Publications

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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
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
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
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
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
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
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
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
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
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
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
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
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
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
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 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
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
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
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
rickettsia species infecting amblyomma cooperi ticks from an area in the state of são paulo, brazil, where brazilian spotted fever is endemic.owing to the potential role of the tick amblyomma cooperi in the enzootic cycle of rickettsia rickettsii, the etiologic agent of brazilian spotted fever (bsf), this study evaluated infection by rickettsia species in a. cooperi ticks collected from an area in brazil where bsf is endemic. among a total of 40 a. cooperi adult ticks collected in an area of bsf endemicity in the state of são paulo, pcr analysis detected dna of rickettsia bellii in 16 ticks (40%), and 3 other ticks (7.5%) were positiv ...200414715737
rickettsia parkeri: a newly recognized cause of spotted fever rickettsiosis in the united states.ticks, including many that bite humans, are hosts to several obligate intracellular bacteria in the spotted fever group (sfg) of the genus rickettsia. only rickettsia rickettsii, the agent of rocky mountain spotted fever, has been definitively associated with disease in humans in the united states. herein we describe disease in a human caused by rickettsia parkeri, an sfg rickettsia first identified >60 years ago in gulf coast ticks (amblyomma maculatum) collected from the southern united states ...200414999622
ehrlichia ruminantium grows in cell lines from four ixodid tick genera.continuous cell lines from the ticks amblyomma variegatum, boophilus decoloratus, boophilus microplus, hyalomma anatolicum anatolicum, ixodes scapularis, ixodes ricinus and rhipicephalus appendiculatus were tested for ability to support growth of the rickettsial pathogen ehrlichia (previously cowdria) ruminantium. five e.ruminantium isolates, from west africa, south africa and the french west indies, were used. twelve tick cell lines were inoculated with e.ruminantium derived either from culture ...200415053931
occurrence of the gulf coast tick (acari: ixodidae) on wild and domestic mammals in north-central oklahoma.parasitic life stages of amblyomma maculatum koch were collected from domestic cattle and several species of wild mammals during a 3.5-yr study (may 1998-october 2001) in north-central oklahoma. adult ticks were the predominant life stage collected from cattle, white-tailed deer, coyotes, and raccoons, whereas only immature ticks were collected from cotton rats and white-footed mice. the prevalence of adult a. maculatum on white-tailed deer (n = 15) examined in june, july, and august 1998 was 80 ...200415061275
comparative activity of deet and ai3-37220 repellents against the ticks ixodes scapularis and amblyomma americanum (acari: ixodidae) in laboratory bioassays.the repellents n,n-diethyl-3-methylbenzamide (deet) and racemic 2-methylpiperidinyl-3-cyclohexene-1-carboxamide (ai3-37220) were evaluated using two different laboratory bioassays to determine their relative effectiveness against host-seeking nymphs of the blacklegged tick, ixodes scapularis say, and the lone star tick, amblyomma americanum (l.). in a petri dish bioassay, ticks were released within a ring of repellent on a horizontal filter paper disk. in the second bioassay, ticks were allowed ...200415061285
climate change decreases habitat suitability for some tick species (acari: ixodidae) in south africa.models predicting current habitat availability for four prominent tick species in africa (boophilus decoloratus, amblyomma hebraeum, rhipicephalus appendiculatus and hyalomma truncatum) were constructed using remotely sensed information about abiotic variables and a point-to-point similarity metric. year-to-year variations in the forecasted habitat suitability over the period 1983-2000 show a clear decrease in habitat availability, which is attributed primarily to increasing temperature in the r ...200312967169
american canine hepatozoonosis.american canine hepatozoonosis is an emerging, tick-transmitted infection of domestic dogs caused by a recently recognized species of apicomplexan parasite, hepatozoon americanum. the known definitive host of the protozoan is the gulf coast tick, amblyomma maculatum. presently recognized intermediate hosts include the domestic dog and the coyote, canis latrans. laboratory-reared larval or nymphal a. maculatum can be infected readily by feeding to repletion on a parasitemic intermediate host; spo ...200312885206
