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1.
PLoS One ; 17(6): e0270009, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35709209

RESUMO

Nasopulmonary mites (NPMs) of the family Halarachnidae are obligate endoparasites that colonize the respiratory tracts of mammals. NPMs damage surface epithelium resulting in mucosal irritation, respiratory illness, and secondary infection, yet the role of NPMs in facilitating pathogen invasion or dissemination between hosts remains unclear. Using 16S rRNA massively parallel amplicon sequencing of six hypervariable regions (or "16S profiling"), we characterized the bacterial community of NPMs from 4 southern sea otters (Enhydra lutris nereis). This data was paired with detection of a priority pathogen, Streptococcus phocae, from NPMs infesting 16 southern sea otters and 9 California sea lions (Zalophus californianus) using nested conventional polymerase chain reaction (nPCR). The bacteriome of assessed NPMs was dominated by Mycoplasmataceae and Vibrionaceae, but at least 16 organisms with pathogenic potential were detected as well. Importantly, S. phocae was detected in 37% of NPM by nPCR and was also detected by 16S profiling. Detection of multiple organisms with pathogenic potential in or on NPMs suggests they may act as mechanical vectors of bacterial infection for marine mammals.


Assuntos
Caniformia , Ácaros , Lontras , Leões-Marinhos , Animais , Caniformia/genética , Cetáceos/genética , Ácaros/genética , Lontras/genética , RNA Ribossômico 16S/genética , Leões-Marinhos/genética , Streptococcus/genética
2.
Braz J Biol ; 84: e261262, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35703629

RESUMO

Promising bioactivities of silver nanoparticles SNP urged researchers of different specialties to evaluate their field-respective activities. Bioactivity towards agricultural pests were the subject of limited publications. In the current study, SNP were synthesized and miticidal activity was evaluated towards old world date mite Oligonychus afrasiaticus (McGregor) (Acari: Tetranychidae) and an associated predatory mite Neoseiulus barkeri Hughes (Phytoseiidae). Under laboratory conditions, SNP displayed significantly higher activity towards O. afrasiaticus (LC50 was 39.7 µg/mL) than N. barkeri (LC50 was 1587.9 µg/mL) which accounts for about 40 folds of selectivity against the pest. SNP exhibited ovicidal activity against laid eggs of O. afrasiaticus (LC50 was 67.8 µg/mL). In field, SNP (at 216 µg/mL) achieved slightly higher efficiency than in laboratory study, 86.5% of population reduction of O. afrasiaticus was achieved and only 18.5% of N. barkeri population was affected. SNP suppressed hatching of 57.1% of laid eggs of O. afrasiaticus. Residues of silver were determined using ICP-OES spectrometry. Initial residues reached 1.83 µg/mL after application then declined with time passing. Estimated daily intake (EDI) reached 1.28 µg/kg/day, calculated for the highest residues obtained and the highest consumption rate of date in the world. Hazard index (Hi) was 0.17 in average. The obtained level of residues appeared to be safe in terms of acute and chronic toxicity references.


Assuntos
Nanopartículas Metálicas , Ácaros , Phoeniceae , Tetranychidae , Animais , Nanopartículas Metálicas/toxicidade , Controle Biológico de Vetores , Comportamento Predatório , Medição de Risco , Prata/farmacologia
3.
PLoS One ; 17(6): e0268964, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35704591

