TitleAbstractYear(sorted ascending)
tick paralysis of a snake caused by amblyomma rotundatum (acari: ixodidae).a lethargic southern black racer, coluber constrictor priapus dunn and wood, wild-caught in the florida keys, monroe county, fl, was found to be paralyzed by the bite of a female ixodid tick, amblyomma rotundatum koch (acari: ixodidae). removal of the tick restored the snake to normalcy within 18 h. other, earlier reported cases of tick toxicosis in reptiles are reviewed and clarified. evidently, the present incident is the only reported case of tick paralysis in a poikilotherm found in a natura ...200717294934
infection by rickettsia bellii and candidatus "rickettsia amblyommii" in amblyomma neumanni ticks from argentina.the tick species, amblyomma neumanni (acari: ixodidae) is the most frequent tick parasitizing humans in northwestern argentina. the present study evaluated the rickettsial infection among 55 a. neumanni adult free-living ticks collected in dean funes, córdoba province. ticks were individually processed by the hemolymph test with gimenez staining, isolation of rickettsia in vero cell culture by the shell vial technique, and polymerase chain reaction (pcr) targeting the citrate synthase rickettsia ...200717264991
serotonin-like immunoreactivity in the central nervous system of two ixodid tick species.immunocytochemistry was used to describe the distribution of serotonin-like immunoreactive (5ht-ir) neurons and neuronal processes in the central nervous system (cns), the synganglion, of two ixodid tick species; the winter tick, dermacentor albipictus and the lone star tick, amblyomma americanum. 5ht-ir neurons were identified in the synganglion of both tick species. d. albipictus had a significantly higher number of 5ht-ir neurons than a. americanum. the labeling pattern and number of 5ht-ir n ...200718040871
cattle ticks of the genera rhipicephalus and amblyomma of economic importance in tanzania: distribution assessed with gis based on an extensive field order to implement a robust integrated tick and tick-borne disease control programme in tanzania, based on ecological and epidemiological knowledge of ticks and their associated diseases, a national tick and sero-surveillance study was carried out in all 21 regions of the mainland, as well as on mafia island, between 1998 and 2001. the current distributions of rhipicephalus appendiculatus, r. pravus, amblyomma variegatum, a. gemma, and a. lepidum are illustrated and discussed. tick distributi ...200718044004
detection of rickettsia amblyommii in association with a tick bite the summer of 2006, an amblyomma americanum tick was removed from a woman in central north carolina, who subsequently developed a rash at the site of tick attachment. when examined by polymerase chain reaction (pcr) for borrelia, anaplasma, ehrlichia, babesia, rickettsia, and bartonella dna, only the rickettsia primers generated an amplicon, which was identified as "r. amblyommii" by sequencing. to our knowledge, this is the first case in which r. amblyommii was temporally associated with a r ...200718052716
molecular cloning of the ecdysone receptor and the retinoid x receptor from the scorpion liocheles australasiae.cdnas of the ecdysone receptor and the retinoid x receptor were cloned from the japanese scorpion liocheles australasiae, and the amino acid sequences were deduced. the full-length cdna sequences of the l. australasiae ecdysone receptor and the l. australasiae retinoid x receptor were 2881 and 1977 bp in length, respectively, and the open reading frames encoded proteins of 560 and 414 amino acids. the amino acid sequence of the l. australasiae ecdysone receptor was similar to that of the ecdyson ...200718028192
[ticks (acari: ixodidae) collected in the natural reserve of the vale do rio doce, linhares, state of espírito santo].we confirm, after decades without new registers, the occurrence of the ticks amblyomma obolongoguttatum koch, 1844, a. brasiliense aragão, 1908, and a. humerale koch, 1844 in the state of espírito santo, brazil, besides the first record of a. naponense (packard, 1869) in this state.200718078608
parasitology and urban livestock farming in nigeria: prevalence of ova in faecal and soil samples and animal ectoparasites in makurdi.domestic environmental pollution resulting from urban livestock farming was investigated in makurdi using parasitological techniques. the test tube flotation technique was used for the parasitological analysis of animal faecal matter and soil samples collected from residential premises. ectoparasitic fauna of dogs, goats, sheep and cattle cohabiting with humans within the same residential compound were also collected and identified. the hand-picking and body brushing methods were employed to sea ...200717665765
detection of "rickettsia sp. strain uilenbergi" and "rickettsia sp. strain davousti" in amblyomma tholloni ticks from elephants in date, 6 tick-borne rickettsiae pathogenic for humans are known to occur in africa and 4 of them were first identified in ticks before being recognized as human pathogens.200717683629
variegin, a novel fast and tight binding thrombin inhibitor from the tropical bont tick.tick saliva contains potent antihemostatic molecules that help ticks obtain their enormous blood meal during prolonged feeding. we isolated thrombin inhibitors present in the salivary gland extract from partially fed female amblyomma variegatum, the tropical bont tick, and characterized the most potent, variegin, one of the smallest (32 residues) thrombin inhibitors found in nature. full-length variegin and two truncated variants were chemically synthesized. despite its small size and flexible s ...200717684009
detection of rickettsia africae in rhipicephalus (boophilus) decoloratus ticks from the republic of botswana, south africa.a total of 53 engorged adult ticks belonging to the species rhipicephalus (boophilus) decoloratus (n = 9), rhipicephalus evertsi evertsi (n = 27), rhipicephalus appendiculatus (n = 9), amblyomma hebraeum (n = 5), and hyalomma marginatum turanicum (n = 3), were removed from oryx in botswana (south africa). they were tested for the presence of spotted fever group (sfg) rickettsia and anaplasma phagocytophilum using polymerase chain reaction (pcr). seventy-seven percent of r. decoloratus as well as ...200717690416
repellent efficacy of formic acid and the abdominal secretion of carpenter ants (hymenoptera: formicidae) against amblyomma ticks (acari: ixodidae).formic acid is a substance produced by some ants for defense, trail marking, and recruitment. some animals are known to rub ants or other arthropods on parts of their plumage or fur to anoint themselves with released substances. a recent study with a semifree-ranging group of capuchin monkeys, cebus apella l., in the tietê ecological park, sao paulo, brazil, an area of occurrence of the tick species amblyomma cajennense (f.), revealed that "anting" with carpenter ants, camponotus rufipes f. (hym ...200717695031
transmission of ehrlichia chaffeensis from lone star ticks (amblyomma americanum) to white-tailed deer (odocoileus virginianus).amblyomma americanum is an aggressive ixodid tick that has been implicated as a vector for several bacterial agents. among these is ehrlichia chaffeensis, which causes human monocytic (or monocytotropic) ehrlichiosis. in this study, experimental tick transmission of e. chaffeensis from infected lone star ticks to deer was revisited, and the question of whether it would be possible to re-isolate the organism from deer was asked, because this had not been done previously. here, we were able to tra ...200717699076
