with relative humidity and diversity of spontaneous plants. Rainfall was the variable that most influenced the density of mites inhabiting physic nut shrubs. Agroecosystems comprising spontaneous plants associated with crops harbour a rich mite community including species of different trophic levels which potentially benefit natural pest control due to increased diversity and abundance of natural enemies.

Association between HLA genes and dust mite sensitivity in a Brazilian population.

PubMed

da Costa Lima Caniatti, Marcela Caleffi; Borelli, Sueli Donizete; Guilherme, Ana Lúcia Falavigna; Tsuneto, Luiza Tamie

2017-02-01

Type I hypersensitivity, also known as IgE-mediated allergy, is a complex, multifactorial condition whose onset and severity are influenced by both genetic and environmental factors. Mite allergens stimulate the production of humoral response (IgE), especially in children, which is closely involved in atopic asthma and rhinitis. This study aimed to investigate the association between HLA class I (-A, -B, and -C), and HLA class II (-DRB1) genes in individuals sensitive to dust mites (Dermatophagoides farinae, Dermatophagoides pteronyssinus, or Blomia tropicalis) and mite-insensitive controls. 396 participants were grouped as mite-sensitive and mite-insensitive according to immediate hypersensitivity as determined by skin-prick tests, and to HLA genotyping by polymerase chain reaction-sequence specific oligonucleotide (PCR-SSO). After chi-square heterogeneity testing no significant differences were observed in HLA-A, B, and C genes, except for the HLA-DRB1 locus, which, showed a negative association for DRB1∗04, between mite-sensitive and mite-insensitive individuals. In high resolution, DRB1∗04:11 allele was significantly different from all other results (P=0.0042, OR=0.26, and 95%CI=0.09-0.70). The analysis stratified by etiologic agent confirmed these associations. Our results suggest a possible association between HLA-DRB1 genes and hypersensitivity to dust mites. Copyright © 2016 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Comparison of cultivars of ornamental crop Gerbera jamesonii on production of spider mite-induced volatiles, and their attractiveness to the predator Phytoseiulus persimilis.

PubMed

Krips, O E; Willems, P E; Gols, R; Posthumus, M A; Gort, G; Dicke, M

2001-07-01

We investigated whether volatiles produced by spider mite-damaged plants of four gerbera cultivars differ in attractiveness to Phytoseiulus persimilis, a specialist predator of spider mites, and how the mite-induced odor blends differ in chemical composition. The gerbera cultivars differed in resistance, as expressed in terms of spider mite intrinsic rate of population increase (rm). In order of increasing resistance these were Sirtaki, Rondena, Fame, and Bianca. To correct for differences in damage inflicted on the cultivars, we developed a method to compare the attractiveness of the blends, based on the assumption that a larger amount of spider mite damage leads to higher attraction of P persimilis. Spider mite-induced volatiles of cultivars Rondena and Bianca were preferred over those of cultivar Sirtaki. Spider mite-induced volatiles of cultivars Sirtaki and Fame did not differ in attractiveness to P. persimilis. Sirtaki plants had a lower relative production of terpenes than the other three cultivars. This was attributed to a low production of cis-alpha-bergamotene, trans-alpha-bergamotene, trans-beta-bergamotene, and (E)-beta-farnesene. The emission of (E)-beta-ocimene and linalool was lower in Sirtaki and Fame leaves than in Bianca and Rondena. The importance of these chemical differences in the differential attraction of predatory mites is discussed.

Remote sensing to detect the movement of wheat curl mites through the spatial spread of virus symptoms, and identification of thrips as predators of wheat curl mites

NASA Astrophysics Data System (ADS)

Stilwell, Abby R.

The wheat curl mite (WCM), Aceria tosichella Keifer, transmits three viruses to winter wheat: wheat streak mosaic virus, High Plains virus, and Triticum mosaic virus. This virus complex causes yellowing of the foliage and stunting of plants. WCMs disperse by wind, and an increased understanding of mite movement and subsequent virus spread is necessary in determining the risk of serious virus infections in winter wheat. These risk parameters will help growers make better decisions regarding WCM management. The objectives of this study were to evaluate the capabilities of remote sensing to identify virus infected plants and to establish the potential of using remote sensing to track virus spread and consequently, mite movement. Although the WCM is small and very hard to track, the viruses it vectors produce symptoms that can be detected with remote sensing. Field plots of simulated volunteer wheat were established between 2006 and 2009, infested with WCMs, and spread mites and virus into adjacent winter wheat. The virus gradients created by WCM movement allowed for the measurement of mite movement potential with both proximal and aerial remote sensing instruments. The ability to detect WCM-vectored viruses with remote sensing was investigated by comparing vegetation indices calculated from proximal remote sensing data to ground truth data obtained in the field. Of the ten vegetation indices tested, the red edge position (REP) index had the best relationship with ground truth data. The spatial spread of virus from WCM source plots was modeled with cokriging. Virus symptoms predicted by cokriging occurred in an oval pattern displaced to the southeast. Data from the spatial spread in small plots of this study were used to estimate the potential sphere of influence for volunteer wheat fields. The impact of thrips on WCM populations was investigated by a series of greenhouse, field, and observational studies. WCM populations in winter wheat increased more slowly when thrips populations were higher, both in the field and in the greenhouse. Two species of thrips, Thrips tabaci Lindeman and Frankliniella occidentalis (Pergande) were observed to feed directly on WCMs. The collective results from this study identify thrips as a regulating factor for WCM populations.

Comparison and Field Validation of Binomial Sampling Plans for Oligonychus perseae (Acari: Tetranychidae) on Hass Avocado in Southern California.

PubMed

Lara, Jesus R; Hoddle, Mark S

2015-08-01

Oligonychus perseae Tuttle, Baker, & Abatiello is a foliar pest of 'Hass' avocados [Persea americana Miller (Lauraceae)]. The recommended action threshold is 50-100 motile mites per leaf, but this count range and other ecological factors associated with O. perseae infestations limit the application of enumerative sampling plans in the field. Consequently, a comprehensive modeling approach was implemented to compare the practical application of various binomial sampling models for decision-making of O. perseae in California. An initial set of sequential binomial sampling models were developed using three mean-proportion modeling techniques (i.e., Taylor's power law, maximum likelihood, and an empirical model) in combination with two-leaf infestation tally thresholds of either one or two mites. Model performance was evaluated using a robust mite count database consisting of >20,000 Hass avocado leaves infested with varying densities of O. perseae and collected from multiple locations. Operating characteristic and average sample number results for sequential binomial models were used as the basis to develop and validate a standardized fixed-size binomial sampling model with guidelines on sample tree and leaf selection within blocks of avocado trees. This final validated model requires a leaf sampling cost of 30 leaves and takes into account the spatial dynamics of O. perseae to make reliable mite density classifications for a 50-mite action threshold. Recommendations for implementing this fixed-size binomial sampling plan to assess densities of O. perseae in commercial California avocado orchards are discussed. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The curse of the prey: Sarcoptes mite molecular analysis reveals potential prey-to-predator parasitic infestation in wild animals from Masai Mara, Kenya

PubMed Central

2011-01-01

Background Recently, there have been attempts to understand the molecular epidemiology of Sarcoptes scabiei, to evaluate the gene flow between isolates of S. scabiei from different hosts and geographic regions. However, to our knowledge, a molecular study has not been carried out to assess the molecular diversity and gene flow of Sarcoptes mite in a predator/prey ecosystem. Results Our study revealed an absence of gene flow between the two herbivore (Thomson's gazelle and wildebeest)- and between the two carnivore (lion and cheetah)-derived Sarcoptes populations from Masai Mara (Kenya), which is in discrepancy with the host-taxon law described for wild animals in Europe. Lion- and wildebeest-derived Sarcoptes mite populations were similar yet different from the Thomson's gazelle-derived Sarcoptes population. This could be attributed to Sarcoptes cross-infestation from wildebeest ("favourite prey") of the lion, but not from Thomson's gazelle. The cheetah-derived Sarcoptes population had different subpopulations: one is cheetah-private, one similar to the wildebeest- and lion-derived Sarcoptes populations, and another similar to the Thomson's gazelle-derived Sarcoptes mite population, where both wildebeest and Thomson's gazelle are "favourite preys" for the cheetah. Conclusions In a predator/prey ecosystem, like Masai Mara in Kenya, it seems that Sarcoptes infestation in wild animals is prey-to-predator-wise, depending on the predator's "favourite prey". More studies on the lion and cheetah diet and behaviour could be of great help to clarify the addressed hypotheses. This study could have further ramification in the epidemiological studies and the monitoring protocols of the neglected Sarcoptes mite in predator/prey ecosystems. PMID:21978557

Preventive efficacy of a topical combination of fipronil--(S)-methoprene--eprinomectin--praziquantel against ear mite (Otodectes cynotis) infestation of cats through a natural infestation model.

PubMed

Beugnet, Frédéric; Bouhsira, Emilie; Halos, Lénaïg; Franc, Michel

2014-01-01

A study based on naturally infested cats was designed to evaluate the effectiveness of a single treatment with a topical formulation containing fipronil, (S)-methoprene, eprinomectin and praziquantel, for the prevention of Otodectes cynotis infestation in cats. Six treated cats and six untreated cats were housed with three chronically Otodectes cynotis-infested cats, respectively. The cats of each group were kept together in a 20-m(2) room for 1 month. Both clinical examination and ear mite counts were conducted on Day 28. All donor cats were confirmed to be chronically infested with Otodectes cynotis on Day -1 and Day 28. From untreated control cats, 129 live mites were recovered on Day 28 and all cats were found to be infested. In the treated group, three cats were found to be infested, with a total of five live mites recovered, the difference between the two groups being significant (p = 0.003). One treatment corresponded to 96% preventive efficacy at Day 28 based on ear mite counts. With regard to cerumen, the clinical score increased significantly for untreated cats between Day -1 and Day 28 (p = 0.00026) and not for treated cats (p = 0.30). The difference in cerumen abundance was significant between untreated and treated cats on Day 28 (p = 0.0035). Concerning the pruritic reflex in at least one ear, all cats were negative at inclusion. All six untreated cats became positive and showed a reflex on Day 28, whereas no treated cat showed ear pruritus (p = 0.00026). © F. Beugnet et al., published by EDP Sciences, 2014.

Phoretic mites and their hyperphoretic fungi associated with flying Ips typographus japonicus Niijima (Col., Scolytidae) in Japan

Treesearch

J.C. Moser; T.J. Perry; K. Furuta

1997-01-01

Flying Ips typographus japonicus from Hokkaido (Japan) carried 12 species of phoretic mites, three of which were not previously recorded in Europe. The mite biologies were diverse, including specialists feeding on microorganisms, beetle eggs, and nematodes which were common under beetle elytra. Hyperphoretic on these mites were seven distinct species of fungal spores...

Population growth rate of dry bulb mite, Aceria tulipae (Keifer) (Acariformes: Eriophyidae) on agriculturally important plants and implications on taxonomic status

USDA-ARS?s Scientific Manuscript database

Dry bulb mite (DBM), Aceria tulipae, is an economically important mite with a worldwide distribution and a broad host range. As a generalist, it is the most important eriophyoid mite attacking bulbous plants such as garlic, onion, and tulip. To date, DBM has been recorded on host plants belonging to...

Honey Bee (Hymenoptera: Apidae) with the Trait of Varroa Sensitive Hygiene Remove Brood with All Reproductive Stages of Varroa Mites (Mesostigmata: Varroidae)

USDA-ARS?s Scientific Manuscript database

Varroa Sensitive Hygiene (VSH) is a trait of honey bees, Apis mellifera L., which supports resistance to Varroa destructor mites. VSH is the hygienic removal of mite-infested pupae from capped brood. Bees selectively bred for VSH produce colonies in which the fertility of mites decreases over time...

State-dependent and odour-mediated anemotactic responses of the predatory mite Phytoseiulus persimilis in a wind tunnel.

PubMed

Van Tilborg, Merijn; Sabelis, Maurice W; Roessingh, Peter

2004-01-01

Anemotaxis in the predatory mite Phytoseiulus persimilis (both well-fed and starved), has previously been studied on a wire grid under slight turbulent airflow conditions yielding weak, yet distinct, gradients in wind speed and odour concentration (Sabelis and Van der Weel 1993). Such conditions might have critically influenced the outcome of the study. We repeated these experiments, under laminar airflow conditions on a flat surface in a wind tunnel, thereby avoiding variation in wind speed and odour concentration. Treatments for starved and well-fed mites were (1) still-air without herbivore-induced plant volatiles (HIPV) (well-fed mites only), (2) an HIPV-free air stream, and (3) an air stream with HIPV (originating from Lima bean plants infested by two-spotted spider mites, Tetranychus urticae). Well-fed mites oriented in random directions in still-air without HIPV. In an air stream, starved mites always oriented upwind, whether plant odours were present or not. Well-fed mites oriented downwind in an HIPV-free air stream, but in random directions in an air stream with HIPV. Only under the last treatment our results differed from those of Sabelis and Van der Weel (1993).

Stored product mites (Acari: Astigmata) infesting food in various types of packaging.

PubMed

Hubert, Jan; Nesvorna, Marta; Volek, Vlado

2015-02-01

From 2008 to 2014, stored product mites have been reported from prepackaged dried food on the market in the Czech Republic. The infestation was by Carpoglyphus lactis (L.) in dried fruits and Tyrophagus putrescentiae (Schrank) in dog feed. The infestation is presumably caused by poor protection of the packages. We compared various packaging methods for their resistance to mites using dried apricots and dog feed in laboratory experiments. The trial packages included nine different plastic films, monofilm, duplex and triplex, and one type of plastic cup (ten replicates per packaging type). All packaging materials are available on the Czech market for dried food products. The samples of dried food were professionally packed in a factory and packaged dried apricots were exposed to C. lactis and dog food to T. putrescentiae. After 3 months of exposure, the infestation and mite density of the prepackaged food was assessed. Mites were found to infest six types of packages. Of the packaging types with mites, 1-5 samples were infested and the maximum abundance was 1,900 mites g(-1) of dried food. Mites entered the prepackaged food by faulty sealing. Inadequate sealing is suggested to be the major cause of the emerged infestation of dried food.

The Allergen Der p3 from House Dust Mite Stimulates Store-Operated Ca2+ Channels and Mast Cell Migration through PAR4 Receptors.

PubMed

Lin, Yu-Ping; Nelson, Charmaine; Kramer, Holger; Parekh, Anant B

2018-04-19

The house dust mite is the principal source of perennial aeroallergens in man. How these allergens activate innate and adaptive immunity is unclear, and therefore, there are no therapies targeting mite allergens. Here, we show that house dust mite extract activates store-operated Ca 2+ channels, a common signaling module in numerous cell types in the lung. Activation of channel pore-forming Orai1 subunits by mite extract requires gating by STIM1 proteins. Although mite extract stimulates both protease-activated receptor type 2 (PAR2) and PAR4 receptors, Ca 2+ influx is more tightly coupled to the PAR4 pathway. We identify a major role for the serine protease allergen Der p3 in stimulating Orai1 channels and show that a therapy involving sub-maximal inhibition of both Der p3 and Orai1 channels suppresses mast cell activation to house dust mite. Our results reveal Der p3 as an important aeroallergen that activates Ca 2+ channels and suggest a therapeutic strategy for treating mite-induced asthma. Copyright © 2018 Elsevier Inc. All rights reserved.

[Mites in mattress dust and relevant environmental factors in student dormitories in Shenzhen].

PubMed

Wang, Bin; Wu, Jie; Liu, Zhi-gang; Ran, Pi-xin; Gao, Qiao; Luo, Chun-hui; Ai, Mei

2009-02-28

Three hundred and eight mattress dust samples were collected from college dormitories in Shenzhen with a mite prevalence of 88% (271/308). From the samples, 6163 mites were isolated and identified. Dermatophagoides farinae, D. pteronyssinus and Blomia tropicalis were three most abundant species, occupying 29.7%, 21.7% and 17.9%, respectively. It was found that sex of the students, mattress cover (bamboo mat or bed sheet), with or without air conditioner installation, and daily using of air conditioner (<2 h, 2-8 h and >8 h) had no significant influence on the mite prevalence (P>0.05). However, logistic regression analysis revealed that the risk of mite sensitization in male student dormitory was significantly lower than that in female dormitory (OR=0.55, P=0.038), and the risk of using bed sheets was significantly higher than using bamboo mats (OR=2.13, P=0.040). Both mite prevalence and the risk of mite sensitization significantly decreased with higher floor of the dormitory building.

House dust and forage mite allergens and their role in human and canine atopic dermatitis.

PubMed

Nuttall, T J; Hill, Peter B; Bensignor, E; Willemse, T

2006-08-01

This article reviews the literature regarding the role of house dust and forage mite allergens in canine atopic dermatitis. The presence of immunoglobulin E (IgE) to these mites, especially to Dermatophagoides farinae, is common in both normal and atopic dogs. Exposure of dogs to the different mites is described both in the direct environment and in the coat of animals for house dust mites and in the food for forage mites. Allergens causing allergic disease in dogs seem to be different from those in humans. Dogs seem to react to high molecular weight allergens, compared to the low molecular weight group 1 and group 2 proteases that are commonly implicated in humans with atopic diseases. Despite numerous published studies dealing with this subject, a number of questions still need to be addressed to better understand the exact role of these mites in the pathogenesis of canine atopic dermatitis and to improve the quality of the allergens used in practice.

Outbreak of tropical rat mite (Ornithonyssus bacoti) dermatitis in a home for disabled persons.

PubMed

Baumstark, J; Beck, W; Hofmann, H

2007-01-01

Five mentally handicapped individuals living in a home for disabled persons in Southern Germany were seen in our outpatient department with pruritic, red papules predominantly located in groups on the upper extremities, neck, upper trunk and face. Over several weeks 40 inhabitants and 5 caretakers were affected by the same rash. Inspection of their home and the sheds nearby disclosed infestation with rat populations and mites. Finally the diagnosis of tropical rat mite dermatitis was made by the identification of the arthropod Ornithonyssus bacoti or so-called tropical rat mite. The patients were treated with topical corticosteroids and antihistamines. After elimination of the rats and disinfection of the rooms by a professional exterminator no new cases of rat mite dermatitis occurred. The tropical rat mite is an external parasite occurring on rats, mice, gerbils, hamsters and various other small mammals. When the principal animal host is not available, human beings can become the victim of mite infestation. 2007 S. Karger AG, Basel

STUDY OF ACAROID MITES POLLUTION IN STORED FRUIT-DERIVED CHINESE MEDICINAL MATERIALS.

PubMed

Xu, Li-fa; Li, He-xia; Xu, Peng-fei; Xu, Hai-feng; Li, Chao-pin

2015-08-01

to investigate the species and breeding density of acaroid mites in stored fruit-derived Chinese medicinal materials in Anhui province. samples of stored fruit-derived Chinese medicinal materials were collected from 30 herb stores and storehouses in 17 Anhui cities, where the breeding acaroids mites were detected. 20 species of acaroids mites were found in 33 samples, belonging to 15 genus, 5 families of the acaridae respectively, among which T. putrescentiae, A. farinae, C. lactis, and C. berlesei are predominant species. stored fruit-derived Chinese medicinal materials in Anhui areas suffer from serious acaroid mites pollution. Therefore, proactive measures should be taken to control acaroid mites from breeding in an effort to reduce the harm on medicinal materials. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Population growth of Varroa destructor (Acari: Varroidae) in colonies of Russian and unselected honey bee (Hymenoptera: Apidae) stock as related to numbers of foragers with mites

USDA-ARS?s Scientific Manuscript database

Varroa mites are an external parasite of honey bees and a leading cause of colony losses worldwide. Varroa populations can be controlled with miticides, but mite resistant stocks such as the Russian honey bee (RHB) also are available. RHB and other mite resistant stock limit Varroa population growth...

Feather mite abundance varies but symbiotic nature of mite-host relationship does not differ between two ecologically dissimilar warblers

Treesearch

Alix E. Matthews; Jeffery L. Larkin; Douglas W. Raybuck; Morgan C. Slevin; Scott H. Stoleson; Than J. Boves

2017-01-01

Feather mites are obligatory ectosymbionts of birds that primarily feed on the oily secretions from the uropygial gland. Feather mite abundance varies within and among host species and has various effects on host condition and fitness, but there is little consensus on factors that drive variation of this symbiotic system. We tested hypotheses regarding how within-...

Predatory Mite Attraction to Herbivore-induced Plant Odors is not a Consequence of Attraction to Individual Herbivore-induced Plant Volatiles

PubMed Central

De Bruijn, Paulien J. A.; Sabelis, Maurice W.

2008-01-01

Predatory mites locate herbivorous mites, their prey, by the aid of herbivore-induced plant volatiles (HIPV). These HIPV differ with plant and/or herbivore species, and it is not well understood how predators cope with this variation. We hypothesized that predators are attracted to specific compounds in HIPV, and that they can identify these compounds in odor mixtures not previously experienced. To test this, we assessed the olfactory response of Phytoseiulus persimilis, a predatory mite that preys on the highly polyphagous herbivore Tetranychus urticae. The responses of the predatory mite to a dilution series of each of 30 structurally different compounds were tested. They mites responded to most of these compounds, but usually in an aversive way. Individual HIPV were no more attractive (or less repellent) than out-group compounds, i.e., volatiles not induced in plants fed upon by spider-mites. Only three samples were significantly attractive to the mites: octan-1-ol, not involved in indirect defense, and cis-3-hexen-1-ol and methyl salicylate, which are both induced by herbivory, but not specific for the herbivore that infests the plant. Attraction to individual compounds was low compared to the full HIPV blend from Lima bean. These results indicate that individual HIPV have no a priori meaning to the mites. Hence, there is no reason why they could profit from an ability to identify individual compounds in odor mixtures. Subsequent experiments confirmed that naive predatory mites do not prefer tomato HIPV, which included the attractive compound methyl salicylate, over the odor of an uninfested bean. However, upon associating each of these odors with food over a period of 15 min, both are preferred. The memory to this association wanes within 24 hr. We conclude that P. persimilis possesses a limited ability to identify individual spider mite-induced plant volatiles in odor mixtures. We suggest that predatory mites instead learn to respond to prey-associated mixtures of volatiles and, thus, to odor blends as a whole. PMID:18521678

Ophiostomatoid fungi associated with conifer-infesting beetles and their phoretic mites in Yunnan, China

PubMed Central

Chang, Runlei; Duong, Tuan A.; Taerum, Stephen J.; Wingfield, Michael J.; Zhou, Xudong; de Beer, Z. Wilhelm

2017-01-01

Abstract The Ophiostomatales is an Ascomycete order of fungi that accommodates several tree pathogens and many species that degrade wood. These fungi are commonly vectored by Scolytine bark and ambrosia beetles. In recent years it has also been shown that hyperphoretic mites on these beetles can vector some Ophiostomatales. Little is known regarding the Ophiostomatales in China and we have consequently explored the diversity of these fungi associated with conifer-infesting beetles and mites in Yunnan province. Galleries and beetles were collected for 17 beetle species, while 13 mite species were obtained from six of these beetle species. Collectively, 340 fungal isolates were obtained, 45 from beetles, 184 from mites, 56 from galleries and 55 isolates where the specific niche was not clear. DNA sequences for five gene regions (ITS, LSU, BT, EF, and CAL) were determined for fungal isolates representing different morphological groups. Phylogenetic analyses confirmed the presence of 19 fungal taxa, including five novel species described here as Ophiostoma acarorum sp. nov., Ophiostoma brevipilosi sp. nov., Graphilbum kesiyae sp. nov., Graphilbum puerense sp. nov., and Leptographium ningerense sp. nov. Ophiostoma ips was the most frequently isolated species, representing approximately 31% of all isolates. Six of 19 taxa were present on mites, beetles and in the galleries of the beetles, while three species were found on mites and galleries. Two species were found only on mites and one species only on a beetle. Although the numbers of beetles and mites were insufficient to provide statistical inferences, this study confirmed that mites are important vectors of the Ophiostomatales in China. We hypothesize that these mites are most likely responsible for horizontal transfer of fungal species between galleries of different beetle species. The fact that half of the fungal species found were new to science, suggests that the forests of east Asia include many undescribed Ophiostomatales yet to be discovered. PMID:29559821

The influence of Nosema (Microspora: Nosematidae) infection on honey bee (Hymenoptera: Apidae) defense against Varroa destructor (Mesostigmata: Varroidae).

PubMed

Bahreini, Rassol; Currie, Robert W

2015-11-01

The objectives of this study were to quantify the costs and benefits of co-parasitism with Varroa (Varroa destructor Anderson and Trueman) and Nosema (Nosema ceranae Fries and Nosema apis Zander) on honey bees (Apis mellifera L.) with different defense levels. Newly-emerged worker bees from either high-mite-mortality-rate (high-MMR) bees or low-mite-mortality-rate (low-MMR) bees were confined in forty bioassay cages which were either inoculated with Nosema spores [Nosema (+) group] or were left un-inoculated [Nosema (-) group]. Caged-bees were then inoculated with Varroa mites [Varroa (+) group] or were left untreated [Varroa (-) group]. This established four treatment combinations within each Nosema treatment group: (1) low-MMR Varroa (-), (2) high-MMR Varroa (-), (3) low-MMR Varroa (+) and (4) high-MMR Varroa (+), each with five replicates. Overall mite mortality in high-MMR bees (0.12±0.02 mites per day) was significantly greater than in the low-MMR bees (0.06±0.02 mites per day). In the Nosema (-) groups bee mortality was greater in high-MMR bees than low-MMR bees but only when bees had a higher mite burden. Overall, high-MMR bees in the Nosema (-) group showed greater reductions in mean abundance of mites over time compared with low-MMR bees, when inoculated with additional mites. However, high-MMR bees could not reduce mite load as well as in the Nosema (-) group when fed with Nosema spores. Mean abundance of Nosema spores in live bees and dead bees of both strains of bees was significantly greater in the Nosema (+) group. Molecular analyses confirmed the presence of both Nosema species in inoculated bees but N. ceranae was more abundant than N. apis and unlike N. apis increased over the course of the experiment. Collectively, this study showed differential mite mortality rates among different genotypes of bees, however, Nosema infection restrained Varroa removal success in high-MMR bees. Copyright © 2015 Elsevier Inc. All rights reserved.

CLIMATE CONDITIONS AFFECTING THE WITHIN-PLANT SPREAD OF BROAD MITES ON AZALEA.

PubMed

Mechant, E; Pauwels, E; Gobin, B

2014-01-01

The broad mite Polyphagotarsonemus latus (Banks) is considered a major pest in potted azalea, Flanders' flagship ornamental crop of Rhododendron simsii hybrids. In addition to severe economic damage, the broad mite is dreaded for its increasing resistance to acaricides. Due to restrictions in the use of broad spectrum acaricides, Belgian azalea growers are left with only three compounds, belonging to two mode of action groups and restricted in their number of applications, for broad mite control: abamectin, milbemectin and pyrethrin. Although P. latus can be controlled with predatory mites, the high cost of this system makes it (not yet) feasible for integration into standard azalea pest management systems. Hence, a maximum efficacy of treatments with available compounds is essential. Because abamectin, milbemectin and pyrethrin are contact acaricides with limited trans laminar flow, only broad mites located on shoot tips of azalea plants will be controlled after spraying. Consequently, the efficacy of chemical treatments is influenced by the location and spread of P. latus on the plant. Unfortunately, little is known on broad mites' within-plant spread or how it is affected by climatic conditions like temperature and relative humidity. Therefore, experiments were set up to verify whether climate conditions have an effect on the location and migration of broad mites on azalea. Broad mite infected azalea plants were placed in standard growth chambers under different temperature (T:2.5-25°C) and relative humidity (RH:55-80%) treatments. Within-plant spread was determined by counting mites on the shoot tips and inner leaves of azalea plants. Results indicate that temperature and relative humidity have no significant effect on the within-plant spread of P. latus. To formulate recommendations for optimal spray conditions to maximize the efficacy of broad mite control with acaricides, further experiments on the effect of light intensity and rain are scheduled.

An updated distribution and hosts: trombiculid mites (Acari: Trombidiformes) associated with small mammals in Yunnan Province, southwest China.

PubMed

Peng, Pei-Ying; Guo, Xian-Guo; Ren, Tian-Guang; Dong, Wen-Ge; Song, Wen-Yu

2016-05-01

Trombiculid mites (or chigger mites) are a large group of arthropods, and some of these species are vectors of Orientia tsutsugamushi, the causative agent of tsutsugamushi disease (scrub typhus). Yunnan Province is situated in the southwest of China, and its complicated topography, special altitude gradients, and high biodiversity have aroused the interest of many scientists to study the fauna and species diversity of plants and animals. To replenish our former faunal study, this paper listed all the scientific names of trombiculid mites in Yunnan Province, together with their hosts and collection sites (geographical distribution). A total of 120,138 individuals of trombiculid mites were collected from the body surface of 13,760 small mammal hosts (89.06 % of them are rodents) in 29 collection sites (counties) of Yunnan Province from 2001 to 2013. The 120,138 mites were identified as comprising 2 families (Trombiculidae and Leeuwenhoekiidae), 26 genera, and 274 species. The genus Leptotrombidium had the most abundant species (109 species) of 26 genera. Of the six main vectors of scrub typhus in China, five of them were found in Yunnan. Of the 274 chigger mite species, 23 were determined as the newly recorded species (new records), which were found in Yunnan Province for the first time. The identified 274 species of trombiculid mites in the present paper are much more than those from other provinces in China and even largely exceeded the species of trombiculid mites recorded from some other regions and countries in the world. Based on the formula of Chao 1, the total number of chigger mite species in Yunnan was approximately estimated to be 346 species, and about 72 species might have been missed in our sampling process.

Removal of drone brood from Apis mellifera (Hymenoptera: Apidae) colonies to control Varroa destructor (Acari: Varroidae) and retain adult drones.