american canine hepatozoonosis.hepatozoon americanum infection is an emerging tickborne disease in the southern united states. this organism causes a very different and much more severe disease than does hepatozoon canis, the etiologic agent of canine hepatozoonosis in the rest of the world. h americanum is transmitted through ingestion of the definitive host, amblyomma maculatum (the gulf coast tick). clinical signs of american canine hepatozoonosis tend to wax and wane over time and may include lameness, weakness, pain, mus ...200312910749
detection by two enzyme-linked immunosorbent assays of antibodies to ehrlichia ruminantium in field sera collected from sheep and cattle in ghana.two serological tests for detection of antibodies to ehrlichia (previously cowdria) ruminantium, the causative agent of heartwater, were compared by using field sera collected from sheep and cattle as part of serosurveys in ghana. sera selected as either negative or positive by a new polyclonal competitive enzyme-linked immunosorbent assay (pc-elisa) were tested by the indirect map1-b elisa. cutoff values of 14 percent positivity (14 pp) for both ruminant species were obtained for the map1-b eli ...200312965927
evaluation of a prototype ehrlichia chaffeensis surveillance system using white-tailed deer (odocoileus virginianus) as natural sentinels.the natural history of ehrlichia chaffeensis, the causative agent of human monocytotropic ehrlichiosis, includes the lone star tick (lst, amblyomma americanum) as a vector and white-tailed deer (wtd; odocoileus virginianus) as both a natural reservoir of e. chaffeensis and a major host of lst. the goal of the current study was to implement and evaluate a prototype surveillance system to delineate the geographic distribution of e. chaffeensis using wtd as natural sentinels. to accomplish this goa ...200314733672
endocannabinoids and related fatty acid amides, and their regulation, in the salivary glands of the lone star tick.the salivary glands and saliva from the lone star tick amblyomma americanum (l.) were analyzed for the presence of the two endogenous agonists of cannabinoid receptors, n-arachidonoylethanolamine (anandamide) and 2-arachidonoylglycerol (2-ag), as well as of the anandamide congener, n-palmitoylethanolamine (pea), an anti-inflammatory and analgesic mediator that is inactive at cannabinoid receptors. two very sensitive mass-spectrometric techniques were used for this purpose. both 2-ag and pea, as ...200312842196
evaluation of transovarial transmission and transmissibility of ehrlichia chaffeensis (rickettsiales: anaplasmataceae) in amblyomma americanum (acari: ixodidae).it has long been assumed that ehrlichia chaffeensis (anderson, dawson & wilson), is not transmitted transovarially in the lone star tick vector amblyomma americanum (l.). to test this hypothesis, three beagle dogs, canis familiaris (l.) (carnivora: canidae), were subcutaneously infected with e. chaffeensis (arkansas strain). uninfected nymphal lone star ticks were placed on the infected dogs and allowed to feed to repletion. these nymphal ticks were allowed to molt, and five of five adult female ...200314765684
ixodid tick species recovered from domestic dogs in japan.the species of ixodid ticks (acari: ixodidae) recovered from domestic dogs in japan between september to november 2000 and april to june 2001 were identified. a total of 4122 ticks, including 1624 larvae, 1200 nymphs, 1016 females and 282 males were removed from 1221 dogs during these periods. haemaphysalis longicornis (neumann) was the most frequently found (40.3% of dogs), followed by h. flava (neumann) (16.1% of dogs), rhipicephalus sanguineus (latreille) (4.8% of dogs) and ixodes ovatus (neu ...200312680923
ecological analysis of acari recovered from coprolites from archaeological site of northeast brazil.coprolite samples of human and animal origin from the excavations performed at the archaeological site of furna do estrago, at brejo da madre de deus in the state of pernambuco, brazil and sent to the paleoparasitology laboratory at escola nacional de saúde pública-fiocruz, rio de janeiro, were analyzed for mites. after rehydratation and sedimentation of the coprolites, the alimentary contents and the sediments were examined and the mites collected and prepared in definitive whole mounts, using ...200312687780
attraction of amblyomma variegatum (ticks) to the attraction-aggregation-attachment-pheromone with or without carbon dioxide.the responses of adult amblyomma variegatum ticks released from various distances to different doses of the synthetic attraction-aggregation-attachment pheromone (aaap) (made up of orthonitrophenol, methyl salicylate and nonanoic acid in paraffin oil), dispensed from the center of circular field plots, were studied in the presence or absence of elevated levels of co2. up to 90% of the ticks released were attracted to the pheromone source in the presence of co2 within 3h. co2 alone was unattracti ...200314580064
hosts and distribution of amblyomma auricularium (conil 1878) and amblyomma pseudoconcolor aragão, 1908 (acari: ixodidae).collections of amblyomma auricularium (conil 1878) and a. pseudoconcolor aragão, 1908 are discussed in relation to distribution and hosts. three tick collections (two from argentina and a third from the usa) house a total of 574 a. auricularium (307 males, 162 females, 73 nymphs and 32 larvae) and 179 a. pseudoconcolor (96 males, 74 females, 4 nymphs and 5 larvae). apart from an adult a. pseudoconcolor found on a bird, nothura maculosa temminck, 1815, all ticks were found on mammals. the great m ...200314580065