RESUMO

A molecular genetic and morphometric investigation revealed the supposedly widespread Caribbean and Western Atlantic intertidal oribatid mite species Fortuynia atlantica to comprise at least two different species. Although there are no distinct morphological differences separating these taxa, COI and 18S sequence divergence data, as well as different species delimitation analyses, clearly identify the two species. Fortuynia atlantica is distributed in the northern Caribbean and the Western Atlantic and the new Fortuynia antillea sp. nov. is presently endemic to Barbados. Vicariance is supposed to be responsible for their genetic diversification and stabilizing selection caused by the extreme intertidal environment is suggested to be the reason for the found morphological stasis. The genetic structure of Fortuynia atlantica indicates that Bermudian populations are derived from the northern Caribbean and thus support the theory of dispersal by drifting on the Gulf Stream. Haplotype network data suggest that Bermudian and Bahamian populations were largely shaped by colonization, expansion and extinction events caused by dramatic sea level changes during the Pleistocene. A preliminary phylogenetic analysis based on 18S gene sequences indicates that the globally distributed genus Fortuynia may be a monophyletic group, whereas Caribbean and Western Atlantic members are distinctly separated from the Indo-Pacific and Western Pacific species.


Assuntos
Ácaros , Animais , Barbados , Região do Caribe , Haplótipos , Ácaros/anatomia & histologia , Ácaros/genética , Filogenia
4.
BMC Ecol Evol ; 22(1): 80, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35729504

RESUMO

BACKGROUND: The ecology and evolution of phoretic mites and termites have not been well studied. In particular, it is unknown whether the specific relationship between mites and termites is commensal or parasitic. High phoretic mite densities have often been found to occur in weak termite colonies, suggesting that the relationship is closer to that of parasitism than commensalism. RESULTS: To examine this, Coptotermes formosanus was used as a carrier, and Acarus farris as the phoretic mite. We used video recordings to observe termite social immunity behaviors and bioassay to examine termite fitness. Our results showed that the attachment of the mite on the termite can enhance termite social immunity behaviors like alarm vibration and grooming frequency while decreasing the duration of individual grooming episodes in phoretic mites. Further, A. farris phoresy led to a 22.91% reduction in termite abdomen volume and a 3.31-fold increase in termite mortality. CONCLUSIONS: When termites groom more frequently, the consequence is short duration of grooming bouts. This may be indicative of a trade-off which provides suggestive evidence that frequent social behaviors may cost termites energy. And this caused phoretic behavior hastened termites' death, and helped propagate the population of mites feeding on dead termites. So, it provides a case for phoresy being a precursor to parasitism, and the specific relationship between A. farris and C. formosanus is closer to parasitism than to commensalism.


Assuntos
Isópteros , Ácaros , Animais , Asseio Animal , Comportamento Social , Simbiose
5.
Rev Bras Parasitol Vet ; 31(2): e003122, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35674533

RESUMO

Parasitic otitis in cattle, caused by mites, has been reported from several continents. The present study aimed to determine the distribution, prevalence, intensity, mean intensity, and range of the agent in cattle in the state of Mato Grosso do Sul, Brazil. The samples were designed at random, with an acceptable margin of error of 3% and a confidence interval of 99%. A total of 449 animals were sampled immediately after slaughter from 34 different municipalities in the state using the technique of flushing both ear canals. Only Raillietia auris (Leidy, 1872) were found, with a prevalence of 98.6%, mean intensity of 53.78 mites/animal, and a range of 1-323. Impressively, the prevalence found was identical to another survey carried out 39 years ago in the same region. Details about the parasite intensity in different age categories of the animals are presented. The study demonstrates that the prevalence and intensity of infestation by Raillietia auris are high, and in older cattle are higher than young ones.


Assuntos
Doenças dos Bovinos , Infestações por Ácaros , Ácaros , Animais , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Infestações por Ácaros/epidemiologia , Infestações por Ácaros/parasitologia , Infestações por Ácaros/veterinária
6.
Pak J Biol Sci ; 25(5): 406-414, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35638511

