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a monitoring study on the prevalence of dermatophilosis and parafilariosis in cattle in a smallholder semi-arid farming area in zimbabwe.the prevalences of dermatophilosis and parafilariosis were monitored for one year in cattle in sanyati, a semi-arid smallholder farming area in zimbabwe. the prevalence of dermatophilosis differed (p < 0.05) with season and among calves, cows, oxen and bulls. in bulls and cows, dermatophilosis lesions were localized mainly to the inguinal regions and between the front limbs. the prevalence and morbidity of dermatophilosis infection were significantly higher (p < 0.05) during the wet season than ...200415080537
species of ticks on camels and their seasonal population dynamics in eastern ethiopia.a study was conducted to identify the species of ticks found on camels (camelus dromedarius) and their seasonal population dynamics in eastern ethiopia. collection and identification of the ticks were undertaken at 2-month intervals from december 1997 to august 1999. on each occasion, all the visible adult ticks were collected from one side of the body of each of the same 17 camels. the most abundant species of ticks on the camels were rhipiephalus pulchellus (85.2%), hyalomma dromedarii (5.9%), ...200415080539
detection of pathogenic ehrlichia in ticks collected at acquisition sites of human ehrlichiosis in missouri.we collected 385 ticks from sites in missouri associated with human monocytic ehrlichiosis. using pcr, we detected e. chaffeensis or e. ewingii in 2 of 19 pools of adult amblyomma americanum, 0 of 32 pools of dermacentor variabilis, and 6 (18%) of 39 pools of unspeciated nymphal ticks from 3 of 6 sites associated with disease and one site not associated with disease. we also detected a variant of a. phagocytophila in one nymph pool.200415119113
the distribution and ecological 'preferences' of the tick amblyomma cajennense (acari: ixodidae), an ectoparasite of humans and other mammals in the americas.the distribution and ecological 'preferences', in the nearctic and neotropical regions, of the prominent, pathogen-carrying tick amblyomma cajennense (fabricius) were reviewed, on the basis of the published literature, satellite imagery, and the examination of several tick collections. the tick has been collected from the southern u.s.a. (texas and florida) to northern argentina, but is probably absent from uruguay and southern brazil (the few records of the species in these areas probably repre ...200415119974
glycerophosphodiester phosphodiesterase gene (glpq) of borrelia lonestari identified as a target for differentiating borrelia species associated with hard ticks (acari:ixodidae).a glpq ortholog was identified in dna from borrelia lonestari-positive amblyomma americanum, providing further evidence that b. lonestari is more closely related to the relapsing fever group spirochetes than to borreliae that cause lyme disease. this finding provides a basis for developing diagnostic assays to differentiate species of borrelia transmitted by hard ticks.200415131225
disease survey of free-ranging grey brocket deer (mazama gouazoubira) in the gran chaco, bolivia.samples from 17 free-ranging hunter-killed grey brocket deer (mazama gouazoubira) in the gran chaco, bolivia, were collected during june-august 1999. all 17 deer appeared to be in good condition at the time of death. gross necropsies were performed, serum was collected for serologic evaluation of selected infectious disease agents, and feces and ectoparasites were collected for evaluation of internal and external parasites. serologic tests were positive for antibodies against bovine respiratory ...200415137493
monthly dynamics of ticks (acari:ixodida) infesting n'dama cattle in the republic of guinea.the occurrence of ixodid ticks on n'dama cattle was studied in the republic of guinea between june 1994 and may 1995. monthly tick collections were performed on 80 animals from 14 villages located in dabola, kouroussa and dinguiraye prefectures. a total of 19,804 ticks was collected and classified using standard taxonomic keys. the following tick species were identified: amblyomma variegatum, hyalomma marginatum rufipes, hyalomma trunctum, hyalomma nitidum, rhipicephalus lunulatus, rhipicephalus ...200415139086
life cycle of amblyomma cooperi (acari: ixodidae) using capybaras (hydrochaeris hydrochaeris) as hosts.the life cycle of amblyomma cooperi was evaluated under laboratory conditions testing different host species. larval infestations were performed on chickens (gallus gallus) and capybaras (hydrochaeris hydrochaeris). nymphal infestations were performed on g. gallus, h. hydrochaeris, guinea pigs (cavia porcellus) and wild mice (calomys callosus). infestations by adult ticks were performed only on capybaras. all free-living stages were observed in darkness at 27 degrees c and rh 85%. capybaras were ...200415139274
ehrlichia ruminantium seroprevalence in domestic ruminants in ghana; i. longitudinal survey in the greater accra region.serum samples collected monthly over a 34-month period from cattle, sheep and goats in the greater accra region of ghana were tested for antibodies to ehrlichia (previously cowdria) ruminantium, the causative agent of heartwater, by polyclonal competitive elisa (pc-elisa). maternal antibodies, detected in about half of animals followed from under 1 month old, declined to negative levels within 2-4 months. amblyomma variegatum tick vectors were present on livestock in rural areas throughout the y ...200415145496
[relative abundance of amblyomma spp. (acari: ixodidae) in bovines (bos taurus and b. indicus) from costa rica].the research describe the big amount of ticks of the amblyomma genus, found on bovines through monthly samplings carried out in ten farms in eight ecological zones (ez) of costa rica. ticks larger than 4 mm were picked up from the right side of the animals during the visit. the study compiled meteorological information for some farms located in the experiment, showing that the most fluctuant variable is rainfall. the most important amblyomma species found was a. cajennense. amblyomma nymphs were ...200315162737
effects of 20-hydroxyecdysone and other hormones on egg development, and identification of a vitellin-binding protein in the ovary of the tick, amblyomma hebraeum.partially fed adult female amblyomma hebraeum ticks were injected with 20-hydroxyecdysone (20e; up to 43 microg/g body weight (bw)), juvenile hormone iii (jh iii; up to 100 microg/g bw), bovine insulin (up to 2000 mu/g bw), or triiodothyronine (up to 200 ng/g bw) in an attempt to stimulate vitellogenesis. of these, only 20e stimulated synthesis and release of vitellogenin (vg). immunoblot analysis revealed that vg-synthesis occurred in the fat body. however, consistent with earlier observations ...200415183281
development of a novel self-medicating applicator for control of internal and external parasites of wild and domestic animals.four trials, three in the united states and one in south africa, were conducted to evaluate the potential value of a novel self-medicating applicator in the passive control of gastrointestinal nematodes in cattle and deer, and of files and ticks on cattle using oil-based treatments. the results of the trials demonstrated that this applicator is an effective and practical device for the passive treatment of both deer and cattle for trichostrongyle infections using the endectocide, moxidectin (cyd ...200415185574