[parasitism by amblyomma triste in domestic cat].amblyomma triste is an ixodidae, ectoparasite of several mammals' species, with occurrence reported in argentina, brazil, colombia, ecuador, peru, uruguay and venezuela. the aim of this work was to register the parasitism by a. triste in domestic cat (felis catus) in rio grande do sul state, brazil.200717706014
goats as alternative hosts of cattle ticks.the objective of this study was to compare the presence on goats and cattle of adult ticks that usually infest cattle. to this end ticks collected from sets of five goats were compared with those collected from sets of five cattle at 72 communal dip-tanks in the eastern region of the eastern cape province. amblyomma hebraeum was present on goats at 25 and on cattle at 39 dip-tanks, and a total of 61 goats and 138 cattle were infested. adult rhipicephalus (boophilus) microplus was present on goat ...200717708147
localization and visualization of a coxiella-type symbiont within the lone star tick, amblyomma americanum.a coxiella-type microbe occurs at 100% frequency in all amblyomma americanum ticks thus far tested. using laboratory-reared ticks free of other microbes, we identified the amblyomma-associated coxiella microbe in several types of tissue and at various stages of the life cycle of a. americanum by 16s rrna gene sequencing and diagnostic pcr. we visualized amblyomma-associated coxiella through the use of a diagnostic fluorescence in situ hybridization (fish) assay supplemented with pcr-based detect ...200717720830
molecular and expression analysis of a family of the amblyomma americanum tick lospins.serine proteinase inhibitors (serpins) are a family of structurally similar but functionally diverse proteins that regulate several important proteolytic cascades in most branches of life. we have characterized 17 amblyomma americanum serpin cdnas here named as ;lospins' (l; an acronym for lone star tick serpin) that possess three beta-sheets, eight alpha-helices and a reactive center loop consistent with the consensus serpin superfamily secondary structures. visual inspection of deduced amino a ...200717766296
detection of a novel spotted fever group rickettsia in amblyomma parvum ticks (acari: ixodidae) from argentina.the present study evaluated the rickettsial infection in amblyomma parvum ticks collected in northwestern córdoba province, argentina. each tick was subjected to dna extraction and tested by polymerase chain reaction (pcr) targeting fragments of the rickettsial genes glta and ompb. nine (69.2%) out of 13 adult ticks yielded expected pcr products for the two rickettsial genes. products from the ompb pcr were sequenced, generating dna sequences 100% identical for the nine pcr-positive ticks. three ...200717768597
geographical distribution of ticks in turkey.turkey's tick fauna is composed of about 32 species in two families and ten genera in mammals, reptiles, and birds. the ticks of veterinary significance in the family ixodidae comprise seven genera with 28 different species. ixodes spp. are mostly seen in northern turkey. it is likely that the high rainfall and the intensive forest in this area may contribute to this observation. to date, the following species have been found to be sporadically present: amblyomma variegatum in hatay province (bo ...200717823820
tick fauna from two locations in the brazilian savannah.the cerrado is brazil's tropical savannah, which is arguably under greater threat than the amazon rainforest. the cerrado biome of tropical south america covers about 2 million km(2) and is considered a biodiversity hot spot which means that it is especially rich in endemic species and particularly threatened by human activities. the cerrado is increasingly exposed to agricultural activities which enhance the likelihood of mixing parasites from rural, urban and wildlife areas. information about ...200717828441
ecological havoc, the rise of white-tailed deer, and the emergence of amblyomma americanum-associated zoonoses in the united states.two infectious diseases, and one presumably infectious disease, each vectored by or associated with the bite of the lone star tick (amblyomma americanum), were identified and characterized by clinicians and scientists in the united states during the 1980s and 1990s. these three conditions-human monocytic (or monocytotropic) ehrlichiosis (hme), ehrlichia ewingii ehrlichiosis, and southern tick-associated rash illness (stari)-undoubtedly existed in the united states prior to this time. however, th ...200717848069
ticks collected on birds in the state of são paulo, brazil.the present study reports a collection of amblyomma spp. ticks in birds from several areas of the state of são paulo, brazil. a total of 568 tick specimens (404 larvae, 164 nymphs) were collected from 261 bird specimens. from these ticks, 204 (36%) specimens (94 larvae, 110 nymphs) were reared to the adult stage, being identified as amblyomma longirostre (94 larvae, 90 nymphs), amblyomma calcaratum (13 nymphs), amblyomma nodosum (2 nymphs), and amblyomma cajennense (5 nymphs). additionally, 39 l ...200717882514
life cycles of seven ixodid tick species (acari: ixodidae) under standardized laboratory conditions.studies of transmission, maintenance, infectivity, virulence, and pathogenicity of tick-borne agents require the use of large numbers of live laboratory-raised ticks. colonies of ixodes scapularis say, ixodes pacificus cooley & kohls, amblyomma americanum (l.), dermacentor occidentalis marx, dermacentor variabilis (say), hemaphysalis leporispalustris (packard), and rhipicephalus sanguineus (latrielle) have been maintained in our laboratory at the centers for disease control and prevention for fi ...200717915502
immunisation of sheep against heartwater in the gambia using inactivated and attenuated ehrlichia ruminantium vaccines.heartwater (cowdriosis) is a disease of ruminants caused by a rickettsial pathogen ehrlichia ruminantium and transmitted by ticks of the genus amblyomma. the purpose of this work was to evaluate the protective efficacies of inactivated and attenuated vaccines to protect sheep against heartwater in the gambia. an inactivated vaccine, prepared from e. ruminantium (gardel stock), and a live attenuated vaccine from e. ruminantium (senegal stock), were evaluated in two independent on-station trials. ...200717920167
confirmation of the efficacy of a novel formulation of metaflumizone plus amitraz for the treatment and control of fleas and ticks on dogs.a novel spot-on formulation containing metaflumizone plus amitraz (promeris/promeris duo for dogs, fort dodge animal health, overland park, ks) was evaluated in four laboratory studies to confirm efficacy against fleas and ticks on dogs for 1 month. three different strains of cat flea (ctenocephalides felis felis) and four tick species were used. rhipicephalus sanguineus and dermacentor variabilis were evaluated concurrently in two studies and ixodes scapularis and amblyomma americanum in one st ...200717923330
ticks associated with the three largest wild ruminant species in southern africa.the objective of this study was to assess the host status of the three largest southern african wild ruminants, namely giraffes, giraffa camelopardalis, african buffaloes, syncerus caffer, and eland, taurotragus oryx for ixodid ticks. to this end recently acquired unpublished data are added here to already published findings on the tick burdens of these animals, and the total numbers and species of ticks recorded on 12 giraffes, 18 buffaloes and 36 eland are summarized and discussed. twenty-eigh ...200717933365
