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contributions to the knowledge of hard ticks (acari: ixodidae) in colombia.the known tick fauna of colombia includes 58 species (15 argasidae and 43 ixodidae). to add to the knowledge of the biology of ticks in colombia, hard ticks (ixodidae) were collected from domestic animals or vegetation during 2014-2016 in 10 of colombia's departments. ticks were identified to species through morphological examinations. taxonomic identification was confirmed for some specimens by molecular methods, including phylogenetic analyses inferred from three tick genes (cytochrome c oxida ...201829055642
life cycle and parasitic competence of dermacentor nitens neumann, 1897 (acari: ixodidae) on different animal species.the objective of this study was to evaluate the life cycle and parasitic competence of dermacentor nitens (neumann, 1897) on different animal species. experimental infestations were induced in five specimens each of seven species of possible hosts: rabbits, horses, sheep, cows, guinea pigs, birds and dogs. rabbits were infested in the ear using artificial feeding chambers, and the horses, sheep, cows and dogs were infested in the ear without feeding chambers. for the infestation of guinea pigs, ...201728063831
rhipicephalus microplus and dermacentor nitens (acari: ixodidae) coparasitize white-tailed deer on st. john, u.s. virgin islands.ticks parasitizing introduced white-tailed deer, odocoileus virginianus (zimmermann), on st. john, u.s. virgin islands, were recorded during and after drought conditions. tick infestation prevalences were 22% at the start of the drought (july 2015), 66% at the height of the drought (march 2016), and 35% after the drought had ended (july 2016; n = 67 deer). samples of ticks from 22 tranquilized deer in july 2016 revealed the presence of two species, the southern cattle tick, rhipicephalus (boophi ...201728591859
spotted fever: epidemiology and vector-rickettsia-host relationship in rio de janeiro state.the eco-epidemiological scenario of spotted fever (sf), a tick-borne disease that affects humans and other animals in several countries around the world, was analyzed in rio de janeiro (rj) state, brazil. during the last 34 years, 990 sf cases were reported in rj (the brazilian state with the highest population density), including 116 cases confirmed by serology (rifi) or pcr, among 42.39% of the municipalities with reported cases of sf. the epidemiologic dynamics of sf in rj state are very hete ...201728424664
molecular detection and identification of rickettsia species in ticks (acari: ixodidae) collected from belize, central america.little is known about tick-borne rickettsial pathogens in belize, central america. we tested ixodid ticks for the presence of rickettsia species in three of the six northern and western belizean districts. ticks were collected from domestic animals and tick drags over vegetation in 23 different villages in november 2014, february 2015, and may 2015. a total of 2,506 collected ticks were identified to the following species: dermacentor nitens neumann (46.69%), rhipicephalus sanguineus (latreille) ...201728981693
synanthropic mammals as potential hosts of tick-borne pathogens in panama.synanthropic wild mammals can be important hosts for many vector-borne zoonotic pathogens. the aim of this study was determine the exposure of synanthropic mammals to two types of tick-borne pathogens in panama, spotted fever group rickettsia (sfgr) and borrelia relapsing fever (rf) spirochetes. one hundred and thirty-one wild mammals were evaluated, including two gray foxes, two crab-eating foxes (from zoos), four coyotes, 62 opossum and 63 spiny rats captured close to rural towns. to evaluate ...201728060928
host specificity in a diverse neotropical tick community: an assessment using quantitative network analysis and host phylogeny.host specificity is a fundamental determinant of tick population and pathogen transmission dynamics, and therefore has important implications for human health. tick host specificity is expected to be particularly high in the tropics, where communities of ticks, hosts and pathogens are most diverse. yet the degree to which tropical tick species are host-specific remains poorly understood. combining new field data with published records, we assessed the specificity of tick-host associations in pan ...201627357506
ticks and rickettsiae from wildlife in belize, central america.the agents of spotted fevers in latin america are rickettsia rickettsii, r. parkeri, rickettsia sp. strain atlantic rainforest, and r. massiliae. in continental central america, r. rickettsii remains the only known pathogenic tick-borne rickettsia. in the present study, ticks were collected from wild mammals in natural areas of belize. besides providing new data of ticks from belize, we investigated rickettsial infection in some of these ticks. our results provide ticks harboring rickettsial age ...201626831147
growth of ehrlichia canis, the causative agent of canine monocytic ehrlichiosis, in vector and non-vector ixodid tick cell lines.canine monocytic ehrlichiosis is caused by ehrlichia canis, a small gram-negative coccoid bacterium that infects circulating monocytes. the disease is transmitted by the brown dog tick rhipicephalus sanguineus s.l. and is acknowledged as an important infectious disease of dogs and other members of the family canidae worldwide. e. canis is routinely cultured in vitro in the canine monocyte-macrophage cell line dh82 and in non-vector ixodes scapularis tick cell lines, but not in cells derived from ...201626837859