experimental infection of lone star ticks, amblyomma americanum (l.), with rickettsia parkeri and exposure of guinea pigs to the agent.the maculatum agent, rickettsia parkeri (a member of the spotted fever group rickettsiae), was inoculated into a colony of the lone star tick, amblyomma americanum, and followed for two tick generations. in addition, guinea pigs were exposed to the agent by direct injection and by feeding infected ticks on them. eighty (53%) of 150 nymphal a. americanum that were inoculated with suspensions of r. parkeri were positive by hemolymph test and fluorescent antibody test for rickettsial infection when ...200314596284
amblyomma aureolatum (pallas, 1772) and amblyomma ovale koch, 1844 (acari: ixodidae): hosts, distribution and 16s rdna sequences.dna sequences of amblyomma aureolatum (pallas, 1772) and amblyomma ovale koch, 1844 were obtained to determine genetic differences between these tick species. collections of these species are discussed in relation to distribution and hosts. seven ticks collections (four from brazil, one from argentina, one from uruguay and one from usa) house a total of 1272 a. aureolatum (224 males, 251 females, 223 nymphs and 574 larvae) and 1164 a. ovale (535 males, 556 females, 66 nymphs and 7 larvae). the l ...200312719142
exotic ticks introduced into the united states on imported reptiles from 1962 to 2001 and their potential roles in international dissemination of diseases.since 1962, a total of 29 species of exotic ticks have been introduced into the united states on imported reptiles, with 17 species from the genus amblyomma, 11 from the genus aponomma and one from the genus hyalomma. in the absence of measures to control introduction of these importations, some exotic tick species will develop breeding colonies and become established as indigenous species and some tickborne diseases may be introduced to wreak havoc among susceptible native populations. however, ...200312719143
rna interference in ticks: a study using histamine binding protein dsrna in the female tick amblyomma americanum.rna interference (rnai), a gene silencing process, has been recently exploited to determine gene function by degrading specific mrnas in several eukaryotic organisms. we constructed a double stranded rna (dsrna) from a previously cloned putative amblyomma americanum histamine binding protein (hbp) to test the significance of using this methodology in the assessment of the function and importance of gene products in ectoparasitic ticks. the female salivary glands incubated in vitro with hbp dsrna ...200312752664
acquired resistance of horses to amblyomma cajennense (fabricius, 1787) ticks.acquired immunity of horses to larvae, nymphs and adults of the amblyomma cajennense tick was evaluated through three consecutive experimental infestations of tick-bite naïve hosts. data from these infestations were compared to those from field-sensitized horses and donkeys. it was observed that tick-bite naïve horses developed a low level of resistance after two infestations as shown by a significant decrease in larval yield and a tendency for lower engorged weight of nymphs during third infest ...200314637029
in vitro assays for repellents and deterrents for ticks: differing effects of products when tested with attractant or arrestment stimuli.most in vivo and in vitro tests with repellents or deterrents against ticks have not considered which sensory channel is being targeted. we have recorded the responses of two hard tick species (acari: ixodidae) in vitro to determine if such products can disrupt the perception of an attractant in a repellent assay or the perception of an arrestment stimulus in a deterrent assay. ethyl butylacetylaminopropionate (ebaap), n,n-diethyl-methyl-benzamide (deet), permethrin and indalone were chosen to t ...200314651650
seasonal dynamics of the cayenne tick, amblyomma cajennense on horses in brazil.the population dynamics of all stages of the cayenne tick, amblyomma cajennense (fabricius) (acari: ixodidae) on horses was evaluated over a period of 2 years in the district of pedro leopoldo, state of minas gerais, brazil. every 14 days, the left side of 20 horses was brushed for collection of immature stages; counts of adults were also undertaken. infestation by larvae was detected from april to august, whereas nymphs were observed from june to october. infestation by adults was detected thro ...200314651655
efficacy of two 65% permethrin spot-on formulations against induced infestations of ctenocephalides felis (insecta: siphonaptera) and amblyomma americanum (acari: ixodidae) on beagles.the efficacy of two formulations of a topically applied 65% permethrin spot-on (defend exspot treatment for dogs, schering-plough animal health) was evaluated against experimental infestations of the cat flea ctenocephalides felis and the lone star tick amblyomma americanum in dogs. eighteen dogs were randomly assigned to treatment with 65% permethrin in either diethylene glycol monomethyl ether (dgme; original formulation) or propylene glycol monomethyl ether (pgme) or to be untreated as a cont ...200312756635