a hard tick relapsing fever group spirochete in a brazilian rhipicephalus (boophilus) microplus.tick-borne diseases usually comprise a complex epidemiological and ecological network connecting the vector, pathogen, and a group of host species. symptoms associated with lyme disease have been reported in brazil, but no borrelia sp. has been definitively related to these events. here we have identified a b. lonestari/b. theileri-related spirochete dna in the cattle tick rhipicephalus (boophilus) microplus from brazil. four hundred r. microplus and 80 amblyomma cajennense ticks were screened, ...200717979536
ticks and associated pathogens collected from domestic animals in the netherlands.following an outbreak of autochthonous canine babesiosis in the netherlands, a request made to veterinarians and the public to collect ticks from companion animals resulted in 4298 ticks submitted between july 2005 and october 2006 to our center. ticks were identified as ixodes ricinus adults (2907/4298, 67.6%), ixodes sp. nymphs (529/4298, 12.3%) and ixodes sp. larvae (385/4298, 9.0%), i. hexagonus adults (328/4298, 7.6%), dermacentor reticulatus (72/4298, 1.7%), and several other exotic tick s ...200717979540
natural and experimental infection of the lizard ameiva ameiva with hemolivia stellata (adeleina: haemogregarinidae) of the toad bufo marinus.developmental stages of a haemogregarine in erythrocytes of the lizard ameiva ameiva (teiidae), from pará state, north brazil, were shown to be those of hemolivia by the nature of the parasite's sporogonic cycle in the tick amblyomma rotondatum. the type species, hemolivia stellata petit et al., 1990 was described in the giant toad bufo marinus and the tick amblyomma rotondatum, also from pará state, and in view of the fact that a. ameiva and bufo marinus share the same habitat and are both comm ...200718225421
hyperparasitism in amblyomma rotundatum (acari: ixodidae).in the present study, we report a case of hyperparasitism in amblyomma rotundatum. during examination of live ticks immediately after collecting them from boa constrictor snakes held in a reptile facility in mossoró, rn, northeastern brazil, 1 unengorged tick female was seen attached to the venter of a partially engorged female. the hypostome and chelicerae of the unengorged female had penetrated the integument of the partially engorged female to the level of the basis capitulli and the palps we ...200718314708
rickettsial infection in capybaras (hydrochoerus hydrochaeris) from são paulo, brazil: serological evidence for infection by rickettsia bellii and rickettsia brazil, capybaras (hydrochoerus hydrochaeris) are important hosts for amblyomma ticks, which in turn can transmit rickettsiae to humans and animals. therefore, capybaras are potential sentinels for rickettsial infection.200718320102
rickettsia parkeri in brazil.we report finding rickettsia parkeri in brazil in 9.7% of amblyomma triste ticks examined. an r. parkeri isolate was successfully established in vero cell culture. molecular characterization of the agent was performed by dna sequencing of portions of the rickettsial genes glta, htra, ompa, and ompb.200718214195
distribution and population dynamics of ticks (acari: ixodidae) infesting sheep in sennar state, sudan.a cross-sectional survey of ticks infesting sheep was conducted in sennar state, sudan. a total body collection of ticks was carried out at five localities sennar town, singa, dinder, abu naama and um banein on two types of desert sheep (watish and ashgar) on two farms at each locality at two monthly intervals for one year starting july 2002 to may 2003. four tick genera and eight species were identified. they were amblyomma lepidum, hyalomma anatolicum anatolicum, hyalomma truncatum, rhipicepha ...200718453239
[effect of the strategic control of amblyomma cajennense (fabricius, 1787) (acari: ixodidae) on the population of anocentor nitens (neumann, 1897) (acari: ixodidae) in equines].the objective of this study was to evaluate the effect of the amblyomma cajennense strategic control program on the anocentor nitens population. the acaricide treatments were carried out every seven days and divided in two series, the first one beginning in april 2004 (eight treatments) and the second beginning in july of the same year (five treatments), using pyrethroid chemical base - cypermethrin in the concentration of 0,015%. monthly it was evaluated the infestation of a. nitens in the ear ...200718373898
[strategic control of amblyomma cajennense (fabricius, 1787) (acari: ixodidae) on horses, minas gerais, brazil - part i].the aim of this study was to verify the efficiency of a strategic control program of amblyomma cajennense in horses under field conditions. acaricide treatments were applied at seven days intervals and divided in two series, the first one beginning in april 2004 (eight treatments), and the second one beginning in july 2004 (five treatments), aiming to control larvae and nymphs of the tick. a pyrethroid chemical base cypermethrin 0.015% was used for spraying the horses. there was a reduction of 4 ...200718373899
[the first report of amblyomma fuscum neumann, 1907 (acari ixodidae) on the lizard tupinambis teguixin (l.) at the municipality of glorinha, state of rio grande do sul, brazil].amblyomma fuscum known only from brazil has been described as a rare tick species with few reports of its occurrence in south and southeast region. this is a new records this tick species (9 females) parasitizing lizard (tupinambis teguixin) at the municipality of glorinha, state of rio grande do sul. the females were deposited in the tick collection of veterinary research institute desiderio finamor (7 specimens), eldorado do sul, rs and in the acari collection from instituto butantan, são paul ...200718373904
species diversity and seasonality of free-living ticks (acari: ixodidae) in the natural habitat of wild marsh deer (blastocerus dichotomus) in southeastern brazil.this study evaluated the presence and seasonal activity of free-living ticks in remaining marsh areas by the paraná river, in brazil. eight field trips (once per season) for collection of ticks were performed during 2 years. using co2 traps, dragging, and visual inspection of vegetation, five free-living tick species were collected, in the following order of abundance: amblyomma cajennense, amblyomma dubitatum, amblyomma triste, amblyomma coelebs, and amblyomma nodosum. the seasonal pattern of a ...200716962241
a preliminary investigation of ehrlichia species in ticks, humans, dogs, and capybaras from brazil.a molecular epidemiologic investigation in two brazilian states (rondônia and são paulo) was undertaken to determine if ehrlichia species responsible for human and animal ehrlichioses in north america could be found in brazilian vectors, potential natural mammalian reservoirs and febrile human patients with a tick bite history. samples, including 376 ticks comprising 9 amblyomma species, 29 capybara (hydrochaeris hydrochaeris) spleens, 5 canine blood, and 75 human blood samples from febrile pati ...200716962245
highly prevalent coxiella sp. bacterium in the tick vector amblyomma americanum.laboratory-reared and field-collected amblyomma americanum ticks were hosts of a coxiella sp. and a rickettsia sp. while the coxiella sp. was detected in 50 of 50 field-collected ticks, the rickettsia sp. was absent from 32% of ticks. the coxiella sp. showed evidence of a reduced genome and may be an obligate endosymbiont.200717085709