brazilian borreliosis with special emphasis on humans and horses.borreliosis caused by borrelia burgdorferi sensu lato is a cosmopolitan zoonosis studied worldwide; it is called lyme disease in many countries of the northern hemisphere and lyme-like or baggio-yoshinari syndrome in brazil. however, despite the increasing number of suspect cases, this disease is still neglected in brazil by the medical and veterinary communities. brazilian lyme-like borreliosis likely involves capybaras as reservoirs and amblyomma and rhipicephalus ticks as vectors. thus, domes ...201627769883
molecular ecological insights into neotropical bird-tick interactions.in the tropics, ticks parasitize many classes of vertebrate hosts. however, because many tropical tick species are only identifiable in the adult stage, and these adults usually parasitize mammals, most attention on the ecology of tick-host interactions has focused on mammalian hosts. in contrast, immature neotropical ticks are often found on wild birds, yet difficulties in identifying immatures hinder studies of birds' role in tropical tick ecology and tick-borne disease transmission. in panama ...201627203693
distribution of spotted fever group rickettsiae in hard ticks (ixodida: ixodidae) from panamanian urban and rural environments (2007-2013).tick-borne rickettsiosis is an important emerging disease in panama; to date, there have been 12 confirmed cases, including eight fatalities. to evaluate the distribution of rickettsiae in panamanian ticks, we collected questing and on-host ticks in urban and rural towns in elevations varying between 0 and 2300 m. a total of 63 sites (13 urban and 50 rural towns) were used to develop models of spatial distributions. we found the following tick species: rhipicephalus sanguineus s.l. (present in 5 ...201627068930
first molecular evidence of coxiella burnetii infecting ticks in cuba.coxiella burnetii is the causative agent of q fever. in order to explore the occurrence of c. burnetii in ticks, samples were collected from horses, dogs and humans living in a cuban occidental community. the species most commonly recovered were amblyomma mixtum (67%), rhipicephalus sanguineus s.l. (27%) and dermacentor nitens (6%). specific is1111 pcr and amplicon sequencing allowed the identification of c. burnetii dna in a. mixtum collected from a domestic horse. these findings, for first tim ...201626372520
detection of rickettsiae in fleas and ticks from areas of costa rica with history of spotted fever group rickettsioses.outbreaks of spotted fevers have been reported in costa rica since the 1950s, although vectors responsible for transmission to humans have not been directly identified. in this study, species of rickettsia were detected in ectoparasites from costa rica, mostly from five study sites where cases of spotted fevers have been reported. ticks and fleas were collected using drag cloths or directly from domestic and wild animals and pooled according to species, host, and location. pools were analyzed in ...201627592065
hard ticks (acari: ixodidae) of livestock in nicaragua, with notes about distribution.we document the species of ticks that parasitize livestock in nicaragua. the study was based on tick collection on cattle and horses from 437 farms in nine departments. of 4841 animals examined (4481 cows and 360 horses), 3299 were parasitized, which represent 68 % of the bovines and 67 % of the equines in study: 59 cows and 25 horses were parasitized by more than one species. in addition, 280 specimens of the entomological museum in león were examined. the ticks found on cattle were rhipicephal ...201627392740
acaricidal activity of methanol extract of acmella oleracea l. (asteraceae) and spilanthol on rhipicephalus microplus (acari: ixodidae) and dermacentor nitens (acari: ixodidae).we evaluated the acaricidal activity of acmella oleracea methanol extract and spilanthol on rhipicephalus microplus and dermacentor nitens. the extract was made through maceration with methanol. from this extract, a dichloromethane fraction with 99% spilanthol was obtained and tested on r. microplus larvae and engorged females and d. nitens larvae. for evaluation against larvae, the modified larval packet test was used, and both the methanol extract and dichloromethane fraction were tested at co ...201627692316
complete mitochondrial genomes of dermacentor silvarum and comparative analyses with another hard tick dermacentor nitens.ticks are obligate blood-sucking ectoparasites of a wide range of vertebrates. they can transmit a range of pathogens that cause economic losses to livestock production as well as human disease. in the present study, the complete mitochondrial (mt) genome of dermacentor silvarum was determined. the mt genome is 14,945 bp in length contains 37 genes, including 13 are protein-coding genes (cox1-3, nad1-6, nad4l, cytb, atp6 and atp8), two ribosomal rna genes and 22 transfer rna genes. the nucleotid ...201627423970
evaluation of the combined effect of thymol, carvacrol and (e)-cinnamaldehyde on amblyomma sculptum (acari: ixodidae) and dermacentor nitens (acari: ixodidae) larvae.this study aimed at assessing the combined effect of thymol, carvacrol and (e)-cinnamaldehyde on amblyomma sculptum and dermacentor nitens larvae. the effects resulting from treatments were evaluated by means of the modified larval packet test. in order to determine the lc50, components of essential oils, the monoterpenes thymol, carvacrol and phenylpropanoid (e)-cinnamaldehyde were individually tested at different concentrations. after determining the lc50, each essential oil component was sepa ...201526346899
native strains of beauveria bassiana for the control of rhipicephalus sanguineus sensu lato.rhipicephalus sanguineus sensu lato ticks are widespread worldwide due to their adaptability to survive under different environmental conditions. they may act as vectors of a wide range of pathogens to humans and animals and their control is based on the use of chemical products on dogs and in the environment. alternative control strategies, such as the use of entomopathogenic fungi as bio-control agents have also been investigated. the ability of native strains of beauveria bassiana sensu lato ...201525651851