phylogenetic analysis of the francisella-like endosymbionts of dermacentor ticks.bacterial endosymbionts with significant homology to francisella tularensis (gamma-proteobacteria) have been described from at least five species of ticks in three different genera, including two north american dermacentor species [d. andersoni stiles and d. variabilis (say)]. the evolutionary relationships among the francisella-like endosymbionts (fle) from different hosts and between fle and the arthropod-borne pathogen f. tularensis are not known. a 1,169-base fragment of the 16s rdna and a 7 ...200415185926
study of the seasonal dynamics, life cycle, and host specificity of amblyomma aureolatum (acari: ixodidae).in the first part of this study, monthly infestation by ticks was evaluated on dogs from december 2000 to november 2002 in the rural area of taiaçupeba, são paulo. adults of amblyomma aureolatum (pallas) were found on dogs in all months, with a mean prevalence per month of 46.9 +/- 15.7% (range, 25-80%). the mean tick relative abundance per month was 2.4 +/- 2.7 ticks (range, 0.5-14 ticks), and the mean tick mean intensity per month was 4.7 +/- 4.2 ticks (range, 1.5-23.3 ticks). no a. aureolatum ...200415185932
molecular evidence for a spotted fever group rickettsia species in the tick amblyomma longirostre in brazil.two amblyomma longirostre adult male ticks were collected from a brazilian porcupine coendou prehensilis l. in the state of rondonia, western amazon, brazil. the two ticks were pooled for dna extraction and tested for the presence of rickettsial dna by amplifying portions of the glta, 17-kda, ompa, and ompb rickettsial genes by polymerase chain reaction (pcr). portions of the four genes were amplified from the sample and subsequently sequenced. these results indicated the presence of a rickettsi ...200415185961
human otoacariasis: a retrospective study from an area of sri lanka.intra-aural ticks were present in 870 (15.2%) of 5714 patients who reported with ear-related complaints to the ear, nose and throat ward at ratnapura hospital, sabaragamuwa province, sri lanka, from january 2000 to december 2001. a retrospective study of 383 of these otoacariasis cases showed that the majority (70.8%) of surgically-removed ticks were nymphal amblyomma integrum, together with nymphal and adult rhipicephalus haemaphysaloides, r. sanguineus, hyalomma brevipunctata, h. marginatum, a ...200415186938
an updated list of the ticks of ghana and an assessment of the distribution of the ticks of ghanaian wild mammals in different vegetation zones.twenty one species of ticks belonging to five genera of the family ixodidae (order acari, sub-order ixodida) - amblyomma, haemaphysalis, hyalomma, ixodes and rhipicephalus (including the sub-genus rhipicephalus (boophilus)) - were collected from 1260 mammals, representing 29 species, 14 families and 6 orders, in four vegetation zones in ghana during the period 1971-1978. four other species were collected from humans in 1977. in all, eight species appeared to be new records for ghana: amblyomma t ...200415191626
a proteomics approach to characterizing tick salivary secretions.the saliva of ticks contains a complex mixture of bioactive molecules including proteins that modulate host responses ensuring successful feeding. the limited amount of saliva that can be obtained from ticks has hampered characterization of salivary proteins using traditional protein chemistry. recent improvements in two-dimensional gel electrophoresis, mass spectrometry, and bioinformatics provide new tools to characterize small amounts of protein. these methods were employed to characterize sa ...200415198089
cutaneous hypersensitivity induced in rabbits by extracts of the tick amblyomma cajennense (acari: ixodidae).the cutaneous hypersensitivity test was used to correlate host resistance to ticks and type of reactions elicited by aomblyomma cajennense (fabricius, 1787) tick extract in rabbits. rabbits were divided into 3 groups of 2 animals each: naive, pre-infested and control. cutaneous hypersensitivity was induced by intradermal inoculation of 25 microg extract in 0.03 ml of phosphate buffered saline (pbs) in rabbit ears. control rabbits were inoculated with pbs only. the ear thickness was measured with ...200415214693
cross-reactivity between antigens from amblyomma cajennense and a. hebraeum (acari: ixodidae).laboratory animals exposed to feeding ticks develop resistance which is reflected by a decline in tick engorgement weight, egg-laying by adults and reduced egg viability. serum antibodies from these hosts and their reaction with tick antigens have been detected by different methods, including precipitation techniques, immunofluorescent techniques, elisa and western blots. however, little is known about the effects of antibodies on ticks that engorge on resistant hosts, or which tissues of the ti ...200415214694
spotted fever group rickettsiae from ticks captured in sudan.ticks were collected from ruminants in various areas of sudan in 1998 and 2000. primer pairs of rickettsial citrate synthase gene (glta) and a spotted fever group (sfg) rickettsial 190-kda surface antigen gene (rompa), respectively, were used for identification. polymerase chain reaction (pcr)-positive products were used for dna sequencing. the glta gene was detected in 55% of the ticks examined (57/104). among the 57 ticks studied, 19 were positive for the rompa gene. thus, 18% of the ticks exa ...200415218219
effects of granular carbaryl application on sympatric populations of ixodes scapularis and amblyomma americanum (acari: ixodidae) nymphs.a single application of granular carbaryl approaching the lowest recommended rate to the shrub layer of a forested area in late spring significantly reduced the abundance of ixodes scapularis say nymphs throughout their peak activity period, but had little effect on amblyomma americanum l. nymphs. factors influencing the efficacy of the application are discussed. the possible explanations for the lack of efficacy of granular carbaryl against a. americanum, including behavior, formulation, and ap ...200015218915
a new type of antimicrobial protein with multiple histidines from the hard tick, amblyomma hebraeum.a novel 11 kda antimicrobial protein, named as hebraein, and having a unique amino acid sequence, was purified from the hemolymph of fed female amblyomma hebraeum ticks. a full-length cdna clone encoding hebraein was isolated from a cdna library made from tick synganglia. hebraein consists of 102 amino acids, including 6 cysteine residues; has 9 histidines in its c-terminal domain that are mainly present as hx repeats; and has no significant similarity to any known protein. the secondary structu ...200415247144
ectoparasites of gray squirrels in two different habitats and screening of selected ectoparasites for bartonellae.gray squirrels, sciurus carolinensis, were livetrapped in 2 different habitat types, woodland (67 squirrels) and parkland (53 squirrels), in southeastern georgia. ectoparasites were recovered from anesthetized squirrels and compared between hosts from the 2 habitats. because of the absence of low vegetation in parkland habitats, it was hypothesized that the ectoparasite fauna, especially ticks and chiggers, would be more diverse on woodland squirrels. the results were generally in agreement with ...200415270090