sero-prevalence and risk indicators for canine ehrlichiosis in three rural areas of brazil.ehrlichia canis has a worldwide geographic distribution, occurring particularly in tropical and subtropical areas. in brazil, the main vector in urban areas is believed to be the brown dog tick rhipicephalus sanguineus, but little is known about the occurrence, transmission and other epidemiological aspects of canine ehrlichiosis in rural areas, where amblyomma ticks are found more frequently than r. sanguineus. a sero-prevalence study of canine ehrlichiosis was carried out in three distinct rur ...200717204439
association of the bovine leukocyte antigen major histocompatibility complex class ii drb3*4401 allele with host resistance to the lone star tick, amblyomma americanum.the mhc of cattle, known as the bovine leukocyte antigen (bola) complex, plays an integral role in disease and parasite susceptibility, and immune responsiveness of the host. while susceptibility to tick infestation in cattle is believed to be heritable, genes that may be responsible for the manifestation of this phenotype remain elusive. in an effort to analyze the role that genes within the bola complex may play in host resistance to ticks, we have evaluated components of this system within a ...200717208379
infection of ixodes scapularis ticks with rickettsia monacensis expressing green fluorescent protein: a model system.ticks (acari: ixodidae) are ubiquitous hosts of rickettsiae (rickettsiaceae: rickettsia), obligate intracellular bacteria that occur as a continuum from nonpathogenic arthropod endosymbionts to virulent pathogens of both arthropod vectors and vertebrates. visualization of rickettsiae in hosts has traditionally been limited to techniques utilizing fixed tissues. we report epifluorescence microscopy observations of unfixed tick tissues infected with a spotted fever group endosymbiont, rickettsia m ...200717125789
vitellogenesis in the tick amblyomma triste (koch, 1844) (acari: ixodidae) role for pedicel cells.this study presents new information on the vitellogenesis of the tick amblyomma triste. in this species, the ovary consists of a layer of epithelial cells, which form the ovarian wall, oogonia and developing oocytes; and the pedicel, a cellular structure that synthesizes and provides yolk precursors for developing oocytes. the pedicel also attaches oocytes to the external surface of the epithelial wall. in this study, evidence is provided in support of pedicel cells in providing compounds for oo ...200716978785
haemaphysalis longicornis: molecular characterization of a homologue of the macrophage migration inhibitory factor from the partially fed ticks.the macrophage migration inhibitory factor (mif) has been identified from some vertebrates and invertebrates. mif is related to inflammation, tumor growth, and angiogenesis in vertebrates. here, we report the molecular characterization of a homologue of mif from partially fed haemaphysalis longicornis. the sequence analysis of the h. longicornis mif (hlmif) indicated that its deduced amino acid sequence has an identity of 77% with the mif of the tick amblyomma americanum. western blot analysis u ...200716987517
fecal nirs: detection of tick infestations in cattle and horses.anti-tick treatments are often applied concurrent to routine livestock management practices with little regard to actual infestation levels. prescription treatments against ticks on grazing cattle would be facilitated by non-invasive detection methods. one such method is fecal near infrared spectroscopy (nirs). four studies utilizing cattle (bos spp.) and one with horses (equus caballus) fed varying diets and infested with either amblyomma americanum, a. maculatum, a. cajennense or dermacentor a ...200717097809
using invaded range data to model the climate suitability for amblyomma variegatum (acari: ixodidae) in the new world.climate matching models are in increasing use to predict distributions of living organisms, using records of the known distribution of a species to map its expected range of habitat suitability. here, we modelled the known distribution of the tick amblyomma variegatum in africa as a preliminary step to delineate the most probable range of climatically suitable habitat for the tick in the new world. we used two presence-only methods (one based in the gower distance, the other based on the maximum ...200717347921
the ticks (acari: ixodida: argasidae, ixodidae) of paraguay.the ticks reported in paraguay, which are here reviewed, can be categorized as 'endemic or established' (argas persicus or a sibling species, ornithodoros hasei, o. rostratus, o. rudis, o. talaje/o. puertoricensis, amblyomma aureolatum, am. auricularium, am. brasiliense, am. cajennense, am. calcaratum, am. coelebs, am. dissimile, am. dubitatum, am. incisum, am. longirostre, am. nodosum, am. ovale, am. pacae, am. parvum, am. pseudoconcolor, am. rotundatum, am. scutatum, am. tigrinum, am. triste, ...200717362600
differential anti-chemokine activity of amblyomma variegatum adult ticks during blood-feeding.ticks secrete a cocktail of immunomodulatory molecules in their saliva during blood-feeding, including chemokine-binding factors that help control the activity of host immunocompetent cells. here we demonstrate differential dynamics of anti il-8 (cxcl8), mcp-1 (ccl2), mip-1 (ccl3), rantes (ccl5) and eotaxin (ccl11) activities in salivary gland extracts of adult amblyomma variegatum. unfed male and female ticks showed activity against all the chemokines except ccl5; anti-ccl11 activity was partic ...200717371454
transovarial silencing of the subolesin gene in three-host ixodid tick species after injection of replete females with subolesin dsrna.rna interference (rnai) has become the most powerful experimental tool for the study of gene function in ticks. subolesin, initially called 4d8, was found to be protective against tick infestations when used as a vaccine and was shown to be highly conserved among ixodid tick species at the nucleotide and protein levels. rnai caused systemic silencing of subolesin and demonstrated that this protein is involved in regulation of tick feeding, reproduction, and development. recently, these results w ...200717372765
repellency of two terpenoid compounds isolated from callicarpa americana (lamiaceae) against ixodes scapularis and amblyomma americanum ticks.callicarpenal (13, 14, 15, 16-tetranor-3-cleroden-12-al) and intermedeol [(4s,5s,7r,10s)-eudesm-11-en-4-ol], isolated from american beautyberry, callicarpa americana (lamiaceae), were evaluated in laboratory bioassays for repellent activity against host-seeking nymphs of the blacklegged tick, ixodes scapularis, and lone star tick, amblyomma americanum. a strip of organdy cloth treated with test solution was doubly wrapped (treatment on outer layer) around the middle phalanx of a forefinger and t ...200717380408
description of lyme disease-like syndrome in brazil. is it a new tick borne disease or lyme disease variation?an emerging clinical entity that reproduces clinical manifestations similar to those observed in lyme disease (ld) has been recently under discussion in brazil. due to etiological and laboratory particularities it is named ld-like syndrome or ld imitator syndrome. the condition is considered to be a zoonosis transmitted by ticks of the genus amblyomma, possibly caused by interaction of multiple fastidious microorganisms originating a protean clinical picture, including neurological, osteoarticul ...200717401487