PubMed

Wantuch, Holly A; Tarpy, David R

2009-12-01

The parasitic mite Varroa destructor Anderson & Trueman (Acari: Varroidae) has plagued European honey bees, Apis mellifera L. (Hymenoptera: Apidae), in the Americas since its introduction in the 1980s. For many years, these mites were sufficiently controlled using synthetic acaricides. Recently, however, beekeepers have experienced increased resistance by mites to chemical pesticides, which are also known to leave residues in hive products such as wax and honey. Thus there has been increased emphasis on nonchemical integrated pest management control tactics for Varroa. Because mites preferentially reproduce in drone brood (pupal males), we developed a treatment strategy focusing on salvaging parasitized drones while removing mites from them. We removed drone brood from colonies in which there was no acaricidal application and banked them in separate "drone-brood receiving" colonies treated with pesticides to kill mites emerging with drones. We tested 20 colonies divided into three groups: 1) negative control (no mite treatment), 2) positive control (treatment with acaricides), and 3) drone-brood removal and placement into drone-brood receiving colonies. We found that drone-brood trapping significantly lowered mite numbers during the early months of the season, eliminating the need for additional control measures in the spring. However, mite levels in the drone-brood removal group increased later in the summer, suggesting that this benefit does not persist throughout the entire season. Our results suggest that this method of drone-brood trapping can be used as an element of an integrated control strategy to control varroa mites, eliminating a large portion of the Varroa population with limited chemical treatments while retaining the benefits of maintaining adult drones in the population.

Tri-trophic level impact of host plant linamarin and lotaustralin on Tetranychus urticae and its predator Phytoseiulus persimilis.

PubMed

Rojas, M Guadalupe; Morales-Ramos, Juan Alfredo

2010-12-01

The impact of linamarin and lotaustralin content in the leaves of lima beans, Phaseolus lunatus L., on the second and third trophic levels was studied in the two-spotted spider mite, Tetranychus urticae (Koch), and its predator Phytoseiulus persimilis Athias-Henriot. The content of linamarin was higher in terminal trifoliate leaves (435.5 ppm) than in primary leaves (142.1 ppm) of Henderson bush lima beans. However, linamarin concentrations were reversed at the second trophic level showing higher concentrations in spider mites feeding on primary leaves (429.8 ppm) than those feeding on terminal trifoliate leaves (298.2 ppm). Concentrations of linamarin in the predatory mites were 18.4 and 71.9 ppm when feeding on spider mites grown on primary and terminal leaves, respectively. The concentration of lotaustralin in primary lima bean leaves was 103.12 ppm, and in spider mites feeding on these leaves was 175.0 ppm. Lotaustralin was absent in lima bean terminal trifoliate leaves and in mites feeding on these leaves. Fecundity of spider mites feeding on lima bean leaves (primary or trifoliate) was not significantly different from mites feeding on red bean, Phaseolus vulgaris L., primary leaves. However, the progeny sex ratio (in females per male) of spider mites feeding on lima bean leaves was significantly lower than progeny of spider mites feeding on red bean leaves (control). Fecundity and progeny sex ratio of P. persimilis were both significantly affected by the concentration of linamarin present in the prey. Changes in concentration of linamarin in living tissue across the three trophic levels are discussed.

Interactions in a tritrophic acarine predator-prey metapopulation system V: within-plant dynamics of Phytoseiulus persimilis and Tetranychus urticae (Acari: Phytoseiidae, Tetranychidae).

PubMed

Nachman, Gösta; Zemek, Rostislav

2003-01-01

To investigate the relative contributions of bottom-up (plant condition) and top-down (predatory mites) factors on the dynamics of the two-spotted spider mite (Tetranychus urticae), a series of experiments were conducted in which spider mites and predatory mites were released on bean plants. Plants inoculated with 2, 4, 8, 16, and 32 adult female T. urticae were either left untreated or were inoculated with 3 or 5 adult female predators (Phytoseiulus persimilis) one week after the introduction of spider mites. Plant area, densities of T. urticae and P. persimilis, and plant injury were assessed by weekly sampling. Data were analysed by a combination of statistical methods and a tri-trophic mechanistic simulation model partly parameterised from the current experiments and partly from previous data. The results showed a clear effect of predators on the density of spider mites and on the plant injury they cause. Plant injury increased with the initial number of spider mites and decreased with the initial number of predators. Extinction of T. urticae, followed by extinction of P. persimilis, was the most likely outcome for most initial combinations of prey and predators. Eggs constituted a relatively smaller part of the prey population as plant injury increased and of the predator population as prey density decreased. We did not find statistical evidence of P. persimilis having preference for feeding on T. urticae eggs. The simulation model demonstrated that bottom-up and top-down factors interact synergistically to reduce the density of spider mites. This may have important implications for biological control of spider mites by means of predatory mites.

Exceptionally High Levels of Genetic Diversity in Wheat Curl Mite (Acari: Eriophyidae) Populations from Turkey.

PubMed

Szydło, W; Hein, G; Denizhan, E; Skoracka, A

2015-08-01

Recent research on the wheat curl mite species complex has revealed extensive genetic diversity that has distinguished several genetic lineages infesting bread wheat (Triticum aestivum L.) and other cereals worldwide. Turkey is the historical region of wheat and barley (Hordeum vulgare L.) domestication and diversification. The close relationship between these grasses and the wheat curl mite provoked the question of the genetic diversity of the wheat curl mite in this region. The scope of the study was to investigate genetic differentiation within the wheat curl mite species complex on grasses in Turkey. Twenty-one wheat curl mite populations from 16 grass species from nine genera (Agropyron sp., Aegilops sp., Bromus sp., Elymus sp., Eremopyrum sp., Hordeum sp., Poa sp., Secale sp., and Triticum sp.) were sampled in eastern and southeastern Turkey for genetic analyses. Two molecular markers were amplified: the cytochrome oxidase subunit I coding region of mtDNA (COI) and the D2 region of 28S rDNA. Phylogenetic analyses revealed high genetic variation of the wheat curl mite in Turkey, primarily on Bromus and Hordeum spp., and exceptionally high diversity of populations associated with bread wheat. Three wheat-infesting wheat curl mite lineages known to occur on other continents of the world, including North and South America, Australia and Europe, were found in Turkey, and at least two new genetic lineages were discovered. These regions of Turkey exhibit rich wheat curl mite diversity on native grass species. The possible implications for further studies on the wheat curl mite are discussed. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Short form of Demodex species mite in the dog: occurrence and measurements.

PubMed

Chesney, C J

1999-02-01

A form of Demodex species mite shorter in length than Demodex canis was found in six consecutive cases of canine demodicosis. The mean length of the parasite was 122.6 microns (SD 12.0 microns, 39 mites counted), significantly shorter than either male or female forms of D canis (P < 0.0001). The proportion of short to long mites in each case varied from 0.5 to 22 per 100. In young dogs, skin signs associated with the presence of mites were first noted after about seven months, while in the oldest subject the disease became apparent at 10 years of age. This form of mite has now been found in four countries over three continents, the findings suggesting that it is not uncommon and is acquired in puppyhood, although it may be carried unnoticed for many years.

House dust mites on skin, clothes, and bedding of atopic dermatitis patients.

PubMed

Teplitsky, Valery; Mumcuoglu, Kosta Y; Babai, Ilan; Dalal, Ilan; Cohen, Rifka; Tanay, Amir

2008-08-01

Atopic dermatitis is a common allergic condition in children, often associated with a positive skin reaction to house dust mite allergens. To determine the presence of house dust mites on the skin, clothes, and bedding of patients with atopic dermatitis. Nineteen patients with atopic dermatitis were examined during a 2-year period. Samples from affected and healthy skin surfaces were obtained with adhesive tape, and dust samples from bedding and clothes were collected with a vacuum cleaner at the start of the study and 3-6 weeks later, and examined for the presence of house dust mites. The findings were compared with those of 21 healthy controls. The most common mite species on skin were Dermatophagoides pteronyssinus and Dermatophagoides farinae, which were found in nine patients and three controls. The patient group showed a significantly larger percentage of samples with mites than did the control group (34.9% and 7.9%, respectively) (P < 0.001), and a significantly larger percentage of individuals with at least one positive sample (84.2% and 14.2%, respectively) (P < 0.0001). No correlation was found between the number of mites on the skin and clothes/bedding of patients, or between patients and controls with regard to the number of mites on the clothes and bedding. Patients with atopic dermatitis showed a higher prevalence of mites on their skin than did healthy individuals, which could be involved in allergic sensitization and disease exacerbation.

PCR amplification and DNA sequencing of Demodex injai from otic secretions of a dog.

PubMed

Milosevic, Milivoj A; Frank, Linda A; Brahmbhatt, Rupal A; Kania, Stephen A

2013-04-01

The identification of Demodex mites from dogs is usually based on morphology and location. Mites with uncharacteristic features or from unusual locations, hosts or disease manifestations could represent new species not previously described; however, this is difficult to determine based on morphology alone. The goal of this study was to identify and confirm Demodex injai in association with otitis externa in a dog using PCR amplification and DNA sequencing. Otic samples were obtained from a beagle in which a long-bodied Demodex mite was identified. For comparison, Demodex mite samples were collected from a swab and scraping of the dorsal skin of a wire-haired fox terrier and an otic sample from a dog with generalized and otic demodicosis. To identify the Demodex mite, DNA was extracted, and 16S rRNA was amplified by PCR, sequenced and compared with Demodex sequences available in public databases and from separate samples morphologically diagnosed as D. injai and Demodex canis. PCR amplification of the long-bodied mite rRNA DNA obtained from otic samples was approximately 330 bp and was identical to that from the mite morphologically identified as D. injai obtained from the dorsal skin of a dog. Furthermore, the examined mite did not have any significant homology to any of the reported genes from Demodex spp. These results confirmed that the demodex mites in this case were D. injai. © 2013 The Authors. Veterinary Dermatology © 2013 ESVD and ACVD.

Immunogene and viral transcript dynamics during parasitic Varroa destructor mite infection of developing honey bee (Apis mellifera) pupae.

PubMed

Kuster, Ryan D; Boncristiani, Humberto F; Rueppell, Olav

2014-05-15

The ectoparasitic Varroa destructor mite is a major contributor to the ongoing honey bee health crisis. Varroa interacts with honey bee viruses, exacerbating their pathogenicity. In addition to vectoring viruses, immunosuppression of the developing honey bee hosts by Varroa has been proposed to explain the synergy between viruses and mites. However, the evidence for honey bee immune suppression by V. destructor is contentious. We systematically studied the quantitative effects of experimentally introduced V. destructor mites on immune gene expression at five specific time points during the development of the honey bee hosts. Mites reproduced normally and were associated with increased titers of deformed wing virus in the developing bees. Our data on different immune genes show little evidence for immunosuppression of honey bees by V. destructor. Experimental wounding of developing bees increases relative immune gene expression and deformed wing virus titers. Combined, these results suggest that mite feeding activity itself and not immunosuppression may contribute to the synergy between viruses and mites. However, our results also suggest that increased expression of honey bee immune genes decreases mite reproductive success, which may be explored to enhance mite control strategies. Finally, our expression data for multiple immune genes across developmental time and different experimental treatments indicates co-regulation of several of these genes and thus improves our understanding of the understudied honey bee immune system. © 2014. Published by The Company of Biologists Ltd.

Toxicity of bifenazate and its principal active metabolite, diazene, to Tetranychus urticae and Panonychus citri and their relative toxicity to the predaceous mites, Phytoseiulus persimilis and Neoseiulus californicus.

PubMed

Ochiai, Noriaki; Mizuno, Masayuki; Mimori, Norihiko; Miyake, Toshihiko; Dekeyser, Mark; Canlas, Liza Jara; Takeda, Makio

2007-01-01

Bifenazate is a novel carbazate acaricide discovered by Uniroyal Chemical (now Chemtura Corporation) for the control of phytophagous mites infesting agricultural and ornamental crops. Its acaricidal activity and that of its principal active metabolite, diazene, were characterized. Bifenazate and diazene had high toxicity and specificity both orally and topically to all life stages of Tetranychus urticae and Panonychus citri. Acute poisoning was observed with no temperature dependency. No cross-resistance was found to mites resistant to several other classes of acaricides, such as tebufenpyrad, etoxazole, fenbutatin oxide and dicofol. Bifenazate remained effective for a long time with only about a 10% loss of efficacy on T. urticae after 1 month of application in the field. All stages of development of the predatory mites, Phytoseiulus persimilis and Neoseiulus californicus, survived treatment by both bifenazate and diazene. When adult females of the two predatory mite species were treated with either bifenazate or diazene, they showed a normal level of fecundity and predatory activity in the laboratory, effectively suppressing spider mite population growth. Even when the predators were fed spider mite eggs that had been treated previously with bifenazate, they survived. These findings indicate that bifenazate is a very useful acaricide giving high efficacy, long-lasting activity and excellent selectivity for spider mites. It is, therefore, concluded that bifenazate is an ideal compound for controlling these pest mites.

House Dust Mite Prevalence in the House of Patients with Atopic Dermatitis in Mashhad, Iran.

PubMed

Ziyaei, Toktam; Berenji, Fariba; Jabbari-Azad, Farahzad; Fata, Abdolmajid; Jarahi, Lida; Fereidouni, Mohammad

2017-06-01

Being exposed to house dust mites intensifies atopic dermatitis. This study has investigated the contamination rate with Dermatophagoides mites in patient's residential home with atopic dermatitis. In this cross-sectional study, 40 patients took part with atopic dermatitis (positive or negative for mites by prick Dermal Test). Samples were collected from 3 locations (living room, bedroom and bed) by vacuum cleaner. Dust samples (transferred to freezer -20 °C) were examined by direct method and flotation. The data were analyzed using statistical SPSS vr.20 software. Twenty patients of positive prick test included 8 (40%) male and 12 (60%) female. The results of direct observation of mites: 7 cases (35%) in bedding sheets, 6 cases (30%) bedrooms' carpet, 3 cases (15%) living room's carpet. Twenty patients of negative prick test included 8 (40%) male and 12 (60%) female. Only mites were found (5%) in living room's carpets of negative prick test patients. Dermatophagoides pteronyssinus was more frequent than Dermatophagoides farina e. (98% vs 83%). Fifty-five percent of residential homes of prick test positive patients and only 5% of residential homes of prick test negative patients were positive for mite. Sunshine provided home had fewer mites than home where sunshine is not provided. Prick test positive patients used handmade carpets more than machine made ones. In positive prick test patients, mites were found in bed sheet and bedroom's carpet more than negative prick test patient's sheets and carpets.

Anti-mite measurements in mite-sensitive adult asthma. A controlled trial.

PubMed

Burr, M L; St Leger, A S; Neale, E

1976-02-14

A cross-over controlled trial has been conducted among 32 adult patients with mite-sensitive asthma. The bedclothes and pillows of each subject were laundered and vacuum-cleaned and a plastic cover applied to the mattress for six weeks in an attempt to reduce exposure to mites. No improvement in daily peak-flow reading or drug usage was found in comparison with a control period.

Behavioural responses of two-spotted spider mites induced by predator-borne and prey-borne cues.

PubMed

Gyuris, Enikő; Szép, Erna; Kontschán, Jenő; Hettyey, Attila; Tóth, Zoltán

2017-11-01

Applying predatory mites as biological control agents is a well established method against spider mites which are major pests worldwide. Although antipredator responses can influence the outcome of predator-prey interactions, we have limited information about what cues spider mites use to adjust their behavioural antipredator responses. We experimentally exposed two-spotted spider mites (Tetranychus urticae) to different predator-borne cues (using a specialist predator, Phytoseiulus persimilis, or a generalist predator, Amblyseius swirskii), conspecific prey-borne cues, or both, and measured locomotion and egg-laying activity. The reactions to predator species compared to each other manifested in reversed tendencies: spider mites increased their locomotion activity in the presence of P. persimilis, whereas they decreased it when exposed to A. swirskii. The strongest response was triggered by the presence of a killed conspecific: focal spider mites decreased their locomotion activity compared to the control group. Oviposition activity was not affected by either treatment. Our results point out that spider mites may change their behaviour in response to predators, and also to the presence of killed conspecifics, but these effects were not enhanced when both types of cues were present. The effect of social contacts among prey conspecifics on predator-induced behavioural defences is discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Patterns of infestation by the trombiculid mite Eutrombicula alfreddugesi in four sympatric lizard species (genus Tropidurus) in northeastern Brazil.

PubMed

Rocha, C F D; Cunha-Barros, M; Menezes, V A; Fontes, A f; Vrcibradic, D; Van Sluys, M

2008-06-01

We studied the parasitism by the chigger mite Eutrombicula alfreddugesi on four sympatric lizard species of the genus Tropidurus in Morro do Chapéu, Bahia state, Brazil: T. hispidus, T. cocorobensis, T. semitaeniatus and T. erythrocephalus. For each species, we investigated the patterns of infestation and analyzed to which extent they varied among the hosts. We calculated the spatial niche breadth of the chigger mite on the body of each host species and the distribution of mites along the hosts' bodies for each Tropidurus species. All four species of Tropidurus at Morro do Chapéu were parasited by the chigger mite, with high (97-100%) prevalences. Host body size significantly explained the intensity of mite infestation for all species, except T. erythrocephalus. The body regions with highest intensity of infestation in the four lizard species were the mite pockets. The spacial niche width of the chigger varied consistently among the four lizards species studied being highest for T. erytrocephalus and lowest for T. cocorobensis. We conclude that the distribution and intensity with which lizards of the genus Tropidurus are infested by Eutrombicula alfreddugesi larvae results from the interaction between aspects of host morphology (such as body size and the occurrence and distribution of mite pockets) and ecology (especially microhabitat use).

Correlation between the proportion of stained eggs and the number of mites (Dermanyssus gallinae) monitored using a 'non-parallel board trap'.

PubMed

Odaka, Makiko; Ogino, Kazumasa; Shikada, Michitaka; Asada, Kenichi; Kasa, Syoujirou; Inoue, Takahiro; Maeda, Ken

2017-12-01

The poultry red mite (Dermanyssus gallinae) is a serious problem for the poultry industry worldwide. However, the relationship between the mite population and the damage that they cause is still unclear. In this study, the mite population in poultry houses was examined using an established trap method, and the risk of blood-stained eggs caused by the mites was assessed. Traps were placed once a week outside the egg channels and/or on the floor in two poultry farms in Fukuoka Prefecture, Japan, from April 2012 to July 2014. The numbers of blood-stained eggs and total eggs were counted at weekly intervals. The results showed that the number of mites increased from April to May, and reached a peak around the beginning of June when the average temperature and humidity were >24°C and 70-90%, respectively. In the segmented model, the correlation between the proportion of blood-stained eggs and the number of mites or temperature was positive over a threshold. In conclusion, our established trap method is useful for monitoring mites and can be used to predict when poultry farms should be treated to prevent appearance of blood-stained eggs. © 2017 Japanese Society of Animal Science.

Identification of spider-mite species and their endosymbionts using multiplex PCR.

PubMed

Zélé, Flore; Weill, Mylène; Magalhães, Sara

2018-02-01

Spider mites of the genus Tetranychidae are severe crop pests. In the Mediterranean a few species coexist, but they are difficult to identify based on morphological characters. Additionally, spider mites often harbour several species of endosymbiotic bacteria, which may affect the biology of their hosts. Here, we propose novel, cost-effective, multiplex diagnostic methods allowing a quick identification of spider-mite species as well as of the endosymbionts they carry. First, we developed, and successfully multiplexed in a single PCR, primers to identify Tetranychus urticae, T. evansi and T. ludeni, some of the most common tetranychids found in southwest Europe. Moreover, we demonstrated that this method allows detecting multiple species in a single pool, even at low frequencies (up to 1/100), and can be used on entire mites without DNA extraction. Second, we developed another set of primers to detect spider-mite endosymbionts, namely Wolbachia, Cardinium and Rickettsia in a multiplex PCR, along with a generalist spider-mite primer to control for potential failure of DNA amplification in each PCR. Overall, our method represents a simple, cost-effective and reliable method to identify spider-mite species and their symbionts in natural field populations, as well as to detect contaminations in laboratory rearings. This method may easily be extended to other species.

The role of water temperature and laundry procedures in reducing house dust mite populations and allergen content of bedding.

PubMed

McDonald, L G; Tovey, E

1992-10-01

The effects of various laundry procedures on house dust mites and their allergens have been established. All mites were killed by water temperatures 55 degrees C or greater. Killing at lower temperatures was not enhanced by any of the pure detergents or laundry products tested. A cold cycle of laundry washing with or without laundry powder did not remove most live mites from bedding, however, the allergen concentration (Der p I/gm fine dust) was reduced by more than 90%. Dry cleaning did not reduce the allergen concentration of the dust, although most, if not all, mites were killed.

[Animal mites transmissible to humans and associated zoonosis].

PubMed

Jofré M, Leonor; Noemí H, Isabel; Neira O, Patricia; Saavedra U, Tirza; Díaz L, Cecilia

2009-06-01

Mites that affect animals (acariasis) can occasionally be transmitted to humans by incidental contact producing pruritus and dermatitis. Animals such as dogs, cats, mice, birds and reptiles, harbour several mite species. Hemophage mites and those that feed on lymph have the potential of transmitting important zoonotic agents (cuales??). The presence of lesions of unclear origin and a history of contact with pets or wild animals should alert towards the possibility of acariasis. Diagnosis is based on direct visualization of the mite,analysis of its morphology and obtaining information on the animal host. Awareness of these acarosis and the responsible care of pets and animals are the most relevant preventive measures.

Ectoparasitic mite and fungus on Harmonia axyridis

USDA-ARS?s Scientific Manuscript database

Ectoparasitic mites (Acarina: Podapolipidae) and ectoparasitic fungi (Laboulbeniales: Laboulbeniaceae) occur on ladybirds (Coleoptera: Coccinellidae) throughout the world (Riddick et al., 2009). This study documents the interaction of a coccinellid-specific mite Coccipolipus hippodamiae (McDaniel &...

Efficacy of 65% permethrin applied as a topical spot-on against walking dandruff caused by the mite, Cheyletiella yasguri in dogs.

PubMed

Endris, R G; Reuter, V E; Nelson, J D; Nelson, J A

2000-01-01

The efficacy of a 65% permethrin topically applied spot-on formulation (Defend EXspot Topical Remedy for Dogs, Schering-Plough Animal Health, Union, NJ) was determined against the dog mite, Cheyletiella yasguri (Smiley, 1965). Female dogs and their litters comprised the experimental unit, and all dogs in an experimental unit were treated on the same day 4 to 6 weeks after whelping. Mites and mite eggs were counted weekly on an untreated control group of six litters (15 pups) and on a group of six litters (14 pups) treated with 65% permethrin. Pups in the untreated control group maintained high numbers of Cheyletiella yasguri throughout the 14- to 21-day observation period. No mites or mite eggs were detected on dogs within 7 to 21 days after application of 65% permethrin. No adverse reactions were noted during the study. Clinical signs of infestation with C. yasguri--which included skin irritation, thickening of the stratum corneum, scratching with resultant scabs, pruritus, and flaky, scaly skin-were eliminated when mites were killed by the 65% permethrin formulation.

Larval Chigger Mites Collected from Small Mammals in 3 Provinces, Korea

PubMed Central

Lee, In-Yong; Song, Hyeon-Je; Choi, Yeon-Joo; Shin, Sun-Hye; Choi, Min-Kyung; Kwon, So-Hyun; Shin, E-Hyun; Park, Chan; Kim, Heung-Chul; Klein, Terry A.; Park, Kyung-Hee

2014-01-01

A total of 9,281 larval chigger mites were collected from small mammals captured at Hwaseong-gun, Gyeonggi-do (Province) (2,754 mites from 30 small mammals), Asan city, Chungcheongnam-do (3,358 mites from 48 mammals), and Jangseong-gun, Jeollanam-do (3,169 for 62 mammals) from April-November 2009 in the Republic of Korea (= Korea) and were identified to species. Leptotrombidium pallidum was the predominant species in Hwaseong (95.8%) and Asan (61.2%), while Leptotrombidium scutellare was the predominant species collected from Jangseong (80.1%). Overall, larval chigger mite indices decreased from April (27.3) to June (4.9), then increased in September (95.2) and to a high level in November (169.3). These data suggest that L. pallidum and L. scutellare are the primary vectors of scrub typhus throughout their range in Korea. While other species of larval chigger mites were also collected with some implications in the transmission of Orientia tsutsugamushi, they only accounted for 11.2% of all larval chigger mites collected from small mammals. PMID:24850971

Experimental study on possible transmission of the bacterium Erysipelothrix rhusiopathiae to chickens by the poultry red mite, Dermanyssus gallinae.

PubMed

Brännström, Sara; Hansson, Ingrid; Chirico, Jan

2010-04-01

The vector potential of the poultry red mite, Dermanyssus gallinae De Geer (Acari: Dermanyssidae), in relation to chicken erysipelas was investigated under experimental conditions. Chickens were inoculated intramuscularly with the bacterium Erysipelothrix rhusiopathiae, and mites were allowed to feed on the inoculated chickens for 5 days. After 20 days of starvation, the mites were allowed to feed on healthy chickens to enable transmission of bacteria. Blood samples were collected from the birds and analysed for the presence of E. rhusiopathiae, and ELISA tests were performed for seropositivity. The internal presence of E. rhusiopathiae in the mites after feeding of inoculated birds was also investigated. It could not be demonstrated that mites take up and transmit E. rhusiopathiae under the experimental conditions described. However, since there are case reports as well as other in vitro studies indicating the potential of D. gallinae to act as a reservoir and potential vector for infections agents, we cannot exclude the possibility that the red poultry mite transmits E. rhusiopathiae between chickens under field conditions.

Development and reproductive potential of Tyrophagus putrescentiae (Acari: Acaridae) on plant-parasitic nematodes and artificial diets.

PubMed

Abou El-Atta, Doaa Abd El-Maksoud; Osman, Mohamed Ali

2016-04-01

This study investigated development, reproduction and life table parameters of the astigmatid mold mite Tyrophagus putrescentiae (Schrank) (Acari: Acaridae) feeding on egg-masses or adult females of the nematode Meloidogyne incognita, egg-masses of the nematode Rotylenchulus reniformis, ras cheese or yeast at 25 ± 1 °C, 70 ± 10 % RH in the dark. Immature developmental times were shorter when the mite was fed females of M. incognita followed by yeast. Different prey/diet types had no significant effect on longevity and lifespan of both males and females. Daily oviposition rate (eggs/female/day) was highest for mites fed yeast (20.8 ± 1.8 eggs) and lowest for mites fed females of M. incognita (6.6 ± 0.5). Intrinsic rate of natural increase (r m) was highest for mites fed yeast compared to other prey/diet; no significant differences in r m were observed among mites fed on non-yeast diets. This result may suggest a role of T. putrescentiae as biocontrol agent of plant-parasitic nematodes and the yeast may be used for mite mass-production purposes.

Evidence of the efficacy and safety of house dust mite subcutaneous immunotherapy in elderly allergic rhinitis patients: a randomized, double-blind placebo-controlled trial.

PubMed

Bożek, Andrzej; Kołodziejczyk, Krzysztof; Kozłowska, Renata; Canonica, Giorgio Walter

2017-01-01

Allergen specific immunotherapy (AIT) in elderly patients is controversial, and there is still little evidence supporting the safety and efficacy of this treatment in this population. The study objective was to evaluate the safety and efficacy of AIT for house dust mite allergens in patients over 65 years of age with allergic rhinitis (AR) and a documented allergy to house dust mites. The primary endpoint was the change from baseline in the mean average adjusted symptom score (AAdSS) and the total combined rhinitis score (TCRS) difference in the least square means for the label compared to placebo. Fifty-eight AR elderly patients who were monosensitized to house dust mites were individually randomized in comparable numbers to one of two parallel groups with the following interventions: 2 years of perennial AIT using PURETHAL Mites or placebo. The symptoms and medication scores were presented as the AAdSS and TCRS. Quality of life, based on the rhinoconjunctivitis quality of life questionnaire (RQLQ), nasal allergen provocation responsiveness, serum allergen-specific IgG4 to D. pteronyssinus and D. farinae and Der p1 and Der p2 were monitored. The intent-to-treat population was analysed. After 24 months of AIT, AAdSS significantly decreased from 4.27 ± 1.58 to 1.82 ± 0.71 ( p  < 0.05). The TCRS was significantly decreased after 2 years of AIT. Serum-specific IgG4 against D. pteronyssinus , D. farinae, Der p1 , and Der p2 increased during the AIT trial in the study group. The RQLQ score was significantly improved in patients who received AIT, from 1.86 (95% CI 1.51-1.78) to 1.26 (95% CI 1.09-1.55). Two mild systemic anaphylactic reactions (degree I) were reported after injections in the active group during the AIT therapy. The DBPC trial showed AIT for house dust mite allergens was effective and safe in elderly patients with allergic rhinitis. This randomized, double-blinded placebo-controlled (DBPC) trial was conducted at one centre (ClinicalTrials.gov no. NCT03209245).

Characterisation of tropomyosin and paramyosin as vaccine candidate molecules for the poultry red mite, Dermanyssus gallinae.

PubMed

Wright, Harry W; Bartley, Kathryn; Huntley, John F; Nisbet, Alasdair J

2016-10-12

Dermanyssus gallinae is the most economically important haematophagous ectoparasite in commercial egg laying flocks worldwide. It infests the hens during the night where it causes irritation leading to restlessness, pecking and in extreme cases anaemia and increased cannibalism. Due to an increase in the occurrence of acaricide-resistant D. gallinae populations, new control strategies are required and vaccination may offer a sustainable alternative to acaricides. In this study, recombinant forms of D. gallinae tropomyosin (Der g 10) and paramyosin (Der g 11) were produced, characterised and tested as vaccine candidate molecules. The D. gallinae paramyosin (Der g 11) coding sequence was characterised and recombinant versions of Der g 11 and D. gallinae tropomyosin (Der g 10) were produced. Hens were immunised with the recombinant proteins and the resulting antibodies were fed to D. gallinae and mite mortality evaluated. Sections of mites were probed with anti- Der g 11 and Der g 10 antibodies to identify the tissue distribution of these protein in D. gallinae. The entire coding sequence of Der g 11 was 2,622 bp encoding 874 amino acid residues. Immunohistochemical staining of mite sections revealed that Der g 10 and Der g 11 were located throughout D. gallinae tissues. In phylogenetic analyses of these proteins both clustered with orthologues from tick species rather than with orthologues from astigmatid mites. Antibodies raised in hens against recombinant forms of these proteins significantly increased D. gallinae mortality, by 19 % for Der g 10 (P < 0.001) and by 23 % for Der g 11 (P = 0.009) when fed to the mites using an in vitro feeding device. This study has shown that Der g 10 and Der g 11 were located ubiquitously throughout D. gallinae and that antibodies raised against recombinant versions of these proteins can be used to significantly increase D. gallinae mortality in an in vitro feeding assay. When comparing archived data for all recombinant and native proteins assessed as vaccines using this in vitro feeding assay, Der g 10 and Der g 11 ranked highly and performed better than some of the pools of native proteins.