brazilian distribution of amblyomma varium koch, 1844 (acari: ixodidae), a common parasite of sloths (mammalia: xenarthra).amblyomma varium, commonly known in brazil as the "carrapato-gigante-da-pregui a" (sloth's giant tick) is found from southern central america to argentina. the present study adds information on the geographical distribution of a. varium, as well as on their hosts, based on material deposited in the main brazilian collections and on the available literature. eighty-two vials, containing 191 adult specimens, deposited in five acari collections between 1930 and 2001, were examined. these vials incl ...200312563481
transstadial transfer of west nile virus by three species of ixodid ticks (acari: ixodidae).larvae and/or nymphs of four species of ixodid ticks, ixodes scapularis say, amblyomma americanum (l.), dermacentor andersoni stiles, and dermacentor variabilis say, were fed to completion on laboratory hamsters or mice which had been inoculated with a west nile (wn) virus isolate from culex pipiens l. captured in connecticut usa. maximum titers in mice and hamsters were approximately 5 and two logs, respectively, lower than recorded (10 logs) in a naturally infected american crow, corvus brachy ...200314680122
a method for extraction and analysis of high quality genomic dna from ixodid ticks.currently, no published methods describe the extraction of high molecular weight genomic dna from ixodid ticks (acari: ixodidae) and commonly used methods of extraction are not well adapted for use with members of this family. a method for extraction of minimally degraded genomic dna from ixodid ticks that can be completed in one or two days is described. the method produces dna which is of sufficient size (>24 kb) for use in southern analysis and which is readily digestible by restriction endon ...200312823841
seasonal fluctuation of parasitic infestation in donkeys (equus asinus) in oodi village, kgatleng district, botswana.during the period march to september 2000, a study was conducted in oodi village, kgatleng district, botswana, to investigate the seasonal fluctuation of internal, external and blood parasites of donkeys. twelve adult donkeys were randomly selected from a farmer with a herd of 15 donkeys. monthly visits were made to the farmer when the donkeys were examined for parasites. the only ectoparasites recovered from the donkeys were instars of various tick species. the most prevalent tick was rhipiceph ...200312836744
survey of ticks collected in mississippi for rickettsia, ehrlichia, and borrelia species.from november 1999 through october 2000, we tested ticks collected from vegetation as well as from deer, dogs, and humans for spotted fever group (sfg) rickettsiae, ehrlichia chaffeensis, and borrelia spp. spirochetes. a total of 149 adult ticks representing four species was collected from 11 collection sites from southwestern to northern mississippi. amblyomma americanum was most commonly collected (n=68), followed by ixodes scapularis (n=53). the bird tick, ixodes brunneus (usually rare), was ...200314714667
detection of ehrlichia spp., anaplasma spp., rickettsia spp., and other eubacteria in ticks from the thai-myanmar border and vietnam.a total of 650 ticks, including 13 species from five genera, were collected from animals, from people, or by flagging of the vegetation at sites on the thai-myanmar border and in vietnam. they were tested by pcr to detect dna of bacteria of the order rickettsiales: three anaplasma spp. were detected in ticks collected in thailand, including (i) anaplasma sp. strain anda465, which was considered a genotype of anaplasma platys (formerly ehrlichia platys) and which was obtained from dermacentor aur ...200312682151
persistence of hepatozoon americanum (apicomplexa: adeleorina) in a naturally infected dog.to determine the persistence of hepatozoon americanum in a naturally infected dog, skeletal muscle biopsies were performed at approximately 6-mo intervals over a period of 5.5 yr, and the samples were examined for presence of lesions of american canine hepatozoonosis (ach). nymphal amblyomma maculatum (gulf coast tick) were allowed to feed to repletion on the dog periodically over the 5.5-yr period, and adult ticks were dissected and examined for presence of h. americanum oocysts. with 3 excepti ...200312880267
selection assisted by a bola-dr/dq haplotype against susceptibility to bovine dermatophilosis.bovine dermatophilosis is a severe skin infection of tropical ruminants inducing a severe loss in productivity and a 15% mortality rate. this disease is caused by the actinomycete bacterium dermatophilus congolensis associated with the tick amblyomma variegatum. currently there are no prospects for a vaccine, and acaricide or antibiotic control is hampered by the development of chemoresistance. animal breeders have observed that dermatophilosis susceptibility seems to be determined genetically, ...200312927091
a survey for spotted fever group rickettsiae and ehrlichiae in amblyomma variegatum from st. kitts and nevis.eighty-nine amblyomma variegatum ticks were collected from the islands of st. kitts and nevis in the caribbean and preserved in 70% ethanol or local rum. after being washed in sterile water, their dna was extracted and analyzed by a polymerase chain reaction (pcr) for dna of spotted fever group rickettsiae and ehrlichiae. none of the tested ticks was positive in a pcr assay using the primers 16s ehrd and 16s ehrr for the 16s rrna gene of ehrlichia spp.. forty-one percent of the a. variegatum (36 ...200312932098