the molecular basis of the amblyomma americanum tick attachment phase.towards discovery of molecular signaling cascades that trigger and/or facilitate the tick attachment and formation of its feeding lesion, suppressive subtractive hybridization, high throughput sequencing and validation of differential expression by cdna dot blot hybridization were performed on amblyomma americanum ticks that had attained appetence and were exposed to feeding stimuli. this approach allowed for identification of 40 genes that are up regulated before ticks begin to penetrate the ho ...200717406795
topographical and numerical study of the idiosomal integumentary structures of the larva of four neotropical species of amblyomma koch, 1844 (acari: ixodidae).integumentary structures of the larvae of amblyomma longirostre (koch, 1844), a. parvum aragão, 1908, a. rotundatum koch, 1844 and from three populations of a. cajennense (fabricius, 1787) were studied using light microscopy. a new nomenclature for the localisation of the integumentary structures is proposed. three types of integumentary structures were identified in the larval idiosoma of the four amblyomma species: lyrifissures, small glands and large wax glands. these structures were observed ...200717417718
poor inheritance of low attractiveness for amblyomma variegatum in cattle.because of the high variability of cattle infestation, selective breeding has been proposed to control three-host ticks in africa in the same way as it has been implemented to control the one-host tick boophilus microplus in australia. interbreeding (divergent selection experiment) between gudali zebu cattle was performed at the wakwa research centre, adamawa, cameroon to assess the feasibility and impact of such a selective breeding programme. fifty cows (chosen out of 129) and 2 bulls (chosen ...200717418491
taxonomic and phylogenetic relationships between neotropical species of ticks from genus amblyomma (acari: ixodidae) inferred from second internal transcribed spacer sequences of rdna.the accurate specific identification of ticks is essential for the study, control and prevention of tick-borne diseases. herein, we determined ribosomal nucleotide sequences of the second internal transcribed spacer (its2) of 15 neotropical hard tick species of the genus amblyomma koch found in brazil. most of the studied ticks accidentally parasite humans and potentially act as vectors of zoonoses. lengths of the its2 sequences ranged from 956 to 1,207 bp, whereas gc content varied from 62.4 to ...200717427690
amblyomma triste (koch, 1844) (acari: ixodidae) ovaries: an ultrastructural analysis.this study presents an ultrastructural analysis of the ovary of the tick, amblyomma triste. the ovary of this species is of the panoistic type that is, without nursing and follicular cells. it is composed of a layer of epithelial cells forming a wall and of germinative cells that generate the oocytes which remain attached to the external margin of this wall by a multicellular pedicel. the different developmental stages in the oocytes had been described by oliveira et al. [oliveira, p.r., bechara ...200717433302
validation and redescription of amblyomma romitii tonelli-rondelli, 1939 (acari: ixodidae).the current synonymy of amblyomma romitii tonelli-rondelli, 1939, a neotropical species, with the oriental species a. extraoculatum neumann, 1899 is discussed. the type-specimens of both species were examined and their morphological differences determined. considering their morphology and their different continental origins, we are reasonably certain that both taxa are valid. the type-specimen of a. extraoculatum is a female labelled as being from singapore. this is the only locality data on thi ...200717464485
antibiotic treatment of the tick vector amblyomma americanum reduced reproductive fitness.the lone star tick amblyomma americanum is a common pest and vector of infectious diseases for humans and other mammals in the southern and eastern united states. a coxiella sp. bacterial endosymbiont was highly prevalent in both laboratory-reared and field-collected a. americanum. the coxiella sp. was demonstrated in all stages of tick and in greatest densities in nymphs and adult females, while a rickettsia sp. was less prevalent and in lower densities when present.200717476327
molecular detection of ehrlichia ruminantium infection in amblyomma variegatum ticks in the west africa, losses due to heartwater disease are not known because the incidence/prevalence has not been well studied or documented. to develop a diagnostic tool for molecular epidemiology, three pcr-based diagnostic assays, a nested pcs20 pcr, a nested map1 pcr and a nested reverse line blot (rlb) hybridization assay, were evaluated to determine their ability to detect infection in vector ticks, by applying them simultaneously to a. variegatum field ticks to detect ehrlichia ruminantium, th ...200717476576
ultrastructural detection of proteins, lipids and carbohydrates in oocytes of amblyomma triste (koch, 1844) (acari; ixodidae) during the vitellogenesis process.the ovary of the tick amblyomma triste is classified as panoistic, which is characterized by the presence of oogonia without nurse and follicular cells. the present study has demonstrated that the oocytes in all developmental stages (i-iv) are attached to the ovary through a pedicel, a cellular structure that synthesizes and provides carbohydrate, lipids and proteins supplies for the oocytes during the vitellogenesis process. the lipids are deposited during all oocyte stages; they are freely dis ...200717544471
a call for renewed research on tick-borne francisella tularensis in the arkansas-missouri primary national focus of tularemia in humans.arkansas-missouri has emerged as the primary u.s. focus of tularemia, which is caused by the national institute of allergy and infectious diseases category a priority pathogen francisella tularensis, over the past 30 yr. there are several pieces of indirect evidence suggesting that a key role of ticks in the transmission of f. tularensis to humans in arkansas-missouri is the primary reason why tularemia has remained a prominent disease of humans in this two-state area while fading away from othe ...200717547223
transmission of bacterial agents from lone star ticks to white-tailed deer.amblyomma americanum (l.), the lone star tick, is an aggressive ixodid tick that has been implicated as a vector for several bacteria. among these bacteria are the disease agents ehrlichia chaffeensis and ehrlichia ewingii, and the putative disease agent "borrelia lonestari." the hypothesis in this study was that wild lone star ticks from northeastern georgia are capable of transmitting all three agents to white-tailed deer, odocoileus virginianus, a known reservoir host for e. chaffeensis. in t ...200717547234
tissue and life-stage distribution of a defensin gene in the lone star tick, amblyomma americanum.the transcript sequence of the amblyomma americanum linnaeus (acari: ixodidae) defensin, termed amercin (amn), was ascertained and a 219-bp amn coding region identified. the gene encodes a 72-amino acid prepropeptide with a putative 37-amino acid mature peptide. this gene shows little similarity to either of the defensins from amblyomma hebraeum koch, the only other amblyomma species for which a defensin has been described. sequence comparisons with other tick defensins reveal amn to be shorter ...200717550433