Varroa destructor Mites Can Nimbly Climb from Flowers onto Foraging Honey Bees.

PubMed

Peck, David T; Smith, Michael L; Seeley, Thomas D

2016-01-01

Varroa destructor, the introduced parasite of European honey bees associated with massive colony deaths, spreads readily through populations of honey bee colonies, both managed colonies living crowded together in apiaries and wild colonies living widely dispersed in natural settings. Mites are hypothesized to spread between most managed colonies via phoretically riding forager bees when they engage in robbing colonies or they drift between hives. However, widely spaced wild colonies show Varroa infestation despite limited opportunities for robbing and little or no drifting of bees between colonies. Both wild and managed colonies may also exchange mites via another mechanism that has received remarkably little attention or study: floral transmission. The present study tested the ability of mites to infest foragers at feeders or flowers. We show that Varroa destructor mites are highly capable of phoretically infesting foraging honey bees, detail the mechanisms and maneuvers by which they do so, and describe mite behaviors post-infestation.

Bioelimination of /sup 51/Cr and /sup 85/Sr by cockroaches, Gromphadorhina portentosa (Orthoptera: Blaberidae), as affected by mites, Gromphadorholaelaps schaeferi (parasitiformes: laelapidae)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schowalter, T.D.; Crossley, D.A. Jr.

1982-03-01

This paper describes rates of Chromium-51 and Strontium-85 assimilation and bioelimination by the hissing cockroach, Gromphadorhina portentosa (Schaum), when the symbiotic mite, Gromphadorholaelaps schaeferi Till, was present or removed. Mite-infested cockroaches had significantly higher rates of /sup 51/Cr elimination relative to mite-free cockroaches, implying more rapid gut clearance times. We did not find a significant mite effect on /sup 85/Sr elimination by the host, but mite effects could have been masked by the apparently unique process of nutrient assimilation and elimination by G. portentosa. Conventional models of radioactive tracer bioelimination predict a rapid initial loss of tracer due to gutmore » clearance, followed by a slower loss due to excretion of assimilated tracer. Our results indicated that assimilated /sup 85/Sr was eliminated earlier than unassimilated /sup 85/Sr was lost by defecation.« less

Mites (acari) infesting commensal rats in Suez Canal zone, Egypt.

PubMed

el Kady, G A; Shoukry, A; Ragheb, D A; el Said, A M; Habib, K S; Morsy, T A

1995-08-01

Mites are arthropods distinguished from ticks by usually being microscopical in size and have a hypostome unarmed with tooth-like anchoring processes. They are group in a number of suborders, each with super-families and families including many genera of medical and economic importance. In this paper, commensal rodents (Rattus norvegicus, R. r. alexandrinus and R. r. frugivorous) were surveyed in the Suez Canal Zone for their acari ectoparasites. Four species of mites were recovered. In a descending order of mite indices, they were Eulaelaps stabularis (4.83 on 6 rats), Laelaps nuttalli (3.11 on 27 rats), Ornithonyssus bacoti (1.66 on 9 rats) and Dermanyssus gallinae (0.66 on 24 rats). The overall mite indices in the three governorates were 3.66 in Suez, 2.82 in Ismailia and zero in Port Said. The medical and economic importance of the mites were discussed.

Pyroglyphid mites, xerophilic fungi and allergenic activity in dust from hospital mattresses.

PubMed

v d Lustgraaf, B; Jorde, W

1977-12-01

Dust from mattresses of different composition and age was analysed for mites, xerophilic fungi and allergenic activity. The mites of the genus Demodex were the most abundant (58.2 per cent). Also pyroglyphid mites occurred commonly (36.6 per cent). Pyroglyphid mites were present in small numbers (mean: 1 specimen/0.2 g of dust) in 12 out of the 17 older polyester-foam mattresses. The 11 cotton-horsechair mattresses and the newly used polyester-foam mattresses (three tested) were without them. The dust from the cotton-horsehair mattresses had a significantly higher allergenic activity than from those of polyester-foam. Xerophilic fungi were isolated in three out of 31 mattresses. The species isolated belonged to the genus Aspergillus and Eurotium. E. repens occurred most frequently. Disinfection of mattresses was suggested to have a negative influence on the occurrence of mites and fungi.

Neoseiulus paspalivorus, a predator from coconut, as a candidate for controlling dry bulb mites infesting stored tulip bulbs.

PubMed

Lesna, Izabela; da Silva, Fernando R; Sato, Yukie; Sabelis, Maurice W; Lommen, Suzanne T E

2014-06-01

The dry bulb mite, Aceria tulipae, is the most important pest of stored tulip bulbs in The Netherlands. This tiny, eriophyoid mite hides in the narrow space between scales in the interior of the bulb. To achieve biological control of this hidden pest, candidate predators small enough to move in between the bulb scales are required. Earlier experiments have shown this potential for the phytoseiid mite, Neoseiulus cucumeris, but only after the bulbs were exposed to ethylene, a plant hormone that causes a slight increase in the distance between tulip bulb scales, just sufficient to allow this predator to reach the interior part of the bulb. Applying ethylene, however, is not an option in practice because it causes malformation of tulip flowers. In fact, to prevent this cosmetic damage, bulb growers ventilate rooms where tulip bulbs are stored, thereby removing ethylene produced by the bulbs (e.g. in response to mite or fungus infestation). Recently, studies on the role of predatory mites in controlling another eriophyoid mite on coconuts led to the discovery of an exceptionally small phytoseiid mite, Neoseiulus paspalivorus. This predator is able to move under the perianth of coconuts where coconut mites feed on meristematic tissue of the fruit. This discovery prompted us to test N. paspalivorus for its ability to control A. tulipae on tulip bulbs under storage conditions (ventilated rooms with bulbs in open boxes; 23 °C; storage period June-October). Using destructive sampling we monitored predator and prey populations in two series of replicated experiments, one at a high initial level of dry bulb mite infestation, late in the storage period, and another at a low initial dry bulb mite infestation, halfway the storage period. The first and the second series involved treatment with N. paspalivorus and a control experiment, but the second series had an additional treatment in which the predator N. cucumeris was released. Taking the two series of experiments together we found that N. paspalivorus controlled the populations of dry bulb mites both on the outer scale of the bulbs as well as in the interior part of the bulbs, whereas N. cucumeris significantly reduced the population of dry bulb mites on the outer scale, but not in the interior part of the bulb. Moreover, N. paspalivorus was found predominantly inside the bulb, whereas N. cucumeris was only found on the outer scale, thereby confirming our hypothesis that the small size of N. paspalivorus facilitates access to the interior of the bulbs. We argue that N. paspalivorus is a promising candidate for the biological control of dry bulb mites on tulip bulbs under storage conditions in the Netherlands.

[Mites associated with two species of the genus Odontotaenius (Coleoptera: Passalidae) in Mexico].

PubMed

Barrios-Torres, Pilar Liliana; Villegas-Guzmán, Gabriel A

2015-09-01

Mites can establish association with different arthropods as coleopterans tamites scaraoaeicae ana Passalidae. Passalids are distributed in tropical and templates zones, and until now, more than 200 species of mites have been associated to them. One of the relationships between passalids and mites is the phoresy where one small animal (the phoretic) seeks out and attaches to another animal (the host) for transportation. Herein, we studied the mites associated to O. zodiacus and O. striatopunctatus; for this, 80 Odontotaenius with mites were reviewed; passalids were collected in and under decaying logs from six states of Mexico, and were individually kept in vials with 80% ethanol. The specimens were carried to the laboratory and mites removed with fine-pointed forceps under stereo microscope. The mites were stored with 80 % alcohol until some were cleared with lacto-phenol and mounted in Hoyer's solution. We found 1,945 mites belonging to 13 families (Acaridae, Ascidae, Diarthrophallidae, Digamasellidae, Diplogyniidae, Euzerconidae, Heterocheylidae, Histiostomatidae, Klinckowstroemiidae, Laelapidae, Megisthanidae, Trematuridae, and Uropodidae) and 42 species, being the most abundant species Anoelus sp. For O. striatopunctatus (16 specimens) we found 562 mites (95 female female, 34 male male, 197 hypopus, 234 deutonymph, 2 tritonymph) of 11 families and 22 species; the most abundant were Uropodidae (42 %) and Histiostomatidae (26 %). While for 0. zodiacus (64 specimens) were found 1,383 mites (300 female female, 204 male male, 608 hypopus, 139 deutonymphs, 133 tritonymphs) of 10 families and 30 species; the most abundant were: Diartrophallidae, Acaridae, and Histiostomatidae (23 % for the two first and 21 % for third). The high abundance and richness was in O. zodiacus, likewise Margalef (S') and Shanon-Winner (H') indexes were higher in this species (O. zodiacus S' = 4.05, H' = 2.2; O. striatopunctatus S' = 3.34, H' = 1.94), while Equity (EH) was similar to both hosts (0. zodiacus EH = 0.64; O. siriatopunctalus EH = 0.63). The mites were found principally in the protected zone of the passalid's body, as under elytron, membranous wings, and in the clefts of the ventral region of the passalid, and, in minor proportion, on the head and coxal regions. From our findings, 12 species were new records for the Mexican passalids: Abrotarsala cuneiformis, A. obesa, A. pyriformis, Brachytremella sp., Diarthrophallus cartwrighti, D. crinatus, Lombardiniella sp., Trichodiplogynium carlosi, T sahlbergi, T hirsutum and Trichodiplogynium sp., and additional studies may help describe and understand these mites-passalids associations.

Influence of Varroa Mite (Varroa destructor) Management Practices on Insecticide Sensitivity in the Honey Bee (Apis mellifera)

PubMed Central

Rinkevich, Frank D.; Danka, Robert G.; Healy, Kristen B.

2017-01-01

Since Varroa mites may cause devastating losses of honey bees through direct feeding, transmitting diseases, and increasing pathogen susceptibility, chemical and mechanical practices commonly are used to reduce mite infestation. While miticide applications are typically the most consistent and efficacious Varroa mite management method, miticide-induced insecticide synergism in honey bees, and the evolution of resistance in Varroa mites are reasonable concerns. We treated colonies with the miticide amitraz (Apivar®), used IPM practices, or left some colonies untreated, and then measured the effect of different levels of mite infestations on the sensitivity of bees to phenothrin, amitraz, and clothianidin. Sensitivity to all insecticides varied throughout the year among and within treatment groups. Clothianidin sensitivity decreased with increasing mite levels, but no such correlation was seen with phenothrin or amitraz. These results show that insecticide sensitivity is dynamic throughout the 5 months test. In-hive amitraz treatment according to the labeled use did not synergize sensitivity to the pesticides tested and this should alleviate concern over potential synergistic effects. Since IPM practices were largely ineffective at reducing Varroa mite infestation, reliance on chemical methods of Varroa mite management is likely to continue. However, miticides must be used judiciously so the long term effectiveness of these compounds can be maximized. These data demonstrate the complex and dynamic variables that contribute to honey bee colony health. The results underscore the importance of controlling for as many of these variables as possible in order to accurately determine the effects of each of these factors as they act alone or in concert with others. PMID:28085045

Relative acute effects of low pH and high iron on the hatching and survival of the water mite (Arrenurus manubriator) and the aquatic insect (Chironomus riparius)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rousch, J.M.; Simmons, T.W.; Kerans, B.L.

1997-10-01

The authors investigated the relative effects of low pH and high iron on a water mite, Arrenurus manubriator and an aquatic insect, Chironomus riparius. Eggs and active stages were exposed in static renewal toxicity tests to pH 6, 5, 4, 3, and 2, made by adding sulfuric acid to reconstituted soft water, or to iron levels of 200, 400, 600, 800, and 1,000 mg/L, made by adding ferrous sulfate to soft water at pH 4. Experiments were conducted at 22 C with a 16:8-h photoperiod, and treatments were replicated three times with at least nine individuals per treatment. Data weremore » analyzed with a logistic response function and one-way ANOVA for pH and iron tests, respectively. Egg hatching was reduced at pH 2 for midges and at pH 3 for mites. Iron had no effect on hatching for either species. Survival of midge larvae was partially reduced at pH 4, and survival of mite deutonymphs, larvae, female and male adults was reduced at pH 3. Survival of midge larvae, and mite deutonymphs and male adults was reduced at 400, 200, and 1,000 mg Fe/L, respectively. Mite female adults and larvae were unaffected by iron. Higher metabolic requirements of unfed immature stages, the gelatinous covering of mite and insect eggs, the longer incubation period of mite eggs, and the greater osmoregulatory potential of adult mites may have contributed to the differences observed.« less

Regional factors rather than forest type drive the community structure of soil living oribatid mites (Acari, Oribatida).

PubMed

Erdmann, Georgia; Scheu, Stefan; Maraun, Mark

2012-06-01

Most European forests are managed by humans. However, the manner and intensity of management vary. While the effect of forest management on above-ground communities has been investigated in detail, effects on the below-ground fauna remain poorly understood. Oribatid mites are abundant microarthropods in forest soil and important decomposers in terrestrial ecosystems. Here, we investigated the effect of four forest types (i.e., managed coniferous forests; 30 and 70 years old managed beech forests; natural beech forests) on the density, diversity and community structure of oribatid mites (Acari). The study was replicated at three regions in Germany: the Swabian Alb, the Hainich and the Schorfheide. To relate changes in oribatid mite community structure to environmental factors, litter mass, pH, C and N content of litter, fine roots and C content of soil were measured. Density of oribatid mites was highest in the coniferous forests and decreased in the order 30 years old, 70 years old, and natural beech forests. Mass of the litter layer and density of oribatid mites were strongly correlated indicating that the litter layer is an important factor regulating oribatid mite densities. Diversity of oribatid mites was little affected by forest type indicating that they harbor similar numbers of niches. Species composition differed between the forest types, suggesting different types of niches. The community structure of oribatid mites differed more strongly between the three regions than between the forest types indicating that regional factors are more important than effects associated with forest type.

Assessment of cross-reactivity among five species of house dust and storage mites.

PubMed

Saridomichelakis, Manolis N; Marsella, Rosanna; Lee, Kenneth W; Esch, Robert E; Farmaki, Rania; Koutinas, Alexander F

2008-04-01

In vitro cross-reactivity among two house dust (Dermatophagoides farinae, D. pteronyssinus) and three storage (Acarus siro, Tyrophagus putrescentiae, Lepidoglyphus destructor) mites was examined in 20 mite-sensitive dogs with natural occurring atopic dermatitis (group A), 13 high-IgE beagles experimentally sensitized to D. farinae (group B), and five healthy beagles (group C). Intradermal testing (IDT) and serology for allergen-specific IgE demonstrated that co-sensitization for all possible pairs of the five mites was generally 45% or higher among group A dogs. In the same dogs, enzyme-linked immunosorbent assay cross-inhibition results indicated that each one of D. farinae, A. siro and T. putrescentiae was a strong inhibitor of all the remaining mites, whereas D. pteronyssinus was a strong inhibitor of L. destructor. A high number of positive IDT and serology test results for D. pteronyssinus, A. siro, T. putrescentiae and L. destructor were recorded among group B dogs. No conclusive evidence of exposure to these mites was found upon analysis of dust samples from their environment and their food for the presence of mites and guanine. Also, the number of positive test results was generally higher among group B than among group C dogs. Enzyme-linked immunosorbent assay cross-inhibition revealed that D. farinae was a strong inhibitor of D. pteronyssinus, A. siro and T. putrescentiae. Collectively, these results demonstrated extensive in vitro cross-reactivity among house dust and/or storage mites that can explain false-positive results upon testing of dust mite-sensitive dogs with atopic dermatitis.

Sarcoptes scabiei on hedgehogs in New Zealand.

PubMed

Kriechbaum, Caroline; Pomroy, William; Gedye, Kristene

2018-03-01

European hedgehogs (Erinaceus europaeus) were introduced into New Zealand from Britain during the period from 1869 to the early 1900s. The only mite found on New Zealand hedgehogs in early studies was Caparinia tripilis, with Sarcoptes scabiei first being reported in 1996. The aim of this study was to investigate the prevalence of Sarcoptes infestation on hedgehogs in New Zealand, the number of mites found and the degree of mange observed. Dead hedgehogs were collected from veterinary clinics, rescue centres, members of the public and from road-kill. Twenty-one (55.3%) of the animals examined had visible skin lesions. Both Caparinia and Sarcoptes mites were identified on microscopic examination with Sarcoptes the most common, being found on over 70% of animals examined (n = 38). The numbers of mites recovered after brushing the head and body ranged from 1 to 5659 (median = 341 mites) with only six animals (22.2%) having fewer than 10 Sarcoptes mites found. Caparinia mites were seen on fewer animals and generally in very low numbers. These findings indicate a change in the mite populations on hedgehogs in New Zealand and that infected animals develop the debilitating hyperkeratotic form of sarcoptic mange without an accompanying hypersensitivity response limiting numbers of mites. Analysis of the cox 1 gene of Sarcoptes from two hedgehogs showed close alignment to sequences derived from a pig with one and from a dog with the second. More work needs to be undertaken to identify the source(s) of the Sarcoptes found on hedgehogs in New Zealand and whether other mammalian hosts may be infected from contact with hedgehogs.

House Dust Mite Prevalence in the House of Patients with Atopic Dermatitis in Mashhad, Iran

PubMed Central

Ziyaei, Toktam; Berenji, Fariba; Jabbari-Azad, Farahzad; Fata, Abdolmajid; Jarahi, Lida; Fereidouni, Mohammad

2017-01-01

Background: Being exposed to house dust mites intensifies atopic dermatitis. This study has investigated the contamination rate with Dermatophagoides mites in patient’s residential home with atopic dermatitis. Methods: In this cross-sectional study, 40 patients took part with atopic dermatitis (positive or negative for mites by prick Dermal Test). Samples were collected from 3 locations (living room, bedroom and bed) by vacuum cleaner. Dust samples (transferred to freezer −20 °C) were examined by direct method and flotation. The data were analyzed using statistical SPSS vr.20 software. Results: Twenty patients of positive prick test included 8 (40%) male and 12 (60%) female. The results of direct observation of mites: 7 cases (35%) in bedding sheets, 6 cases (30%) bedrooms’ carpet, 3 cases (15%) living room’s carpet. Twenty patients of negative prick test included 8 (40%) male and 12 (60%) female. Only mites were found (5%) in living room’s carpets of negative prick test patients. Dermatophagoides pteronyssinus was more frequent than Dermatophagoides farinae. (98% vs 83%). Conclusion: Fifty-five percent of residential homes of prick test positive patients and only 5% of residential homes of prick test negative patients were positive for mite. Sunshine provided home had fewer mites than home where sunshine is not provided. Prick test positive patients used handmade carpets more than machine made ones. In positive prick test patients, mites were found in bed sheet and bedroom’s carpet more than negative prick test patient’s sheets and carpets. PMID:29062855

The presence of quill mites (Gabucinia bicaudata) and lice (Struthiolipeurus struthionis) in ostrich wing feathers.

PubMed

Cooper, R G; El Doumani, H A A

2006-03-01

Quill mites (Gabucinia bicaudata) and lice (Struthiolipeurus struthionis) may infest ostrich feathers, resulting in skin damage, pruritus and excessive feather preening and loss. Four different feather types (prime white, femina extra wide, femina class 1, and femina short; n = 10) were collected. The quill mites and lice were removed with fine forceps, studied using a photographic optical microscope and counted microscopically at x 100 magnification following collection by sedimentation. They were placed in separate Petri dishes containing lactophenol solution and examined (x40 magnification). Anatomical features are described. The density of quill mites in all feather types of both wings was higher than that of the lice. There was no significant difference between the counts of both arthropods on the left wing and the right wing, respectively, except for the femina class 1 quill mites (P = 0.01). The femina extra wide feathers were a preferred habitat in both wings. Large standard deviations (quill mites left wing: 73 +/- 8; quill mites right wing: 69 +/- 7) suggested variations in the degree of migration between feather shafts or as a response to escape preening. It is recommended that ostriches be treated with an oral preparation of Ivermectin administered per os at a dosage rate of 0.2 mg/kg at 30-day intervals for quill mites, and with a 1-5 % Malathion dust at 14-day intervals for lice.

Resistance status of the carmine spider mite, Tetranychus cinnabarinus and the twospotted spider mite, Tetranychus urticae to selected acaricides on strawberries.

PubMed

Bi, Jian-Long; Niu, Zi-Mian; Yu, Lu; Toscano, Nick C

2016-02-01

The carmine spider mite, Tetranychus cinnabarinus (Boisduval) and the twospotted spider mite, Tetranychus urticae Koch, are serious pests of strawberries and many other horticultural crops. Control of these pests has been heavily dependent upon chemical acaricides. Objectives of this study were to determine the resistance status of these two pest species to commonly used acaricides on strawberries in a year-round intensive horticultural production region. LC90 of abamectin for adult carmine spider mites was 4% whereas that for adult twospotted spider mites was 24% of the top label rate. LC90s of spiromesifen, etoxazole, hexythiazox and bifenazate were 0.5%, 0.5%, 1.4% and 83% of their respective highest label rates for carmine spider mite eggs, 0.7%, 2.7%, 12.1% and 347% of their respective highest label rates for the nymphs. LC90s of spiromesifen, etoxazole, hexythiazox and bifenazate were 4.6%, 11.1%, 310% and 62% of their respective highest label rates for twospotted spider mite eggs, 3%, 13%, 432,214% and 15% of their respective highest label rates for the nymphs. Our results suggest that T. cinnabarinus have developed resistance to bifenazate and that the T. urticae have developed resistance to hexythiazox. These results strongly emphasize the need to develop resistance management strategies in the region. © 2014 Institute of Zoology, Chinese Academy of Sciences.

Leaf-morphology-assisted selection for resistance to two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) in carnations (Dianthus caryophyllus L).

PubMed

Seki, Kousuke

2016-10-01

The development of a cultivar resistant to the two-spotted spider mite has provided both ecological and economic benefits to the production of cut flowers. This study aimed to clarify the mechanism of resistance to mites using an inbred population of carnations. In the resistant and susceptible plants selected from an inbred population, a difference was recognised in the thickness of the abaxial palisade tissue by microscopic examination of the damaged leaf. Therefore, it was assumed that mites displayed feeding preferences within the internal leaf structure of the carnation leaf. The suitability of the host plant for mites was investigated using several cultivars selected using an index of the thickness from the abaxial leaf surface to the spongy tissue. The results suggested that the cultivar associated with a thicker abaxial tissue lowered the intrinsic rate of natural increase of the mites. The cultivars with a thicker abaxial tissue of over 120 µm showed slight damage in the field test. The ability of mites to feed on the spongy tissue during an early life stage from hatching to adult emergence was critical. It was possible to select a cultivar that is resistant to mites under a real cultivation environment by observing the internal structure of the leaf. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

The effect of hummingbird flower mites on nectar availability of two sympatric Heliconia species in a Brazilian Atlantic forest.

PubMed

Da Cruz, Denise Dias; Righetti De Abreu, Vanessa Holanda; Van Sluys, Monique

2007-09-01

Hummingbird flower mites feed and reproduce in flowers of host plants pollinated by hummingbirds, and use the nostrils and bill of the hummingbird to move from plant to plant. These mites compete with the pollinator for the nectar produced by flowers. An investigation was made of the relationship between the pattern of nectar production and the effects of hummingbird flower mites in the flowers of two sympatric species of Heliconia (Heliconiaceae). Nectar production was sampled by carrying out two experiments: 2-hour intervals and accumulated nectar. Flowers with and without mites were used in both experiments. Exclusion of mites increased nectar production, especially in accumulated daily production (a maximum of 49 % more nectar). Both Heliconia species had the same pattern of nectar production: a high concentration in the morning, which was progressively reduced as the day passed. This pattern of nectar production coincides with the behaviour of the pollinator, which makes more frequent visits in the morning, as observed in a previous study. The results suggest that the impact of mites on nectar availability of Heliconia is more important with regard to total volume of nectar produced irrespective of flower longevity. A high variation among individuals in nectar produced in the populations was also observed. Hummingbird flower mites strongly affect availability of nectar for hummingbirds.

The Effect of Hummingbird Flower Mites on Nectar Availability of Two Sympatric Heliconia Species in a Brazilian Atlantic Forest

PubMed Central

Da Cruz, Denise Dias; Righetti De Abreu, Vanessa Holanda; Van Sluys, Monique

2007-01-01

Background and Aims Hummingbird flower mites feed and reproduce in flowers of host plants pollinated by hummingbirds, and use the nostrils and bill of the hummingbird to move from plant to plant. These mites compete with the pollinator for the nectar produced by flowers. An investigation was made of the relationship between the pattern of nectar production and the effects of hummingbird flower mites in the flowers of two sympatric species of Heliconia (Heliconiaceae). Methods Nectar production was sampled by carrying out two experiments: 2-hour intervals and accumulated nectar. Flowers with and without mites were used in both experiments. Key Results Exclusion of mites increased nectar production, especially in accumulated daily production (a maximum of 49 % more nectar). Both Heliconia species had the same pattern of nectar production: a high concentration in the morning, which was progressively reduced as the day passed. This pattern of nectar production coincides with the behaviour of the pollinator, which makes more frequent visits in the morning, as observed in a previous study. Conclusions The results suggest that the impact of mites on nectar availability of Heliconia is more important with regard to total volume of nectar producted irrespective of flower longevity. A high variation among individuals in nectar produced in the populations was also observed. Hummingbird flower mites strongly affect availability of nectar for hummingbirds. PMID:17638712

Haematophagus Mites in Poultry Farms of Iran

PubMed Central

Rahbari, S; Nabian, S; Ronaghi, H

2009-01-01

Background: Blood sucking mites are important avian ectoparasites which being found on bird species worldwide. Their presence are problematic for the producers either through potential direct effects on weight gain, egg production, sperm production in roosters or as nuisance pests on worker handle hens and eggs. The aim of this study was pointing out of the status of haematophagus mites. Methods: Eight caged layer and four breeder flocks were visited, monitoring for the presence of chicken mites performed by removing and examining debris from poultry house, infested nesting material collected into zip lock plastic bags and at least 20 birds were also randomly selected to examine the presence of chicken mites. Mites obtained from each population were mounted in Hoyer’s medium on microscope slides and identified. All eight caged layer and four breeder flocks were inspected, which were infested with chicken blood feeding mites. Results: Massive infestations of Dermanyssus gallinae were common with huge numbers of parasites on birds, cages and the conveyor belts for egg. Only one farm from Mazandaran Province was infested to Ornithonyssus bursa. Conclusion: Dermanyssus gallinae was the most prevalent blood feeder mite in the breeder and caged layer flocks in Iran, while O. bursa was reported as a first record, which found only in a breeder flock in Mazanderan Province. It seems that its presence is limited into the area which affected by both warm and humid environmental conditions. PMID:22808378

Efficacy of Controlled Atmosphere Treatments to Manage Arthropod Pests of Dry-Cured Hams

PubMed Central

Hasan, Md. Mahbub; Aikins, Michael J.; Schilling, Wes; Phillips, Thomas W.

2016-01-01

Research here explored the use of controlled atmospheres (CA) for managing arthropod pests that infest dry-cured hams. Experiments were conducted with low oxygen (O2) achieved with low pressure under a vacuum, high carbon dioxide (CO2), and ozone (O3). Results showed that both low O2 and high CO2 levels required exposures up to 144 h to kill 100% of all stages of red-legged ham beetle, Necrobia rufipes (De Geer) (Coleoptera: Cleridae) and ham mite Tyrophagus putrescentiae (Schrank) (Sarcoptiformes: Acaridae) at 23 °C. In addition, both low O2 and high CO2 had no significant mortality against the ham beetle and ham mites at short exposures ranging from 12 to 48 h. Ham beetles were more tolerant than ham mites to an atmosphere of 75.1% CO2 and low pressure of 25 mm Hg, which imposed an atmosphere estimated at 0.9% O2. Both low O2 and high CO2 trials indicated that the egg stages of both species were more tolerant than other stages tested, but N. rufipes eggs and pupae were more susceptible than larvae and adults to high concentration ozone treatments. The results indicate that O3 has potential to control ham beetles and ham mites, particularly at ≈166 ppm in just a 24 h exposure period, but O3 is known from other work to have poor penetration ability, thus it may be more difficult to apply effectively than low O2 or high CO2. would be. CA treatment for arthropod pests of dry-cured hams show promise as components of integrated pest management programs after methyl bromide is no longer available for use. PMID:27598209

A review of introductions of pathogens and nematodes for classical biological control of insects and mites

Treesearch

Ann E. Hajek; Michael L. McManus; Italo Delalibera Junior

2007-01-01

Compared with parasitoids and predators, classical biological control programs targeting arthropod pests have used pathogens and nematodes very little. However, some pathogens and nematodes that have been introduced have become established and provided excellent control and have been introduced in increasing numbers of areas over decades, often after distributions of...

Origin and higher-level diversification of acariform mites - evidence from nuclear ribosomal genes, extensive taxon sampling, and secondary structure alignment.