ticks (acari: ixodidae) on wild marsh-deer (blastocerus dichotomus) from southeast brazil: infestations before and after habitat loss.the lake from porto-primavera hydroelectric power station inundated an area of 2,200 km2 at the border of são paulo and mato-grosso do sul states, brazil. infestations by ticks were evaluated on 135 marsh deer, blastocerus dichotomus (illiger), captured before and after inundation. ticks were collected for identification, and infestation level of animals was assessed by scoring. deer were divided into four groups according to capture location and temporal relation to the inundation. groups 1, 2, ...200312943103
african tick bite fever.african tick bite fever is an acute febrile illness that is frequently accompanied by headache, prominent neck muscle myalgia, inoculation eschars, and regional lymphadenitis. the disease is caused by rickettsia africae, a recently identified spotted fever group rickettsia, which is transmitted by ungulate ticks of the amblyomma genus in rural sub-saharan africa and the french west indies. whereas reports on african tick bite fever in indigenous populations are scarce, the number of reported cas ...200312954562
the ascendancy of amblyomma americanum as a vector of pathogens affecting humans in the united states.until the 1990s, amblyomma americanum was regarded primarily as a nuisance species, but a tick of minor importance as a vector of zoonotic pathogens affecting humans. with the recent discoveries of ehrlichia chaffeensis, ehrlichia ewingii, and "borrelia lonestari," the public health relevance of lone star ticks is no longer in question. during the next 25 years, the number of cases of human disease caused by a. americanum-associated pathogens will probably increase. based on current trajectories ...200312414740
ixodid ticks of angora and boer goats, grysbok, common duikers, kudus and scrub hares in valley bushveld in the eastern cape province, south africa.at monthly intervals from february 1983 to january 1984 two angora goats, two boer goats, one grysbok, raphicerus melanotis, one common duiker, sylvicapra grimmia, one greater kudu, tragelaphus strepsiceros, and four scrub hares, lepus saxatilis, were killed on a farm in valley bushveld in the eastern cape province, south africa and examined for ticks. seven ixodid tick species were collected, of which rhipicephalus glabroscutatum followed by amblyomma hebraeum and rhipicephalus oculatus were th ...200312967172
survey of ixodid tick species on domestic cats in japan.various species of ixodid ticks, attached to domestic cats in japan, were identified in spring (april to june) and autumn (september to november). in the spring, a total of 282 ticks, including 61 larvae, 70 nymphs, 127 females and 24 males were collected from 126 cats. of these, 264 were identified up to the species level. in the spring, haemaphysalis longicornis was the most frequently (39.7%, 50/126) found tick species on feline hosts, followed by ixodes ovatus (35.0%, 44/126), ixodes nippone ...200312531297
ticks (acari: ixodidae) on wild animals from the porto-primavera hydroelectric power station area, brazil.from june 2000 to june 2001, a total of 741 ticks were collected from 51 free-living wild animals captured at the porto-primavera hydroelectric power station area, located alongside an approximately 180 km course of the paran river, between the states of s o paulo and mato grosso do sul, comprising 9 species of 3 genera: ambly-omma (7 species), boophilus (1) and anocentor (1). a total of 421 immature amblyomma ticks were reared in laboratory until the adult stage, allowing identification of the ...200312563479
ehrlichia chaffeensis: a prototypical emerging pathogen.ehrlichia chaffeensis is an obligately intracellular, tick-transmitted bacterium that is maintained in nature in a cycle involving at least one and perhaps several vertebrate reservoir hosts. the moderate to severe disease caused by e. chaffeensis in humans, first identified in 1986 and reported for more than 1,000 patients through 2000, represents a prototypical "emerging infection." knowledge of the biology and natural history of e. chaffeensis, and of the epidemiology, clinical features, and ...200312525424
detection of borrelia lonestari in amblyomma americanum (acari: ixodidae) from tennessee.genetic sequences characteristic of borrelia lonestari (barbour et al. 1996) were detected in two pools of adult amblyomma americanum (l.) from tennessee, corresponding to an estimated minimum field infection rate of 8.4 infected ticks/1000 adults. dna amplification was conducted using primers derived from the b. lonestari flagellin gene that would also amplify borrelia burgdorferi (johnson, schmid, hyde, steigerwalt, and brenner). species-specific, internal probes were then used to differentiat ...200312597661
larval behavioral diapause regulates life cycle of amblyomma cajennense (acari: ixodidae) in southeast brazil.previous studies have determined that amblyomma cajennense (f.) produces one generation per year in southeastern brazil. larvae predominate from april to july, nymphs from july to october, and adults from october to march. in the current study, we observed engorged females, their eggs, and respective larvae in the field. engorged females were released in grass plots under natural conditions, at monthly intervals, from october 2000 to march 2001. preoviposition periods lasted 1-2 wk, and mean egg ...200312693845