RESUMO

<b>Background and Objective:</b> <i>Demodex</i> mites are considered to play a pathogenic role in facial dermatoses as <i>Acne vulgaris</i>. In this study the association between <i>Acne vulgaris</i> and <i>Demodex</i> spp. intensity, kind and activity were investigated. <b>Materials and Methods:</b> Two degrees of acne was included, mild acne (30 cases) and moderate to severe acne (30 cases), besides 30 healthy subjects as a control. Deep skin scraping followed by direct microscopic detection was applied to diagnose demodicosis. <b>Results:</b> All the detected mites in moderate to severe acne were <i>D. folliculorum</i> which was observed in a highly dynamic status with their entire life cycle stages with intensity >5 mites per cm<sup><a href="2246157_ja">2</a></sup>. While very few inactive <i>D. brevis</i> mites were detected in the 2 subjects related to the control group<i>. </i>Despite that females comprised the majority of acne cases, males encompassed a statistically higher number than females among positive demodicosis cases. Itching and hair loss were the significant clinical signs within positive cases. Regarding risk factors, oily skins, repeated exposure to the sun, stressful lifestyle plus defective use of facial cleansers were found to be statistically significant. <b>Conclusion:</b> These results attained an association between moderate to severe acne and energetic <i>D. folliculorum</i> entire population. Thus, this study recommended lifestyle's modification for those cases suffering from <i>Acne vulgaris</i> with deep facial cleaning to avoid such infestation that worsens acne condition. Accordingly, once acne treatments are ineffective, consideration of <i>Demodex</i> mites with the needed acaricidal therapy is necessary.


Assuntos
Acne Vulgar , Infestações por Ácaros , Ácaros , Acne Vulgar/diagnóstico , Acne Vulgar/epidemiologia , Animais , Egito/epidemiologia , Feminino , Humanos , Masculino , Infestações por Ácaros/diagnóstico , Infestações por Ácaros/epidemiologia , Fatores de Risco
7.
Acta Trop ; 232: 106509, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35569525

RESUMO

More than ever, there is a need to understand how pathogens, vectors and hosts occur temporally and spatially to predict the occurrence of zoonotic outbreaks. Related to this, mites of the Mesostigmata and Trombidiformes orders have the potential to transmit several diseases, yet their information of occurrence, distribution and zoonotic accompanying agents have not been systematically organized. We conducted a systematic review using a combination of words through the Sysrev platform, as well as literature searches in specialised databases to identify global patterns of infections, trends in mite-rodent-pathogen research and existing knowledge gaps. The inclusion criterion was the detection of pathogens in mites, either by molecular or serological techniques or by direct observation under the microscope, which rendered 125 papers. Most works have been carried out in Asia, mainly around the transmission of Orientia tsutsugamushi. Interestingly, co-infections, i.e., the presence of more than one pathogen in an individual, are common in other Acari groups such as ticks. Moreover, this is not the case for Trombidiformes and Mesostigmata as only 4.7 percent of the articles reviewed detected more than one pathogen in these mites. It is important to include a multi-host, multi-vector and multi-pathogen approaches to understand complex systems in disease ecology. A synergy between mite taxonomists, physicians and veterinarians, decision-makers, governmental organisations, and society is needed to address the emergence of mite-borne new or neglected diseases.


Assuntos
Ácaros , Orientia tsutsugamushi , Animais , Ásia , Vetores de Doenças , Roedores
8.
Braz J Biol ; 84: e257975, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35588516

RESUMO

Galling insects are abundant in nature, found in many ecosystems globally, with species attacking plants of economic importance. We studied the effects of free-feeding organisms on the abundance of galling insects on Caryocar brasiliense (Caryocaraceae) trees in the Brazilian Cerrado (Savanna). Percentage of defoliation and the number of phytophagous mites or number of phytophagous Hemiptera correlated negatively with percentage of galled leaves and the parasitoid Eurytoma sp. (Hymenoptera: Eurytomidae) adults, respectively. Percentage of galled leaves and the numbers of Eurytoma sp. adults and phytophagous mites correlated positively with spiders. Numbers of mites and Hemiptera phytophagous correlated positively with those of lady beetles and Sycophila sp. (Hymenoptera: Eurytomidae), respectively. The number of Ablerus magistretti Blanchard (Hymenoptera: Aphelinidae) adults correlated negatively with Sycophila sp. The number of Agistemus sp. (Acari: Stigmaeidae) correlated, negatively and positively, with those of lady beetles and phytophagous mites, respectively. Free-feeding herbivores affected the presence of galling insects (Hymenoptera) on C. brasiliense trees, competing for food and space. The same was observed between two parasitoids of Eurytoma sp. galling insect, which can reduce the natural biological control of this pest.