PubMed

Pepato, A R; Klimov, P B

2015-09-02

Acariformes is the most species-rich and morphologically diverse radiation of chelicerate arthropods, known from the oldest terrestrial ecosystems. It is also a key lineage in understanding the evolution of this group, with the most vexing question whether mites, or Acari (Parasitiformes and Acariformes) is monophyletic. Previous molecular studies recovered Acari either as monophyletic or non-monophyletic, albeit with a limited taxon sampling. Similarly, relationships between basal acariform groups (include little-known, deep-soil 'endeostigmatan' mites) and major lineages of Acariformes (Sarcoptiformes, Prostigmata) are virtually unknown. We infer phylogeny of chelicerate arthropods, using a large and representative dataset, comprising all main in- and outgroups (228 taxa). Basal diversity of Acariformes is particularly well sampled. With this dataset, we conduct a series of phylogenetically explicit tests of chelicerate and acariform relationships and present a phylogenetic framework for internal relationships of acariform mites. Our molecular data strongly support a diphyletic Acari, with Acariformes as the sister group to Solifugae (PP =1.0; BP = 100), the so called Poecilophysidea. Among Acariformes, some representatives of the basal group Endeostigmata (mainly deep-soil mites) were recovered as sister-groups to the remaining Acariformes (i. e., Trombidiformes + and most of Sarcoptiformes). Desmonomatan oribatid mites (soil and litter mites) were recovered as the monophyletic sister group of Astigmata (e. g., stored product mites, house dust mites, mange mites, feather and fur mites). Trombidiformes (Sphaerolichida + Prostigmata) is strongly supported (PP =1.0; BP = 98-100). Labidostommatina was inferred as the basal lineage of Prostigmata. Eleutherengona (e. g., spider mites) and Parasitengona (e. g., chiggers, fresh water mites) were recovered as monophyletic. By contrast, Eupodina (e. g., snout mites and relatives) was not. Marine mites (Halacaridae) were traditionally regarded as the sister-group to Bdelloidea (Eupodina), but our analyses show their close relationships to Parasitengona. Non-trivial relationships recovered by our analyses with high support (i.e., basal arrangement of endeostigmatid lineages, the position of marine mites, polyphyly of Eupodina) had been proposed by previous underappreciated morphological studies. Thus, we update currently the accepted taxonomic classification to reflect these results: the superfamily Halacaroidea Murray, 1877 is moved from the infraorder Eupodina Krantz, 1978 to Anystina van der Hammen, 1972; and the subfamily Erythracarinae Oudemans, 1936 (formerly in Anystidae Oudemans, 1902) is elevated to family rank, Erythracaridae stat. ressur., leaving Anystidae only with the nominal subfamily. Our study also shows that a clade comprising early derivative Endeostigmata (Alycidae, Nanorchestidae, Nematalycidae, and maybe Alicorhagiidae) should be treated as a taxon with the same rank as Sarcoptiformes and Trombidiformes, and the scope of the superfamily Bdelloidea should be changed. Before turning those findings into nomenclatural changes, however, we consider that our study calls for (i) finding shared apomorphies of the early derivative Endeostigmata clade and the clade including the remaining Acariformes; (ii) a well-supported hypothesis for Alicorhagiidae placement; (iii) sampling the families Proterorhagiidae, Proteonematalycidae and Grandjeanicidae not yet included in molecular analyses; (iv) undertake a denser sampling of clades traditionally placed in Eupodina, Anystina (Trombidiformes) and Palaeosomata (Sarcoptiformes), since consensus networks and Internode certainty (IC) and IC All (ICA) indices indicate high levels of conflict in these tree regions. Our study shows that regions of ambiguous alignment may provide useful phylogenetic signal when secondary structure information is used to guide the alignment procedure and provides an R implementation to the Bayesian Relative Rates test.

Virulence and site of infection of the fungus, Hirsutella thompsonii, to the honey bee ectoparasitic mite, Varroa destructor.

PubMed

Peng, Christine Y S; Zhou, Xinsheng; Kaya, Harry K

2002-11-01

The Varroa mite, Varroa destructor, is recognized as the most serious pest of both managed and feral Western honey bee (Apis mellifera) in the world. The mite has developed resistance to fluvalinate, an acaricide used to control it in beehives, and fluvalinate residues have been found in the beeswax, necessitating an urgent need to find alternative control measures to suppress this pest. Accordingly, we investigated the possibility of using the fungus, Hirsutella thompsonii, as a biocontrol agent of the Varroa mite. Among the 9 isolates of H. thompsonii obtained from the University of Florida and the USDA, only the 3 USDA isolates (ARSEF 257, 1947 and 3323) were infectious to the Varroa mite in laboratory tests. The mite became infected when it was allowed to walk on a sporulating H. thompsonii culture for 5 min. Scanning electron micrographs revealed that the membranous arolium of the mite leg sucker is the focus of infection where the fungal conidia adhered and germinated. The infected mites died from mycosis, with the lethal times to kill 50% (LT(50)s) dependent on the fungal isolates. Thus, the LT(50)s were 52.7, 77.2, and 96.7h for isolates 3323, 257, and 1947, respectively. Passage of H. thompsonii through Varroa mite three times significantly reduced the LT(50)s of isolates 257 and 1947 (P<0.05) but not the LT(50) of isolate 3323. The fungus did not infect the honey bee in larval, prepupal, pupal, and adult stages under our laboratory rearing conditions. Our encouraging results suggest that some isolates of H. thompsonii have the potential to be developed as a biocontrol agent for V. destructor. However, fungal infectivity against the mites under beehive conditions needs to be studied before any conclusion can be made.

Mites of sheep and goats in Oromia Zone of Amhara Region, North Eastern Ethiopia: species, prevalence and farmers awareness.

PubMed

Yasine, Ahmed; Kumsa, Bersissa; Hailu, Yacob; Ayana, Dinka

2015-05-24

Mites are one of the most common and widely distributed ectoparasites of small ruminants in Ethiopia, contributing to major hindrances in livestock productivity in the country. Despite of this fact, specific study was not conducted on mites of small ruminants in Ethiopia. Therefore, the present study was performed from October 2009 to May 2010 to determine the prevalence and species composition of mites in three agroecological zones in north eastern Ethiopia. In addition, a questionnaire survey on mites was conducted to assess the control practices and awareness of farmers in the study areas. Out of a total of 1280 sheep and 1264 goats examined, 97(7.6 %) of sheep and 174(13.8 %) goats were infested with one or more species of mites. In goats an overall prevalence of 10.3 % Sarcoptes, 2.8 % Demodex and 0.6 % Psoroptes were recorded whereas in sheep an overall prevalence of 3.5 % Sarcoptes, 2.1 % Demodex and 1.6 % Psoroptes were observed. Sarcoptes (P = 0.03; OR = 2.1) and Demodex (OR = 3.25; p = 0.004) were significantly more common in young than in adult sheep. Demodectic mange was significantly higher in young (4.1 %) compared to adult (2.3 %) goats (OR = 2.2; P = 0.02). Significantly higher (P < 0.01) overall prevalence of sarcoptic and demodectic mites in both sheep and goats with poor than with good body condition was recorded. Results of the questionnaire survey supported results of our cross-sectional study. This study demonstrates high prevalence of mange mites in sheep and goats of the study area. The study revealed that Sarcoptes is the predominant mite in both sheep and goats. Animal owners and veterinarians should consider mite control in small ruminants as part of the routine ectoparasite control in Ethiopia.

Scabies Mite Peritrophins Are Potential Targets of Human Host Innate Immunity

PubMed Central

Holt, Deborah C.; Kemp, Dave J.; Fischer, Katja

2011-01-01

Background Pruritic scabies lesions caused by Sarcoptes scabiei burrowing in the stratum corneum of human skin facilitate opportunistic bacterial infections. Emerging resistance to current therapeutics emphasizes the need to identify novel targets for protective intervention. We have characterized several protein families located in the mite gut as crucial factors for host-parasite interactions. Among these multiple proteins inhibit human complement, presumably to avoid complement-mediated damage of gut epithelial cells. Peritrophins are major components of the peritrophic matrix often found in the gut of arthropods. We hypothesized that a peritrophin, if abundant in the scabies mite gut, could be an activator of complement. Methodology/Principal Findings A novel full length scabies mite peritrophin (SsPTP1) was identified in a cDNA library from scabies mites. The amino acid sequence revealed four putative chitin binding domains (CBD). Recombinant expression of one CBD of the highly repetitive SsPTP1 sequence as TSP-hexaHis-fusion protein resulted in soluble protein, which demonstrated chitin binding activity in affinity chromatography assays. Antibodies against a recombinant SsPTP1 fragment were used to immunohistochemically localize native SsPTP1 in the mite gut and in fecal pellets within the upper epidermis, co-localizing with serum components such as host IgG and complement. Enzymatic deglycosylation confirmed strong N- and O-glycosylation of the native peritrophin. Serum incubation followed by immunoblotting with a monoclonal antibody against mannan binding lectin (MBL), the recognition molecule of the lectin pathway of human complement activation, indicated that MBL may specifically bind to glycosylated SsPTP1. Conclusions/Significance This study adds a new aspect to the accumulating evidence that complement plays a major role in scabies mite biology. It identifies a novel peritrophin localized in the mite gut as a potential target of the lectin pathway of the complement cascade. These initial findings indicate a novel role of scabies mite peritrophins in triggering a host innate immune response within the mite gut. PMID:21980545

Macrodinychus mites as parasitoids of invasive ants: an overlooked parasitic association.

PubMed

Lachaud, Jean-Paul; Klompen, Hans; Pérez-Lachaud, Gabriela

2016-07-21

Mites are frequent ant symbionts, yet the exact nature of their interactions with their hosts is poorly known. Generally, myrmecophilous mites show adaptations for dispersal through phoresis, but species that lack such an adaptation may have evolved unusual specialized relationships with their hosts. The immature stages of Macrodinychus multispinosus develop as ectoparasitoids of pupae of the invasive ant Paratrechina longicornis. Feeding stages show regressed locomotor appendages. These mites complete their development on a single host, sucking all of its body content and therefore killing it. Locally high proportions of parasitized host pupae suggest that M. multispinosus could serve as a biological control agent. This is the ninth species of Macrodinychus reported as ant parasite, and the third known as parasitoid of invasive ants, confirming a unique habit in the evolution of mite feeding strategies and suggesting that the entire genus might be parasitic on ants. Several mites' characteristics, such as their protective morphology, possible viviparity, lack of a specialized stage for phoretic dispersal, and low host specificity, combined with both the general low aggressiveness of invasive P. longicornis towards other ants and its possible susceptibility to generalist ectoparasites would account for the host shift in native macrodinychid mites.

Selection of Apis mellifera workers by the parasitic mite Varroa destructor using host cuticular hydrocarbons.

PubMed

Del Piccolo, F; Nazzi, F; Della Vedova, G; Milani, N

2010-05-01

The parasitic mite, Varroa destructor, is the most important threat for apiculture in most bee-keeping areas of the world. The mite is carried to the bee brood cell, where it reproduces, by a nurse bee; therefore the selection of the bee stage by the parasite could influence its reproductive success. This study investigates the role of the cuticular hydrocarbons of the European honeybee (Apis mellifera) in host-selection by the mite. Preliminary laboratory bioassays confirmed the preference of the varroa mite for nurse bees over pollen foragers. GC-MS analysis of nurse and pollen bees revealed differences in the cuticular hydrocarbons of the two stages; in particular, it appeared that pollen bees have more (Z)-8-heptadecene than nurse bees. Laboratory experiments showed that treatment of nurse bees with 100 ng of the pure compound makes them repellent to the varroa mite. These results suggest that the mite can exploit the differences in the cuticular composition of its host for a refined selection that allows it to reach a brood cell and start reproduction. The biological activity of the alkene encourages further investigations for the development of novel control techniques based on this compound.

Novel insights into an old disease: recent developments in scabies mite biology.

PubMed

Holt, Deborah C; Fischer, Katja

2013-04-01

Scabies is a serious disease of both humans and other animals caused by infestation of the skin with the ectoparasitic mite Sarcoptes scabiei. Our current understanding of scabies mite biology and disease processes is far outweighed by the significant, worldwide impact of the disease. This review summarizes the recent data which furthers our knowledge of mite biology, host specificity and parasite host evasion mechanisms. Recent data concords with the previous work demonstrating limited gene flow between different host-associated populations of scabies mites. This evidence of the host specificity of scabies mites has important implications for disease control programmes. Other studies have begun to decipher the molecular basis of the complex host-parasite interactions underlying scabies infestations. Scabies mites have developed complex mechanisms to interfere with the host defence processes that may also enhance the survival of the associated skin microbiome, consistent with the epidemiological evidence. Recently developed natural host models of scabies are valuable tools to further study the disease processes and to trial novel therapeutic agents. Although significant progress has been made, further research is needed to understand the biology, host-parasite interactions and pathogenesis of this ubiquitous parasite.

Testing for non-target effects of spinosad on twospotted spider mites and their predator Phytoseiulus persimilis under greenhouse conditions.

PubMed

Holt, Kiffnie M; Opit, George P; Nechols, James R; Margolies, David C

2006-01-01

The compatibility of the selective insecticide spinosad (Conserve SC), at rates recommended for thrips control in greenhouses, with release of the predatory mite Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) to control spider mites, was investigated in a crop of ivy geranium Pelargonium peltatum, cultivar 'Amethyst 96.' Plants were inoculated with twospotted spider mites, Tetranychus urticae Koch (Acari: Tetranychidae), 2 weeks before treatments were applied. There were three treatment variables, each at two levels: predators (released or not), spray application (water or Conserve SC at 2 ml/3.79 l), and timing of spray (1 day before or after predators were released). Twospotted spider mite populations then were sampled twice each week over a three-week period. The application or timing of spinosad had no effect on the ability of the predator to reduce the population of spider mites. Spider mite populations in the no-predator treatment continued to expand over the course of the experiment, while those in the predator-release treatment declined. We conclude that P. persimilis can be used in conjunction with spinosad on ivy geraniums without causing obvious detrimental effects to this predator or leading to a reduction in biological control.

Spider mite web mediates anti-predator behaviour

PubMed Central

Lemos, Felipe; Sarmento, Renato Almeida; Pallini, Angelo; Dias, Cleide Rosa; Sabelis, Maurice W.

2010-01-01

Herbivores suffer significant mortality from predation and are therefore subject to natural selection on traits promoting predator avoidance and resistance. They can employ an array of strategies to reduce predation, for example through changes in behaviour, morphology and life history. So far, the anti-predator response studied most intensively in spider mites has been the avoidance of patches with high predation risk. Less attention has been given to the dense web produced by spider mites, which is a complex structure of silken threads that is thought to hinder predators. Here, we investigate the effects of the web produced by the red spider mite, Tetranychus evansi Baker & Pritchard, on its interactions with the predatory mite, Phytoseiulus longipes Evans. We tested whether female spider mites recognize predator cues and whether these can induce the spider mites to produce denser web. We found that the prey did not produce denser web in response to such cues, but laid more eggs suspended in the web, away from the leaf surface. These suspended eggs suffered less from predation by P. longipes than eggs that were laid on the leaf surface under the web. Thus, by altering their oviposition behaviour in response to predator cues, females of T. evansi protect their offspring. PMID:20191311

Population structure of the predatory mite Neoseiulus womersleyi in a tea field based on an analysis of microsatellite DNA markers

PubMed Central

Todokoro, Yasuhiro; Higaki, Tomomi

2010-01-01

The predatory mite Neoseiulus womersleyi (Schicha) (Acari: Phytoseiidae) is an important natural enemy of the Kanzawa spider mite, Tetranychus kanzawaki Kishida (Acari: Tetranychidae), in tea fields. Attraction and preservation of natural enemies by habitat management to reduce the need for acaricide sprays is thought to enhance the activity of N. womersleyi. To better conserve N. womersleyi in the field, however, it is essential to elucidate the population genetic structure of this species. To this end, we developed ten microsatellite DNA markers for N. womersleyi. We then evaluated population structure of N. womersleyi collected from a tea field, where Mexican sunflower, Tithonia rotundifolia (Mill.), was planted to preserve N. womersleyi. Seventy-seven adult females were collected from four sites within 200 m. The fixation indexes FST among subpopulations were not significantly different. The kinship coefficients between individuals did not differ significantly within a site as a function of the sampling dates, but the coefficients gradually decreased with increasing distance. Bayesian clustering analysis revealed that the population consisted of three genetic clusters, and that subpopulations within 100 m, including those collected on T. rotundifolia, were genetically similar to each other. Given the previously observed population dynamics of N. womersleyi, it appears that the area inhabited by a given cluster of the mite did not exceed 100 m. The estimation of population structure using microsatellite markers will provide valuable information in conservation biological control. PMID:20625919

Toxicological evaluation of genetically modified cotton (Bollgard) and Dipel WP on the non-target soil mite Scheloribates praeincisus (Acari: Oribatida).

PubMed

Oliveira, Anibal R; Castro, Thiago R; Capalbo, Deise M F; Delalibera, Italo

2007-01-01

Insecticides derived from the bacterium Bacillus thuringiensis (Bt) and plants genetically modified (GM) to express B. thuringiensis toxins are important alternatives for insect pest control worldwide. Risk assessment of B. thuringiensis toxins to non-target organisms has been extensively studied but few toxicological tests have considered soil invertebrates. Oribatid mites are one of the most diverse and abundant arthropod groups in the upper layers of soil and litter in natural and agricultural systems. These mites are exposed to the toxic compounds of GM crops or pesticides mainly when they feed on vegetal products incorporated in the soil. Although some effects of B. thuringiensis products on Acari have been reported, effects on oribatid mites are still unknown. This study investigated the effects of the ingestion of Bt cotton Bollgard and of the B. thuringiensis commercial product Dipel WP on the pantropical species Scheloribates praeincisus (Scheloribatidae). Ingestion of Bollgard and Dipel did not affect adult and immature survivorship and food consumption (estimated by number of fecal pellets produced daily) or developmental time of immature stages of S. praeincisus. These results indicate the safety of Bollgard and Dipel to S. praeincisus under field conditions where exposition is lower and other food sources besides leaves of Bt plants are available. The method for toxicological tests described here can be adapted to other species of Oribatida, consisting on a new option to risk assessment studies.

Field bioassay of Metarhizium anisopliae strains to control the poultry red mite Dermanyssus gallinae.

PubMed

Tavassoli, M; Allymehr, M; Pourseyed, S H; Ownag, A; Bernousi, I; Mardani, K; Ghorbanzadegan, M; Shokrpoor, S

2011-06-10

The poultry red mite, Dermanyssus gallinae is one of the most economically deleterious ectoparasite of laying hens worldwide. To evaluate the efficacy of three strains (V245, 3247 and 715C) of entomopathogenic fungus Metarhizium anisopliae with potential as acaricides against D. gallinae, this investigation was carried out in a commercial caged laying poultry farm in Naghedeh, West Azarbaijan of Iran. The parasite infestation already existed in the farm. Sunflower oil suspension of all fungal strains, each in two concentrations (1×10(7) and 1×10(9) conidia/ml) were used separately as spray on hens and cages, and in the control group the cages were only sprayed with sunflower oil and sterile distilled water. For estimating the population rate of mites before and after treatment, special cardboard traps were fixed to cages during a 1-month period. The traps were placed on weeks -1, 0, 1, 2 and 3 and always removed after 1 w. The results showed that the population rates post fungal treatment with the lower concentration were not significantly different compared to the control group. However, the reduction in mite numbers induced by all three strains at the concentration of 1×10(9) conidia/ml was significantly higher than the control (P<0.05). The results revealed that under field conditions, higher concentrations of M. anisopliae will be required for controlling D. gallinae. Copyright © 2011 Elsevier B.V. All rights reserved.

Formulation and characterization of garlic (Allium sativum L.) essential oil nanoemulsion and its acaricidal activity on eriophyid olive mites (Acari: Eriophyidae).

PubMed

Mossa, Abdel-Tawab H; Afia, Sahar I; Mohafrash, Samia M M; Abou-Awad, Badawi A

2018-04-01

Green and nanoacaricides including essential oil (EO) nanoemulsions are important compounds to provide new, active, safe acaricides and lead to improvement of avoiding the risk of synthetic acaricides. This study was carried out for the first time on eriophyid mites to develop nanoemulsion of garlic essential oil by ultrasonic emulsification and evaluate its acaricidal activity against the two eriophyid olive mites Aceria oleae Nalepa and Tegolophus hassani (Keifer). Acute toxicity of nanoemulsion was also studied on male rats. Garlic EO was analyzed by gas chromatography-mass spectrometry (GC-MS), and the major compounds were diallyl sulfide (8.6%), diallyl disulfide (28.36%), dimethyl tetrasulfide (15.26%), trisulfide,di-2-propenyl (10.41%), and tetrasulfide,di-2-propenyl (9.67%). Garlic oil nanoemulsion with droplet size 93.4 nm was formulated by ultrasonic emulsification for 35 min. Emulsification time and oil and surfactant ratio correlated to the emulsion droplet size and stability. The formulated nanoemulsion showed high acaricidal activity against injurious eriophyid mites with LC 50 298.225 and 309.634 μg/ml, respectively. No signs of nanoemulsion toxicity were noted in treating rats; thus, it may be considered non-toxic to mammals. Stability of garlic oil nanoemulsion, high acaricidal activity, and the absence of organic toxic solvents make the formulation that may be a possible acaricidal product. Results suggest the possibility of developing suitable natural nanoacaricide from garlic oil.

Rediscovery of Meristaspis lateralis (Kolenati) (Acari: Mesostigmata: Spinturnicidae) parasitizing the Egyptian fruit bat, Rousettus aegyptiacus (Geoffroy) (Mammalia: Chiroptera), with a key to mites of bats in Egypt.

PubMed

Negm, Mohamed W; Fakeer, Mahmoud M

2014-04-01

Faunistic information about bat mites in Egypt is scarce. Collection records of parasitic mites, Meristaspis lateralis (Kolenati, 1856) (Mesostigmata: Spinturnicidae), are reported from the Egyptian fruit bat, Rousettus aegyptiacus (Geoffroy, 1810) (Mammalia: Chiroptera) in Assiut Governorate, Egypt. Seven species of bat mites are recognized from Egypt to date. A host-parasite checklist and an identification key to these species are presented.

A case of gamasoidosis associated with exposure to a wild lorikeet feeding tray.

PubMed

Warren, Matthew; Tritton, Sara; Abbott, Nicola Cd; Sim, Sarah; Strutton, Geoffrey M; Soyer, H Peter

2016-05-01

Gamasoidosis (acariasis, avian-mite dermatitis or bird-mite dermatitis) is caused by members of the mite superfamily Dermanyssoidea. The mites lay their eggs on the nest of the birds they feed on. The also leave the nest and feed on humans if there is no bird host available. The bites result in urticated plaques and papules. Here we present a case of gamasoidosis from exposure to a wild lorikeet feeding tray. © 2015 The Australasian College of Dermatologists.

Sarcoptes scabiei Mites Modulate Gene Expression in Human Skin Equivalents

PubMed Central

Morgan, Marjorie S.; Arlian, Larry G.; Markey, Michael P.

2013-01-01

The ectoparasitic mite, Sarcoptes scabiei that burrows in the epidermis of mammalian skin has a long co-evolution with its hosts. Phenotypic studies show that the mites have the ability to modulate cytokine secretion and expression of cell adhesion molecules in cells of the skin and other cells of the innate and adaptive immune systems that may assist the mites to survive in the skin. The purpose of this study was to identify genes in keratinocytes and fibroblasts in human skin equivalents (HSEs) that changed expression in response to the burrowing of live scabies mites. Overall, of the more than 25,800 genes measured, 189 genes were up-regulated >2-fold in response to scabies mite burrowing while 152 genes were down-regulated to the same degree. HSEs differentially expressed large numbers of genes that were related to host protective responses including those involved in immune response, defense response, cytokine activity, taxis, response to other organisms, and cell adhesion. Genes for the expression of interleukin-1α (IL-1α) precursor, IL-1β, granulocyte/macrophage-colony stimulating factor (GM-CSF) precursor, and G-CSF precursor were up-regulated 2.8- to 7.4-fold, paralleling cytokine secretion profiles. A large number of genes involved in epithelium development and keratinization were also differentially expressed in response to live scabies mites. Thus, these skin cells are directly responding as expected in an inflammatory response to products of the mites and the disruption of the skin’s protective barrier caused by burrowing. This suggests that in vivo the interplay among these skin cells and other cell types, including Langerhans cells, dendritic cells, lymphocytes and endothelial cells, is responsible for depressing the host’s protective response allowing these mites to survive in the skin. PMID:23940705

Prevalence of house dust mites and dermatophagoides group 1 antigens collected from bedding, skin and hair coat of dogs in south-west England.

PubMed

Jackson, Anna P; Foster, Aiden P; Hart, Barbara J; Helps, Chris R; Shaw, Susan E

2005-02-01

The house dust mites Dermatophagoides farinae (Df) and D. pteronyssinus (Dpt) are commonly implicated as allergens causing canine atopic dermatitis in the UK. However, there are few studies that characterize the exposure of UK pet dogs to these mites. The objectives of this study were to determine the prevalence of the mite species on the skin, hair coat and bedding of a population of pet dogs. Dust samples (n = 68) were collected from both dogs and their beds using a standardized vacuuming technique and stored at -20 degrees C. Mites were identified using accepted morphological criteria. House dust mite allergen concentrations were assayed using standardized ELISA for Dpt and Df group 1 allergens (Der p 1 and Der f 1). Mites were identified in 15/68 samples (22%) and Dpt was the most common. Df mites were not present. Der p 1 allergens were detected in 60% of samples, and Der f 1 in 6% of samples. There were no significant differences between the number of Der p 1 positive samples from dogs and the number of those from their bedding, or between the average Der p 1 concentrations from dogs and the number of those from their bedding. Contrary to studies elsewhere in Europe and the USA, these findings support studies of human asthma patients in the UK, where exposure to Df is rare, but to Dpt is common. As the prevalence of positive intradermal and serological reactions to Df in atopic dogs is high, further investigations are warranted to clarify true Df hypersensitivity or potential immunological cross-reactivity between mite allergens.

Draft genome of the honey bee ectoparasitic mite, Tropilaelaps mercedesae, is shaped by the parasitic life history.

PubMed

Dong, Xiaofeng; Armstrong, Stuart D; Xia, Dong; Makepeace, Benjamin L; Darby, Alistair C; Kadowaki, Tatsuhiko

2017-03-01

The number of managed honey bee colonies has considerably decreased in many developed countries in recent years and ectoparasitic mites are considered as major threats to honey bee colonies and health. However, their general biology remains poorly understood. We sequenced the genome of Tropilaelaps mercedesae, the prevalent ectoparasitic mite infesting honey bees in Asia, and predicted 15 190 protein-coding genes that were well supported by the mite transcriptomes and proteomic data. Although amino acid substitutions have been accelerated within the conserved core genes of two mites, T. mercedesae and Metaseiulus occidentalis, T. mercedesae has undergone the least gene family expansion and contraction between the seven arthropods we tested. The number of sensory system genes has been dramatically reduced, but T. mercedesae contains all gene sets required to detoxify xenobiotics. T. mercedesae is closely associated with a symbiotic bacterium (Rickettsiella grylli-like) and Deformed Wing Virus, the most prevalent honey bee virus. T. mercedesae has a very specialized life history and habitat as the ectoparasitic mite strictly depends on the honey bee inside a stable colony. Thus, comparison of the genome and transcriptome sequences with those of a tick and free-living mites has revealed the specific features of the genome shaped by interaction with the honey bee and colony environment. Genome and transcriptome sequences of T. mercedesae, as well as Varroa destructor (another globally prevalent ectoparasitic mite of honey bee), not only provide insights into the mite biology, but may also help to develop measures to control the most serious pests of the honey bee. © The Author 2017. Published by Oxford University Press.

Occurrence and seasonal prevalence of the coconut mite, Aceria guerreronis (Eriophyidae), and associated arthropods in Oman.

PubMed

Al-Shanfari, Abdulaziz; Hountondji, Fabien C C; Al-Zawamri, Hamid; Rawas, Hassan; Al-Mashiki, Yussef; de Moraes, Gilberto J; Moore, Dave; Gowen, Simon R

2013-06-01

The coconut palm is an important crop in the sub arid coastal plain of Dhofar, Oman, for the high demand for its nut water and its use as ornamental plant. Damage of coconut fruits by the eriophyid mite Aceria guerreronis Keifer was first reported in that region in the late 1980s, but background information about the ecology of the pest in Oman was missing. Four surveys were conducted in different seasons from 2008 to 2009, to assess the distribution and prevalence of the coconut mite and its damage as well as the presence of natural enemies. Infestation by the coconut mite was conspicuous on most (99.7 %) palm trees, with 82.5 % damaged fruits. The average (± SE) density of coconut mites per fruit was 750 ± 56; this level of infestation led to the incidence of over 25 % of surface damage on more than half of the fruits. The mite appeared more abundant at the end of the cold season through the summer. No significant differences were observed between infestation levels on local varieties, hybrids and on dwarf varieties. Neoseiulus paspalivorus (De Leon), Cydnoseius negevi (Swirski & Amitai) and Amblyseius largoensis (Muma) were the predatory mites found under the bracts of over 30 % of the coconut fruits and on 68 % of the coconut trees. Considering all sampling dates and all varieties together, average (± SE) phytoseiid density was 1.4 ± 1.19 per fruit. Other mites found in the same habitat as A. guerreronis included the tarsonemids Steneotarsonemus furcatus De Leon and Nasutitarsonemus omani Lofego & Moraes. The pathogenic fungus Hirsutella thompsonii Fisher was rarely found infecting the coconut mite in Dhofar. Other fungal pathogens, namely Cordyceps sp. and Simplicillium sp., were more prevalent.

Interspecific interactions explain variation in the duration of paternal care in the burying beetle

PubMed Central

De Gasperin, Ornela; Duarte, Ana; Kilner, Rebecca M.