ticks (acari: ixodidae) parasitizing wild carnivores in phu khieo wildlife sanctuary, thailand.ixodid ticks were collected and identified from 8 wild carnivore species in phu khieo wildlife sanctuary, northeastern thailand. six tick species belonging to 4 genera were recovered and identified from 132 individuals. these included amblyomma testudinarium (n = 36), haemaphysalis asiatica (n = 58), h. hystricis (n = 31), h. semermis (n = 3), rhipicephalus haemaphysaloides (n = 3), and ixodes granulatus (n = 1). leopard cats (prionailurus bengalensis) (n = 19) were infested with 4 tick species, ...200415270119
amblyomma cajennense ticks induce immediate hypersensitivity in horses and donkeys.since host immune reaction to ticks interferes with tick-borne pathogen transmission, it is important to recognize naturally occurring tick-host immune relationships to better understand the epidemiology of such infectious diseases. amblyomma cajennense is an important tick-borne disease vector in the neotropical region and horses maintain it in domestic environments. in the present work intradermal testing of a. cajennense tick exposed horses and donkeys using crude tick antigens was used to ev ...200415285143
first record of immature stages of amblyomma tigrinum (acari: ixodidae) on wild birds in chile.for the first time, larvae and nymphs of amblyomma tigrinum ticks were found on three species of wild birds (zenaida auriculata, callipepla californica and nothoprocta perdicaria) in chile. a significant higher number of a. tigrinum was found on fledglings of z. auriculata and n. perdicaria than on adults of these species of birds. a significant higher number was also observed on n. perdicaria living in non-irrigated areas as compared with irrigated areas. infestation levels were 6.5, 6.3 and 10 ...200415285147
disease agents in amblyomma americanum from northeastern georgia.amblyomma americanum (lone star tick) is known or suspected to vector several organisms that are implicated as human pathogens, including ehrlichia chaffeensis, e. ewingii, and borrelia lonestari. these three agents have also been detected in white-tailed deer (odocoileus virginianus). because northeastern georgia has a high abundance of both lone star ticks and white-tailed deer, and one of these organisms, e. chaffeensis, is already known to be endemic in the area, we assayed individual adult ...200415311471
ehrlichia prevalence in amblyomma americanum, central texas. 200415338551
water relations in eggs of the lone star tick, amblyomma americanum, with experimental work on the capacity for water vapor absorption.this study shows that water stress is not countered in eggs of the lone star tick, amblyomma americanum (l.), using water vapor, and suggests involvement of liquid water as a developmental cue. eggs fail to maintain an equilibrium water content in subsaturated air, hence, gain not equal to loss, with net water losses occurring at relative humidities near saturation and these eggs exhibit a three-fold drop in viability, but not incubation period, as compared to eggs held in saturated air. amblyom ...200415347026
susceptibility of mosquito and tick cell lines to infection with various flaviviruses.the genus flavivirus consists of more than 70 virus species and subtypes, the majority of which are transmitted by mosquitoes or ticks, although some have no known vector (nkv). the ability of these viruses to infect cultured cells derived from mosquito or tick species offers a useful insight into the suitability of such vectors to harbour and replicate particular viruses. we undertook a comparative study of the susceptibility of mammalian vero cells, a clonal mosquito cell line (c6/36) and rece ...200415347394
some observations on the sero-prevalence of heartwater and tick infestation in zambian goats.a survey was carried out to define the distribution of heartwater in goats that originated from six districts in communal grazing semi-arid areas of zambia. a total of 181 samples (40.1%) out of 451 serum samples from adult goats were positive for ehrlichia ruminantium antibodies after screening using indirect map-1b antigen elisa technique with statistically significant differences (p < 0.01) between the six districts. out of 1 036 adult goats examined for tick infestation, 105 were infested by ...200415373339
detection of rickettsia africae in patients and ticks along the coastal region of cameroon.rickettsia africae was identified in seven (6%) of 118 patients with acute fevers of unknown etiology proven not to be malaria or typhoid fever from clinics along the coastal region of cameroon by polymerase chain reaction (pcr) amplification and sequencing of the citrate synthase (glta) and outer membrane protein a (ompa) genes of rickettsia. the majority (71%) of the patients were female. clinical manifestations included fever (100%), headache (71%), myalgia (71%), arthralgia (43%), pulmonary ...200415381820
serological characteristics of a pathogenic rickettsia occurring in amblyomma maculatum. 194915398100
[amblyomma diemeniae, a new reptilian tick from australia, with observations on variant formations of the clava in the genus amblyomma]. 195015431890
[rickettsia africae, the agent of african tick-bite fever: an emerging pathogen in the west indies and reunion island (indian ocean)].rickettsia africae is the agent of african tick bite fever, an emerging disease transmitted by amblyomma ticks in sub-saharan africa. in 1998, we reported the first documented case of r. africae in the new world, in a patient who had returned from guadeloupe. in order to confirm the presence of r. africae in the west indies, entomologic surveys were conducted from 1999 to 2003 to collect amblyomma, which are considered as potential vectors and reservoirs of the bacteria. ticks were used as epide ...200415462202
amblyomma variegatum and acute bovine dermatophilosus. 198615462727
morphological characterization of the ovary and vitellogenesis dynamics in the tick amblyomma cajennense (acari: ixodidae).in this work we describe the internal morphology of the female reproductive system of the cayenne tick amblyomma cajennense. this system is represented by a panoistic ovary, which lacks nurse cells in the germarium. this ovary consists of a single tube, in which a large number of oocytes develop asynchronously, thus accompanying the processes of yolk deposition in the oocytes. the oocytes were classified into stages that varied from i to v, according to: cytoplasm appearance, presence of the ger ...200415482894
rickettsia parkeri in amblyomma triste from uruguay.our goal was to detect whether spotted fever group rickettsia are found in the suspected vector of rickettsioses, amblyomma triste, in uruguay. rickettsia parkeri was detected in a. triste, which suggests that this species could be considered a pathogenic agent responsible for human rickettsioses in uruguay.200415496258