Assuntos
Besouros , Hemípteros , Himenópteros , Malpighiales , Ácaros , Animais , Brasil , Ecossistema , Pradaria , Humanos , Insetos , Plantas , Árvores
9.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 34(2): 179-182, 2022 Feb 23.
Artigo em Chinês | MEDLINE | ID: mdl-35537840

RESUMO

OBJECTIVE: To investigate the morphological characteristics of Dermatophagoides farinae at different developmental stages. METHODS: The cultured D. farinae was isolated, and the external morphological features of mites at various developmental stages were observed using scanning electron microscopy (SEM), including egg, larva, nymph and adult stages. RESULTS: The D. farinae egg appeared a long oval shape, and the larval mites had three pairs of legs. The nymph had four pairs of legs and underdeveloped genital pores containing genital setae and anal setae, and adult mites appeared long and oval in shape, with decorative patterns on epidermis, and had four pairs of legs. In male adult mites, remarkable thickening of the leg I and thicker and longer leg III than the leg IV were seen, and ventral genital regions were found between the basal segments of legs III and IV; the anus was surrounded by a circular peri-anal ring, with a pair of anal suckers and anal setae within the ring. In the female adult mites, slender legs III and IV with an equal length were seen, and a "λ-shape" genital hole was observed on the ventral surface, with a crescent-like genital plate in the anterior part, and the anus appeared a longitudinal slit. CONCLUSIONS: An SEM observation of the external morphology of D. farinae provides understandings of the morphological characteristics of D. farinae, which is of great significance for the classification and identification.


Assuntos
Dermatophagoides farinae , Ácaros , Animais , Elétrons , Feminino , Larva/anatomia & histologia , Masculino , Microscopia Eletrônica de Varredura , Ninfa/ultraestrutura
10.
Bull Entomol Res ; 112(3): 389-398, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35543299

RESUMO

Non-crop plant diversity plays a fundamental role in the conservation of predatory mite (PM) and can be proposed as a banker plant system (BPS). BPSs provide plants that host natural enemies in greenhouses or field crops and may improve the efficiency of biological control. The aim of this study was to investigate if a diverse plant composition could be a suitable BPS for PMs in strawberry crops. A plant inventory characterized 22 species of non-crop plants harboring PMs. The most abundant PMs, in decreasing order, were Neoseiulus californicus, Neoseiulus anonymus, Euseius citrifolius, and Euseius concordis. PMs were randomly distributed among plants. We also found specific associations of Phytoseiidae species and phytophagous or generalist mites on plants. Due to this, four species were deemed suitable as banker plants: Capsicum sp., Leonurus sibiricus, Solanum americanum, and Urochloa mutica. Moreover, these plants combined a high PMs density and a low occurrence or absence of pest-mites. This study suggests shifting the traditional view that BPSs are composed of a limited number of species to use plant assemblages. This contributes to both conservation and augmentative biological control.


Assuntos
Fragaria , Ácaros , Tetranychidae , Animais , Controle Biológico de Vetores , Comportamento Predatório
11.
J Adv Res ; 38: 29-39, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35572395