gulf coast ticks (amblyomma maculatum) and rickettsia parkeri, united states.geographic distribution of rickettsia parkeri in its us tick vector, amblyomma maculatum, was evaluated by pcr. r. parkeri was detected in ticks from florida, georgia, kentucky, mississippi, oklahoma, and south carolina, which suggests that a. maculatum may be responsible for additional cases of r. parkeri rickettsiosis throughout much of its us range.200717553257
seasonal density fluctuations of the exotic ornate kangaroo tick, amblyomma triguttatum triguttatum koch, and its distribution on yorke peninsula, south australia.the ornate kangaroo tick, amblyomma triguttatum triguttatum, was recently recorded on southern yorke peninsula, south australia. we examined seasonal fluctuations in a. triguttatum triguttatum life stages (adult, larva, and nymph) and its distribution on the peninsula. we used in situ co2 traps and dragging cloths to determine monthly fluctuations in free-living ticks at four sites at innes national park from january to december 2006, and to determine the tick's distribution on wider yorke penin ...200717587053
[efficiency of beauveria bassiana and metarhizium anisopliae formulations on amblyomma cajennense (fabricius, 1787) nymphae].amblyomma cajennense is a vector of several infectious diseases on mammals and became a serious problem in some localities in brazil. entomopathogenic fungi are very important biocontrol agents and could be a viable alternative for the control of this tick in permanent preserved areas. the aim of this study was to evaluated the mortality of tick nymphae treated with beauveria bassiana and metarhizium anisopliae formulations in laboratory conditions. non fed nymphae were inoculated with 2x10(7) a ...200717588319
hosts of the exotic ornate kangaroo tick, amblyomma triguttatum triguttatum koch, on southern yorke peninsula, south australia.amblyomma triguttatum triguttatum is assumed to be endemic to south-western western australia (including barrow island), queensland (excluding cape york peninsula), and new south wales, south to dubbo and barham. the species has been recorded on a range of mammalian hosts including macropods and domestic animals. in queensland, a. triguttatum triguttatum is implicated in the epidemiology of q fever. in 2000, the species was detected on southern yorke peninsula in south australia. we aimed to ide ...200717611781
ixodes philipi (acari: ixodidae): phylogenetic status inferred from mitochondrial cytochrome oxidase subunit i gene sequence comparison.ixodes philipi ticks were collected from the nest burrows of streaked shearwaters, calonectris luecomelas, on 3 different islands of japan (awashima: 38 degrees 45'n, 139 degrees 24'e; mikurajima: 33 degrees 52'n, 139 degrees 36'e; and omorijima: 36 degrees 8'n, 133 degrees 10'e). the mitochondrial cytochrome oxidase subunit i (coi) gene sequence was determined for each tick. the coi sequences of 9 other ixodid tick species also were determined, and they were used for taxonomic positioning of i. ...200717626375
seasonal activity of amblyomma spp. in mississippi. 200717633438
genetic diversity of ehrlichia ruminantium in amblyomma variegatum ticks and small ruminants in the gambia determined by restriction fragment profile analysis.understanding genetic diversity of ehrlichia ruminantium in host and vector populations is an important prerequisite to controlling heartwater by vaccination in traditional livestock systems in sub-saharan africa. we carried out a study in two phases: (i) evaluating the usefulness of the pcr-rflp assay based on the map1 coding sequence of e. ruminantium as a discriminatory tool to characterise genetic diversity, (ii) applying the technique to field samples from amblyomma variegatum ticks and sma ...200817646061
rocky mountain spotted fever in argentina.we describe the first molecular confirmation of rickettsia rickettsii, the cause of rocky mountain spotted fever (rmsf), from a tick vector, amblyomma cajennense, and from a cluster of fatal spotted fever cases in argentina. questing a. cajennense ticks were collected at or near sites of presumed or confirmed cases of spotted fever rickettsiosis in jujuy province and evaluated by polymerase chain reaction assays for spotted fever group rickettsiae. dna of r. rickettsii was amplified from a pool ...200818385370
a novel sine family occurs frequently in both genomic dna and transcribed sequences in ixodid ticks of the arthropod sub-phylum chelicerata.reassociation kinetics and flow cytometry data indicate that ixodid tick genomes are large, relative to most arthropods, containing>or=10(9) base pairs. the molecular basis for this is unknown. we have identified a novel small interspersed element with features of a trna-derived sine, designated ruka, in genomic sequences of rhipicephalus appendiculatus and boophilus (rhipicephalus) microplus ticks. the sine was also identified in expressed sequence tag (est) databases derived from several tissu ...200818394826
characterization of rickettsial infection in amblyomma americanum (acari: ixodidae) by quantitative real-time polymerase chain reaction.several species of the spotted fever group rickettsia (sfgr), with considerable variation in vertebrate host pathogenicity, are present in ticks in the united states. in this study, quantitative real-time pcr (qpcr) was used to characterize the growth and the distribution of rickettsia amblyommii in selected tissues (salivary glands, gut, and ovaries) of naturally infected amblyomma americanum (l.) (acari: ixodidae), during bloodmeal acquisition and throughout vertical transmission to eggs and p ...200818402143
amblyomma variegatum in cattle in marie galante, french antilles: prevalence, control measures, and infection by ehrlichia ruminantium.we report marie galante as one of the caribbean islands most heavily infested by the tropical bont tick (tbt) amblyomma variegatum which is associated with two major diseases of ruminants: heartwater and dermatophilosis. in 2005, a survey was undertaken to assess the prevalence of tbt infestation in cattle, the prevalence of ehrlichia ruminantium infection in tbts, and the tick control measures implemented by livestock owners. a random sample of 195 cattle herds out of 1885 recorded on the islan ...200818406061
molecular identification of rickettsia felis in ticks and fleas from an endemic area for brazilian spotted fever.rickettsioses are arthropod-borne diseases caused by parasites from the order rickettsiales. the most prevalent rickettsial disease in brazil is brazilian spotted fever (bsf). this work intends the molecular detection of those agents in ectoparasites from an endemic area of bsf in the state of espírito santo. a total of 502 ectoparasites, among them amblyomma cajennense, amblyomma dubitatum (a. cooperi), riphicephalus sanguineus, anocentor nitens and ctenocephalides felis, was collected from dom ...200818425272
human perception and awareness of ticks in a south australian rural community and implications for management of amblyomma triguttatum triguttatum.the ornate kangaroo tick, amblyomma triguttatum triguttatum, is invasive on yorke peninsula, south australia. to assess the potential for developing comprehensive management strategies for the species, we mailed 1,000 surveys to yorke peninsula residents to investigate community perceptions of ticks, gather information on tick-host ecology, and assess whether or not occupation and length of residence affected whether residents had seen ticks. the response rate was 32%; most respondents (63%) had ...200818427936