amblyomma americanum salivary gland homolog of nsec1 is essential for saliva protein secretion.soluble n-ethylmaleimide-sensitive factor attachment protein receptor proteins assemble in tight core complexes which promote fusion of carrier vesicles with target compartments. members of this class of proteins are expressed in all eukaryotic cells and distributed in distinct subcellular compartments. all vesicle transport mechanisms known to date have an essential requirement for a member of the sec1 protein family, including the nsec1 in regulated exocytosis. a homolog of nsec1 was cloned an ...200415504350
a thrombin inhibitor from the ixodid tick, amblyomma hebraeum.a novel thrombin inhibitor named amblin was identified from the haemolymph of the ixodid (hard) tick, amblyomma hebraeum, and the coding cdna was isolated from a tick cdna library. this cdna codes for a preprotein of 166 amino acids, including a predicted signal peptide composed of 15 amino acids n-terminal to the mature amblin. the 151-amino-acid mature amblin contains 14 cysteines and two kunitz-like domains. it displays high sequence similarity with a tissue factor pathway inhibitor (tfpi), i ...200415527983
characterization of spotted fever group rickettsiae in flea and tick specimens from northern peru.evidence of spotted fever group (sfg) rickettsiae was obtained from flea pools and individual ticks collected at three sites in northwestern peru within the focus of an outbreak of febrile disease in humans attributed, in part, to sfg rickettsia infections. molecular identification of the etiologic agents from these samples was determined after partial sequencing of the 17-kda common antigen gene (htra) as well as pairwise nucleotide sequence homology with one or more of the following genes: glt ...200415528680
borrelia species in host-seeking ticks and small mammals in northern florida.the aim of this study was to improve understanding of several factors related to the ecology and environmental risk of borrelia infection in northern florida. small mammals and host-seeking adult ticks were collected at several sites, and specimens were tested for the presence of borrelia species, primarily by pcr amplification. tissues from some vertebrates and ticks were initially cultured in bsk-h medium to isolate spirochetes, but none were recovered. however, comparison of partial flagellin ...200415528699
ehrlichia chaffeensis (rickettsiales: ehrlichieae) infection in amblyomma americanum (acari: ixodidae) at aberdeen proving ground, maryland.human monocytic ehrlichiosis (hme) is a sometimes fatal, emerging tick-borne disease caused by the bacterium ehrlichia chaffeensis. it is frequently misdiagnosed because its symptoms mimic those of the flu. current evidence indicates that amblyomma americanum (l.), the lone star tick, is the major vector of hme. to determine if e. chaffeensis is present in ticks at aberdeen proving ground, md, questing a. americanum ticks were collected from 33 sites. nucleic acid was extracted from 34 adult and ...200015535577
seasonal distribution and abundance of ticks (acari: ixodidae) in northwestern florida.a 2-yr study was conducted in a northwestern florida state park and recreation area to determine tick species composition, seasonal abundance, and spatial distribution. risk of tick attachment to park visitors was also assessed relative to tick abundance from several habitats. tick collections consisted of weekly cloth drag samples obtained from ground and emergent vegetation along a deer trail, a walking trail located in a 3-mo-old control burned area of forest, a nonburned walking trail, picni ...200015535590
[random amplified polymorphic dna analysis of the genomes among 7 species of ticks].to study genomic polymorphic dna and genetic distance of 7 species of ticks.200415587156
nested pcr for detection and genotyping of ehrlichia ruminantium: use in genetic diversity analysis.ehrlichia ruminantium, the agent of cowdriosis transmitted by amblyomma ticks, presents an extensive genetic and antigenic diversity of key importance for vaccine formulation. two means of nested polymerase chain reaction (pcr) targeting were developed to conduct molecular epidemiology studies in the caribbean and africa. the first used a conserved dna fragment for detection of the pathogen in animals and vectors, and the second relied on the polymorphic map1 gene for genotyping. as compared to ...200415604477
successful infestation by amblyomma pseudoconcolor and a. cooperi (acari: ixodidae) on horses.the host relationships for most species of the genus amblyomma are poorly known in brazil. the ability of a. pseudoconcolor and a. cooperi to successfully feed on horses was investigated during ongoing research on the life cycle of these two species, which are primarily associated with wildlife. results of these experiments suggest that horses are potential hosts for the adult stages of both species.200415604498
the caribbean amblyomma program: some ecologic factors affecting its success.the caribbean amblyomma program has been operational for 8 years. however, owing to funding availability, some islands did not commence eradication activities until late 1997. during the past 2 years, 6 of the 9 islands (st. kitts, st. lucia, anguilla, montserrat, barbados, and dominica) under the program have attained the status of provisional freedom from the tropical bont tick (tbt). there are several administrative and technical reasons why the attainment of the program goals took longer tha ...200415604510
an in vitro larval immersion microassay for identifying and characterizing candidate acaricides.we have optimized a larval immersion microassay (lim) that offers superior sensitivity, flexibility to accommodate multiple formulations, and a robust capability for rapidly screening many compounds with a minimal requirement of test article for evaluation. dose-response studies were conducted for representative members from the organophosphate, pyrethroid, pyrazole, carbamate, macrocyclic lactone, and formamidine chemistries against amblyomma americanum (l.). time-response experiments revealed ...200415605642
rickettsia bellii and rickettsia amblyommii in amblyomma ticks from the state of rondônia, western amazon, brazil.this study evaluates the rickettsial presence in amblyomma ticks from eight areas of the amazon forest in rondônia, brazil. the following tick species (number in parentheses) were examined: amblyomma ovale koch (121), amblyomma cajennense (f.) (41), amblyomma naponense (packard) (36), amblyomma scalpturatum neumann (35), amblyomma oblongoguttatum koch (30), amblyomma incisum neumann (27), amblyomma rotundatum koch (16), amblyomma coelebs neumann (10), and amblyomma humerale koch (6). ticks were ...200415605647
detection of ehrlichia chaffeensis in adult and nymphal amblyomma americanum (acari: ixodidae) ticks from long island, new york.the lone star tick, amblyomma americanum (l.), has increased in abundance in several regions of the northeastern united states, including areas of long island, ny. adult and nymphal stage a. americanum collected from several sites on long island were evaluated for infection with ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis (hme), by using a nested polymerase chain reaction assay. fifty-nine (12.5%) of 473 adults and eight of 113 pools of five nymphs each (estimated ...200415605650