molecular evidence for novel tick-associated spotted fever group rickettsiae from thailand.ticks are of considerable medical and veterinary importance because they directly harm the host through their feeding action and indirectly through vectoring many bacterial pathogens. despite many ticks being known from thailand, very little is known about the bacteria they may harbor. we report here the results of a survey of tick-associated bacteria in thailand. a total of 334 individuals representing 14 species of ticks in five genera were collected from 10 locations in thailand and were exam ...200312693853
repellent efficacy of deet and kbr 3023 against amblyomma hebraeum (acari: ixodidae).the bont tick, amblyomma hebraeum koch, is the principal vector of rickettsia africae, the agent of african tick bite fever, in southern africa. in contrast to most other hard ticks, members of the genus amblyomma exhibit a characteristic attack host-seeking behavior. the efficacy of topically applied 20% lotions of deet (diethyl-3-methylbenzamide), the currently considered reference repellent substance, and kbr 3023, a recently developed piperidine compound, was evaluated against laboratory-rea ...200312693855
effect of fast protein liquid chromatography fractionated salivary gland extracts from different ixodid tick species on interleukin-8 binding to its cell receptors.interleukin-8 plays a critical role in inflammatory processes. hence generation of molecules with anti-il-8 activity is likely to be important for successful feeding and for survival of the ticks. anti-il-8 activity was studied in saliva of three ixodid tick species--dermacentor reticulatus (fabricius, 1794), rhipicephalus appendiculatus neumann, 1901, and amblyomma variegatum (fabricius, 1794). the greatest activity was shown in saliva prepared from d. reticulatus. the activity was attributed t ...200312735728
spotted fever group rickettsiae in ticks from the masai mara region of kenya.we have identified for the first time rickettsia africae, and the ticks that harbored them, in kenya. a total of 5,325 ticks were collected from vegetation, livestock, and wild animals during two field trips to southwestern kenya. most were immature forms (85.2%) belonging to the genera amblyomma or rhipicephalus. the adults also included representatives from the genus boophilus. ticks were assessed for rickettsial dna by a polymerase chain reaction (pcr) using primers for the spotted fever grou ...200312812343
ehrlichiae and ehrlichial diseases in china.the various ticks collected from different areas of china were examined for the existence of ehrlichial agents by polymerase chain reaction (pcr) with genus- or species-specific primers designed on the basis of ehrlichial 16s rrna genes and sequence analyses. in southern china, e. chaffeensis was detected in amblyomma testudinarium ticks from infested cattle, haemaphysalis yeni ticks from hare, and ixodes ovatus ticks from muntiacus reevesi. e. canis was identified in rhipicephalus sanguineus ti ...200312860598
rickettsia honei: a spotted fever group rickettsia on three continents.rickettsia honei (also known as strain tt-118) has been detected on three continents. originally isolated in thailand in 1962 (and confirmed in 2001), it has also been detected on flinders island (australia) in 1993 and in texas (usa) in 1998. on each continent it has been associated with a different species of tick. the original isolate (thai tick typhus strain tt-118) was from a pool of larval ixodes and rhipicephalus ticks. later it was detected in i. granulatus from rattus rattus. its pathog ...200312860601
rickettsiosis caused by rickettsia conorii in uruguay.the first three human cases of rickettsiosis caused by rickettsia conorii in montevideo, uruguay were described in 1990. all of them showed an initial papulosquamous lesion on the scalp from a canine tick bite (amblyomma triste). at the same time, fever and regional adenopathies were observed. serological diagnosis was made by the indirect igm immunofluorescent technique on glass smears of r. conorii (biomerieux laboratories, france). all patients had a benign disease course after been treated w ...200312860638
meteorologically mediated diurnal questing of ixodes scapularis and amblyomma americanum (acari: ixodidae) nymphs.questing ixodes scapularis say and amblyomma americanum (l.) nymphs were collected in the field by drag sampling to determine whether ticks would be collected in greater numbers during certain times of the day and under certain ambient meteorological conditions. ticks were collected hourly for 16 h on 4 d and counts were contrasted with simultaneous measurements of ambient temperature and relative humidity, and with similar measurements made within the leaf litter. peak numbers of questing i. sc ...200314680102
dna evidence of borrelia lonestari in amblyomma americanum (acari: ixodidae) in southeast missouri.amblyomma americanum collected near lake wappapello, missouri, tested positive for borrelia lonestari using polymerase chain reaction and sequence analyses of b. lonestari 16s rrna and flagellin (flab) genes. twelve pools containing a total of 214 nymph or adult ticks contained evidence of infection with b. lonestari (minimum prevalence 5.6%). these data suggest that persons in southeast missouri are at risk for exposure to b. lonestari after a. americanum tick bite, a possible cause of erythema ...200314680133