the tick fauna of sulawesi, indonesia (acari: ixodoidea: argasidae and ixodidae).twenty-six species of ticks are reported from the island of sulawesi (celebes), indonesia. these include two species of soft ticks (argasidae), carios batuensis and c. vespertilionis, and the following 24 species of hard ticks (ixodidae): amblyomma babirussae, a. breviscutatum, a. cordiferum, a. fimbriatum, a. helvolum, a. testudinarium, a. trimaculatum, a. varanense, dermacentor atrosignatus, d. steini, haemaphysalis celebensis, h. hystricis, h. kadarsani, h. papuana, h. psalistos, h. renschi, ...200818427937
experimental and field studies on the suitability of raccoons (procyon lotor) as hosts for tick-borne pathogens.we investigated the experimental susceptibility and natural exposure of raccoons (procyon lotor) to five tick-borne pathogens of human and veterinary importance, ehrlichia canis, e. chaffeensis, e. ewingii, anaplasma phagocytophilum (apvariant 1 and ap-ha hge-1 strains), and borrelia lonestari. infections were assessed by polymerase chain reaction (pcr), indirect fluorescent antibody (ifa) testing, and/or culture isolation methods for at least 30 days postinoculation (dpi). two e. chaffeensis-in ...200818429696
geographic distribution and genetic diversity of the ehrlichia sp. from panola mountain in amblyomma americanum.a novel ehrlichia, closely related to ehrlichia ruminantium, was recently discovered from panola mountain state park, ga, usa. we conducted a study to determine if this agent was recently introduced into the united states.200818433500
natural and experimental infection of white-tailed deer (odocoileus virginianus) from the united states with an ehrlichia sp. closely related to ehrlichia ehrlichia sp. (panola mountain [pm] ehrlichia sp.) closely related to ehrlichia ruminantium was recently detected in a domestic goat experimentally infested with lone star ticks (lsts, amblyomma americanum) collected from georgia, usa. the infected goat exhibited pyrexia and mild clinical pathologic abnormalities consistent with ehrlichiosis. at least two other ehrlichia species (ehrlichia chaffeensis and ehrlichia ewingii) are maintained in nature by a cycle involving lsts as the primary vec ...200818436670
molecular detection of spotted fever group rickettsiae in ticks from ethiopia and chad.dna extracted from 363 ticks collected in ethiopia and 9 ticks collected in chad, africa were screened by pcr to detect dna from spotted fever group rickettsiae. fifteen ticks (4.1%) collected in ethiopia and one tick (11%) collected in chad tested positive when pcr targeting the glta and ompa rickettsial genes was performed. pcr-positive products of the glta and ompa genes were used for dna sequencing. rickettsia africae was detected in 12/118 amblyomma lepidum and in 1/2 a. variegatum. also, 2 ...200818440576
tick-borne diseases in north carolina: is "rickettsia amblyommii" a possible cause of rickettsiosis reported as rocky mountain spotted fever?cases of rocky mountain spotted fever (rmsf) in north carolina have escalated markedly since 2000. in 2005, we identified a county in the piedmont region with high case numbers of rmsf. we collected ticks and examined them for bacterial pathogens using molecular methods to determine if a novel tick vector or spotted fever group rickettsiae (sfgr) might be emerging. amblyomma americanum, the lone star tick, comprised 99.6% of 6,502 specimens collected in suburban landscapes. in contrast, dermacen ...200818447622
stari, or masters disease: lone star tick-vectored lyme-like illness.lyme-like illness (also known as southern tick-associated rash illness [stari] or masters disease) is vectored by the lone star tick (amblyomma americanum). lyme-like illness lesions, which are similar to the erythema migrans rash of lyme disease, tend to have lymphocytic dermal infiltrates. with the exception of borrelia lonestari, the possible causative agent or agents of lyme-like illness have not been cultured. more research is needed to fully understand this newly recognized zoonosis. clini ...200818452807
spatial distribution and impact of cattle-raising on ticks in the pantanal region of brazil by using the co(2) tick trap.this study evaluates the impact of cattle-raising on ticks associated with wildlife in the pantanal region of brazil, by trapping free-living ticks using a co(2) tick trap. the traps were equally distributed in two areas: a 600-ha protected area (pa) and the nhumirim ranch (nr). both areas are contiguous and located at the sub-region of nhecolândia (18 degrees 59's; 56 degrees 39'w), pantanal, brazil. in each area, four habitat types were selected: cerrado (tropical savanna), forest patches, lak ...200818454288
new morphological data on fat bodies of semi-engorged females of amblyomma cajennense (acari: ixodidae).the present ultramorphological, histological and ultrastructural study on the fat body of semi-engorged females of amblyomma cajennense revealed that this tissue is diffuse and consists of strands of cells surrounding the tracheal trunks. morphometric analysis showed that the cellular and nuclear areas of round-shaped trophocytes are larger than those of cuboidal trophocytes, indicating that the arrangement of the former provides more contact area with the haemolymph. in this species, the fat bo ...200818215525
two usa ehrlichia spp. cause febrile illness in goats.ehrlichia spp. are not currently recognized as a cause of illness in goats in the usa, but three ehrlichia are enzootic in lone star ticks (amblyomma americanum) in the eastern usa, and related bacteria in other countries cause illness in goats. we exposed naïve goats to ehrlichia-infected amblyomma and demonstrated that infection and clinical illness can be caused by two usa species, e. ewingii and the recently discovered panola mountain ehrlichia sp. clinical features in all five goats are des ...200818328644
more about the role of 2,6-dichlorophenol in tick courtship: identification and olfactometer bioassay in amblyomma cajennense and rhipicephalus sanguineus.this study aimed to identify 2,6-dichlorophenol (2,6-dcp) in amblyomma cajennense and to evaluate its role in a. cajennense and rhipicephalus sanguineus courtship. hexanic extract from attractive females was purified by solid phase extraction and the phenol was identified by the single ion monitoring method using gc/ms. in an olfactometer, the responses of a. cajennense and r. sanguineus males to females, control rubber septa or rubber septa impregnated with 2,6-dcp at 50, 500, and 5000 ng, resp ...200818368237
expressed sequence tags (ests) from the salivary glands of the tick amblyomma cajennense (acari: ixodidae).the neotropical tick amblyomma cajennense is a significant pest to domestic animals, the most frequently human-biting tick in south america and the main vector of brazilian spotted fever (caused by rickettsia rickettsii), a deadly human disease. the purpose of this study is to characterize the adult a. cajennense salivary gland transcriptome by expressed sequence tags (ests). we report the analysis of 1754 clones obtained from a cdna library, which reveal mainly transcripts related to proteins i ...200818243270