2015-01-01

Why is there so much variation within species in the extent to which males contribute to offspring care? Answers to this question commonly focus on intraspecific sources of variation in the relative costs and benefits of supplying paternal investment. With experiments in the laboratory on the burying beetle, Nicrophorus vespilloides, and its phoretic mite Poecilochirus carabi, we investigated whether interactions with a second species might also account for intraspecific variation in the extent of paternal care, and whether this variation is due to adaptation or constraint. In our first experiment we bred beetles in the presence or absence of phoretic mites, using a breeding box that mimicked natural conditions by allowing parents to leave the breeding attempt at a time of their choosing. We found that males abandoned their brood sooner when breeding alongside mites than when breeding in their absence. Female patterns of care were unchanged by the mites. Nevertheless, in this experiment, no correlates of beetle fitness were affected by the presence of the mites during reproduction (neither paternal life span after reproduction nor brood size or average larval mass). In a second experiment, we again bred beetles with or without mites but this time we prevented parents from abandoning the brood. This time we found that both parents and the brood suffered fitness costs when breeding alongside mites, compared with families breeding in the absence of mites. We conclude that males adaptively reduce their contributions to care when mites are present, so as to defend their offspring's fitness and their own residual fitness. Interspecific interactions thus account for intraspecific variation in the duration of paternal care. PMID:26778845

Light and scanning electron microscopic studies of Unionicola tetrafurcatus (Acari: Unionicolidae) infecting four freshwater bivalve species with referring to histopathological effect on its hosts.

PubMed

Abdel-Gaber, Rewaida; Fol, Mona; Al Quraishy, Saleh

2018-05-08

Water mites of the genus Unionicola are the most common symbionts of freshwater bivalves. During the current investigation, a total of 120 live freshwater mussels [Corbicula fluminea (Veneroida), Coelatura aegyptiaca (Unionoidea) Mutela rostrata and Chambardia rubens (Mutelidae)], were collected from 2 localities in Tura (Helwan Governorate) and El Kanater (Qaluobiya Governorate), Egypt. Only 3 of the 4 bivalve species listed are considered freshwater bivalves (members of Unionoidea). While, C. fluminea belong to the family Cyrenidae within Veneroida. The collected mussels were dissected and examined for the presence of unionicolid mites. It was found that 30.83% (37/120) were infected with a single mite species Unionicola tetrafurcatus (Unionicolidae). The highest prevalence was observed during the summer with 83.33% (25/30), whereas the least was observed in autumn, i.e. 33.33% (10/30). Mites were recovered from the gills, gonads, and visceral mass of mussel hosts. gills of host mussels were the primary site of oviposition for unionicola mites. Smaller bivalves in size had significantly greater numbers of mites than larger ones in size. Numbers of mites per host species was variable and the highest prevalence level of 83.33% (25/30) was recorded in C. fluminea, while, the lowest one of 16.66% (5/30) was found in C. rubens. Morphological and morphometric characterizations of mites revealed some differences between the present species and other related Unionicola. Histopathological responses of host mussels to the eggs, larvae, and cuticular remnants of U. tetrafurcatus were also studied. Therefore, the present study demonstrated that freshwater bivalves have a new host and locality records for infection with U. tetrafurcatus. Future studies are recommended to include advanced molecular characteristics for these mites.

Behaviour of coconut mites preceding take-off to passive aerial dispersal.

PubMed

Melo, J W S; Lima, D B; Sabelis, M W; Pallini, A; Gondim, M G C

2014-12-01

For more than three decades the coconut mite Aceria guerreronis Keifer is one of the most important pests of coconut palms and has recently spread to many coconut production areas worldwide. Colonization of coconut palms is thought to arise from mites dispersing aerially after take-off from other plants within the same plantation or other plantations. The underlying dispersal behaviour of the mite at take-off, in the airborne state and after landing is largely unknown and this is essential to understand how they spread from tree to tree. In this article we studied whether take-off to aerial dispersal of coconut mites is preceded by characteristic behaviour, whether there is a correlation between the body position preceding aerial dispersal and the direction of the wind, and whether the substrate (outer surface of coconut bracts or epidermis) and the wind speed matter to the decision to take-off. We found that take-off can sometimes be preceded by a raised body stance, but more frequently take-off occurs while the mite is walking or resting on its substrate. Coconut mites that become airborne assumed a body stance that had no relation to the wind direction. Take-off was suppressed on a substrate providing food to coconut mites, but occurred significantly more frequently on the outer surface of coconut bracts than on the surface of the fruit. For both substrates, take-off frequency increased with wind speed. We conclude that coconut mites have at least some degree of control over take-off for aerial dispersal and that there is as yet no reason to infer that a raised body stance is necessary to become airborne.

Genetic variation in jasmonic acid- and spider mite-induced plant volatile emission of cucumber accessions and attraction of the predator Phytoseiulus persimilis.

PubMed

Kappers, Iris F; Verstappen, Francel W A; Luckerhoff, Ludo L P; Bouwmeester, Harro J; Dicke, Marcel

2010-05-01

Cucumber plants (Cucumis sativus L.) respond to spider-mite (Tetranychus urticae) damage with the release of specific volatiles that are exploited by predatory mites, the natural enemies of the spider mites, to locate their prey. The production of volatiles also can be induced by exposing plants to the plant hormone jasmonic acid. We analyzed volatile emissions from 15 cucumber accessions upon herbivory by spider mites and upon exposure to jasmonic acid using gas chromatography-mass spectrometry. Upon induction, cucumber plants emitted over 24 different compounds, and the blend of induced volatiles consisted predominantly of terpenoids. The total amount of volatiles was higher in plants treated with jasmonic acid than in those infested with spider mites, with (E)-4,8-dimethyl-1,3,7-nonatriene, (E,E)-alpha-farnesene, and (E)-beta-ocimene as the most abundant compounds in all accessions in both treatments. Significant variation among the accessions was found for the 24 major volatile compounds. The accessions differed strongly in total amount of volatiles emitted, and displayed very different odor profiles. Principal component analysis performed on the relative quantities of particular compounds within the blend revealed clusters of highly correlated volatiles, which is suggestive of common metabolic pathways. A number of cucumber accessions also were tested for their attractiveness to Phytoseiulus persimilis, a specialist predator of spider mites. Differences in the attraction of predatory mites by the various accessions correlated to differences in the individual chemical profiles of these accessions. The presence of genetic variation in induced plant volatile emission in cucumber shows that it is possible to breed for cucumber varieties that are more attractive to predatory mites and other biological control agents.

Genetic Variation in Jasmonic Acid- and Spider Mite-Induced Plant Volatile Emission of Cucumber Accessions and Attraction of the Predator Phytoseiulus persimilis

PubMed Central

Verstappen, Francel W. A.; Luckerhoff, Ludo L. P.; Bouwmeester, Harro J.; Dicke, Marcel

2010-01-01

Cucumber plants (Cucumis sativus L.) respond to spider–mite (Tetranychus urticae) damage with the release of specific volatiles that are exploited by predatory mites, the natural enemies of the spider mites, to locate their prey. The production of volatiles also can be induced by exposing plants to the plant hormone jasmonic acid. We analyzed volatile emissions from 15 cucumber accessions upon herbivory by spider mites and upon exposure to jasmonic acid using gas chromatography—mass spectrometry. Upon induction, cucumber plants emitted over 24 different compounds, and the blend of induced volatiles consisted predominantly of terpenoids. The total amount of volatiles was higher in plants treated with jasmonic acid than in those infested with spider mites, with (E)-4,8-dimethyl-1,3,7-nonatriene, (E,E)-α-farnesene, and (E)-β-ocimene as the most abundant compounds in all accessions in both treatments. Significant variation among the accessions was found for the 24 major volatile compounds. The accessions differed strongly in total amount of volatiles emitted, and displayed very different odor profiles. Principal component analysis performed on the relative quantities of particular compounds within the blend revealed clusters of highly correlated volatiles, which is suggestive of common metabolic pathways. A number of cucumber accessions also were tested for their attractiveness to Phytoseiulus persimilis, a specialist predator of spider mites. Differences in the attraction of predatory mites by the various accessions correlated to differences in the individual chemical profiles of these accessions. The presence of genetic variation in induced plant volatile emission in cucumber shows that it is possible to breed for cucumber varieties that are more attractive to predatory mites and other biological control agents. PMID:20383796

Preference of red mite Tetranychus ludeni Zacher (Acari: Tetranychidae) to sweet potato genotypes.

PubMed

Castro, B M C; Soares, M A; Andrade Júnior, V C; Santos Júnior, V C; Fontes, P C R; Wilcken, C F; Serrão, J E; Zanuncio, J C

2018-06-21

Tetranychus ludeni damages the sweet potato. Pest development can vary between plant genotypes. The objective was to identify the preference of Tetranychus ludeni for Ipomoea batatas genotypes, from the germplasm bank at the Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM). Natural infestations of this mite were observed on 54 sweet potato genotypes in potted, in a greenhouse. Three mite-infested leafs of each genotype were collected and analyzed. The red mite showed different population density rate in genotypes. The BD 29 genotype was found to be highly susceptible, the BD 08, BD 57, BD 17 and Espanhola genotypes were moderately susceptible, and the others forty-nine genotypes showed low susceptibility to the mite.

Efficacy and safety of sarolaner against generalized demodicosis in dogs in European countries: a non-inferiority study.

PubMed

Becskei, Csilla; Cuppens, Otto; Mahabir, Sean P

2018-06-01

Treatment of canine demodicosis can be challenging; new treatments are always being sought. The efficacy of sarolaner was evaluated in comparison with a moxidectin/imidacloprid topical product against generalized demodicosis in dogs in a randomized, single-masked, multi-centre field study. Client-owned dogs were treated monthly with oral sarolaner (n = 53) or with weekly/monthly topical moxidectin/imidacloprid (n = 28). Mites were counted monthly in deep skin scrapings and the severity of skin lesions was evaluated. Dogs completed the study when no live mites were found on two consecutive monthly skin scrapings or on day 180 at the latest (study end). Parasitological cure, defined as the first time that no live mites were found in the skin scrapings, was achieved in 92.9% and 100% of the dogs after three and no more than five monthly treatments with sarolaner (respectively). In the moxidectin/imidacloprid group, 77.3% and 91.7% of the dogs were cured after three and six months, respectively. Parasitological cure rate for sarolaner was non-inferior to moxidectin/imidacloprid on day 60. Mite counts were reduced by 77.2%, 95.0%, 98.5%, 99.0%, 100% and 100% in the sarolaner group and by 68.0%, 88.4%, 91.1%, 92.7%, 73.9% and 82.2% in the moxidectin/imidacloprid group, on days 30, 60, 90, 120, 150 and 180, respectively, compared to pre-treatment counts. The skin lesions improved throughout the study; the total affected body surface decreased by 94% in the sarolaner and by 72% in the moxidectin/imidacloprid group. There were no treatment-related adverse events. Monthly oral administration of sarolaner was safe and highly effective in the treatment of generalized demodicosis in dogs. © 2018 The Authors. Veterinary Dermatology published by John Wiley & Sons Ltd on behalf of the ESVD and ACVD.

Next generation sequencing of Apis mellifera syriaca identifies genes for Varroa resistance and beneficial bee keeping traits.

PubMed

Haddad, Nizar; Mahmud Batainh, Ahmed; Suleiman Migdadi, Osama; Saini, Deepti; Krishnamurthy, Venkatesh; Parameswaran, Sriram; Alhamuri, Zaid

2016-08-01

Apis mellifera syriaca exhibits a high degree of tolerance to pests and pathogens including varroa mites. This native honey bee subspecies of Jordan expresses behavioral adaptations to high temperature and dry seasons typical of the region. However, persistent honey bee imports of commercial breeder lines are endangering local honey bee population. This study reports the use of next-generation sequencing (NGS) technology to study the A. m. syriaca genome and to identify genetic factors possibly contributing toward mite resistance and other favorable traits. We obtained a total of 46.2 million raw reads by applying the NGS to sequence A. m. syriaca and used extensive bioinformatics approach to identify several candidate genes for Varroa mite resistance, behavioral and immune responses characteristic for these bees. As a part of characterizing the functional regulation of molecular genetic pathway, we have mapped the pathway genes potentially involved using information from Drosophila melanogaster and present possible functional changes implicated in responses to Varroa destructor mite infestation toward this. We performed in-depth functional annotation methods to identify ∼600 candidates that are relevant, genes involved in pathways such as microbial recognition and phagocytosis, peptidoglycan recognition protein family, Gram negative binding protein family, phagocytosis receptors, serpins, Toll signaling pathway, Imd pathway, Tnf, JAK-STAT and MAPK pathway, heamatopioesis and cellular response pathways, antiviral, RNAi pathway, stress factors, etc. were selected. Finally, we have cataloged function-specific polymorphisms between A. mellifera and A. m. syriaca that could give better understanding of varroa mite resistance mechanisms and assist in breeding. We have identified immune related embryonic development (Cactus, Relish, dorsal, Ank2, baz), Varroa hygiene (NorpA2, Zasp, LanA, gasp, impl3) and Varroa resistance (Pug, pcmt, elk, elf3-s10, Dscam2, Dhc64C, gro, futsch) functional variations genes between A. mellifera and A. m. syriaca that could be used to develop an effective molecular tool for bee conservation and breeding programs to improve locally adapted strains such as syriaca and utilize their advantageous traits for the benefit of apiculture industry. © 2015 Institute of Zoology, Chinese Academy of Sciences.

Ecology, life history and management of tropilaelaps mites

USDA-ARS?s Scientific Manuscript database

Parasitic mites are the major threat of the Western honey bee, Apis mellifera. For much of the world, Varroa destructor single-handedly inflicts unsurmountable problems to A. mellifera beekeeping. However, A. mellifera in Asia is also faced with another genus of destructive parasitic mite, Tropilae...

Lignin-encapsulated nootkatone as a potential biomiticide

USDA-ARS?s Scientific Manuscript database

Herbivorous mites are recurrent problems in woody ornamental production and landscape settings. Mites cause damage to leaf tissue through their feeding behavior, salivary excretions and, in the case of spider mites, silk webbing they leave behind. Botanical-based miticides, such as neem oil, are use...

Preparing soft-bodied arthropods for arthropods for microscope examination: Mites (Arachnida: Acari)

USDA-ARS?s Scientific Manuscript database

Proper identification of mites (Arachnida: Acari) require preparation of the specimen on a microscope slide. This training video provides visual instruction on how to prepare mite specimens on microscope slides for examination and identification. Steps ranging from collection, specimen clearing, use...

Varroa destructor Mites Can Nimbly Climb from Flowers onto Foraging Honey Bees

PubMed Central

Smith, Michael L.; Seeley, Thomas D.

2016-01-01

Varroa destructor, the introduced parasite of European honey bees associated with massive colony deaths, spreads readily through populations of honey bee colonies, both managed colonies living crowded together in apiaries and wild colonies living widely dispersed in natural settings. Mites are hypothesized to spread between most managed colonies via phoretically riding forager bees when they engage in robbing colonies or they drift between hives. However, widely spaced wild colonies show Varroa infestation despite limited opportunities for robbing and little or no drifting of bees between colonies. Both wild and managed colonies may also exchange mites via another mechanism that has received remarkably little attention or study: floral transmission. The present study tested the ability of mites to infest foragers at feeders or flowers. We show that Varroa destructor mites are highly capable of phoretically infesting foraging honey bees, detail the mechanisms and maneuvers by which they do so, and describe mite behaviors post-infestation. PMID:27942015

Bioelimination of /sup 51/Cr and /sup 85/Sr by cockroaches, Gromphadorhina portentosa (orthoptera: blaberidae), as affected by mites, Gromphadorholaelaps schaeferi (parasitiformes: laelapidae)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schowalter, T.D.; Crossley, D.A. Jr.

1982-03-01

The rates of Chromium-51 and Strontium-85 assimilation and bioelimination by the hissing cockroach, Gromphadorhina portentosa (Schaum) are described when the symbiotic mite, Gromphadorholaelaps schaeferi Till, was present or removed. Mite-infested cockroaches had significantly higher rates of /sup 51/Cr elimination relative to mite-free cockroaches, implying more rapid gut clearance times. The authors did not find a significant mite effect on /sup 85/Sr elimination by the host, but mite effects could have been masked by the apparently unique process of nutrient assimilation and elimination by G. portentosa. Conventional models of radioactive tracer bioelimination predict a rapid initial loss of tracer due tomore » gut clearance, followed by a slower loss due to excretion of assimilated tracer. The results indicated that assimilated /sup 85/Sr was eliminated earlier than unassimilated /sup 85/Sr, which was lost by defecation.« less

Prevalence and clinical characteristics of adult-onset atopic dermatitis with positive skin prick testing to mites.

PubMed

Kulthanan, Kanokvalai; Chularojanamontri, Leena; Manapajon, Araya; Nuchkull, Piyavadee

2011-12-01

The clinical role of house dust mite (HDM) in atopic dermatitis (AD) is still controversial. The aim of the study is to assess the prevalence, clinical relevance and characteristics of adult-onset AD patients with positive skin prick tests (SPT) to mites. The case record forms of adult-onset AD patients who underwent SPT at the Skin Allergy Clinic, Siriraj Hospital were reviewed. Forty-one of 62 patients (66.1%) had positive SPT to mites. The frequency of intrinsic AD among adult-onset AD was 4.8% (3/62). SPT to HDM tended to be positive in patients who had personal or family history of atopy, positive SPT to several specific antigens or who presented with elevated serum IgE, chelitis, recurrent conjunctivitis and perifollicular accentuation, respectively. CONCLUSION The prevalence of adult-onset AD patients with mite sensitivity was high. There were some notable features that tended to be present in mite sensitive adult-onset AD patients.

Intercropping With Fruit Trees Increases Population Abundance and Alters Species Composition of Spider Mites on Cotton.

PubMed

Li, Haiqiang; Pan, Hongsheng; Wang, Dongmei; Liu, Bing; Liu, Jian; Zhang, Jianping; Lu, Yanhui

2018-05-05

With the recent increase in planting of fruit trees in southern Xinjiang, the intercropping of fruit trees and cotton has been widely adopted. From 2014 to 2016, a large-scale study was conducted in Aksu, an important agricultural area in southern Xinjiang, to compare the abundance and species composition of spider mites in cotton fields under jujube-cotton, apple-cotton, and cotton monocrop systems. The abundance of spider mites in cotton fields under both intercropping systems was generally higher than in the cotton monocrop. The species composition of spider mites also differed greatly between cotton intercropped with apple or jujube compared to the cotton monocrop. The relative proportion of Tetranychus truncates Ehara (Acari: Tetranychidae) in the species complex generally increased while that of another spider mite, Tetranychus dunhuangensis Wang (Acari: Tetranychidae), decreased under fruit tree-cotton systems. More attention should be paid to the monitoring and management of spider mites, especially T. truncates in this important region of China.

Deformed wing virus implicated in overwintering honeybee colony losses.

PubMed

Highfield, Andrea C; El Nagar, Aliya; Mackinder, Luke C M; Noël, Laure M-L J; Hall, Matthew J; Martin, Stephen J; Schroeder, Declan C

2009-11-01

The worldwide decline in honeybee colonies during the past 50 years has often been linked to the spread of the parasitic mite Varroa destructor and its interaction with certain honeybee viruses. Recently in the United States, dramatic honeybee losses (colony collapse disorder) have been reported; however, there remains no clear explanation for these colony losses, with parasitic mites, viruses, bacteria, and fungal diseases all being proposed as possible candidates. Common characteristics that most failing colonies share is a lack of overt disease symptoms and the disappearance of workers from what appears to be normally functioning colonies. In this study, we used quantitative PCR to monitor the presence of three honeybee viruses, deformed wing virus (DWV), acute bee paralysis virus (ABPV), and black queen cell virus (BQCV), during a 1-year period in 15 asymptomatic, varroa mite-positive honeybee colonies in Southern England, and 3 asymptomatic colonies confirmed to be varroa mite free. All colonies with varroa mites underwent control treatments to ensure that mite populations remained low throughout the study. Despite this, multiple virus infections were detected, yet a significant correlation was observed only between DWV viral load and overwintering colony losses. The long-held view has been that DWV is relatively harmless to the overall health status of honeybee colonies unless it is in association with severe varroa mite infestations. Our findings suggest that DWV can potentially act independently of varroa mites to bring about colony losses. Therefore, DWV may be a major factor in overwintering colony losses.

Analysis of ectoparasites (chigger mites, gamasid mites, fleas and sucking lice) of the Yunnan red-backed vole (Eothenomys miletus) sampled throughout its range in southwest China.

PubMed

Peng, P-Y; Guo, X-G; Song, W-Y; Hou, P; Zou, Y-J; Fan, R; He, X-S

2015-12-01

The Yunnan red-backed vole Eothenomys miletus (Rodentia: Cricetidae) is an endemic rodent species and reservoir host of zoonoses in southwest China. Based on a large host sample (2463 voles collected from 39 localities between 2001 and 2013), a general analysis of four categories of ectoparasite (fleas, sucking lice, chigger mites and gamasid mites) on E. miletus across its entire range of distribution was made. This analysis identified a total of 71 895 ectoparasites belonging to 320 species (30 species of flea, 9 of sucking louse, 106 of gamasid mite and 175 of chigger mite) with a high prevalence (87%), mean abundance (29.19) and mean intensity (33.69). Of the 18 vector species of zoonoses found on E. miletus, the flea Ctenophthalmus quadratus (Siphonaptera: Hystrichopsyllidae) and chigger mite Leptotrombidium scutellare (Trombidiformes: Trombiculidae) were the dominant species; these are the main vectors of zoonoses in China. All of the dominant parasite species showed an aggregated distribution pattern. Male voles harboured more species of parasite than females. Chigger mites represented the most abundant species group on voles and their prevalence was positively correlated with mean abundance (r = 0.73; P < 0.05). As a single rodent species, E. miletus has a high potential to harbour abundant ectoparasites with high species diversity and high rates of infestation. The sex of the vole affects ectoparasite infestation. © 2015 The Royal Entomological Society.

Increased Tolerance and Resistance to Virus Infections: A Possible Factor in the Survival of Varroa destructor-Resistant Honey Bees (Apis mellifera)

PubMed Central

Locke, Barbara; Forsgren, Eva; de Miranda, Joachim R.

2014-01-01

The honey bee ectoparasitic mite, Varroa destructor, has a world-wide distribution and inflicts more damage than all other known apicultural diseases. However, Varroa-induced colony mortality is more accurately a result of secondary virus infections vectored by the mite. This means that honey bee resistance to Varroa may include resistance or tolerance to virus infections. The aim of this study was to see if this is the case for a unique population of mite-resistant (MR) European honey bees on the island of Gotland, Sweden. This population has survived uncontrolled mite infestation for over a decade, developing specific mite-related resistance traits to do so. Using RT-qPCR techniques, we monitored late season virus infections, Varroa mite infestation and honey bee colony population dynamics in the Gotland MR population and compared this to mite-susceptible (MS) colonies in a close by apiary. From summer to autumn the deformed wing virus (DWV) titres increased similarly between the MR and MS populations, while the black queen cell virus (BQCV) and sacbrood virus (SBV) titres decreased substantially in the MR population compared to the MS population by several orders of magnitude. The MR colonies all survived the following winter with high mite infestation, high DWV infection, small colony size and low proportions of autumn brood, while the MS colonies all perished. Possible explanations for these changes in virus titres and their relevance to Varroa resistance and colony winter survival are discussed. PMID:24926792

Field application of menthol for Japanese honey bees, Apis cerana japonica (Hymenoptera: Apidae), to control tracheal mites, Acarapis woodi (Acari: Tarsonemidae).

PubMed

Maeda, Taro; Sakamoto, Yoshiko

2016-11-01

The first record of tracheal mites, Acarapis woodi, in Japan was made in 2010. These mites have since caused serious damage to the colonies of Japanese honey bees, Apis cerana japonica. In the present study, to control the mites on Japanese honey bees with l-menthol, an agent used for European honey bees, Apis mellifera, we investigated (1) the seasonality of menthol efficacy, (2) the overwintering mortality of menthol-treated colonies, and (3) the menthol residue in honey under field conditions in cooperation with private beekeepers of Japanese honey bees. Seasonal menthol efficacy was tested by applying 30 g of l-menthol for 1 month in different seasons. Mite prevalence was measured by dissecting the honey bee thorax. Overwintering mortality was monitored during winter after checking the mite prevalence in autumn, and was compared with that of untreated colonies reported in our previous study. The residual level of menthol in honey was measured by GC-MS. The results showed that the menthol-treated colonies had a smaller rate of increase in mite prevalence than the untreated colonies. The effects of menthol were highest in March and April. The winter mortality was depressed by menthol treatment. Honey samples extracted from the menthol-treated colonies included 0.4 ppm of menthol residue on average. Our findings suggest that menthol treatment is effective for controlling the tracheal mites on Japanese honey bees.

Compatibility of spinosad with predaceous mites (Acari) used to control Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae).

PubMed

Rahman, Touhidur; Spafford, Helen; Broughton, Sonya

2011-08-01

Spinosad is a biopesticide widely used for control of Frankliniella occidentalis (Pergande). It is reported to be non-toxic to several predatory mite species used for the biological control of thrips. Predatory mites Typhlodromips montdorensis (Schicha), Neoseiulus cucumeris (Oudemans) and Hypoaspis miles (Berlese) have been used for control of F. occidentalis. This study investigated the impact of direct and residual toxicity of spinosad on F. occidentalis and predatory mites. The repellency of spinosad residues to these predatory mites was also investigated. Direct contact to spinosad effectively reduced the number of F. occidentalis adults and larvae, causing > 96% mortality. Spinosad residues aged 2-96 h were also toxic to F. occidentalis. Direct exposure to spinosad resulted in > 90% mortality of all three mite species. Thresholds for the residual toxicity (contact) of spinosad (LT25 ) were estimated as 4.2, 3.2 and 5.8 days for T. montdorensis, N. cucumeris and H. miles respectively. When mites were simultaneously exposed to spinosad residues and fed spinosad-intoxicated thrips larvae, toxicity increased. Residual thresholds were re-estimated as 5.4, 3.9 and 6.1 days for T. montdorensis, N. cucumeris and H. miles respectively. Residues aged 2-48 h repelled T. montdorensis and H. miles, and residues aged 2-24 h repelled N. cucumeris. Predatory mites can be safely released 6 days after spinosad is applied for the management of F. occidentalis. Copyright © 2011 Society of Chemical Industry.

Repellent activity of desiccant dusts and conidia of the entomopathogenic fungus Beauveria bassiana when tested against poultry red mites (Dermanyssus gallinae) in laboratory experiments.

PubMed

Kilpinen, Ole; Steenberg, Tove

2016-11-01

Desiccant dusts and entomopathogenic fungi have previously been found to hold potential against the poultry red mite, which is an important pest in egg production and notoriously difficult to control. Both control agents may cause repellence in other arthropods and potentially also influence control levels adversely when used against the poultry red mite. Five desiccant dust products with good efficacy against the poultry red mite Dermanyssus gallinae caused avoidance behavior in mites when tested in bioassays. The repellent activity was correlated with efficacy, which was found to depend on both dose and relative humidity (RH). However, one desiccant dust was significantly less repellent compared to other dusts with similar levels of efficacy. Further, dry conidia of the fungus Beauveria bassiana were also shown to be repellent to poultry red mites, both when applied on its own and when admixed with a low dose of the desiccant dust Diamol. The pick-up of desiccant dust particles and fungus conidia from treated surfaces by mites did not differ depending on RH, whereas the overall efficacy of the two control agents were significantly higher at 75 than at 85 % RH. In addition, the combined effect of the two substances was synergistic when tested in a bioassay where mites could choose whether to cross a treated surface. This is the first time a member of Acari has been shown to be repelled by desiccant dusts and by conidia of an entomopathogenic fungus.

Whiteflies interfere with indirect plant defense against spider mites in Lima bean

PubMed Central

Zhang, Peng-Jun; Zheng, Si-Jun; van Loon, Joop J. A.; Boland, Wilhelm; David, Anja; Mumm, Roland; Dicke, Marcel

2009-01-01

Plants under herbivore attack are able to initiate indirect defense by synthesizing and releasing complex blends of volatiles that attract natural enemies of the herbivore. However, little is known about how plants respond to infestation by multiple herbivores, particularly if these belong to different feeding guilds. Here, we report the interference by a phloem-feeding insect, the whitefly Bemisia tabaci, with indirect plant defenses induced by spider mites (Tetranychus urticae) in Lima bean (Phaseolus lunatus) plants. Additional whitefly infestation of spider-mite infested plants resulted in a reduced attraction of predatory mites (Phytoseiulus persimilis) compared to attraction to plants infested by spider mites only. This interference is shown to result from the reduction in (E)-β-ocimene emission from plants infested by both spider mites and whiteflies. When using exogenous salicylic acid (SA) application to mimic B. tabaci infestation, we observed similar results in behavioral and chemical analyses. Phytohormone and gene-expression analyses revealed that B. tabaci infestation, as well as SA application, inhibited spider mite-induced jasmonic acid (JA) production and reduced the expression of two JA-regulated genes, one of which encodes for the P. lunatus enzyme β-ocimene synthase that catalyzes the synthesis of (E)-β-ocimene. Remarkably, B. tabaci infestation concurrently inhibited SA production induced by spider mites. We therefore conclude that in dual-infested Lima bean plants the suppression of the JA signaling pathway by whitefly feeding is not due to enhanced SA levels. PMID:19965373

Evaluating Vaccine Candidates for Filariasis

DTIC Science & Technology

2013-04-16

rat mite (Ornithonyssus bacoti). The infective larvae migrate through the host dermis and subcutaneous tissue until contacting host lymphatic channels...Derivative O. volvulus Associated with arachidonic acid pathway and requires iNOS Dermatitis in response to rapid death of MF in the skin M

77 FR 26004 - Issuance of an Experimental Use Permit

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-02

... the use of 2,500 pounds of the insecticide etoxazole on up to 20,000 acres of field corn, pop corn or corn grown for seed to evaluate the control of mites over larger scale and commercial plots. The...

NEGLECTED COMPONENTS OF BIODIVERSITY: SOIL ORIBATID MITES, COMMUNITY STRUCTURE AND SOIL RECOVERY

EPA Science Inventory

Oribatid mites are an abundant and diverse component of soils in regional pine forests, and are valuable in characterizing the biodiversity of these forested lands. We sampled oribatid mites using soil cores and leaf litterbags, in young aggrading forest stands. Comparing these...