ticks (ixodida: ixodidae) parasitising humans in uruguay.during routine collections between november 1999 and november 2002, three species of tick (amblyomma tigrinum, amblyomma triste and rhipicephalus sanguineus) were found on humans in southern uruguay. the finding of r. sanguineus and a. triste on humans is of particular concern because these tick species may be involved in the transmission of the pathogens causing human rickettsioses, a type of disease already known to occur in uruguay.200314613636
comparing the detection of exposure to ehrlichia ruminantium infection on a heartwater-endemic farm by the pcs20 polymerase chain reaction assay and an indirect map1-b enzyme linked immunosorbent assay.detection of heartwater is not always easy especially because all the serological assays so far available either have poor sensitivity or specificity. the indirect map-1b elisa has been reported to be the most specific test for heartwater, although it does also detect antibodies to some closely related ehrlichial agents. this study was undertaken to compare two methods for the detection of heartwater infection caused by the ehrlichial agent ehrlichia (cowdria) ruminantium. fifteen cattle on a he ...200314621319
evidence of borrelia lonestari dna in amblyomma americanum (acari: ixodidae) removed from humans.we used a nested pcr with borrelia flagellin gene (flab) primers and dna sequencing to determine if borrelia lonestari was present in amblyomma americanum ticks removed from military personnel and sent to the tick-borne disease laboratory of the u.s. army center for health promotion and preventive medicine. in our preliminary investigation, we detected borrelia sequences in 19 of 510 a. americanum adults and nymphs from ft. a. p. hill, va. during the 2001 tick season, the flab primers were used ...200314662940
a cautionary note: survival of nymphs of two species of ticks (acari: ixodidae) among clothes laundered in an automatic washer.host-seeking ticks often remain on clothing of persons returning home from work or recreation in tick habitats, and can pose at least a temporary risk to people and pets in these homes. laundering clothing has been one of the recommendations to reduce tick exposure. host-seeking lone star tick, amblyomma americanum (l.), and blacklegged tick, ixodes scapularis say, nymphs confined in polyester mesh packets, were included with laundry in cold, warm, and hot wash cycles of an automatic clothes was ...200314596290
[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
american canine hepatozoonosis.american canine hepatozoonosis (ach) is a tick-borne disease that is spreading in the southeastern and south-central united states. characterized by marked leukocytosis and periosteal bone proliferation, ach is very debilitating and often fatal. dogs acquire infection by ingesting nymphal or adult gulf coast ticks (amblyomma maculatum) that, in a previous life stage, ingested the parasite in a blood meal taken from some vertebrate intermediate host. ach is caused by the apicomplexan hepatozoon a ...200314557294
parasites of domestic and wild animals in south africa. xli. arthropod parasites of impalas, aepyceros melampus, in the kruger national park.ectoparasites were collected from impalas, aepyceros melampus, at four localities within the kruger national park, namely skukuza, in the biyamiti region, crocodile bridge and pafuri. animals were also examined at skukuza during a severe drought and at skukuza and pafuri towards the end of a second drought. parasite burdens were analysed in relation to locality, sex, age class, month and drought. the impalas were infested with 13 ixodid ticks species, including two that were identified only to g ...200312967174
phylogenetic relationships among ehrlichia ruminantium isolates.ehrlichia ruminantium, the causative agent of heartwater, is a tick-borne pathogen infecting ruminants throughout sub-saharan africa and on some caribbean islands. the most reliable test for e. ruminantium is pcr-based, but this gives positive results in some areas free of clinical heartwater and of the known amblyomma spp. tick vectors. to investigate the molecular basis for this finding we have sequenced and carried out phylogenetic analysis of a range of genes from a number of e. ruminantium ...200312860707
life cycle and host specificity of amblyomma triste (acari: ixodidae) under laboratory conditions.we report biological data of two generations of amblyomma triste in laboratory and compared the suitability of different host species. infestations by larval and nymphal stages were performed on guinea pigs (cavia porcellus), chickens (gallus gallus), rats (rattus norvegicus), rabbits (oryctolagus cuniculus), wild mice (calomys callosus), dogs (canis familiaris) and capybaras (hydrochaeris hydrochaeris). infestations by adult ticks were performed on dogs, capybaras and rabbits. tick developmenta ...200314756395