serosurvey of rickettsia spp. in dogs and humans from an endemic area for brazilian spotted fever in the state of são paulo, brazil.the present study provides a rickettsial serosurvey in 25 dogs and 35 humans in an endemic area for brazilian spotted fever in the state of são paulo, where the tick amblyomma aureolatum is the main vector. testing canine and human sera by indirect immunofluorescence against four rickettsia antigens (r. rickettsii, r. parkeri, r. felis and r. bellii) showed that 16 (64%) of canine sera and 1 (2.8%) of human sera reacted to at least one of these rickettsial antigens with titers >0r= 64. seven can ...200818278271
detection of two bartonella tamiae-like sequences in amblyomma americanum (acari: ixodidae) using 16s-23s intergenic spacer region-specific primers.four hundred and sixty-six questing amblyomma americanum (l.) (acari: ixodidae) from carolina county, va, and 98 questing a. americanum from chatham county, nc, were screened by polymerase chain reaction (pcr) for the bartonella 16s-23s intergenic spacer region. two amplicons, approximately 270-280 bp, were detected in two ticks from virginia. based upon pcr and sequencing, an adult male and adult female tick harbored dna sequences closely related to bartonella tamiae (dq395180). bartonella dna ...200818283962
rickettsia amblyommii infecting amblyomma americanum larvae.polymerase chain reaction analysis of amblyomma americanum adults, nymphs, and larvae from aberdeen proving ground, md (apg), revealed a very high prevalence of a spotted fever group (sfg) rickettsia. restriction fragment length polymorphism (rflp) and sequence analysis identified "rickettsia amblyommii." this organism is not yet described or well studied, and its pathogenicity is unknown; however, investigations of the organism are warranted because of its high prevalence in a. americanum. this ...200818171102
molecular and parasitological survey of hepatozoon canis (apicomplexa: hepatozoidae) in dogs from rural area of sao paulo state, brazil.hepatozoon canis is a protozoan that infects dogs and is transmitted by the ingestion of the brown dog tick, rhipicephalus sanguineus. two distinct species of hepatozoon genus can infect dogs, h. canis and h. americanum. routine tests to detect the disease are based on direct examination of gametocytes on giemsa-stained blood smears. the objectives of this study were the investigation of infection prevalence in rural area dogs, the comparison of diagnostics by blood smear examination and polymer ...200818188597
biological aspects of amblyomma brasiliense (acari: ixodidae) under laboratory conditions.although amblyomma brasiliense aragão 1908 has been reported as one of the most aggressive ticks to humans in brazil, information about the biology of this tick species is virtually inexistent. this work reports data on the life cycle of a. brasiliense fed on rabbits and pigs and maintained in an incubator at 20 degrees c, 90% rh and 12 h of light for off-host development. tick yield of adult females fed on pigs and rabbits was 81.2% and 58.3%, respectively. females fed on pigs had mean engorgem ...200818188669
bothriocroton oudemansi (neumann, 1910) n. comb. (acari: ixodida: ixodidae), an ectoparasite of the western long-beaked echidna in papua new guinea: redescription of the male and first description of the female and nymph.specimens of amblyomma oudemansi (neumann, 1910) were collected in papua new guinea from an endangered monotreme, zaglossus bruijni (peters & doria), the western long-beaked echidna. these ticks were compared morphologically and molecularly with species formerly assigned to aponomma neumann, 1899 (now included in bothriocroton keirans, king, & sharrad, 1994 or amblyomma koch, 1844), and a phylogeny was generated. based on our results, we reassign this tick to bothriocroton, as b. oudemansi (neum ...200818210218
african tick bite fever--papulovesicular exanthem with fever after staying in south the wake of expanding international tourism, rickettsioses are increasingly observed also in central europe. african tick bite fever is a recently described, acute febrile illness with characteristic skin lesions. it is caused by rickettsia africae, which is transmitted to humans by ticks of the amblyomma genus. a 60-year-old woman presented with a papulovesic-ular exanthem, fever, and headache after returning from south africa. a purple nodule with central necrosis ("tache noire"or "inoculat ...200818021248
climate changes and suitability for the ticks amblyomma hebraeum and amblyomma variegatum (ixodidae) in zimbabwe (1974-1999).the spread of amblyomma hebraeum has been reported in zimbabwe. at the same time there was little or no spread in the distribution of amblyomma variegatum. this paper examines the climatic cycles and their trends in the period 1974-1999 with a view to explaining the abiotic causes of this spread, and of forecasting the likely tendency in climate suitability for both tick species. an annual data-set of rainfall and air temperature was used as a source for climate, together with a habitat-modeling ...200818083309
redescription of amblyomma varium koch, 1844 (acari: ixodidae) based on light and scanning electron microscopy.amblyomma varium koch, 1844 is a neotropical tick, known as the 'sloth's giant tick', with records from southern central america to argentina. it is found almost exclusively on mammals of the families bradypodidae and magalonychidae (xenarthra). differences exist in discussions with regard to the dentition of the female hypostome being either 3/3 or 4/4. the male was also originally described as having a short spur on coxa iv, but some specimens recently collected from different brazilian locali ...200818038200
detection of alpha and gamma-proteobacteria in amblyomma triste (acari: ixodidae) from uruguay.amblyomma triste is the most prevalent tick species reported in human tick bites in uruguay and has been found to be infected with rickettsia parkeri, but no other microorganisms have been reported from this tick. a sample of 254 adults of a. triste was collected by flagging on vegetation in suburban areas in southern uruguay. pools of five ticks were assembled and a screening for the dna from the resulting 51 pools was realized by pcr assays using primers for amplifying a fragment of 16s rrna g ...200818071910
biological parameters of ticks (amblyomma cajennense fabricius, 1787) under field and laboratory conditions in pedro leopoldo, state of minas gerais, brazil.this study evaluated the biological parameters of the duration of the pre-oviposition and egg incubation periods and maximum survival of unfed larvae, under field and laboratory conditions, with the aim of providing support for more rational measures for controlling amblyomma cajennense. this study was conducted at the experimental farm of the veterinary school of the federal university of minas gerais. every 14 days, from september 1997 to march 1998 and from october 1998 to april 1999, six net ...200820059808
[seasonal dynamics of amblyomma ticks (acari:ixodidae) in an urban park of londrina city, parana, brazil].ticks are important to public health due to diseases they transmit to animals and humans and, economic losses they cause to livestock production. among other agents, such as babesia, ehrlichia, anaplasma, the rickettsia are the most important pathogens transmitted by ticks in brazil. worldwide there are about 870 tick species described and, of these, 55 species were already reported in brazil, being the genus amblyomma the most numerous with 33 species. the a. cajennense is the principal tick in ...200820059815
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