RESUMO

Introduction: Investigation into the action mechanisms of plant secondary metabolites against pests is a vital strategy for the development of novel promising biopesticides. Scoparone (isolated from Artemisia capillaris), a renewable plant-derived bioresource, displays potent acaricidal activities against mites, but its targets of action remain unclear. Objectives: This study aimed to systematically explore the potential molecular targets of scoparone against Tetranychus cinnabarinus and provide insights to guide the future application of scoparone as an agent for the management of agricultural mite pests worldwide. Methods: The mechanism and potential targets of scoparone against mites were investigated using RNA-seq analysis; RNA interference (RNAi) assays; bioassays; and [Ca2+]i, pull-down and electrophysiological recording assays. Results: RNA-seq analysis identified Ca2+ signalling pathway genes, specifically 5 calmodulin (CaM1-5) genes and 1 each of L-, T-, N-type voltage-gated Ca2+ channel (VGCC) genes, as candidate target genes for scoparone against mites. Furthermore, RNAi and electrophysiological data showed that the CaM1- and L-VGCC-mediated Ca2+ signalling pathways were activated by scoparone. Interestingly, by promoting the interaction between CaM1 and the IQ motif (a consensus CaM-binding domain of L-VGCC), CaM1 markedly enhanced the activating effect of scoparone on L-VGCC. Pull-down assays further demonstrated that CaM interacted with the IQ motif, triggering L-VGCC opening. Importantly, mutation of the IQ motif significantly weakened CaM1 binding and eliminated the CaM1-mediated enhancement of scoparone-induced L-VGCC activation, indicating that the effect of scoparone was dependent on the CaM1-IQ interaction. Conclusion: This study demonstrates, for the first time, that the acaricidal compound scoparone targets the interface between CaM1 and L-VGCC and activates the CaM-binding site, located in the IQ motif at the L-VGCC C-terminus. This work may contribute to the development of target-specific green acaricidal compounds based on L-VGCC.


Assuntos
Acaricidas , Ácaros , Tetranychidae , Acaricidas/farmacologia , Animais , Calmodulina/química , Calmodulina/metabolismo , Calmodulina/farmacologia , Cumarínicos/farmacologia , Ácaros/metabolismo , Tetranychidae/metabolismo
12.
Exp Appl Acarol ; 86(4): 479-498, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35534782

RESUMO

Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) is a predatory mite, effective at controlling whiteflies and thrips in protected crops. However, on tomato its efficacy as a biocontrol agent is hindered, most probably by the plant trichomes and their exudates. Our aim was to characterize the response of A. swirskii to the tomato trichome exudates and identify three major detoxification gene sets in this species: cytochromes P450 (CYPs), glutathione S-transferases (GSTs) and carboxyl/cholinesterases (CCEs). Mites were exposed separately to tomato and pepper, a favourable host plant for A. swirskii, after which their transcriptional responses were analysed and compared. The de novo transcriptome assembly resulted in 71,336 unigenes with 66.1% of them annotated. Thirty-nine A. swirskii genes were differentially expressed after transfer on tomato leaves when compared to pepper leaves; some of the expressed genes were associated with the metabolism of tomato exudates. Our results illustrate that the detoxification gene sets CYPs, GSTs and CCEs are abundant in A. swirskii, but do not play a significant role when in contact with the tomato exudates.


Assuntos
Lycopersicon esculentum , Ácaros , Tisanópteros , Animais , Lycopersicon esculentum/genética , Ácaros/genética , Controle Biológico de Vetores/métodos , Comportamento Predatório , Transcriptoma
13.
Expert Rev Clin Immunol ; 18(6): 581-590, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35502686

RESUMO

INTRODUCTION: The links between allergen exposure and sensitization are complex and depend not only on the type of allergen but on various genetic and environmental factors. AREAS COVERED: This review discusses the link between allergen exposure and atopic sensitization for different types of allergens and the factors that mediate or affect this link. For the purposes of this review search of PubMed was undertaken to identify English language articles using the terms 'sensitization' and 'allergen exposure' and 'children/or adolescents.' EXPERT OPINION: Regarding food sensitization, the available data for peanuts and eggs suggest that there is a window period between 4 and 6 months of age when the introduction of these foods may limit sensitization and clinically overt allergy to the respective foods. As far as it concerns aeroallergens, it seems that there is a complex and variable relationship between mite exposure and specific sensitization especially if the exposure occurs early in life. Early exposure to dog allergens does not seem to be associated with specific sensitization; regarding cats, the results are still inconsistent. Several factors may mediate the relationship between early exposure to allergens and the development of sensitization or clinical allergy.