susceptibility of mice (mus musculus) to repeated infestation with amblyomma americanum (acari: ixodidae) ticks.laboratory mice, mus musculus (l.), balb/c strain, were assessed for their ability to develop resistance to repeated infestation by amblyomma americanum (l.) ticks. mice were infested five consecutive times with a. americanum nymphs. no decrease in tick viability was seen after five infestations, suggesting that balb/c mice do not develop immune-mediated resistance to a. americanum. in contrast, tick viability was significantly reduced in the second infestation of a new zealand white rabbit, a l ...200415605656
microbiologic evaluation of patients from missouri with erythema migrans.borrelia lonestari infects amblyomma americanum, the tick species that is the most common cause of tick bites in southeast and south-central united states, and this spirochete has been detected in an erythema migrans (em)-like skin rash in 1 patient. therefore, b. lonestari is considered to be a leading candidate for the etiologic agent of em in this region.200515668867
evaluation of immunocompetent and immunocompromised mice (mus musculus) for infection with ehrlichia chaffeensis and transmission to amblyomma americanum ticks.experiments on the natural history of ehrlichia chaffeensis, the agent of human monocytic ehrlichiosis (hme), would be facilitated by the availability of a laboratory animal model for transmission to vector ticks. five strains of mice were evaluated for their susceptibility to infection with e. chaffeensis and transmission competence: c57bl/6 mice, inducible nitric oxide synthase (inos) deficient mice, mhc i deficient (beta2m /) mice, mhc ii deficient mice (abb /), and b and t cell deficient (ra ...200415671738
lack of susceptibility of guinea pigs and gerbils to experimental infection with ehrlichia chaffeensis.guinea pigs and mongolian gerbils were experimentally infected with ehrlichia chaffeensis (st. vincent strain, 10 passages in vitro). the infection was monitored by serial blood sampling for pcr and by xenodiagnosis with amblyomma americanum larvae. exposure to the pathogen was confirmed using serology. neither guinea pigs nor gerbils were susceptible to infection with e. chaffeensis, and ticks fed upon these animals did not become infected with the pathogen.200415682515
molecular differentiation of metastriate tick immatures.hard ticks, family ixodidae, are divided into two groups, the metastriata and the prostriata, based on morphological differences. in the united states, there are four medically important genera of the ixodidae: ixodes, amblyomma, dermacentor, and rhipicephalus. ixodes is the only genus in and representative of the prostriata, whereas the latter three genera are members of the metastriata. all developmental stages of the prostriata can be easily differentiated from the metastriata using morpholog ...200415682516
an attenuated ehrlichia ruminantium (welgevonden stock) vaccine protects small ruminants against virulent heartwater challenge.heartwater is a tick-borne disease of ruminants caused by the intracellular rickettsia ehrlichia ruminantium. the only commercially available immunization procedure involves infecting animals with cryopreserved sheep blood containing virulent e. ruminantium organisms, followed by treatment with tetracyclines when fever develops. the virulent welgevonden stock of e. ruminantium was attenuated by continuous propagation of the organisms in a canine macrophage-monocyte cell line (dh82), followed by ...200515705474
preliminary survey of ticks (acari: ixodidae) on cattle in northern sudan.in a cross sectional survey conducted during the period june 2001 to july 2002, the geographical distribution of ticks on cattle in the sudan was determined. seventeen locations were surveyed from northern, central, eastern, western, blue nile and white nile provinces. total body collections of ticks were made from 20 cattle at each location. four tick genera and 11 species were identified. the tick species collected included amblyomma lepidum, amblyomma variegatum, boophilus decoloratus, hyalom ...200415732459
borreliacidal activity of saliva of the tick amblyomma americanum.amblyomma americanum (linneaus) (acari: ixodidae), an important tick vector of human and animal disease, is not a competent vector of the bacterial agent of lyme disease, borrelia burgdorferi, although its range overlaps the geographical distribution of lyme disease within the united states. a possible mechanism that could prevent acquisition of b. burgdorferi spirochetes from infected hosts is the toxic effect of a. americanum saliva on b. burgdorferi. the data presented here indicate that afte ...200515752182
repellency of deet and ss220 applied to skin involves olfactory sensing by two species of ticks.responses of host-seeking nymphs of the blacklegged tick, ixodes scapularis say and lone star tick, amblyomma americanum (linnaeus) (acari: ixodidae) to the repellents n,n-diethyl-3-methylbenzamide (deet) and (1s, 2's)-2-methylpiperidinyl-3-cyclohexene-1-carboxamide (ss220) were studied using fingertip laboratory bioassays. ethanol solutions of both compounds applied to the skin strongly repelled both species of ticks at 0.8 and 1.6 micromole of compound/cm2 skin. the ticks were also repelled wh ...200515752184
improving the specificity of 16s rdna-based polymerase chain reaction for detecting borrelia burgdorferi sensu lato-causative agents of human lyme disease.16s rdna sequences of borrelia burgdorferi sensu lato were aligned with the 16s rdna sequences of borrelia hermsii, borrelia turicatae, and borrelia lonestari in order to identify primers that might be used to more specifically identify agents of human lyme disease in ticks in human skin samples.200515752343
rickettsial infection in animals and brazilian spotted fever endemicity.we compared the rickettsial infection status of amblyomma cajennense ticks, humans, dogs, and horses in both brazilian spotted fever (bsf)-endemic and -nonendemic areas in the state of sao paulo, brazil. most of the horses and few dogs from bsf-endemic areas had serologic titers against rickettsia rickettsii antigens. in contrast, no dogs or horses from bsf-nonendemic areas had serologic titers against r. rickettsii antigens, although they were continually exposed to a. cajennense ticks. all hum ...200515752445
an opioid peptide from synganglia of the tick, amblyomma testindinarium.an opioid peptide, which shares similarity with mammalian hemorphins, has been identified from the synganglia (central nervous system) of the hard tick, amblyomma testindiarium. its primary sequence was established as lvvypwtkm that contains a tetrapeptide sequence tyr-pro-trp-thr of hemorphin-like opioid peptides. by hot-plate bioassay, the purified peptide and synthetic peptide displayed dose-related antinociceptive effect in mice, as observed for other hemorphin-like opioid peptides. this is ...200415752574
ticks (acari: ixodoidea: argasidae, ixodidae) of chile.the tick species recorded from chile can be listed under the following headings: (1) endemic or established: argas keiransi estrada-peña, venzal and gonzalez-acuña, a. neghmei kohls and hoogstraal; ornithodoros amblus chamberlin; otobius megnini (dugès); amblyomma parvitarsum neumann; a. tigrinum koch; ixodes auritulus neumann; i. chilensis kohls; i. cornuae arthur, i. sigelos keirans, clifford and corwin; i. stilesi neumann; i. uriae white; rhipicephalus sanguineus koch. (2) probably establishe ...200515777007