Th2 polarization by Der p 1--pulsed monocyte-derived dendritic cells is due to the allergic status of the donors.

PubMed

Hammad, H; Charbonnier, A S; Duez, C; Jacquet, A; Stewart, G A; Tonnel, A B; Pestel, J

2001-08-15

The polarization of the immune response toward a Th2 or a Th1 profile can be mediated by dendritic cells (DCs) following antigen presentation and interaction with T cells. Costimulatory molecules such as CD80 and CD86 expressed by DCs, the polarizing cytokine environment during DC--T-cell interaction, and also the nature of the antigen are critical in the orientation of the immune response. In this study, the effect of the cysteine protease Der p 1, one of the major allergens of the house dust mite Dermatophagoides pteronyssinus, on these different parameters was evaluated comparatively on monocyte-derived DCs obtained from healthy donors, from pollen-sensitive patients, or from patients sensitive to Dermatophagoides pteronyssinus. Results showed that Der p 1 induced an increase in CD86 expression only on DCs from house dust mite--sensitive patients. This was also associated with a higher capacity to induce T-cell proliferation, a rapid increase in the production of proinflammatory cytokines, tumor necrosis factor--alpha and interleukin (IL)-1 beta, and the type 2 cytokine IL-10. No changes in the release of IL-12 p70 were induced by Der p 1. Finally, purified T cells from house dust mite-sensitive patients stimulated by autologous Der p 1--pulsed DCs preferentially produced IL-4 rather than interferon-gamma. These effects were abolished in the presence of the inactive precursor of Der p 1 (ProDer p 1). Taken together, these data suggest that DCs from house dust mite--sensitive patients, in contrast to DCs from healthy donors and from pollen-sensitive patients, exposed to Der p 1 play a pivotal role in the enhancement of the Th2 response associated with the allergic reaction developed in response to house dust mite exposure. (Blood. 2001;98:1135-1141)

Phoretic mites and nematode associates of Scolytus multistraitus and Scolytus pygmaeus (Coleoptera: Scolytidae) in Austria

Treesearch

John C. Moser; Heino Konrad; Thomas Kirisits; Lynn K. Carta

2005-01-01

The species assemblages and abundance of phoretic mites and nematodes associated with the elm bark beetles, Scolytus multistriatus and Scolytus pygmaeus, were studied in Austria.A total of 3922 individual mites were recorded from 144 adults of S. multistriatus and 178...

[Gamasid mites (Gamasina) of rodents in the natural biotopes of Tchui Valley].

PubMed

Fedorova, S Zh; Tranbaev, Zh M

2005-01-01

The recent fauna of gamasid mites parasitising rodents in the natural biotopes of Tchui Valley (Kyrgyzstan) in investigated. 32 species of Gamasina are revealed, of which 9 are recorded in the region for the first time. A checklist of the gamasid mites is given.

The Tropilaelaps mites threat: Observations of their reproductive success

USDA-ARS?s Scientific Manuscript database

Tropilaelaps spp. are more successful parasitic mites of Apis mellifera than Varroa destructor in Asia (Burgett et al., Bee World 64:25-28). We sought explanations to this success by assessing their fecundity on European bees in three short experiments using the mite transfer technique: 1) fecundity...

Infestation of grasses by eriophyoid mites (Acari: Eriophyoidea) in Turkey

USDA-ARS?s Scientific Manuscript database

Despite the economic importance of eriophyoid mites as agricultural pests, especially of cereal crops, knowledge of the eriophyoid fauna in Turkey remains incomplete. This paper presents the results of a 3-year study on grass-infesting eriophyoid mites in Turkey. The aim of this study was to collect...

Is body size important? Seasonal changes in morphology in two grass-feeding Abacarus mites

USDA-ARS?s Scientific Manuscript database

Overwintering strategies in herbivorous mites (Acari: Eriophyoidea) are poorly understood. A study of two Abacarus spp., was conducted to compare body size parameters of adult females in different seasons. Mites of Abacarus n. sp. (under description) and A. lolli were sampled from Bromopsis inermis ...

Fine mapping for SNP markers associated with VSH behavior

USDA-ARS?s Scientific Manuscript database

Varroa Sensitive Hygiene (VSH) is a trait that effectively reduces varroa mite populations by removal of brood cells that contain primarily reproductive mites. Breeding for VSH has proven to be a successful control of mite populations in both pure VSH colonies as well as in out-crossed populations....

Trombiculiasis caused by chigger mites Eutrombicula (Acari: Trombiculidae) in Peruvian alpacas.

PubMed

Gomez-Puerta, Luis A; Olazabal, Juan; Lopez-Urbina, María T; Gonzalez, Armando E

2012-11-23

Trombiculiasis is an infestation caused by larvae members of the family Trombiculidae, common called chigger mites. In this study is presented the first case of trombiculiasis caused by the infestation of chigger mite Eutrombicula in alpacas from Peru. Twenty-two alpacas of a total of 130 animals were infested by Eutrombicula sp. The chigger mite location was only in the face skin folds and around the eyes. In addition, all alpacas infested had alopecia and dermatitis in the infected zone. Copyright © 2012 Elsevier B.V. All rights reserved.

Below-ground plant parts emit herbivore-induced volatiles: olfactory responses of a predatory mite to tulip bulbs infested by rust mites.

PubMed

Aratchige, N S; Lesna, I; Sabelis, M W

2004-01-01

Although odour-mediated interactions among plants, spider mites and predatory mites have been extensively studied above-ground, belowground studies are in their infancy. In this paper, we investigate whether feeding by rust mites (Aceria tulipae) cause tulip bulbs to produce odours that attract predatory mites (Neoseiulus cucumeris). Since our aim was to demonstrate such odours and not their relevance under soil conditions, the experiments were carried out using a classic Y-tube olfactometer in which the predators moved on a Y-shaped wire in open air. We found that food-deprived female predators can discriminate between odours from infested bulbs and odours from uninfested bulbs or artificially wounded bulbs. No significant difference in attractiveness to predators was found between clean bulbs and bulbs either wounded 30 min or 3 h before the experiment. These results indicate that it may not be simply the wounding of the bulbs, but rather the feeding by rust mites, which causes the bulb to release odours that attract N. cucumeris. Since bulbs are belowground plant structures, the olfactometer results demonstrate the potential for odour-mediated interactions in the soil. However, their importance in the actual soil medium remains to be demonstrated.

Characterization of the Copy Number and Variants of Deformed Wing Virus (DWV) in the Pairs of Honey Bee Pupa and Infesting Varroa destructor or Tropilaelaps mercedesae.

PubMed

Wu, Yunfei; Dong, Xiaofeng; Kadowaki, Tatsuhiko

2017-01-01

Recent honey bee colony losses, particularly during the winter, have been shown to be associated with the presence of both ectoparasitic mites and Deformed Wing Virus (DWV). Whilst the role of Varroa destructor mites as a viral vector is well established, the role of Tropilaelaps mercedesae mites in viral transmission has not been fully investigated. In this study, we tested the effects that V. destructor and T. mercedesae infestation have on fluctuation of the DWV copy number and alteration of the virus variants in honey bees by characterizing individual pupae and their infesting mites. We observed that both mite species were associated with increased viral copy number in honey bee pupae. We found a positive correlation between DWV copy number in pupae and copy number in infesting mites, and the same DWV type A variant was present in either low or high copy number in both honey bee pupae and infesting V. destructor . These data also suggest that variant diversity is similar between honey bee pupae and the mites that infest them. These results support a previously proposed hypothesis that DWV suppresses the honey bee immune system when virus copy number reaches a specific threshold, promoting greater replication.

Characterization of the Copy Number and Variants of Deformed Wing Virus (DWV) in the Pairs of Honey Bee Pupa and Infesting Varroa destructor or Tropilaelaps mercedesae

PubMed Central

Wu, Yunfei; Dong, Xiaofeng; Kadowaki, Tatsuhiko

2017-01-01

Recent honey bee colony losses, particularly during the winter, have been shown to be associated with the presence of both ectoparasitic mites and Deformed Wing Virus (DWV). Whilst the role of Varroa destructor mites as a viral vector is well established, the role of Tropilaelaps mercedesae mites in viral transmission has not been fully investigated. In this study, we tested the effects that V. destructor and T. mercedesae infestation have on fluctuation of the DWV copy number and alteration of the virus variants in honey bees by characterizing individual pupae and their infesting mites. We observed that both mite species were associated with increased viral copy number in honey bee pupae. We found a positive correlation between DWV copy number in pupae and copy number in infesting mites, and the same DWV type A variant was present in either low or high copy number in both honey bee pupae and infesting V. destructor. These data also suggest that variant diversity is similar between honey bee pupae and the mites that infest them. These results support a previously proposed hypothesis that DWV suppresses the honey bee immune system when virus copy number reaches a specific threshold, promoting greater replication. PMID:28878743

Sensitization of children in the Stockholm area to house dust mites.

PubMed

Nordvall, S L; Eriksson, M; Rylander, E; Schwartz, B

1988-09-01

Atopic sensitization of children in the Stockholm area to house dust mites (HDM) was investigated in a case-control study. Sixty children with and 60 without positive skin prick tests for HDM were matched for age and sex. HDM-sensitized children had previously more often lived in other areas known to be mite infested than the control children. Sensitization to mites was related to dampness in the homes, but no significant relationship was found to the type of residence, frequent visits to a summer house in the archipelago or parental smoking. Dust samples from mattresses of the children with the strongest positive reactions to mites in skin prick tests and the respective controls were subjected to an enzyme immunoassay, to measure the content of the major allergens of the Dermatophagoides (D.) species D. pterinyssinus, D. farinae and D. microceras. Mattress dust samples from the beds of HDM-sensitized children contained significantly higher HDM antigen concentrations than those from the beds of controls. Private houses contained significantly more HDM antigens than flats and 10 of 11 homes in which a dampness problem was recognized contained mite antigens. It is postulated that mite infestation is increasing in the area, energy-saving measures creating improved conditions for HDM survival.

Influence of environmental characteristics and climatic factors on mites in the dust of air-conditioner filters.

PubMed

Wu, J; Liu, Z G; Ran, P X; Wang, B

2009-12-01

To investigate mites in the dust of air-conditioner filters (MACF) in China, a total of 652 dust samples were collected from six cities: Guangzhou (n = 129), Nanchang (n = 127), Shanghai (n = 113), Xian (n = 93), Beijing (n = 93), and Shenyang (n = 79). Tarsonemus granarius was the most dominant species (87.2%). Dermatophagoides pteronyssinus and Dermatophagoides farinae only represented 7.0 and 3.0% of total mites, respectively. With latitude increasing, both mite occurrence rate (P < 0.001) and density (mites/g dust) (P < 0.001) were significantly decreasing. Multivariate regression analysis suggested that the annual average temperature and minimum temperature in different cities had dominant influences on MACF density. The logistic regression analysis revealed that the presence of MACF was positively associated with air-conditioner age, utilization time and power. Wall and window type air-conditioner had higher risk of finding MACF than the floor type air-conditioner. As far as the cleaning interval time of ACF was concerned, higher risk ratio and the highest density of MACF were found in the time stage of >3, < or =12 months. It was also suggested that house type could influence the presence of MACF. A negative association between the house floor and the MACF prevalence was found as well. Mites present in the dust of air-conditioner filters are potential indoor threat to asthma and allergy sufferers. In this study, we find that the storage mite Tarsonemus granarius is the predominant species of mites in the dust of air-conditioner filters (MACF). Thus, the possible clinical importance of T. granarius should cause more our attentions in the future. The abundance and distribution of MACF are also found significantly varied in different climatic regions of China. When we try to assess the possible risk of MACF, more attentions should be focused on subtropical region than temperate region. The influence analysis of environmental characteristics on the prevalence of MACF will shed light on the establishment of mite control strategy and the design of mite defense air-conditioner.

Gene-knockdown in the honey bee mite Varroa destructor by a non-invasive approach: studies on a glutathione S-transferase

PubMed Central

2010-01-01

Background The parasitic mite Varroa destructor is considered the major pest of the European honey bee (Apis mellifera) and responsible for declines in honey bee populations worldwide. Exploiting the full potential of gene sequences becoming available for V. destructor requires adaptation of modern molecular biology approaches to this non-model organism. Using a mu-class glutathione S-transferase (VdGST-mu1) as a candidate gene we investigated the feasibility of gene knockdown in V. destructor by double-stranded RNA-interference (dsRNAi). Results Intra-haemocoelic injection of dsRNA-VdGST-mu1 resulted in 97% reduction in VdGST-mu1 transcript levels 48 h post-injection compared to mites injected with a bolus of irrelevant dsRNA (LacZ). This gene suppression was maintained to, at least, 72 h. Total GST catalytic activity was reduced by 54% in VdGST-mu1 gene knockdown mites demonstrating the knockdown was effective at the translation step as well as the transcription steps. Although near total gene knockdown was achieved by intra-haemocoelic injection, only half of such treated mites survived this traumatic method of dsRNA administration and less invasive methods were assessed. V. destructor immersed overnight in 0.9% NaCl solution containing dsRNA exhibited excellent reduction in VdGST-mu1 transcript levels (87% compared to mites immersed in dsRNA-LacZ). Importantly, mites undergoing the immersion approach had greatly improved survival (75-80%) over 72 h, approaching that of mites not undergoing any treatment. Conclusions Our findings on V. destructor are the first report of gene knockdown in any mite species and demonstrate that the small size of such organisms is not a major impediment to applying gene knockdown approaches to the study of such parasitic pests. The immersion in dsRNA solution method provides an easy, inexpensive, relatively high throughput method of gene silencing suitable for studies in V. destructor, other small mites and immature stages of ticks. PMID:20712880

Severe ulceronecrotic dermatitis associated with mite infestation in the critically endangered Amargosa vole (Microtus californicus scirpensis).

PubMed

Foley, Janet; Branston, Tammy; Woods, Leslie; Clifford, Deana

2013-08-01

The entire range of the critically endangered Amargosa vole (Microtus californicus scirpensis) consists of less than 20 km(2) of riparian habitat in the Amargosa River drainage of the Mojave Desert in southern California. In September 2010, deformities on ears and chiggers on the ears and genitalia were detected, with some individuals so severely affected that they were missing ear pinnae altogether. Follow-up trapping was performed to document the presence of mites and mite-associated disease, and molecular characterization was performed on the mites. Of 151 Amargosa voles sampled from February to April of 2011, 60 (39.7%) voles had hard orange mites adhered to some part of their bodies, on ears of 46 (76.7%), on genitalia of 11 (18.3%), and near mammary tissue of 13 (21.7%) voles. Gross lesions were not detected on genitalia, but 47% of all individuals examined showed pinnal lesions and deformities, which included alopecia, swelling, marginal necrosis, and ulceration, as well as scarring, scabbing, and loss of pinna mass covering 25-100% of the pinnae. Biopsies revealed parakeratotic hyperkeratosis and acanthosis with diffuse neutrophilic exocytosis and dense necrotic granulocytes in the epidermis and superficial dermis associated with focal erosion and ulceration. In the underlying dermis, there were dense pleocellular inflammatory cell infiltrates composed primarily of necrotic granulocytes and multifocal hemorrhage. In some samples, mite mouthparts could be seen penetrating the superficial epidermis associated with focal necrosis, and mite fragments were found on the surface epidermis and within hair follicles. Microscopic examination of the mites documented that they were a larval trombiculid in the genus Neotrombicula with anatomical features that most closely resemble Neotrombicula microti, based on scutal shape, setation, and texture. PCR of 2 mite pools (each consisting of 3 mites from an individual animal) amplified 331 bp amplicons, which had 92-97% homology with the 18S rRNA gene of Leptotrombidium deliense, although coverage of Trombiculidae in GenBank is sparse. The severity and prevalence of lesions due to this chigger were atypical and distinct. Severe clinical trombiculiasis in this endangered species could negatively impact individual health and fitness.

Novel Scabies Mite Serpins Inhibit the Three Pathways of the Human Complement System

PubMed Central

Mika, Angela; Reynolds, Simone L.; Mohlin, Frida C.; Willis, Charlene; Swe, Pearl M.; Pickering, Darren A.; Halilovic, Vanja; Wijeyewickrema, Lakshmi C.; Pike, Robert N.; Blom, Anna M.; Kemp, David J.; Fischer, Katja

2012-01-01

Scabies is a parasitic infestation of the skin by the mite Sarcoptes scabiei that causes significant morbidity worldwide, in particular within socially disadvantaged populations. In order to identify mechanisms that enable the scabies mite to evade human immune defenses, we have studied molecules associated with proteolytic systems in the mite, including two novel scabies mite serine protease inhibitors (SMSs) of the serpin superfamily. Immunohistochemical studies revealed that within mite-infected human skin SMSB4 (54 kDa) and SMSB3 (47 kDa) were both localized in the mite gut and feces. Recombinant purified SMSB3 and SMSB4 did not inhibit mite serine and cysteine proteases, but did inhibit mammalian serine proteases, such as chymotrypsin, albeit inefficiently. Detailed functional analysis revealed that both serpins interfered with all three pathways of the human complement system at different stages of their activation. SMSB4 inhibited mostly the initial and progressing steps of the cascades, while SMSB3 showed the strongest effects at the C9 level in the terminal pathway. Additive effects of both serpins were shown at the C9 level in the lectin pathway. Both SMSs were able to interfere with complement factors without protease function. A range of binding assays showed direct binding between SMSB4 and seven complement proteins (C1, properdin, MBL, C4, C3, C6 and C8), while significant binding of SMSB3 occurred exclusively to complement factors without protease function (C4, C3, C8). Direct binding was observed between SMSB4 and the complement proteases C1s and C1r. However no complex formation was observed between either mite serpin and the complement serine proteases C1r, C1s, MASP-1, MASP-2 and MASP-3. No catalytic inhibition by either serpin was observed for any of these enzymes. In summary, the SMSs were acting at several levels mediating overall inhibition of the complement system and thus we propose that they may protect scabies mites from complement-mediated gut damage. PMID:22792350

Scabies mites alter the skin microbiome and promote growth of opportunistic pathogens in a porcine model.

PubMed

Swe, Pearl M; Zakrzewski, Martha; Kelly, Andrew; Krause, Lutz; Fischer, Katja

2014-01-01

The resident skin microbiota plays an important role in restricting pathogenic bacteria, thereby protecting the host. Scabies mites (Sarcoptes scabiei) are thought to promote bacterial infections by breaching the skin barrier and excreting molecules that inhibit host innate immune responses. Epidemiological studies in humans confirm increased incidence of impetigo, generally caused by Staphylococcus aureus and Streptococcus pyogenes, secondary to the epidermal infestation with the parasitic mite. It is therefore possible that mite infestation could alter the healthy skin microbiota making way for the opportunistic pathogens. A longitudinal study to test this hypothesis in humans is near impossible due to ethical reasons. In a porcine model we generated scabies infestations closely resembling the disease manifestation in humans and investigated the scabies associated changes in the skin microbiota over the course of a mite infestation. In a 21 week trial, skin scrapings were collected from pigs infected with S. scabies var. suis and scabies-free control animals. A total of 96 skin scrapings were collected before, during infection and after acaricide treatment, and analyzed by bacterial 16S rDNA tag-encoded FLX-titanium amplicon pyrosequencing. We found significant changes in the epidermal microbiota, in particular a dramatic increase in Staphylococcus correlating with the onset of mite infestation in animals challenged with scabies mites. This increase persisted beyond treatment from mite infection and healing of skin. Furthermore, the staphylococci population shifted from the commensal S. hominis on the healthy skin prior to scabies mite challenge to S. chromogenes, which is increasingly recognized as being pathogenic, coinciding with scabies infection in pigs. In contrast, all animals in the scabies-free cohort remained relatively free of Staphylococcus throughout the trial. This is the first experimental in vivo evidence supporting previous assumptions that establishment of pathogens follow scabies infection. Our findings provide an explanation for a biologically important aspect of the disease pathogenesis. The methods developed from this pig trial will serve as a guide to analyze human clinical samples. Studies building on this will offer implications for development of novel intervention strategies against the mites and the secondary infections.

Scabies Mites Alter the Skin Microbiome and Promote Growth of Opportunistic Pathogens in a Porcine Model

PubMed Central

Swe, Pearl M.; Zakrzewski, Martha; Kelly, Andrew; Krause, Lutz; Fischer, Katja

2014-01-01

Background The resident skin microbiota plays an important role in restricting pathogenic bacteria, thereby protecting the host. Scabies mites (Sarcoptes scabiei) are thought to promote bacterial infections by breaching the skin barrier and excreting molecules that inhibit host innate immune responses. Epidemiological studies in humans confirm increased incidence of impetigo, generally caused by Staphylococcus aureus and Streptococcus pyogenes, secondary to the epidermal infestation with the parasitic mite. It is therefore possible that mite infestation could alter the healthy skin microbiota making way for the opportunistic pathogens. A longitudinal study to test this hypothesis in humans is near impossible due to ethical reasons. In a porcine model we generated scabies infestations closely resembling the disease manifestation in humans and investigated the scabies associated changes in the skin microbiota over the course of a mite infestation. Methodology/Principal Findings In a 21 week trial, skin scrapings were collected from pigs infected with S. scabies var. suis and scabies-free control animals. A total of 96 skin scrapings were collected before, during infection and after acaricide treatment, and analyzed by bacterial 16S rDNA tag-encoded FLX-titanium amplicon pyrosequencing. We found significant changes in the epidermal microbiota, in particular a dramatic increase in Staphylococcus correlating with the onset of mite infestation in animals challenged with scabies mites. This increase persisted beyond treatment from mite infection and healing of skin. Furthermore, the staphylococci population shifted from the commensal S. hominis on the healthy skin prior to scabies mite challenge to S. chromogenes, which is increasingly recognized as being pathogenic, coinciding with scabies infection in pigs. In contrast, all animals in the scabies-free cohort remained relatively free of Staphylococcus throughout the trial. Conclusions/Significance This is the first experimental in vivo evidence supporting previous assumptions that establishment of pathogens follow scabies infection. Our findings provide an explanation for a biologically important aspect of the disease pathogenesis. The methods developed from this pig trial will serve as a guide to analyze human clinical samples. Studies building on this will offer implications for development of novel intervention strategies against the mites and the secondary infections. PMID:24875186

Higher-level molecular phylogeny of the water mites (Acariformes: Prostigmata: Parasitengonina: Hydrachnidiae).

PubMed

Dabert, Miroslawa; Proctor, Heather; Dabert, Jacek

2016-08-01

With nearly 6000 named species, water mites (Hydrachnidiae) represent the largest group of arachnids to have invaded and extensively diversified in freshwater habitats. Water mites together with three other lineages (the terrestrial Erythraiae and Trombidiae, and aquatic Stygothrombiae), make up the hyporder Parasitengonina, which is characterized by having parasitic larvae and predatory nymphs and adults. Relationships between the Hydrachnidiae and other members of the Parasitengonina are unclear, as are relationships among the major lineages of water mites. Monophyly of water mites has been asserted, with the possible exception of the morphologically distinctive Hydrovolzioidea. Here we infer the phylogeny of water mites using multiple molecular markers and including representatives of all superfamilies of Hydrachnidiae and of almost all other Parasitengonina. Our results support a monophyletic Parasitengonina including Trombidiae, Stygothrombiae, and Hydrachnidiae. A monophyletic Hydrachnidiae, including Hydrovolzioidea, is strongly supported. Terrestrial Parasitengonina do not form a monophyletic sister group to water mites. Stygothrombiae is close to water mites but is not nested within this clade. Water mites appear to be derived from ancestors close to Stygothrombiae or the erythraoid group Calyptostomatoidea; however, this relationship is not clear because of extremely short branches in this part of the parasitengonine tree. We recovered with strong support all commonly accepted water mite superfamilies except for Hydryphantoidea, which is clearly paraphyletic. Our data support the previously proposed clades Protohydrachnidia (Hydrovolzioidea and Eylaoidea), Euhydrachnidia (all remaining superfamilies), and the euhydrachnid subclade Neohydrachnidia (Lebertioidea, Hydrachnoidea, Hygrobatoidea, and Arrenuroidea). We found that larval leg structure and locomotory behavior are strongly congruent with the molecular phylogeny. Other morphological and behavioral characters, including host choice, are not as strongly correlated with phylogeny. Molecular dating suggests that the Hydrachnidiae arose about 235MYA, and that Neohydrachnidia began to diversify about 155MYA. Our results provide a strong framework for classification and for further elaboration at finer taxonomic scales, which will allow testing of ecological and behavioral hypotheses associated with the transition from terrestrial to aquatic life. Copyright © 2016 Elsevier Inc. All rights reserved.

Lower virus infections in Varroa destructor-infested and uninfested brood and adult honey bees (Apis mellifera) of a low mite population growth colony compared to a high mite population growth colony.

PubMed

Emsen, Berna; Hamiduzzaman, Mollah Md; Goodwin, Paul H; Guzman-Novoa, Ernesto

2015-01-01

A comparison was made of the prevalence and relative quantification of deformed wing virus (DWV), Israeli acute paralysis virus (IAPV), black queen cell virus (BQCV), Kashmir bee virus (KBV), acute bee paralysis virus (ABPV) and sac brood virus (SBV) in brood and adult honey bees (Apis mellifera) from colonies selected for high (HMP) and low (LMP) Varroa destructor mite population growth. Two viruses, ABPV and SBV, were never detected. For adults without mite infestation, DWV, IAPV, BQCV and KBV were detected in the HMP colony; however, only BQCV was detected in the LMP colony but at similar levels as in the HMP colony. With mite infestation, the four viruses were detected in adults of the HMP colony but all at higher amounts than in the LMP colony. For brood without mite infestation, DWV and IAPV were detected in the HMP colony, but no viruses were detected in the LMP colony. With mite infestation of brood, the four viruses were detected in the HMP colony, but only DWV and IAPV were detected and at lower amounts in the LMP colony. An epidemiological explanation for these results is that pre-experiment differences in virus presence and levels existed between the HMP and LMP colonies. It is also possible that low V. destructor population growth in the LMP colony resulted in the bees being less exposed to the mite and thus less likely to have virus infections. LMP and HMP bees may have also differed in susceptibility to virus infection.

Viral epidemiology of the adult Apis Mellifera infested by the Varroa destructor mite.

PubMed

Bernardi, Sara; Venturino, Ezio

2016-05-01

The ectoparasitic mite Varroa destructor has become one of the major worldwide threats for apiculture. Varroa destructor attacks the honey bee Apis mellifera weakening its host by sucking hemolymph. However, the damage to bee colonies is not strictly related to the parasitic action of the mite but it derives, above all, from its action as vector increasing the transmission of many viral diseases such as acute paralysis (ABPV) and deformed wing viruses (DWV), that are considered among the main causes of CCD (Colony Collapse Disorder). In this work we discuss an [Formula: see text] model that describes how the presence of the mite affects the epidemiology of these viruses on adult bees. The acronym [Formula: see text] means that the disease affects both populations. In fact it accounts for the bee and mite populations, that are each divided among the S (susceptible) and I (infected) states. We characterize the system behavior, establishing that ultimately either only healthy bees survive, or the disease becomes endemic and mites are wiped out. Another dangerous alternative is the Varroa invasion scenario with the extinction of healthy bees. The final possible configuration is the coexistence equilibrium in which honey bees share their infected hive with mites. The analysis is in line with some observed facts in natural honey bee colonies. Namely, these diseases are endemic. Further, if the mite population is present, necessarily the viral infection occurs. The findings of this study indicate that a low horizontal transmission rate of the virus among honey bees in beehives will help in protecting bee colonies from Varroa infestation and viral epidemics.

Skin mites in mice (Mus musculus): high prevalence of Myobia sp. (Acari, Arachnida) in Robertsonian mice.

PubMed

Sastre, Natalia; Calvete, Oriol; Martínez-Vargas, Jessica; Medarde, Nuria; Casellas, Joaquim; Altet, Laura; Sánchez, Armand; Francino, Olga; Ventura, Jacint

2018-07-01

Myobia sp. and Demodex sp. are two skin mites that infest mice, particularly immunodeficient or transgenic lab mice. In the present study, wild house mice from five localities from the Barcelona Roberstonian system were analysed in order to detect skin mites and compare their prevalence between standard (2n = 40) and Robertsonian mice (2n > 40). We found and identified skin mites through real-time qPCR by comparing sequences from the mitochondrial 16S rRNA and the nuclear 18S rRNA genes since no sequences are available so far using the mitochondrial gene. Fourteen positive samples were identified as Myobia musculi except for a deletion of 296 bp out to 465 bp sequenced, and one sample was identified as Demodex canis. Sampling one body site, the mite prevalence in standard and Robertsonian mice was 0 and 26%, respectively. The malfunction of the immune system elicits an overgrowth of skin mites and consequently leads to diseases such as canine demodicosis in dogs or rosacea in humans. In immunosuppressed mice, the probability of developing demodicosis is higher than in healthy mice. Since six murine toll-like receptors (TLRs) are located in four chromosomes affected by Robertsonian fusions, we cannot dismiss that differences in mite prevalence could be the consequence of the interruption of TLR function. Although ecological and/or morphological factors cannot be disregarded to explain differences in mite prevalence, the detection of translocation breakpoints in TLR genes or the analysis of TLR gene expression are needed to elucidate how Robertsonian fusions affect the immune system in mice.

A Scientific note on Varroa mites found in East Africa; Threat or Opportunity

USDA-ARS?s Scientific Manuscript database

Varroa mites have devastated Apis mellifera L. honeybee populations wherever they co-occur around the world, yet in East Africa these mites may have finally met their match. Varroa destructor Anderson and Truman (Acari:Varroidae) was found in Kenya and Tanzania for the first time in early 2009, but...

Identification of miniature inverted-repeat transposable elements (MITEs) and biogenesis of their siRNAs in the Solanaceae: New functional implications for MITEs

USDA-ARS?s Scientific Manuscript database

Small RNAs regulate the genome by guiding transcriptional and post-transcriptional silencing machinery to specific target sequences, including genes and transposable elements (TEs). Although miniature inverted-repeat transposable elements (MITEs) are closely associated with euchromatic genes, the br...