modulation of human lymphocyte proliferation by salivary gland extracts of ixodid ticks (acari: ixodidae): effect of feeding stage and sex.ixodid ticks remain attached to their hosts for several days to weeks. during this extended feeding process new proteins involved in the modulation of host immune responses are expressed in tick salivary glands. in our study a stimulatory or inhibitory effect of salivary gland extracts (sge) of unfed and partially fed female ixodes ricinus (linnaeus, 1758), female and male amblyomma variegatum (fabricius, 1794) and rhipicephalus appendiculatus neumann, 1901 ticks on human lymphocyte proliferatio ...200314971600
amblyomma aureolatum and ixodes auritulus (acari: ixodidae) on birds in southern brazil, with notes on their ecology.between january 1999 and december 2000, 876 bird specimens were captured in three different ecological environments from the reinhard maack park, curitiba, state of paraná, southern brazil. a total of 142 birds (16.2%) were infested with amblyomma aureolatum (pallas 1772) (n=699) and/or ixodes auritulus neumann, 1904 (n=18) ticks. questing a. aureolatum nymphs (n=2) and adults (n=5) were also collected from the soil and the vegetation. none of the i. auritulus were collected off-host. we collect ...200314974693
a ten-year study of tick biting in mississippi: implications for human disease transmission.to determine exactly which tick species bit people in mississippi, information was gathered on ticks involved in human biting cases for the ten-year period, january 1, 1990-december 31, 1999. specimens were identified by the author and, in most cases, confirmed by personnel at the institute of arthropodology and parasitology, georgia southern university. a total of 119 ticks were recovered from 73 humans during the study period. seven tick species were represented; most common included the lone ...200212853269
the argasidae, ixodidae and nuttalliellidae (acari: ixodida): a world list of valid tick names.the world's argasid tick fauna comprises 183 species in four genera, namely argas, carios, ornithodoros and otobius in the family argasidae. the ixodid tick fauna consists of 241 species in the genus ixodes and 442 species in the genera amblyomma, anomalohimalaya, bothriocroton, cosmiomma, dermacentor, haemaphysalis, hyalomma, margaropus, nosomma, rhipicentor and rhipicephalus in the family ixodidae, with the genus boophilus becoming a subgenus of the genus rhipicephalus. the family nuttallielli ...200214570115
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 ...200214570118
immunogenicity of ehrlichia ruminantium grown in tick cell lines.ehrlichia (previously cowdria) ruminantium, the pathogen which causes heart-water in domestic and wild ruminants, can now be propagated in cell lines from one vector (amblyomma variegatum) and five non-vector (ixodes scapularis, i. ricinus, boophilus decoloratus, b. microplus and rhipicephalus appendiculatus) tick species. e. ruminantium isolates from west and south africa and the caribbean vary in their cell line preference, growth patterns and immunogenic capability. in laboratory trials, cert ...200214570129
control of ixodes scapularis and amblyomma americanum through use of the '4-poster' treatment device on deer in maryland.deer self-treatment devices ('4-posters') were evaluated for their efficacy in reducing populations of blacklegged ticks, ixodes scapularis, and lone star ticks, amblyomma americanum. at each of three locations in maryland, 25 '4-posters' were operated in study areas of approximately 5.18 km2. populations of host-seeking ticks were monitored by flagging of treated areas and similar untreated control areas without '4-posters.' from 1998 to 2002 the percent mortalities achieved were 69, 75.8 and 8 ...200214570143
prevalence of ectoparasites in a population of feral cats from north central florida during the summer.ectoparasites are a common and important cause of skin disorders in cats. ectoparasites are capable of disease transmission and can cause life-threatening anemia in young or debilitated animals. the objective of this study was to determine the potential feline ectoparasites in domestic cats by using a cohort of feral cats from north central florida that have not received veterinary care and have no known exposure to insecticide application. a total of 200 feral cats were randomly selected for th ...200212383632
hypersensitivity induced in dogs by nymphal extract of amblyomma cajennense ticks (acari:ixodidae).in general, hosts develop resistance to ticks after repeated infestations; nevertheless, several studies on naturally occurring host-tick interactions were unable to detect resistance of hosts to ticks even after repeated infestations. the purpose of this investigation was to study the type of cutaneous hypersensitivity to unfed nymphal extract of a. cajennense in dogs, which, unlike guinea pigs, do not develop resistance. a first, but no second, peak in skin reaction was observed, suggesting th ...200212381588
ticks associated with armadillo (euphractus sexcinctus) and anteater (myrmecophaga tridactyla) of emas national park, state of goias, brazil.this study was conducted in october 1998 and november 1999 in the emas national park (131,868 ha), a savanna-type cerrado region situated in the far south of goias state, brazil, near the geographic center of south america (15 degrees -23 degrees s; 45 degrees -55 degrees w). animals were captured with the aid of nets and anesthetized (15 mg/kg ketamine + 1 mg/kg xylasine) in order to collect ticks for identification and to establish laboratory colonies. they included giant anteaters (myrmecopha ...200212381607
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