susceptibility of amblyomma variegatum ticks to acaricides in ghana.abstract. the susceptibility of unfed and fed stages of larvae, nymphs and adult females of amblyomma variegatum ticks were tested using shaw's filter paper dip method against four acaricides; chlorfenvinphos and dioxathion, chlorfenvinphos, gamma benzene hexachloride and amitraz at four different concentrations including the recommended dose rates. based on their lethal concentrations (lc50 & lc90) chlorfenvinphos and dioxathion combined and chlorfenvinphos alone placed first and second, respec ...200515792105
manipulation of host cytokine network by ticks: a potential gateway for pathogen transmission.ticks are obligatory blood-feeding arthropods that secrete various immunomodulatory molecules to antagonize host inflammatory and immune responses. cytokines play an important role in regulating these responses. we investigated the extent to which ticks interact with the sophisticated cytokine network by comparing the effect of salivary gland extracts (sge) of 3 ixodid tick species, dermacentor reticulatus, amblyomma variegatum and ixodes ricinus, all of which are important vectors of tick-borne ...200515796016
observations on distribution and seasonal activity of the gulf coast tick in mississippi.medical importance of the gulf coast tick, amblyomma maculatum koch, has been highlighted with the recent discovery of a new rickettsial pathogen associated with this tick. accordingly, distribution and seasonal collection records of a. maculatum were assessed in mississippi by using three sources of data: sampling of experimental field plots, national tick collection records, and mississippi department of health human tick biting records. a. maculatum was collected in 17/82 (21%) mississippi co ...200515799527
comparison of in vitro and in vivo ectoparasiticide activity of experimental benzimidazole-carbamate with permethrin and amitraz.a series of in vitro and in vivo bioassays were conducted to assess the ectoparasiticide activity of isopropyl-4-nitro-2,6-bis(trifluoromethyl)-1-benzimidazole-carbamate, an experimental benzimidazole-carbamate class compound. this compound was less potent than permethrin against ectoparasiticide-susceptible larvae of the lone star tick, amblyomma americanum (l.) (acari: ixodidae); larvae of the southern cattle tick, boophilus microplus (canestrini); and adult stable fly, stomoxys calcitrans (l. ...200515799532
anointing chemicals and ectoparasites: effects of benzoquinones from millipedes on the lone star tick, amblyomma americanum.many mammals and birds roll on or rub themselves with millipedes that discharge benzoquinones. chemicals transferred from millipedes onto the integument of anointing animals are thought to deter ectoparasites. we tested the lone star tick, amblyomma americanum (l.), for responses to three widespread components of millipede defensive secretions, 1,4-benzoquinone; 2-methyl-1,4-benzoquinone (toluquinone); and 2-methoxy-3-methyl-1,4-benzoquinone (mmb). in toxicity tests, ticks were confined for 1 hr ...200515839480
the amblyomma maculatum koch, 1844 (acari: ixodidae: amblyomminae) tick group: diagnostic characters, description of the larva of a. parvitarsum neumann, 1901, 16s rdna sequences, distribution and hosts.a review of the largely confused amblyomma maculatum koch, 1844 tick group of the subgenus anastosiella santos dias, 1963 (a. neumanni ribaga, 1902, a. maculatum, a. parvitarsum neumann, 1901, a. tigrinum koch, 1844 and a. triste koch, 1844) is presented together with a discussion of the diagnostic characters used for the determination of adults, nymphs and, to a lesser extent, larvae. a key for this tick group is produced, including the description of the larva of a. parvitarsum, 1901. sequence ...200515841347
a cross-reactive tick cement antigen is a candidate broad-spectrum tick vaccine.truncated constructs of 64p (64trps), a secreted cement protein from salivary glands of the tick rhipicephalus appendiculatus, provided cross-protection against rhipicephalus sanguineus and ixodes ricinus, apparently by targeting antigens in the midgut and salivary glands of adults and nymphs, causing mortality. tick feeding on 64trp-immunised animals stimulated local inflammatory immune responses (involving basophils, eosinophils, lymphocytes, mast cells, macrophages and dendritic-like cells) t ...200515913855
ticks and tick-borne disease in guatemalan cattle and horses.blood samples and ticks were collected from 48 cattle and 74 horses from seven sites in the peten region of guatemala. data on body condition, mucous membrane capillary refill time and tick infestation levels were recorded for each animal in the study. horses had significantly higher levels of tick infestation than cattle, as well as poorer body condition scores. seroprevalence of babesia spp. was 95.8% for b. bovis in cattle, 89.6% for b. bigemina in cattle, and 92.7% for b. equi in horses. ser ...200515936147
systematics and evolution of ticks with a list of valid genus and species names.in recent years there has been much progress in our understanding of the phylogeny and evolution of ticks, in particular the hard ticks (ixodidae). indeed, a consensus about the phylogeny of the hard ticks has emerged which is quite different to the working hypothesis of 10 years ago. so that the classification reflects our knowledge of ticks, several changes to the nomenclature of ticks are imminent or have been made. one subfamily, the hyalomminae, should be sunk, while another, the bothriocro ...200415938503
tick-borne viruses.at least 38 viral species are transmitted by ticks. virus-tick-vertebrate host relationships are highly specific and less than 10% of all tick species (argasidae and ixodidae) are known to play a role as vectors of arboviruses. however, a few tick species transmit several (e.g. ixodes ricinus, amblyomma variegatum) or many (i. uriae) tick-borne viruses. tick-borne viruses are found in six different virus families (asfarviridae, reoviridae, rhabdoviridae, orthomyxoviridae, bunyaviridae, flaviviri ...200415938513
influence of meso- and microscale habitat structure on focal distribution of sympatric ixodes scapularis and amblyomma americanum (acari: ixodidae).we compared the distribution of sympatric ixodes scapularis say and amblyomma americanum (l.) within several suitable forested habitats at different spatial scales and characterized differences in microhabitat features accounting for the observed distribution of questing ticks. we used automatic data loggers placed in the shrub and litter layers to contrast mesoclimate and microclimate conditions experienced by questing ticks. larger numbers of i. scapularis were collected at sites where the for ...200515962776
the fc fragment mediates the uptake of immunoglobulin c from the midgut to hemolymph in the ixodid tick amblyomma americanum (acari: ixodidae).the phenomenon of immunoglobulin uptake from the midgut into the hemolymph has been observed in both argasid and ixodid ticks, but the mechanism of the uptake is not known. using capillary feeding of adult amblyomma americanum (l.) female ticks, we investigated the role of immunoglobulin g fc and fab fragments in the uptake process. intact igg and fragments labeled with 125i were introduced alone or as a mixture with a 10-fold molar excess of unlabeled compounds into ticks, and then the concentr ...200515962788