Assuntos
Hipersensibilidade Imediata , Hipersensibilidade , Ácaros , Adolescente , Alérgenos , Animais , Cães , Humanos , Hipersensibilidade/epidemiologia
14.
Exp Appl Acarol ; 86(4): 499-515, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35389177

RESUMO

The predatory mite Lasioseius japonicus Ehara is a newly recorded species in China that has been shown to have great potential as a biological control agent. The species is a soil-dwelling mite that is known to prey on various pests including economically important mites, fungus gnats and other terricolous arthropods. Considering that temperature is one of the most important factors affecting the population dynamics of arthropods, the development, survival and reproduction of L. japonicus were evaluated under indoor conditions at seven temperatures: 19, 22, 25, 28, 31, 34 and 37 °C, at 75% relative humidity and L0:D24 h photoperiod. The mites were fed on the cereal mite Tyrophagus putrescentiae (Schrank) and the data were analyzed using the two-sex life table. The results demonstrated that L. japonicus could complete their development and reproduce at temperatures between 19 and 34 °C, but were unsuccessful at 37 °C. Increasing temperature shortened the development time of the pre-adult stage and the average generation time (T). The life table parameters indicated that at temperatures from 22 to 31 °C the development rate and reproduction of L. japonicus were highest: at 22, 25, 28 and 31 °C the net reproduction rate (R0) was 55.5, 61.6, 61.2 and 59.0, respectively, and the average fecundity rate (F) was 81.7, 88.0, 102.0 and 86.8, respectively. The maximum values of intrinsic population growth rate (r) (0.341) and finite rate of increase (λ) (1.407) occurred at 31 °C.


Assuntos
Acaridae , Ácaros , Animais , Grão Comestível , Comportamento Predatório , Temperatura
15.
Int J Mol Sci ; 23(8)2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35457116

RESUMO

Storage mites (SM) may induce allergic respiratory symptoms in sensitized individuals, in both rural and urban settings. The relationship among specific IgE reactions to determined groups of SM allergens in the coincident asthma pheno-endotypes has not yet been investigated. We aimed to study a Precision Allergy Molecular Diagnosis (PAMD@) model to depict the SM molecular profile in individuals presenting with Type-2 inflammation, in two different (moderate and severe) asthma phenotypes. A customized PAMD@ panel, including SM allergens and their concurrent protein allergenic characterization was investigated. Mite group 2 allergens were most frequently recognized, including Lep d 2 (83.45%), followed by Gly d 2 (69.17%) and Tyr p 2 (47,37%), in 133/164 asthmatic subjects. Blo t 5 and Blo t 21 exhibited significant higher titres in both asthma groups. Although relevant mite group 2 allergens cross-reactivity is suggested, individualized sensitization patterns were relevantly identified. The present PAMD@ panel confirmed the dominance of mite group 2 allergens in moderate-to-severe T2 asthmatics. A broadly heterogeneous molecular repertoire of SM allergens was found in all subjects, regardless of their asthma severity. Blomia tropicalis deserves special attention in certain territories, as diagnostic and/or therapeutic approaches merely based on Pyroglyphidae mites may be insufficient.


Assuntos
Acaridae , Asma , Hipersensibilidade , Ácaros , Alérgenos/genética , Animais , Antígenos de Dermatophagoides , Asma/diagnóstico , Humanos , Hipersensibilidade/diagnóstico , Imunoglobulina E/genética , Fenótipo , Pyroglyphidae
16.
Pest Manag Sci ; 78(7): 3071-3079, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35437918