Influence of Varroa mite (Varroa destructor) infestation levels and management practices on insecticide sensitivity in the honey bee (Apis mellifera)

USDA-ARS?s Scientific Manuscript database

Because Varroa mites may cause devastating losses of honey bees through direct feeding, transmitting diseases, and increasing pathogen susceptibility, chemical and mechanical practices commonly are used to reduce mite infestation. While miticide applications are typically the most consistent and eff...

Nitric oxide fumigation for control of bulb mites on flower bulbs and tubers

USDA-ARS?s Scientific Manuscript database

Nitric oxide fumigation was studied for efficacy to control bulb mites in the genus Rhizoglyphus and effects on germination and growth of flower bulbs and tubers. Bulb mites on infested peanuts were fumigated with nitric oxide at different concentrations under ultralow oxygen conditions in 1.9L jar...

Asynchronous development of Honey Bee host and Varroa destructor (Mesostigmata: Varroidae) influences reproductive potential of mites

USDA-ARS?s Scientific Manuscript database

A high proportion of non-reproductive (NR) Varroa destructor, is commonly observed in honey bee colonies displaying the Varroa sensitive hygienic trait (VSH). These studies were conducted to determine the influence of brood removal and subsequent host re-invasion of Varroa mites on mite reproduction...

The Tropilaelaps mites threat: An examination of the injuries inflicted on Apis mellifera

USDA-ARS?s Scientific Manuscript database

Tropilaelaps spp. are the most serious parasites of Apis mellifera in Asia. However, much of their biology and ecology are largely unexplored (de Guzman et al., 2017 J. Econ. Entomol. 1-14). Like varroa mites, tropilaelaps mites puncture through the integuments of their bee hosts to feed on hemolymp...

Bee Mite ID - an online resource on identification of mites associated with bees of the World

USDA-ARS?s Scientific Manuscript database

Parasitic mites are known to be a factor in recent declines in bee pollinator populations. In particular, Varroa destructor, an introduced parasite and disease vector, has decimated colonies of the western honey bee, one of the most important agricultural pollinators in the world. Further, global tr...

Red Palm Mite Situation in the Caribbean and Florida

USDA-ARS?s Scientific Manuscript database

The red palm mite (Raoiella indica Hirst Tenuipalpidae), a pest of coconuts and ornamental palms in Asia and Africa, was reported in the Caribbean in 2004. By 2008, it had spread to at least twelve islands, two counties in Florida and to Venezuela. Red palm mite causes yellowing and leaf necrosis wi...

[ECOLOGICAL AND GEOGRAPHIC ANALYSIS OF THE SPREAD OF MITES OF THE FAMILY TROMBICULIDAE IN MONGOLIA].

PubMed

Karimova, T Yu; Kudryashova, N I; Lushchekina, A A; Neronov, V M

2016-01-01

The paper gives data on the fauna of chigger mites (Thrombiculinae), the ectoparasites of small mammals in Mongolia. The ecological and geographic analysis could reveal the major abiotic and biotic determinants of the spread of the chigger mites and make a map of their potential area.

Interactions of tropilaelaps mercedesae, honey bee viruses, and immune response in Apis mellifera

USDA-ARS?s Scientific Manuscript database

Tropilaelaps mites are the major health threat to Apis mellifera colonies in Asia because of their widespread occurrence, rapid population growth and potential ability to transfer bee viruses. Honey bee immune responses in the presence of feeding mites may occur in response to mite feeding, to the ...

The predatory mite Neoseiulus womersleyi (Acari: Phytoseiidae) follows extracts of trails left by the two-spotted spider mite Tetranychus urticae (Acari: Tetranychidae).

PubMed

Shinmen, Tsubasa; Yano, Shuichi; Osakabe, Mh

2010-10-01

As it walks, the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) spins a trail of silk threads, that is followed by the predatory mite, Neoseiulus womersleyi Schicha (Acari: Phytoseiidae). Starved adult female N. womersleyi followed T. urticae trails laid down by five T. urticae females but did not follow a trail of one T. urticae female, suggesting that the amount of spun threads and their chemical components should correlate positively with the number of T. urticae individuals. To examine whether chemical components of T. urticae trails are responsible for the predatory mite's trail following, we collected separate T. urticae threads from the exuviae and eggs, and then washed the threads with methanol to separate chemical components from physical attributes of the threads. Female N. womersleyi did not follow T. urticae trails that had been washed with methanol but contained physical residues, but they did follow the direction to which the methanol extracts of the T. urticae trails was applied. These results suggest that the predatory mite follows chemical, not physical, attributes of T. urticae trails.

Early life rhinovirus infection exacerbates house-dust-mite induced lung disease more severely in female mice.

PubMed

Phan, Jennifer A; Kicic, Anthony; Berry, Luke J; Sly, Peter D; Larcombe, Alexander N

2016-01-01

Recent studies have employed animal models to investigate links between rhinovirus infection and allergic airways disease, however, most do not involve early life infection, and none consider the effects of sex on responses. Here, we infected male and female mice with human rhinovirus 1B (or control) on day 7 of life. Mice were then subjected to 7 weeks of exposure to house-dust-mite prior to assessment of bronchoalveolar inflammation, serum antibodies, lung function, and responsiveness to methacholine. There were significant differences in responses between males and females in most outcomes. In males, chronic house-dust-mite exposure increased bronchoalveolar inflammation, house-dust-mite specific IgG1 and responsiveness of the lung parenchyma, however, there was no additional impact of rhinovirus infection. Conversely, in females, there were additive and synergistic effects of rhinovirus infection and house-dust-mite exposure on neutrophilia, airway resistance, and responsiveness of the lung parenchyma. We conclude that early life rhinovirus infection influences the development of house-dust-mite induced lung disease in female, but not male mice.

Active optical sensor assessment of spider mite damage on greenhouse beans and cotton.

PubMed

Martin, Daniel E; Latheef, Mohamed A

2018-02-01

The two-spotted spider mite, Tetranychus urticae Koch, is an important pest of cotton in mid-southern USA and causes yield reduction and deprivation in fiber fitness. Cotton and pinto beans grown in the greenhouse were infested with spider mites at the three-leaf and trifoliate stages, respectively. Spider mite damage on cotton and bean canopies expressed as normalized difference vegetation index indicative of changes in plant health was measured for 27 consecutive days. Plant health decreased incrementally for cotton until day 21 when complete destruction occurred. Thereafter, regrowth reversed decline in plant health. On spider mite treated beans, plant vigor plateaued until day 11 when plant health declined incrementally. Results indicate that pinto beans were better suited as a host plant than cotton for rearing T. urticae in the laboratory.

ST. LOUIS ENCEPHALITIS

PubMed Central

Smith, Margaret G.; Blattner, Russell J.; Heys, Florence M.

1947-01-01

Transmission of the virus of St. Louis encephalitis to normal chickens by the bite of infected mites (Dermanyssus gallinae) has been demonstrated. Both experimentally infected and naturally infected mites were shown to be capable of transferring the virus of St. Louis encephalitis to chickens by bite. Virus is present in the blood of such chickens in small amounts, so that demonstration of viremia was possible only by utilizing chorioallantoic passage in hens' eggs. However, there is sufficient virus present in the blood for uninfected chicken mites to acquire the virus by feeding on chickens in which viremia has resulted from previous bite of infected mites. Thus it has been shown that the arachnid vector Dermanyssus gallinae is capable of transmitting the virus of St. Louis encephalitis to normal chickens by bite and that such chickens can serve as a source of virus for uninfected mites. PMID:19871673

Quantitation of major allergens in dust samples from urban populations collected in different seasons in two climatic areas of the Basque region (Spain).

PubMed

Echechipía, S; Ventas, P; Audícana, M; Urrutia, I; Gastaminza, G; Polo, F; Fernández de Corres, L

1995-06-01

We present the results of allergen content evaluation in 80 dust samples from 31 homes of atopic patients from two climatic areas (humid and subhumid), collected in two seasons of the year (autumn and winter). Monoclonal antibody-based immunoassays were used to quantify Der p 1, Der f 1, Der 2, Lep d 1, and Fel d 1. The results were compared according to climate, season, and the type of sensitization (Pyroglyphidae mites, storage mites, or grass pollens). We underline the predominance of Dermatophagoides pteronyssinus (89% of samples) over D. farinae (16% of samples) in our environment. Der p 1 rates were higher in the humid area (Mann-Whitney P < 0.001), especially in the autumn (Wilcoxon P < 0.05). Lep d 1 was detected in 23% of samples and Lep d 1 levels were higher in the homes of patients sensitized to storage mites (Mann-Whitney P < 0.05), whereas this allergen was not detected in the homes of pollen-allergic patients. Fel d 1 was detected in nine of the 31 homes (16% of samples) although there was a cat in only one home.

Studies on the acaricidal mechanism of the active components from neem (Azadirachta indica) oil against Sarcoptes scabiei var. cuniculi.

PubMed

Chen, Zhen-zhen; Deng, Yun-xia; Yin, Zhong-qiong; Wei, Qin; Li, Mei; Jia, Ren-yong; Xu, Jiao; Li, Li; Song, Xu; Liang, Xiao-xia; Shu, Gang; He, Chang-liang; Gu, Xiao-bin; Lv, Cheng; Yin, Lizi

2014-08-29

Octadecanoic acid-3,4-tetrahydrofuran diester, isolated from neem (Azadirachta indica) oil, exhibited potent acaricidal activity against Sarcoptes scabiei var. cuniculi. In this paper, the acaricidal mechanism of octadecanoic acid-3,4-tetrahydrofuran diester against Sarcoptes scabiei var. cuniculi was evaluated based on pathologic histology and enzyme activities. The results showed that after compound treatment for 24h at a concentration of 20mg/mL, the lesions of mites were prominent under transmission electron microscopy. The lesions consisted of the lysis of dermis cell membranes and cell nuclear membranes, mitochondrial morphological abnormalities, the drop of spinal disorders, and mitochondrial vacuolization. The activity of superoxide dismutase (SOD), peroxidase (POD), glutathione-s-transferases (GSTs), and Ca(2+)-ATPase of mites significantly changed after treatment with octadecanoic acid-3,4-tetrahydrofuran diester compared with the control group. The activities of SOD, POD, and Ca(2+)-ATPase were significantly suppressed, whereas that of GSTs was activated. These results indicated that the mechanism of the acaricidal activity of octadecanoic acid-3,4-tetrahydrofuran diester was mainly achieved through interference with the energy metabolism of mites, thus resulting in insect death. Copyright © 2014 Elsevier B.V. All rights reserved.

Glyphosate sub-lethal toxicity to non-target organisms occurring in Jatropha curcas plantations in Brazil.

PubMed

de Saraiva, Althiéris Souza; Sarmento, Renato Almeida; Pedro-Neto, Marçal; Teodoro, Adenir Vieira; Erasmo, Eduardo Andrea Lemus; Belchior, Diana Cléssia Vieira; de Azevedo, Emiliano Brandão

2016-10-01

Weed management in physic nut plantations has generally been performed by spraying the herbicide glyphosate. However, the effects of glyphosate on non-target organisms present in the crop system are unknown. Here, we evaluated the toxicity of glyphosate (Roundup Transorb(®)) against the pest species Polyphagotarsonemus latus (Acari: Tarsonemidae) and Tetranychus bastosi (Acari: Tetranychidae) which can be exposed by drift. These mites are considered pests of the physic nut; however, they can also feed and reside on weeds associated with the crop, serving as food sources for predatory mites. When subjected to residue (by ingestion of sap of treated plants), and direct contact to glyphosate, P. latus reproduction was affected but T. bastosi was affected only by the residual effect. Although the herbicide caused a reduction in the number of eggs laid by the females of both pest mites, it is suggested that sublethal effects of glyphosate stimulates oviposition of P. latus and T. bastosi: both species displayed higher reproductive rates when exposed to 0.36 kg ha(-1) of the herbicide. We conclude that glyphosate negatively affects the arthropod herbivores studied and we discuss possible implications on their biological control in Jatropha curcas plantations.

Indoor air pollution and childhood asthma: effective environmental interventions.

PubMed Central

Etzel, R A

1995-01-01

Exposure to indoor air pollutants such as tobacco smoke and dust mites may exacerbate childhood asthma. Environmental interventions to reduce exposures to these pollutants can help prevent exacerbations of the disease. Among the most important interventions is the elimination of environmental tobacco smoke from the environments of children with asthma. However, the effectiveness of reducing asthmatic children's exposure to environmental tobacco smoke on the severity of their symptoms has not yet been systematically evaluated. Dust mite reduction is another helpful environmental intervention. This can be achieved by enclosing the child's mattresses, blankets, and pillows in zippered polyurethane-coated casings. Primary prevention of asthma is not as well understood. It is anticipated that efforts to reduce smoking during pregnancy could reduce the incidence of asthma in children. European studies have suggested that reducing exposure to food and house dust mite antigens during lactation and for the first 12 months of life diminishes the development of allergic disorders in infants with high total IgE in the cord blood and a family history of atopy. Many children with asthma and their families are not receiving adequate counseling about environmental interventions from health care providers or other sources. PMID:8549490

Field evaluation of poultry red mite (Dermanyssus gallinae) native and recombinant prototype vaccines.

PubMed

Bartley, Kathryn; Turnbull, Frank; Wright, Harry W; Huntley, John F; Palarea-Albaladejo, Javier; Nath, Mintu; Nisbet, Alasdair J

2017-09-15

Vaccination is a desirable emerging strategy to combat poultry red mite (PRM), Dermanyssus gallinae. We performed trials, in laying hens in a commercial-style cage facility, to test the vaccine efficacy of a native preparation of soluble mite extract (SME) and of a recombinant antigen cocktail vaccine containing bacterially-expressed versions of the immunogenic SME proteins Deg-SRP-1, Deg-VIT-1 and Deg-PUF-1. Hens (n=384 per group) were injected with either vaccine or adjuvant only (control group) at 12 and 17 weeks of age and then challenged with PRM 10days later. PRM counts were monitored and, at the termination of the challenge period (17 weeks post challenge), average PRM counts in cages containing birds vaccinated with SME were reduced by 78% (p<0.001), compared with those in the adjuvant-only control group. When the trial was repeated using the recombinant antigen cocktail vaccine, no statistically significant differences in mean PRM numbers were observed in cages containing vaccinated or adjuvant-only immunised birds. The roles of antigen-specific antibody levels and duration in providing vaccine-induced and exposure-related protective immunity are discussed. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Field-level sublethal effects of approved bee hive chemicals on Honey Bees (Apis mellifera L).

PubMed

Berry, Jennifer A; Hood, W Michael; Pietravalle, Stéphane; Delaplane, Keith S

2013-01-01

In a study replicated across two states and two years, we tested the sublethal effects on honey bees of the miticides Apistan (tau fluvalinate) and Check Mite+ (coumaphos) and the wood preservative copper naphthenate applied at label rates in field conditions. A continuous covariate, a colony Varroa mite index, helped us disambiguate the effects of the chemicals on bees while adjusting for a presumed benefit of controlling mites. Mite levels in colonies treated with Apistan or Check Mite+ were not different from levels in non-treated controls. Experimental chemicals significantly decreased 3-day brood survivorship and increased construction of queen supercedure cells compared to non-treated controls. Bees exposed to Check Mite+ as immatures had higher legacy mortality as adults relative to non-treated controls, whereas bees exposed to Apistan had improved legacy mortality relative to non-treated controls. Relative to non-treated controls, Check Mite+ increased adult emergence weight. Although there was a treatment effect on a test of associative learning, it was not possible to statistically separate the treatment means, but bees treated with Apistan performed comparatively well. And finally, there were no detected effects of bee hive chemical on colony bee population, amount of brood, amount of honey, foraging rate, time required for marked released bees to return to their nest, percentage of released bees that return to the nest, and colony Nosema spore loads. To our knowledge, this is the first study to examine sublethal effects of bee hive chemicals applied at label rates under field conditions while disambiguating the results from mite control benefits realized from the chemicals. Given the poor performance of the miticides at reducing mites and their inconsistent effects on the host, these results defend the use of bee health management practices that minimize use of exotic hive chemicals.

Coexistence of two different genotypes of Sarcoptes scabiei derived from companion dogs and wild raccoon dogs in Gifu, Japan: The genetic evidence for transmission between domestic and wild canids.

PubMed

Matsuyama, Ryota; Yabusaki, Toshihiro; Kuninaga, Naotoshi; Morimoto, Tomoya; Okano, Tsukasa; Suzuki, Masatsugu; Asano, Makoto

2015-09-15

Sarcoptes scabiei is the causal agent of sarcoptic mange in domestic/companion dogs (Canis lupus familiaris) and raccoon dogs (Nyctereutes procyonoides). Although there have been successful cases of experimental transmission of S. scabiei from mangy wild Canidae hosts to healthy dogs, and suspected cases of transmission between raccoon dogs and companion dogs, no clear-cut evidence has been obtained. In the present study, the genetic relationships between Sarcoptes mites from raccoon dogs and companion dogs living in the same region were elucidated.One hundred and thirty Sarcoptes mites from 22 raccoon dogs and 5 companion dogs were collected from the Gifu area in Japan. Using 9 microsatellite markers, the genotypes were compared, and the genetic structure of these mites was analyzed. In 6 pairs of companion dog- and raccoon dog-derived mites, 17 out of the 18 alleles analyzed were identical. Using a Bayesian approach, these 130 mites were separated into at least two groups, and companion dog- and raccoon dog-derived mites were segregated into both groups. In addition, comparatively large numbers of alleles at these loci were revealed by comparison with data from past studies. These results demonstrated that the host specificity at the 9 microsatellite-level could not be confirmed, strongly suggesting the transmission of Sarcoptes mites between raccoon dogs and companion dogs. This is the first report to provide a genetic evidence of Sarcoptes transmission between domestic and wild mammals in the natural environment. The possibility of a prior introduction of mites with novel genotypes (e.g., spillover of sarcoptic mange from domestic/companion dogs to raccoon dogs) could not be eliminated when considering the cause of the large number of alleles, and the coexistence of 2 mite groups in sympatric raccoon dogs and companion dogs in this local area. Copyright © 2015 Elsevier B.V. All rights reserved.

Field-Level Sublethal Effects of Approved Bee Hive Chemicals on Honey Bees (Apis mellifera L)

PubMed Central

Berry, Jennifer A.; Hood, W. Michael; Pietravalle, Stéphane; Delaplane, Keith S.

2013-01-01

In a study replicated across two states and two years, we tested the sublethal effects on honey bees of the miticides Apistan (tau fluvalinate) and Check Mite+ (coumaphos) and the wood preservative copper naphthenate applied at label rates in field conditions. A continuous covariate, a colony Varroa mite index, helped us disambiguate the effects of the chemicals on bees while adjusting for a presumed benefit of controlling mites. Mite levels in colonies treated with Apistan or Check Mite+ were not different from levels in non-treated controls. Experimental chemicals significantly decreased 3-day brood survivorship and increased construction of queen supercedure cells compared to non-treated controls. Bees exposed to Check Mite+ as immatures had higher legacy mortality as adults relative to non-treated controls, whereas bees exposed to Apistan had improved legacy mortality relative to non-treated controls. Relative to non-treated controls, Check Mite+ increased adult emergence weight. Although there was a treatment effect on a test of associative learning, it was not possible to statistically separate the treatment means, but bees treated with Apistan performed comparatively well. And finally, there were no detected effects of bee hive chemical on colony bee population, amount of brood, amount of honey, foraging rate, time required for marked released bees to return to their nest, percentage of released bees that return to the nest, and colony Nosema spore loads. To our knowledge, this is the first study to examine sublethal effects of bee hive chemicals applied at label rates under field conditions while disambiguating the results from mite control benefits realized from the chemicals. Given the poor performance of the miticides at reducing mites and their inconsistent effects on the host, these results defend the use of bee health management practices that minimize use of exotic hive chemicals. PMID:24204638

Analysis of insecticide resistance-related genes of the Carmine spider mite Tetranychus cinnabarinus based on a de novo assembled transcriptome.

PubMed

Xu, Zhifeng; Zhu, Wenyi; Liu, Yanchao; Liu, Xing; Chen, Qiushuang; Peng, Miao; Wang, Xiangzun; Shen, Guangmao; He, Lin

2014-01-01

The carmine spider mite (CSM), Tetranychus cinnabarinus, is an important pest mite in agriculture, because it can develop insecticide resistance easily. To gain valuable gene information and molecular basis for the future insecticide resistance study of CSM, the first transcriptome analysis of CSM was conducted. A total of 45,016 contigs and 25,519 unigenes were generated from the de novo transcriptome assembly, and 15,167 unigenes were annotated via BLAST querying against current databases, including nr, SwissProt, the Clusters of Orthologous Groups (COGs), Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO). Aligning the transcript to Tetranychus urticae genome, the 19255 (75.45%) of the transcripts had significant (e-value <10-5) matches to T. urticae DNA genome, 19111 sequences matched to T. urticae proteome with an average protein length coverage of 42.55%. Core Eukaryotic Genes Mapping Approach (CEGMA) analysis identified 435 core eukaryotic genes (CEGs) in the CSM dataset corresponding to 95% coverage. Ten gene categories that relate to insecticide resistance in arthropod were generated from CSM transcriptome, including 53 P450-, 22 GSTs-, 23 CarEs-, 1 AChE-, 7 GluCls-, 9 nAChRs-, 8 GABA receptor-, 1 sodium channel-, 6 ATPase- and 12 Cyt b genes. We developed significant molecular resources for T. cinnabarinus putatively involved in insecticide resistance. The transcriptome assembly analysis will significantly facilitate our study on the mechanism of adapting environmental stress (including insecticide) in CSM at the molecular level, and will be very important for developing new control strategies against this pest mite.

Laboratory evaluation of the effect of Beauveria bassiana on the predatory mite Phytoseiulus persimilis (Acari: Phytoseiidae).

PubMed

Ullah, Mohammad Shaef; Lim, Un Taek

2017-09-01

Tetranychus urticae Koch (Acari: Tetranychidae), a major pest of many agricultural crops, is mainly controlled with chemical acaricides. However, predatory mites and entomopathogens have been proposed as alternative control agents. In this study, the effect of the BotaniGard ® GHA strain of Beauveria bassiana on the survival, longevity, fecundity, and egg hatch rate of the predatory mite Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) were studied under laboratory conditions. When B. bassiana was applied directly to P. persimilis eggs at a concentration of 1×10 8 conidia/ml, corrected hatchability was less than 5%, and the corrected mortality of nymphs and adults was not significantly different from control 10days after treatment. Phytoseiulus persimilis nymphs that hatched from treated eggs showed no significant change in their development time, adult female longevity, hatch rate, survival rates over time, or offspring sex ratio. However, significant negative effects on fecundity and life table parameters (net reproductive rate, intrinsic rate of natural increase, mean generation time, finite rate of increase, and doubling time) were found when B. bassiana was applied to the adult stage. Spraying B. bassiana at 1×10 8 conidia/ml on newly emerged adults of P. persimilis caused 44% reduction in the oviposition period, 26% in adult longevity, and 63% in fecundity. Due to these negative effects, B. bassiana should be used with careful adjustment of application timing (first spray B. bassiana and then release P. persimilis) to supplement biological mite control systems using P. persimilis. Copyright © 2017 Elsevier Inc. All rights reserved.

A Field Experiment to Assess the Rate of Infestation in Honey Bee Populations of Two Metarhizium anisopliae Isolates on Varroa destructor (Acari: Mesostigmata).

PubMed

Pirali-Kheirabadi, Khodadad; Teixeira-da-Silva, Jaime A; Razzaghi-Abyaneh, Mehdi; Nazemnia, Mehdi

2013-01-01

The protective effect of two isolates of an entomopathogenic fungus, Metarhizium anisopliae (DEMI 002 and Iran 437C) on the adult stage of Varroa destructor was evaluated in comparison with fluvalinate strips in the field. A total of 12 honey bee colonies were provided from an apiculture farm. The selected hives were divided into 4 groups (3 hives per group). The first group was the control, treated with distilled water. The other two groups were exposed to different fungi (M. anisopliae isolates DEMI 002 and Iran 437C) and the last group was treated with one strip of fluvalinate per colony. The number of fallen mites was counted using sticky traps during a 6-day period, six days before and after treatments. A fungal suspension at a concentration of 5× 10(6) conidia/mL was sprayed onto the frames and the number of fallen mites was counted. Metarhizium anisopliae DEMI 002 and Iran 437C isolates were as effective (i.e., caused as much mite fall) as the fluvalinate strip in controlling bee colonies than no treatment. Both M. anisopliae isolates are promising candidates as agents in the control of Varroa mites under field conditions. Isolate DEMI 002 can be considered as a possible non-chemical biocontrol agent for controlling bee infestation with V. destructor in the field. In order to substantiate this hypothesis, tests are currently being performed using larger colonies and larger doses than tested in the present study in our beekeeping.

A Field Experiment to Assess the Rate of Infestation in Honey Bee Populations of Two Metarhizium anisopliae Isolates on Varroa destructor (Acari: Mesostigmata)

PubMed Central

Pirali-kheirabadi, Khodadad; Teixeira-da-Silva, Jaime A; Razzaghi-Abyaneh, Mehdi; Nazemnia, Mehdi

2013-01-01

Background: The protective effect of two isolates of an entomopathogenic fungus, Metarhizium anisopliae (DEMI 002 and Iran 437C) on the adult stage of Varroa destructor was evaluated in comparison with fluvalinate strips in the field. Methods: A total of 12 honey bee colonies were provided from an apiculture farm. The selected hives were divided into 4 groups (3 hives per group). The first group was the control, treated with distilled water. The other two groups were exposed to different fungi (M. anisopliae isolates DEMI 002 and Iran 437C) and the last group was treated with one strip of fluvalinate per colony. The number of fallen mites was counted using sticky traps during a 6-day period, six days before and after treatments. A fungal suspension at a concentration of 5× 106 conidia/mL was sprayed onto the frames and the number of fallen mites was counted. Results: Metarhizium anisopliae DEMI 002 and Iran 437C isolates were as effective (i.e., caused as much mite fall) as the fluvalinate strip in controlling bee colonies than no treatment. Conclusion: Both M. anisopliae isolates are promising candidates as agents in the control of Varroa mites under field conditions. Isolate DEMI 002 can be considered as a possible non-chemical biocontrol agent for controlling bee infestation with V. destructor in the field. In order to substantiate this hypothesis, tests are currently being performed using larger colonies and larger doses than tested in the present study in our beekeeping. PMID:23785691

[Skin sensitisation profiles to inhalant allergens for patients in Tétouan city (North West of Morocco)].

PubMed

Bardei, F; Bouziane, H; Kadiri, M; Rkiek, B; Tebay, A; Saoud, A

2016-08-01

The prevalence of respiratory allergies is increasing and is a serious global health problem. The objective of the study was to determine the prevalence of skin sensitization to inhalant allergens in patients consulting for respiratory allergy, to identify the main allergens involved and to evaluate the profile of skin prick-test reactivity related to sex, age and season. This retrospective study included 379 patients consulting during 2009-2012 in three private medical offices of Tetouan. Of the 379 patients, 39.6% were monosensitized and 60.4% polysensitized. The percentages of polysensitized patients were higher in patients exhibiting rhinoconjunctivitis and astma-rhinoconjunctivitis than in subjects with asthma. The prevalence of symptoms according to sex showed no significant difference (P=0.64). Regarding age, a significant difference was observed in the case of rhinoconjunctivitis (P<0.01), while asthma and asthma-rhinoconjunctivitis showed no significant difference. Sensitization to house dust mites was the most frequent followed by grasses, olives and Parietaria. The multiple correspondence analyses (ACM) showed that patients under 20-years of age with asthma and asthma-rhinoconjunctivitis profile are more associated with sensitization to mites during the spring and autumn. The 20-49-year age group was represented mainly by polysensitized patients with rhinoconjunctivitis. Sensitization to mites ranks first in Tetouan followed by the percentage of sensitized patients to grass pollen and olive. The ACM showed that the house dust mite asthma seems to affect more children and adolescents while the 20-49 year age of polysensitized group suffers significantly rhinoconjunctivitis. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Plant architecture and prey distribution influence foraging behavior of the predatory mite Phytoseiulus persimilis (Acari: Phytoseiidae).

PubMed

Gontijo, Lessando M; Nechols, James R; Margolies, David C; Cloyd, Raymond A

2012-01-01

The arrangement, number, and size of plant parts may influence predator foraging behavior, either directly, by altering the rate or pattern of predator movement, or, indirectly, by affecting the distribution and abundance of prey. We report on the effects of both plant architecture and prey distribution on foraging by the predatory mite, Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae), on cucumber (Cucumis sativus L.). Plants differed in leaf number (2- or 6-leafed), and there were associated differences in leaf size, plant height, and relative proportions of plant parts; but all had the same total surface area. The prey, the twospotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae), were distributed either on the basal leaf or on all leaves. The effect of plant architecture on predator foraging behavior varied depending on prey distribution. The dimensions of individual plant parts affected time allocated to moving and feeding, but they did not appear to influence the frequency with which predators moved among different plant parts. Overall, P. persimilis moved less, and fed upon prey longer, on 6-leafed plants with prey on all leaves than on plants representing other treatment combinations. Our findings suggest that both plant architecture and pattern of prey distribution should be considered, along with other factors such as herbivore-induced plant volatiles, in augmentative biological control programs.

Antipredator behaviours of a spider mite in response to cues of dangerous and harmless predators.

PubMed

Dias, Cleide Rosa; Bernardo, Ana Maria Guimarães; Mencalha, Jussara; Freitas, Caelum Woods Carvalho; Sarmento, Renato Almeida; Pallini, Angelo; Janssen, Arne

2016-07-01

Prey are known to invest in costly antipredator behaviour when perceiving cues of dangerous, but not of relatively harmless predators. Whereas most studies investigate one type of antipredator behaviour, we studied several types (changes in oviposition, in escape and avoidance behaviour) in the spider mite Tetranychus evansi in response to cues from two predatory mites. The predator Phytoseiulus longipes is considered a dangerous predator for T. evansi, whereas Phytoseiulus macropilis has a low predation rate on this prey, thus is a much less dangerous predator. Spider mite females oviposited less on leaf disc halves with predator cues than on clean disc halves, independent of the predator species. On entire leaf discs, they laid fewer eggs in the presence of cues of the dangerous predator than on clean discs, but not in the presence of cues of the harmless predator. Furthermore, the spider mites escaped more often from discs with cues of the dangerous predator than from discs without predator cues, but they did not escape more from discs with cues of the harmless predator. The spider mites did not avoid plants with conspecifics and predators. We conclude that the spider mites displayed several different antipredator responses to the same predator species, and that some of these antipredator responses were stronger with cues of dangerous predators than with cues of harmless predators.