relative encounter frequencies and prevalence of selected borrelia, ehrlichia, and anaplasma infections in amblyomma americanum and ixodes scapularis (acari: ixodidae) ticks from central new jersey.to evaluate their relative importance in tick-borne disease transmission in new jersey, host-seeking amblyomma americanum (l.) and ixodes scapularis say adults and nymphs were collected during spring activity periods in 2003 and 2004 to determine relative frequencies at which these ticks were encountered from an area known to be hyperendemic for lyme disease. although similar numbers of the two species were encountered during early spring of both years, a. americanum were encountered more often ...200515962799
reptile trade and the risk of exotic tick introductions into southern south american countries.ticks exotic for the neotropical region were found on python regius imported into argentina and chile. all ticks (7 males and 3 females) were classified as amblyomma latum koch, 1844 ( = aponomma latum). additionally, four lots comprising 18 males of the argentinean tortoise tick, amblyomma argentinae neumann, 1904, were found on a terrestrial tortoise, chelonoidis chilensis, and on three terrestrial tortoises (probably c. chilensis) imported to uruguay presumably from argentina). these findings ...200515969465
redescription of amblyomma fuscum neumann, 1907 (acari: ixodidae), a rare south america tick confirmed in brazil.the species amblyomma fuscum neumann, 1907 is a rare tick found on the neotropical region, but it has not been recorded as a valid taxon in some lists proposed by current taxonomists. after a comparison between the brazilian material of a. fuscum deposited in the acari collection of the butantan institute, são paulo, brazil, and the male type deposited in leiden museum of natural history, the netherlands, we confirm the taxonomic validity of a. fuscum and redescribe the adult specimens based on ...200515980961
effects of combining the fungi beauveria bassiana and metarhizium anisopliae on the mortality of the tick amblyomma variegatum (ixodidae) in relation to seasonal changes.the effect of formulation, fungal concentration, type and seasonal changes on the mortality of the tick amblyomma variegatum was investigated. a previous study demonstrated high pathogenicity of strains of the fungi beauveria bassiana and metarhizium anisopliae against the ticks rhipicephalus appendiculatus and amblyomma variegatum (kaaya et al. j invertebr pathol 1996; 67: 15-20). the present study was undertaken to explore possible additive or synergistic effects of the two fungi on a. variega ...200515983739
sequence variation of the ribosomal dna second internal transcribed spacer region in two spatially-distinct populations of amblyomma americanum (l.) (acari: ixodidae).sequence analysis of the ribosomal dna second internal transcribed spacer (its 2) region in 2 spatially distinct populations of amblyomma americanum (l.) revealed intraspecific variation. nucleotide sequences from multiple dna extractions and several polymerase chain reaction amplifications of eggs from mixed-parentage samples from both populations of ticks revealed that 12 of 1,145 (1.0%) sites varied. three of the 12 sites of variation were distinct between the 2 a. americanum populations, whi ...200515986597
polymerase chain reaction detection of cytauxzoon felis from field-collected ticks and sequence analysis of the small subunit and internal transcribed spacer 1 region of the ribosomal rna gene.cytauxzoon felis produces a disease in domestic cats in the midwest (u.s.a.), which often leads to a fatal outcome. although the clinical disease process is well described, there are still many unanswered questions about this organism. for example, it is unknown whether species of ticks other than dermacentor variabilis can serve as vectors for transmission. with recent reports of surviving cats from limited geographic areas, another relevant question is the potential for genetically less virule ...200515986625
feeding predilection of gulf coast tick, amblyomma maculatum koch, nymphs on cattle.gulf coast tick nymphs successfully attached and fed on cattle after being freely released. six hereford heifers were each infested with approximately 2000 gulf coast tick nymphs, three with a strain originating from refugio co., tx, and three with ticks from osage co., ks by free release on the head and legs to simulate field acquisition of questing nymphs. two re-infestations were conducted, the first at 7 days and the second at 28 days. nymph dispersal was estimated by daily inspection of 22 ...200515993001
repellent efficacy of four commercial deet lotions against amblyomma hebraeum (acari: ixodidae), the principal vector of rickettsia africae in southern africa.african tick bite fever, caused by rickettsia africae, is an emerging zoonotic infection in rural sub-saharan africa and the french west indies. we tested the repellent efficacy of four commercial diethyl-3-methylbenzamide (deet) lotions against amblyomma hebraeum koch, the principal vector of r. africae in southern africa, by using a human bioassay in which repellent-treated fingers were presented to questing tick nymphs hourly for 4h. three lotions with 19.5, 31.6 and 80% deet concentrations, ...200515993907
transcription analysis of the major antigenic protein 1 multigene family of three in vitro-cultured ehrlichia ruminantium isolates.ehrlichia ruminantium, an obligate intracellular bacterium transmitted by ticks of the genus amblyomma, causes heartwater disease in ruminants. the gene coding for the major antigenic protein map1 is part of a multigene family consisting of a cluster containing 16 paralogs. in the search for differentially regulated genes between e. ruminantium grown in endothelial and tick cell lines that could be used in vaccine development and to determine if differences in the map1 gene cluster exist between ...200515995193
possible tick-borne human enterovirus resulting in aseptic meningitis.enterovirus-specific genetic sequences were isolated from two amblyomma americanum tick pools. identical genetic sequences were later obtained from cerebrospinal fluid of a patient with aseptic meningitis and a recent history of tick attachment. these observations suggest the possibility of an emerging tick-borne human enterovirus associated with aseptic meningitis.200516000481
rapid detection methods and prevalence estimation for borrelia lonestari glpq in amblyomma americanum (acari: ixodidae) pools of unequal size.dna was extracted from pools of amblyomma americanum ticks collected from vegetation at two sites in fort leonard wood, missouri and tested for the presence of borrelia spp. two new methods were developed to detect borrelia lonestari dna by targeting the glycerophosphodiester phosphodiesterase (glpq) gene. the first method detected b. lonestari dna using a sybr green i melting curve analysis of the pcr product obtained with glpq gene primers. the second method, a glpq taqman assay, detected and ...200516011431