RESUMO

BACKGROUND: Quantifying how chemical tolerance of pest arthropods varies with temperature is important for understanding the outcomes of chemical control, for measuring and monitoring resistance, and for predicting how pesticide resistance will evolve under future climate change. We studied the redlegged earth mite, Halotydeus destructor (Tucker), a winter-active invasive agricultural pest in Australia. Using a replicated block experiment, we tested the effect of different thermal conditions on the expression of chemical tolerance to a pyrethroid and two organophosphates. Our chemical bioassays were conducted on two redlegged earth mite populations: one possessed organophosphate resistance, whilst the other was susceptible to pesticides. Mites were first acclimated at cool (4 °C) and warm (14 °C) conditions and then exposed to pesticides in both cool (11 °C) and warm (18 °C) test conditions. RESULTS: Warm test conditions generally reduced chemical tolerance to all pesticides relative to cool test conditions. Median lethal dose (LD50 ) values of mites tested under cool conditions were 1.12-3.57-fold greater than of mites tested under warm conditions. Acclimation had a variable and small impact on chemical responses. Thermal factors (ratio between test temperatures) were similar between populations for each active ingredient. Despite reduced chemical tolerances under warm test conditions for individual mite populations, resistance factors (ratio between resistant and susceptible mite populations) were relatively consistent. CONCLUSION: Our data provides context for prior theoretical work demonstrating climatically constrained pesticide resistances in Australian redlegged earth mites. Estimates of temperature dependent toxicity measured in this study may be useful in parameterizing models of redlegged earth mite control under an increasingly warm and more variable climate. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Ácaros , Praguicidas , Piretrinas , Animais , Austrália , Ácaros/fisiologia , Organofosfatos/farmacologia , Praguicidas/farmacologia , Piretrinas/farmacologia , Temperatura
18.
PLoS One ; 17(4): e0266335, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35446869

RESUMO

Polyphagotarsonemus latus Banks is considered a polyphagous pest of diverse agricultural and ornamental crops of global economic significance. Its distribution, host range, variety of symptoms, morphological differences, chaetotaxy and several ontogeny reports have advanced the idea of P. latus as a species complex. Correct pest identification leads to suitable control treatment. Therefore, the objective of this study was the identification of mites collected in two different geographic regions in Mexico (Chiapas and Guanajuato) that had been tentatively designated as Polyphagotarsonemus sp. Biometric differences on the morphology of adults as well the genetic variability were determined by taxonomical and molecular (mitochondrial COI gene) characterization techniques. The identity of the mites from both populations was confirmed as P. latus based on taxonomic characters. Biometric parameter variations were found between both populations (70.58% and 53.84% for females and males, respectively). The average sequenced fragment size was 447 bp (both populations). A homology search against six P. latus sequences available in the GenBank database revealed that sequence KM580507.1 (from India) shows 83.0-86.41% and 99.26-99.52% similarity with the sequences from Guanajuato and Chiapas, respectively. Molecular data indicated a significant divergence between the populations. The genetic distance demonstrates the population from Chiapas has a higher genetic correspondence (0.010) to the sequence from India (KM580507.1) whereas the population from Guanajuato is more distant (0.191). The genetic distance between the populations of this study and other GenBank sequences is even larger. We consider our results strengthen the hypothesis of P. latus consisting of a species-complex. However, it is essential to extend the study to other regions including its country of origin (Sri Lanka), and to include ultrastructural features.


Assuntos
Ácaros , Agricultura , Animais , Feminino , Especificidade de Hospedeiro , Índia , Masculino , México , Ácaros/genética
19.
Environ Pollut ; 305: 119290, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35436506