Identification and gene-silencing of a putative odorant receptor transcription factor in Varroa destructor: possible role in olfaction.

PubMed

Singh, N K; Eliash, N; Stein, I; Kamer, Y; Ilia, Z; Rafaeli, A; Soroker, V

2016-04-01

The ectoparasitic mite Varroa destructor is one of the major threats to apiculture. Using a behavioural choice bioassay, we determined that phoretic mites were more successful in reaching a bee than reproductive mites, suggesting an energy trade-off between reproduction and host selection. We used both chemo-ecological and molecular strategies to identify the regulation of the olfactory machinery of Varroa and its association with reproduction. We focused on transcription regulation. Using primers designed to the conserved DNA binding region of transcription factors, we identified a gene transcript in V. destructor homologous to the pheromone receptor transcription factor (PRTF) gene of Pediculus humanus corporis. Quantitative PCR (qPCR) revealed that this PRTF-like gene transcript is expressed in the forelegs at higher levels than in the body devoid of forelegs. Subsequent comparative qPCR analysis showed that transcript expression was significantly higher in the phoretic as compared to the reproductive stage. Electrophysiological and behavioural studies revealed a reduction in the sensitivity of PRTF RNA interference-silenced mites to bee headspace, consistent with a reduction in the mites' ability to reach a host. In addition, vitellogenin expression was stimulated in PRTF-silenced mites to similar levels as found in reproductive mites. These data shed light upon the regulatory mechanism of host chemosensing in V. destructor. © 2016 The Royal Entomological Society.

Predictive 3D modelling of the interactions of pyrethroids with the voltage-gated sodium channels of ticks and mites.

PubMed

O'Reilly, Andrias O; Williamson, Martin S; González-Cabrera, Joel; Turberg, Andreas; Field, Linda M; Wallace, B A; Davies, T G Emyr

2014-03-01

The pyrethroid insecticides are a very successful group of compounds that target invertebrate voltage-gated sodium channels and are widely used in the control of insects, ticks and mites. It is well established that some pyrethroids are good insecticides whereas others are more effective as acaricides. This species specificity is advantageous for controlling particular pest(s) in the presence of another non-target invertebrate, for example controlling the Varroa mite in honeybee colonies. We applied in silico techniques to compare the voltage-gated sodium channels of insects versus ticks and mites and their interactions with a range of pyrethroids and DDT analogues. We identified a single amino acid difference within the pyrethroid binding pocket of ticks/mites that may have significant impact on the effectiveness of pyrethroids as acaricides. Other individual amino acid differences within the binding pocket in distinct tick and mite species may provide a basis for future acaricidal selectivity. Three-dimensional modelling of the pyrethroid/DDT receptor site has led to a new hypothesis to explain the preferential binding of acaricidal pyrethroids to the sodium channels of ticks/mites. This is important for understanding pyrethroid selectivity and the potential effects of mutations that can give rise to resistance to pyrethroids in commercially-important pest species. © 2013 Society of Chemical Industry.

Competitive interactions among four pest species of earth mites (Acari: Penthaleidae).

PubMed

Umina, P A; Hoffmann, A A

2005-04-01

Earth mites are major winter pests of a variety of crops and pastures in southern Australia. Competition between four earth mite species was investigated using field and shadehouse experiments. The influence of different plant hosts on the frequency and intensity of competitive interactions also were examined. This information is important, because control attempts that eradicate one species of mite could be directly followed by an increase in abundance of another earth mite species. There were strong effects of intraspecific competition on the reproductive rate of species, while interspecific interactions between Halotydeus destructor (Tucker) and Penthaleus species and between the three Penthaleus species also were detected. Competitive abilities were altered on the different plant types. On pasture, the competitive advantage swayed between Penthaleus major (Dugés), H. destructor, and Penthaleus falcatus (Qin & Halliday). Penthaleus sp. x was the strongest competitor in a mixture of wheat, Triticum aestivum (L.), and oats, Avena sativa (L.), whereas on canola, Brassica napus (L.), and bristly ox-tongue, Picris echioides (L.), P. falcatus, and H. destructor were superior competitors. These results suggest that competition is a strong force influencing the abundance of earth mites in the field and that host plant factors are important in shaping the type of interactions. This highlights the importance of identifying mite species when considering control options and suggests that effective control recommendations need to be developed for each individual species.

PCR Testing of a Ventilated Caging System to Detect Murine Fur Mites

PubMed Central

Jensen, Eric S; Allen, Kenneth P; Henderson, Kenneth S; Szabo, Aniko; Thulin, Joseph D

2013-01-01

Rodents housed in microisolation caging are commonly monitored for infectious agents by the use of soiled bedding sentinels. This strategy relies on the successful transmission of rodent pathogens from the index rodents via soiled bedding to sentinel cages and the subsequent infection or colonization of sentinel rodents. When the prevalence of a pathogen is low or the target agent is not readily transmitted by soiled bedding, alternative testing methodologies should be used. Given the continued prevalence of institutions self-reporting murine fur mites and with the advent of a new sensitive and specific PCR assay for mites, we sought to determine whether the exhaust system of an individual ventilated caging (IVC) system could be used for monitoring the rack's rodent population for mites rather than relying on the responses of sentinels. We deployed single cages of mice (Mus musculus) that were known to be infested with either Radfordia affinis or Myobia musculi on a 70-cage rack, sampled the horizontal exhaust manifolds weekly, and used the new PCR assay to test these samples for mite DNA. We detected the presence of fur mites at a 94.1% probability of detection within 4 wk of placement. Therefore, we recommend swabbing and testing the shelf exhaust manifolds of IVC racks rather than relying on soiled-bedding sentinels as an indicator of the mite status of the rodents on that rack. PMID:23562030

Whole genome amplification of Chelex-extracted DNA from a single mite: a method for studying genetics of the predatory mite Phytoseiulus persimilis.

PubMed

Konakandla, Bhanu; Park, Yoonseong; Margolies, David

2006-01-01

We developed and optimized a method using Chelex DNA extraction followed by whole genome amplification (WGA) to overcome problems conducting molecular genetic studies due to the limited amount of DNA obtainable from individual small organisms such as predatory mites. The DNA from a single mite, Phytoseiulus persimilis Athias-Henrot (Acari: Phytoseiidae), isolated in Chelex suspension was subjected to WGA. More than 1000-fold amplification of the DNA was achieved using as little as 0.03 ng genomic DNA template. The DNA obtained by the WGA was used for polymerase chain reaction followed by direct sequencing. From WGA DNA, nuclear DNA intergenic spacers ITS1 and ITS2 and a mitochondrial DNA 12S marker were tested in three different geographical populations of the predatory mite: California, the Netherlands, and Sicily. We found a total of four different alleles of the 12S in the Sicilian population, but no polymorphism was identified in the ITS marker. The combination of Chelex DNA extraction and WGA is thus shown to be a simple and robust technique for examining molecular markers for multiple loci by using individual mites. We conclude that the methods, Chelex extraction of DNA followed by WGA, provide a large quantity of DNA template that can be used for multiple PCR reactions useful for genetic studies requiring the genotypes of individual mites.

Population growth of Varroa destructor (Acari: Varroidae) in honey bee colonies is affected by the number of foragers with mites

USDA-ARS?s Scientific Manuscript database

Varroa mites are a serious pest of honey bees and the leading cause of colony losses. Varroa have relatively low reproductive rates, so populations should not increase rapidly, but often they do. Other factors might contribute to the growth of Varroa populations including mite migration into colonie...

Associations of Parameters Related to the Fall of Varroa destructor (Mesostigmata: Varroidae) in Russian and Italian Honey Bee (Hymenoptera: Apidae) Colonies

USDA-ARS?s Scientific Manuscript database

Varroa destructor (Anderson and Truman) trapped on bottom boards were assessed as indirect measurements of colony mite populations and mite fall in colonies of Russian (RHB) and Italian (I) honey bees using 29 candidate measurements. Measurements included damaged and non-damaged younger mites, damag...

Phoretic mites associated with spruce bark beetle Ips typographus L. (Curculionidae: Scolytinae) from Bulgaria

Treesearch

Danail Takov; Daniela Pilarska; John Moser

2010-01-01

A total of 818 specimens of Ips typographus L. were investigated for the presence of phoretic mites. They were collected from 4 localities in Vitosha Mountain, near Sofia. Five phoretic mites were found: Dendrolaelaps quadrisetus, Trichouropoda polytricha, Histiostoma piceae, Uroobovella ipidis and Proctolaelaps jiseri. 11.1 % from all investigated specimens of Ips...

Mite Biodiversity Under the Low Temperature Scanning Electron Microscope

USDA-ARS?s Scientific Manuscript database

To date, more than 55,000 mite species have been described and only a few of them have been studied. Some mites are adapted to live deep in soil, others in fresh or sea water, some are on plants, algae, fungi or animals, and others are able to survive in both extreme cold and hot temperatures. The...

A modular cage system design for continuous medium to large scale in vivo-rearing of predatory mites (Acari: phytoseiidae)

USDA-ARS?s Scientific Manuscript database

A new stackable modular system was developed for continuous in-vivo production of phytoseiid mites. The system consists of cage units that are filled with lima bean, Phaseolus lunatus, or red beans, P. vulgaris, leaves infested with high levels of the two-spotted spider mites, Tetranychus urticae. T...

Active optical sensor assessment of spider mite damage on greenhouse beans and cotton

USDA-ARS?s Scientific Manuscript database

The two-spotted spider mite, Tetranychus urticae Koch is an important pest of cotton in mid-southern United States and causes yield reduction, and deprivation in fiber fitness. A greenhouse colony of the spider mite was used to infest cotton and pinto beans at the three-leaf and trifoliate stages, r...

Genetic characterization of North American populations of the wheat curl mite (Aceria tosichella) and dry bulb mite (Aceria tulipae)

USDA-ARS?s Scientific Manuscript database

The wheat curl mite, Aceria tosichella Keifer, transmits at least three harmful viruses, wheat streak mosaic virus (WSMV), high plains virus (HPV), and Triticum mosaic virus (TriMV) to wheat (Triticum aestivum L.) throughout the Great Plains. This virus complex is considered to be the most serious d...

Observations on the mite Schizosthetus lyriformis (Acari: Parasitidae) preying on bark beetle eggs and larve

Treesearch

Richard W. Hofstetter; J. C. Moser; R. McGuire

2009-01-01

Many species of mite that live exclusively in decaying wood and subcortical environments have intricate relationships with bark beetles (Coleoptera: Curculionidae, Scolytinae) (e.g., in the genus Dendroctonus, Ips, Scolytus) (Lindquist, 1969; Moser, 1975; Hirschmann and Wisniewski, 1983; Karg, 1993). These mites depend on bark beetles or other subcorticolous insects...

New Collection Records and Host Range of the Cottonwood Leafcurl Mite, Tetra Loblulifera (Keifer) (Acari: Eriophyidae), in the USA

Treesearch

David R. Coyle; James Q. Amrine

2004-01-01

The cottonwood leafcurl mite, Aculops lobuliferus Keifer, 1961, is renamed as Tetra lobulifera (Keifer). This eriophyid mite is capable of inflicting substantial damage on plantation- and native-grown cottonwoods (Populus spp.). We report new State and County collection records from the eastern and northwestern U...

Tarsonemid mite associates of Dendroctonus frontalis (Coleoptera: Scolytidae): implications for the historical biogeography of D. frontalis

Treesearch

John C. Moser; Jorge E. Macías-Sámano

2000-01-01

Seven species of mites (Acari: Tarsenomidae) were associated with two local outbreaks of the southern pine beetle, Dendroctonus frontalis Zimmerman, in Chiapas, Mexico; three of these species were new records for Mexico and Central America. The morphology and phoretic behavior of these mites differed little between the western and southern...

New approach for the study of mite reproduction: the first transcriptome analysis of a mite, Phytoseiulus persimilis (Acari: Phytoseiidae)

USDA-ARS?s Scientific Manuscript database

Many species of mites and ticks are of agricultural and medical importance. Much can be learned from the study of transcriptomes of acarines which can generate DNA-sequence information of potential target genes for the control of acarine pests. High throughput transcriptome sequencing can also yie...

Confirmation of Neozygites floridana azygospore formation in two-spotted spider mite (Tetranychus urticae) in strains from tropical and temperature regions

USDA-ARS?s Scientific Manuscript database

Neozygites floridana is an obligate fungal pathogen of mites in the family Tetranychidae and is an important natural enemy of the two-spotted spider mite (Tetranychus urticae). Until now, information about the formation of azygospores remained to be fully confirmed. In this study, we document the fo...

Carpoglyphus lactis (Acari: Astigmata) from various dried fruits differed in associated micro-organisms.

PubMed

Hubert, J; Nesvorná, M; Kopecký, J; Ságová-Marečková, M; Poltronieri, P

2015-02-01

Carpoglyphus lactis is a stored product mite infesting saccharide-rich stored commodities including dried fruits, wine, beer, milk products, jams and honey. The association with micro-organisms can improve the survival of mites on dried fruits. The microbial communities associated with C. lactis were studied in specimens originating from the packages of dried apricot, plums and figs and compared to the laboratory strain reared on house dust mite diet (HDMd). Clone libraries of bacterial 16S rRNA gene and fungal internal transcribed spacer (ITS) region were constructed and analysed by operational taxonomic unit (OTU) approach. The 16S rRNA gene libraries differed among the compared diets. The sequences classified to the genera Leuconostoc, Elizabethkingia, Ewingella, Erwinia, Bacillus and Serratia were prevailing in mites sampled from the dried fruits. The ITS library showed smaller differences between the laboratory strain on HDMd and the isolates from dried fruits packages, with the exception of the mite strain from dried plums. The population growth was used as an indirect indicator of fitness and decreased in the order from yeast diet to HDMd and dried fruits. The treatment and pretreatment of mites by antibiotics did not reveal the presence of antagonistic bacteria which might slow down the C. lactis population growth. The shifts of the microbial community in the gut of C. lactis were induced by the diet changes. The identified yeasts and bacteria are suggested as the main food source of stored product mites on dried fruits. The study describes the adaptation of C. lactis to feeding on dried fruits including the interaction with micro-organisms. We also identified potentially pathogenic bacteria carried by the mites to dried fruits for human consumption. © 2014 The Society for Applied Microbiology.

Detection of Dermatophagoides farinae in the dust of air conditioning filters.

PubMed

Liu, Zhigang; Bai, Yu; Ji, Kunmei; Liu, Xiaoyu; Cai, Chengyu; Yu, Haiqiong; Li, Meng; Bao, Ying; Lian, Yuyin; Gao, Bo

2007-01-01

The allergenic dust mite species Dermatophagoides pteronyssinus and Dermatophagoides farinae generally inhabit warm moist environments. This study tested the hypothesis that these allergenic species may thrive in air conditioner filters. A year-long investigation of the dust mite population densities and species identities living in air conditioner filters in Shenzhen City in Southern China was performed. Additional data describing the levels of major dust mite allergen proteins from samples collected in July and August 2004 were analyzed. Genetic polymorphism analysis of Der f 1 and Der f 2 genes in the collected animals was also conducted. Our investigation revealed that larval dust mites started to grow in March, from which time their populations proceeded to steadily increase until reaching their population zenith in July and August. The dust mite populations decreased sharply in October and live dust mites were no longer observed in the winter. Among the mites collected in July and August, 30.1 and 25.8% were of the species D. farinae. The concentration of Der f 1 was 3.04 +/- 1.75 and 3.21 +/- 1.84 microg/g dust in July and August, respectively, and that of Der f 2 was 2.15 +/- 0.82 and 2.04 +/- 1.15 microg/g dust. Four types of Der f 1 and 5 types of Der f 2 cDNA sequences were cloned from collected Der f mites. Their sequences were highly homologous with those previously published in GenBank (No. AB034946.1 and No. AB195580.1). This research demonstrated that Der f allergens exist in the dust of air conditioner filters in this area.

Air-conditioner filters enriching dust mites allergen.

PubMed

Zhan, Xiaodong; Li, Chaopin; Xu, Haifeng; Xu, Pengfei; Zhu, Haibin; Diao, Jidong; Li, Na; Zhao, Beibei

2015-01-01

We detected the concentration of dust mites allergen (Der f1 & Der p1) in the air of different places before and after the starting of air-conditioners in Wuhu City, Anhui, China, and to discuss the relation between the dust mites allergen in air-conditioner filters and the asthma attack. The dust samples were collected from the air-conditioner filters in dining rooms, shopping malls, hotels and households respectively. Concentrations of dust mites major group allergen 1 (Der f 1, Der p1) were detected with enzyme linked immunosorbent assay (ELISA), and the dust mite immune activities were determined by dot-ELISA. The concentration of Der f1 in dining rooms, shopping malls, hotels and households was 1.52 μg/g, 1.24 μg/g, 1.31 μg/g and 1.46 μg/g respectively, and the concentration of Der p1 in above-mentioned places was 1.23 μg/g, 1.12 μg/g, 1.16 μg/g and 1.18 μg/g respectively. The concentration of Der f1 & Der p1 in air was higher after the air-conditioners starting one hours later, and the difference was significant (P<0.05, respectively). Additionally, dot-ELISA findings revealed that the allergen extracted from the dust was capable of reacting with IgE from the sera of asthma mice allergic to dust mites. The study concludes that air-conditioner filters can enrich dust mites major group allergen, and the allergens can induce asthma. The air-conditioner filters shall be cleaned or replaced regularly to prevent or reduce accumulation of the dust mites and its allergens.

Air-conditioner filters enriching dust mites allergen

PubMed Central

Zhan, Xiaodong; Li, Chaopin; Xu, Haifeng; Xu, Pengfei; Zhu, Haibin; Diao, Jidong; Li, Na; Zhao, Beibei

2015-01-01

We detected the concentration of dust mites allergen (Der f1 & Der p1) in the air of different places before and after the starting of air-conditioners in Wuhu City, Anhui, China, and to discuss the relation between the dust mites allergen in air-conditioner filters and the asthma attack. The dust samples were collected from the air-conditioner filters in dining rooms, shopping malls, hotels and households respectively. Concentrations of dust mites major group allergen 1 (Der f 1, Der p1) were detected with enzyme linked immunosorbent assay (ELISA), and the dust mite immune activities were determined by dot-ELISA. The concentration of Der f1 in dining rooms, shopping malls, hotels and households was 1.52 μg/g, 1.24 μg/g, 1.31 μg/g and 1.46 μg/g respectively, and the concentration of Der p1 in above-mentioned places was 1.23 μg/g, 1.12 μg/g, 1.16 μg/g and 1.18 μg/g respectively. The concentration of Der f1 & Der p1 in air was higher after the air-conditioners starting one hours later, and the difference was significant (P<0.05, respectively). Additionally, dot-ELISA findings revealed that the allergen extracted from the dust was capable of reacting with IgE from the sera of asthma mice allergic to dust mites. The study concludes that air-conditioner filters can enrich dust mites major group allergen, and the allergens can induce asthma. The air-conditioner filters shall be cleaned or replaced regularly to prevent or reduce accumulation of the dust mites and its allergens. PMID:26064381

Lower Virus Infections in Varroa destructor-Infested and Uninfested Brood and Adult Honey Bees (Apis mellifera) of a Low Mite Population Growth Colony Compared to a High Mite Population Growth Colony

PubMed Central

Emsen, Berna; Hamiduzzaman, Mollah Md.; Goodwin, Paul H.; Guzman-Novoa, Ernesto

2015-01-01

A comparison was made of the prevalence and relative quantification of deformed wing virus (DWV), Israeli acute paralysis virus (IAPV), black queen cell virus (BQCV), Kashmir bee virus (KBV), acute bee paralysis virus (ABPV) and sac brood virus (SBV) in brood and adult honey bees (Apis mellifera) from colonies selected for high (HMP) and low (LMP) Varroa destructor mite population growth. Two viruses, ABPV and SBV, were never detected. For adults without mite infestation, DWV, IAPV, BQCV and KBV were detected in the HMP colony; however, only BQCV was detected in the LMP colony but at similar levels as in the HMP colony. With mite infestation, the four viruses were detected in adults of the HMP colony but all at higher amounts than in the LMP colony. For brood without mite infestation, DWV and IAPV were detected in the HMP colony, but no viruses were detected in the LMP colony. With mite infestation of brood, the four viruses were detected in the HMP colony, but only DWV and IAPV were detected and at lower amounts in the LMP colony. An epidemiological explanation for these results is that pre-experiment differences in virus presence and levels existed between the HMP and LMP colonies. It is also possible that low V. destructor population growth in the LMP colony resulted in the bees being less exposed to the mite and thus less likely to have virus infections. LMP and HMP bees may have also differed in susceptibility to virus infection. PMID:25723540

Mitochondrial Genome Sequence of the Scabies Mite Provides Insight into the Genetic Diversity of Individual Scabies Infections

PubMed Central

Mofiz, Ehtesham; Seemann, Torsten; Bahlo, Melanie; Holt, Deborah; Currie, Bart J.

2016-01-01

The scabies mite, Sarcoptes scabiei, is an obligate parasite of the skin that infects humans and other animal species, causing scabies, a contagious disease characterized by extreme itching. Scabies infections are a major health problem, particularly in remote Indigenous communities in Australia, where co-infection of epidermal scabies lesions by Group A Streptococci or Staphylococcus aureus is thought to be responsible for the high rate of rheumatic heart disease and chronic kidney disease. We collected and separately sequenced mite DNA from several pools of thousands of whole mites from a porcine model of scabies (S. scabiei var. suis) and two human patients (S. scabiei var. hominis) living in different regions of northern Australia. Our sequencing samples the mite and its metagenome, including the mite gut flora and the wound micro-environment. Here, we describe the mitochondrial genome of the scabies mite. We developed a new de novo assembly pipeline based on a bait-and-reassemble strategy, which produced a 14 kilobase mitochondrial genome sequence assembly. We also annotated 35 genes and have compared these to other Acari mites. We identified single nucleotide polymorphisms (SNPs) and used these to infer the presence of six haplogroups in our samples, Remarkably, these fall into two closely-related clades with one clade including both human and pig varieties. This supports earlier findings that only limited genetic differences may separate some human and animal varieties, and raises the possibility of cross-host infections. Finally, we used these mitochondrial haplotypes to show that the genetic diversity of individual infections is typically small with 1–3 distinct haplotypes per infestation. PMID:26872064

Reflectance confocal microscopy vs. standardized skin surface biopsy for measuring the density of Demodex mites.

PubMed

Turgut Erdemir, A; Gurel, M S; Koku Aksu, A E; Bilgin Karahalli, F; Incel, P; Kutlu Haytoğlu, N S; Falay, T

2014-11-01

Reflectance confocal microscopy (RCM) has been recently shown to be effective for measuring the Demodex mite density. To compare and demonstrate the advantages and disadvantages of standardized skin surface biopsy (SSSB) and RCM for measuring the density of Demodex mites. Forty-eight patients (30 female, 18 male) and 47 healthy controls (30 female, 17 male) were enrolled in the study. The patients diagnoses were pityriasis folliculorum (n = 40), papulopustulary rosecea (n = 7) and erythema-telengiectatic rosacea (n = 1). The area with the most intense erythema on the right cheek was selected for imaging with RCM (VivaScope 3000) and SSSB. Forty-two patients demonstrated high Demodex density [(Dd) > 5 mites/cm(2) ] with SSSB (85.7%). RCM identified demodicosis in 48 patients (100%). The mean Dd measured with RCM (409.8 ± 209.2) was significantly higher than SSSB (15.33 ± 18.1) (P < 0.001). In the patients, RCM demonstrated the mean number of mites 40.90 ± 20.9 and 4.11 ± 6.4 in the controls per 10 mm(2) area. The corresponding mean number of 2.63 ± 0.77 mites was detected in the infested follicles per area of view compared to a mean of 0.77 ± 0.98 mites in the infested follicles in the controls (P < 0.001). Reflectance confocal microscopy is a fast, direct and noninvasive method for Demodex-associated diseases and it is superior to SSSB for Demodex mite detection. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Mitochondrial Genome Sequence of the Scabies Mite Provides Insight into the Genetic Diversity of Individual Scabies Infections.

PubMed

Mofiz, Ehtesham; Seemann, Torsten; Bahlo, Melanie; Holt, Deborah; Currie, Bart J; Fischer, Katja; Papenfuss, Anthony T

2016-02-01

The scabies mite, Sarcoptes scabiei, is an obligate parasite of the skin that infects humans and other animal species, causing scabies, a contagious disease characterized by extreme itching. Scabies infections are a major health problem, particularly in remote Indigenous communities in Australia, where co-infection of epidermal scabies lesions by Group A Streptococci or Staphylococcus aureus is thought to be responsible for the high rate of rheumatic heart disease and chronic kidney disease. We collected and separately sequenced mite DNA from several pools of thousands of whole mites from a porcine model of scabies (S. scabiei var. suis) and two human patients (S. scabiei var. hominis) living in different regions of northern Australia. Our sequencing samples the mite and its metagenome, including the mite gut flora and the wound micro-environment. Here, we describe the mitochondrial genome of the scabies mite. We developed a new de novo assembly pipeline based on a bait-and-reassemble strategy, which produced a 14 kilobase mitochondrial genome sequence assembly. We also annotated 35 genes and have compared these to other Acari mites. We identified single nucleotide polymorphisms (SNPs) and used these to infer the presence of six haplogroups in our samples, Remarkably, these fall into two closely-related clades with one clade including both human and pig varieties. This supports earlier findings that only limited genetic differences may separate some human and animal varieties, and raises the possibility of cross-host infections. Finally, we used these mitochondrial haplotypes to show that the genetic diversity of individual infections is typically small with 1-3 distinct haplotypes per infestation.

Jasmonic Acid Is a Key Regulator of Spider Mite-Induced Volatile Terpenoid and Methyl Salicylate Emission in Tomato1[w

PubMed Central

Ament, Kai; Kant, Merijn R.; Sabelis, Maurice W.; Haring, Michel A.; Schuurink, Robert C.

2004-01-01

The tomato (Lycopersicon esculentum) mutant def-1, which is deficient in induced jasmonic acid (JA) accumulation upon wounding or herbivory, was used to study the role of JA in the direct and indirect defense responses to phytophagous mites (Tetranychus urticae). In contrast to earlier reports, spider mites laid as many eggs and caused as much damage on def-1 as on wild-type plants, even though def-1 lacked induction of proteinase inhibitor activity. However, the hatching-rate of eggs on def-1 was significantly higher, suggesting that JA-dependent direct defenses enhanced egg mortality or increased the time needed for embryonic development. As to gene expression, def-1 had lower levels of JA-related transcripts but higher levels of salicylic acid (SA) related transcripts after 1 d of spider mite infestation. Furthermore, the indirect defense response was absent in def-1, since the five typical spider mite-induced tomato-volatiles (methyl salicylate [MeSA], 4,8,12-trimethyltrideca-1,3,7,11-tetraene [TMTT], linalool, trans-nerolidol, and trans-β-ocimene) were not induced and the predatory mite Phytoseiulus persimilis did not discriminate between infested and uninfested def-1 tomatoes as it did with wild-type tomatoes. Similarly, the expression of the MeSA biosynthetic gene salicylic acid methyltransferase (SAMT) was induced by spider mites in wild type but not in def-1. Exogenous application of JA to def-1 induced the accumulation of SAMT and putative geranylgeranyl diphosphate synthase transcripts and restored MeSA- and TMTT-emission upon herbivory. JA is therefore necessary to induce the enzymatic conversion of SA into MeSA. We conclude that JA is essential for establishing the spider mite-induced indirect defense response in tomato. PMID:15310835

Rhinovirus exacerbates house-dust-mite induced lung disease in adult mice.

PubMed

Phan, Jennifer A; Kicic, Anthony; Berry, Luke J; Fernandes, Lynette B; Zosky, Graeme R; Sly, Peter D; Larcombe, Alexander N

2014-01-01

Human rhinovirus is a key viral trigger for asthma exacerbations. To date, murine studies investigating rhinovirus-induced exacerbation of allergic airways disease have employed systemic sensitisation/intranasal challenge with ovalbumin. In this study, we combined human-rhinovirus infection with a clinically relevant mouse model of aero-allergen exposure using house-dust-mite in an attempt to more accurately understand the links between human-rhinovirus infection and exacerbations of asthma. Adult BALB/c mice were intranasally exposed to low-dose house-dust-mite (or vehicle) daily for 10 days. On day 9, mice were inoculated with human-rhinovirus-1B (or UV-inactivated human-rhinovirus-1B). Forty-eight hours after inoculation, we assessed bronchoalveolar cellular inflammation, levels of relevant cytokines/serum antibodies, lung function and responsiveness/sensitivity to methacholine. House-dust-mite exposure did not result in a classical TH2-driven response, but was more representative of noneosinophilic asthma. However, there were significant effects of house-dust-mite exposure on most of the parameters measured including increased cellular inflammation (primarily macrophages and neutrophils), increased total IgE and house-dust-mite-specific IgG1 and increased responsiveness/sensitivity to methacholine. There were limited effects of human-rhinovirus-1B infection alone, and the combination of the two insults resulted in additive increases in neutrophil levels and lung parenchymal responses to methacholine (tissue elastance). We conclude that acute rhinovirus infection exacerbates house-dust-mite-induced lung disease in adult mice. The similarity of our results using the naturally occurring allergen house-dust-mite, to previous studies using ovalbumin, suggests that the exacerbation of allergic airways disease by rhinovirus infection could act via multiple or conserved mechanisms.