detection of ehrlichia spp. in raccoons (procyon lotor) from georgia.raccoons (procyonis lotor) and opossums (didelphis virginianus) acquired from six contiguous counties in the piedmont physiographic region of georgia were investigated for their potential role in the epidemiology of ehrlichial and anaplasmal species. serum was tested by indirect fluorescent antibody (ifa) assay for the presence of antibodies reactive to ehrlichia chaffeensis, e. canis, and anaplasma phagocytophilum (hga agent). nested polymerase chain reaction (pcr) assay was used to test whole ...200516011433
identification of candidate sialome components expressed in ixodid tick salivary glands using secretion signal complementation in mammalian cells.ixodid ticks manipulate mammalian host pathways by secreting molecules from salivary glands. novel cdnas containing functional secretion signals were isolated from ixodid tick salivary glands using a signal sequence trap. only 15/61 rhipicephalus appendiculatus and 1/7 amblyomma variegatum cdnas had significant identity (< 1e-15) to previously identified sequences. polypeptides that may interact with host pathways included a kinase inhibitor. two proteins encoded homologues of the yolk protein v ...200516033433
rnai-mediated gene silencing to assess the role of synaptobrevin and cystatin in tick blood feeding.in addition to being the conduit for pathogens into hosts, tick saliva contains a broad array of secretory products that facilitate prolonged tick attachment and blood feeding. proteins found in tick saliva modulate host hemostasis and immune responses. however, it is not clear whether ticks manipulate the immune responses of their hosts by disrupting the antigen-processing pathways of the hosts. protein secretion into tick saliva from the salivary glands is due to exocytosis of vesicular membra ...200516040003
diagnosis of hepatozoon spp. in amblyomma ovale and its experimental transmission in domestic dogs in brazil.transmission of hepatozoon spp. to dogs was investigated using four species of ixodid ticks: rhipicephalus sanguineus, amblyomma aureolatum, amblyomma ovale and amblyomma cajennense. we collected completely or partially engorged adult ticks of these species from dogs that were naturally infested and positive for hepatozoon spp. we selected some of these ixodids and inoculated them orally in four negative dogs. the other ticks were dissected and examined for oocysts. of all dogs inoculated orally ...200516081219
ticks (acari: ixodida) on wild carnivores in brazil.the present study reports field data of ticks infesting wild carnivores captured from july 1998 to september 2004 in brazil. additional data were obtained from one tick collection and from previous published data of ticks on carnivores in brazil. during field work, a total of 3437 ticks were collected from 89 cerdocyon thous (crab-eating fox), 58 chrysocyon brachyurus (maned wolf), 30 puma concolor (puma), 26 panthera onca (jaguar), 12 procyon cancrivorus (crab-eating raccoon), 4 speothos venati ...200516082932
amblyomma latepunctatum, a valid tick species (acari: ixodidae) long misidentified with both amblyomma incisum and amblyomma scalpturatum.in 2000, we initiated an investigation on the tick fauna of rondônia state, where we collected many specimens of amblyomma scalpturatum neumann, 1906 and amblyomma incisum neumann, 1906. in addition, we also collected a third group of ticks that were morphologically closely related to those 2 species, but sufficiently different to be considered a distinct species; members of this group were subsequently identified as amblyomma latepunctatum tonelli-rondelli, 1939, through comparison with the typ ...200516108543
drop off rhythm and survival periods of amblyomma lepidum (acari: ixodidae) under field conditions.in this study, engorged amblyomma lepidum ticks were found to drop off in two peaks, one in the morning and one in the evening. most larvae and females engorged during the morning hours between 06.00 h and 10.00 h with a peak around 08.00 h, whereas the majority of the nymphs dropped in the evening between 18.00 h and 24.00 h with the peak around 22.00 h. although the effect of time on drop-off patterns of the ticks was statistically significant (p< or = 0.001), there were no significant seasona ...200516132736
a collection of ticks (ixodidae) from wild birds in uruguay.thirty nine wild birds from seven families (alcedinidae, emberizidae, furnariidae, parulidae, trochilidae, turdidae and tyrannidae) were caught from 4 to 7 of february, 2004 at rincón da vassoura (31 degrees 15' s 56 degrees 03' w) department of tacuarembó, uruguay. ninety one nymphs and forty one larvae of ixodidae were recovered from them. the majority of ticks were conventionally identified but 16s mitochondrial rdna sequences were obtained for larvae and nymphs of amblyomma with uncertain sp ...200516132744
ticks parasitizing reptiles in the bahamas.two species of reptile ticks, amblyomma dissimile koch and amblyomma torrei pérez vigueras (acari: ixodidae), are reported from the bahama islands for the first time. the widespread neotropical (including the caribbean and southern florida) a. dissimile was recovered on andros island from three species of reptiles all for the first time: the andros iguana cyclura cychlura cychlura cuvier, the andros curly tail lizard leiocephalus carinatus coryi schmidt, and the andros boa epicrates striatus fow ...200516134982
amblyomma tigrinum (acari: ixodidae): new data on hosts and biology of immature stages and on dna composition.biological data of immature stages of amblyomma tigrinum were obtained from larvae and nymphs both fed on rats and rabbits. data from nymphs recovered from a wild rodent (galea musteloides) are also reported. additional results in dna composition of males moulted from nymphs fed on laboratory and wild hosts are presented. the ticks were maintained in darkness at 27 +/- 1 degrees c and 83-86% rh. the mean recovery rates were 49.1% and 43.6% with a moulting success of 96.2% and 90.8% in larvae fed ...200516143451
description of the larva of amblyomma longirostre (koch,1844)(acari: ixodidae) by light and scanning electron microscopy.the description of the larva of amblyomma longirostre (koch, 1844) is based on optical and scanning electron microscopy. larvae (f1) were obtained under laboratory conditions from an engorged a. longirostre female, which had been collected on a coendu prehensilis (linnaeus) (rodentia: erethizontidae) from the jaraguá mountain, são paulo municipality, state of são paulo, brazil. several characters are presented including the chaetotaxy of idiosoma, palps and haller's organ, campaniform sensillum ...200516153345
[the effect of immersion in distilled water on the engorged larvae and nymphs of amblyomma cajennense (fabricius,1787)(acari: ixodidae)].to evaluate the effect of the immersion of engorged larvae and nymphs of amblyomma cajennense, these stages were immersed by 24, 48, 72 and 96 hours in test tubes containing distilled water. the period of premolt of the nymphs increased proportionally to the time of immersion (p<0.05). the ecdisis period, the longevity and the mortality (days) were similar in all of treatments (p>0.05). the percentage of ecdisis in nymphs was reduced after 72 hours of immersion of the larvae (p<0.05). none of th ...200516153347
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