RESUMO

Massive use of pesticides in conventional agriculture leads to accumulation in soil of complex mixtures, triggering questions about their potential ecotoxicological risk. This study assessed cropland soils containing pesticide mixtures sampled from conventional and organic farming systems at La Cage and Mons, France. The conventional agricultural field soils contained more pesticide residues (11 and 17 versus 3 and 11, respectively) and at higher concentrations than soils from organic fields (mean 6.6 and 10.5 versus 0.2 and 0.6 µg kg-1, respectively), including systemic insecticides belonging to neonicotinoids, carbamate herbicides and broad-spectrum fungicides mostly from the azole family. A risk quotient (RQi) approach evaluated the toxicity of the pesticide mixtures in soil, assuming concentration addition. Based on measured concentrations, both conventional agricultural soils posed high risks to soil invertebrates, especially due to the presence of epoxiconazole and imidacloprid, whereas soils under organic farming showed negligible to medium risk. To confirm the outcome of the risk assessment, toxicity of the soils was determined in bioassays following standardized test guidelines with seven representative non-target invertebrates: earthworms (Eisenia andrei, Lumbricus rubellus, Aporrectodea caliginosa), enchytraeids (Enchytraeus crypticus), Collembola (Folsomia candida), oribatid mites (Oppia nitens), and snails (Cantareus aspersus). Collembola and enchytraeid survival and reproduction and land snail growth were significantly lower in soils from conventional compared to organic agriculture. The earthworms displayed different responses: L. rubellus showed higher mortality on soils from conventional agriculture and large body mass loss in all field soils, E. andrei showed considerable mass loss and strongly reduced reproduction, and A. caliginosa showed significantly reduced acetylcholinesterase activity in soils from conventional agriculture. The oribatid mites did not show consistent differences between organic and conventional farming soils. These results highlight that conventional agricultural practices pose a high risk for soil invertebrates and may threaten soil functionality, likely due to additive or synergistic "cocktail effects".


Assuntos
Artrópodes , Ácaros , Oligoquetos , Praguicidas , Poluentes do Solo , Acetilcolinesterase , Agricultura , Animais , Invertebrados , Praguicidas/toxicidade , Reprodução , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
20.
Comp Med ; 72(2): 113-121, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35379379

RESUMO

Ornithonyssus bacoti, commonly known as the tropical rat mite, is a zoonotic ectoparasite that occasionally infests research rodent colonies. Most infestations have been attributed to wild rodents that harbor the mite and spread it to research animals, often during building construction or other activity that disrupts wild rodent populations. Although infestation may be clinically silent, severe outbreaks have been reported to cause pruritis, dermatitis, decreased reproductive performance, and anemia in rodents. In mid-2020, our institution experienced increased activity of wild mice, which were found to be infested with O. bacoti, diagnosed by microscopic exam and confirmed by fur swab PCR analysis. We elected to add O. bacoti to our quarterly health monitoring exhaust air dust (EAD) testing PCR panel, increase wild mouse control measures, and treat the environment with a sustained-release synthetic pyrethroid spray in an attempt to prevent colony animal infestation. Initial quarterly EAD health monitoring results in September of 2020 were negative for O. bacoti. However, in early 2021, multiple IVC racks tested positive for O. bacoti at quarterly testing. Treatment consisted of providing permethrin-soaked nesting material and surface spray treatment of the room and hallway with a sustained-release synthetic pyrethroid. Historically in the literature, O. bacoti outbreaks of research mice were not identified until mite burden was high enough to cause dermatitis on animal care workers. Due to modern molecular diagnostics and proactive PCR-based health monitoring surveillance, we were able to identify the outbreak earlier than would have otherwise been possible. To the best of our knowledge, this is the first report to successfully identify O. bacoti using environmental health monitoring PCR techniques. This outbreak demonstrates the importance of screening for O. bacoti in facilities with the potential for wild rodent infestation and highlights unique considerations when managing O. bacoti infestations. In addition, a novel permethrin-soaked enrichment item was developed for cage-level treatment.


Assuntos
Dermatite , Infestações por Ácaros , Ácaros , Piretrinas , Animais , Preparações de Ação Retardada , Dermatite/etiologia , Camundongos , Infestações por Ácaros/diagnóstico , Infestações por Ácaros/epidemiologia , Infestações por Ácaros/prevenção & controle , Técnicas de Diagnóstico Molecular , Permetrina , Roedores
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