molecular characterization of anaplasma marginale in ticks naturally feeding on buffaloes.anaplasma marginale is the most prevalent pathogen transmitted by ticks in cattle in tropical and subtropical regions of the world. however, the tick species involved in the transmission of a. marginale in buffaloes in brazil have not been identified. the objective of the present study was to determine the presence of a. marginale in ticks parasitizing water buffaloes. a total of 200 samples of rhipicephalus microplus, dermacentor nitens, amblyomma cajennense, and amblyomma maculatum were collec ...201526209411
molecular detection of theileria spp. in livestock on five caribbean islands.theileria spp. are tick-transmitted, intracellular apicomplexan protozoan parasites infecting a wide range of animals. as there is very limited information on the prevalence of theileria spp. in the caribbean we used the recently described genus-specific pan-theileria fret-qpcr to identify infected animals in the region and a standard 18s rrna gene pcr and sequencing to determine the species involved. we found theileria spp. in 9% of the convenience samples of animals (n = 752) studied from five ...201526783522
bacteria associated with amblyomma cajennense tick eggs.ticks represent a large group of pathogen vectors that blood feed on a diversity of hosts. in the americas, the ixodidae ticks amblyomma cajennense are responsible for severe impact on livestock and public health. in the present work, we present the isolation and molecular identification of a group of culturable bacteria associated with a. cajennense eggs from females sampled in distinct geographical sites in southeastern brazil. additional comparative analysis of the culturable bacteria from an ...201526537602
propagation of the israeli vaccine strain of anaplasma centrale in tick cell lines.anaplasma centrale has been used in cattle as a live blood vaccine against the more pathogenic anaplasma marginale for over 100 years. while a. marginale can be propagated in vitro in tick cell lines, facilitating studies on antigen production, immunisation and vector-pathogen interaction, to date there has been no in vitro culture system for a. centrale. in the present study, 25 cell lines derived from 13 ixodid tick species were inoculated with the israeli vaccine strain of a. centrale and mon ...201526210950
rickettsial infection in animals, humans and ticks in paulicéia, brazil.a previous study in paulicéia municipality, south-eastern brazil, reported 9.7% of the amblyomma triste ticks to be infected by rickettsia parkeri, a bacterial pathogen that causes spotted fever in humans. these a. triste ticks were shown to be associated with marsh areas, where the marsh deer blastocerus dichotomus is a primary host for this tick species. during 2008-2009, blood serum samples were collected from 140 horses, 41 dogs, 5 opossums (didelphis albiventris) and 26 humans in farms from ...201525643912
borrelia burgdorferi sensu lato in humans in a rural area of paraná state, brazil.this study describes the detection of borrelia garinii and borrelia burgdorferi sensu stricto (s.s.) in brazilian individuals using pcr and dna sequencing. our results suggest that these species are emerging pathogens in this country, and additional studies are necessary to determine the epidemiological characteristics of this disease in brazil.201526273276
tick-borne infections in human and animal population worldwide.the abundance and activity of ectoparasites and its hosts are affected by various abiotic factors, such as climate and other organisms (predators, pathogens and competitors) presenting thus multiples forms of association (obligate to facultative, permanent to intermittent and superficial to subcutaneous) developed during long co-evolving processes. ticks are ectoparasites widespread globally and its eco epidemiology are closely related to the environmental conditions. they are obligatory hematop ...201527047089
potentially novel ehrlichia species in horses, nicaragua.ehrlichia sp. dna was amplified from 4 ehrlichia-seroreactive horses from mérida, nicaragua. sequencing of 16s rdna, sodb, and groel genes indicated that the bacterium is most likely a novel ehrlichia species. the tick vector and the potential for canine and human infection remain unknown.201525625228
nhumirim virus, a novel flavivirus isolated from mosquitoes from the pantanal, brazil.we describe the isolation of a novel flavivirus, isolated from a pool of mosquitoes identified as culex (culex) chidesteri collected in 2010 in the pantanal region of west-central brazil. the virus is herein designated nhumirim virus (nhuv) after the name of the ranch from which the mosquito pool was collected. flavivirus rna was detected by real-time rt-pcr of homogenized mosquitoes and from the corresponding c6/36 culture supernatant. based on full-genome sequencing, the virus isolate was gene ...201425252815
first record of borrelia burgdorferi b31 strain in dermacentor nitens ticks in the northern region of parana (brazil).the aim of this study was to investigate the presence of dna of borrelia burgdorferi sensu lato (s.l.) in ticks that feed on horses used for animal traction in rural jataizinho, parana, brazil. between february and june 2008, a total of 224 ticks was collected of which 75% were identified as dermacentor nitens and 25% as amblyomma cajenense. to amplify b. burgdorferi s.l. dna, the intergenic space region (isr) between the 5s (rrf) 23s (rrl) rrna genes was used as targets for nested-pcr. two tick ...201424516456
the ticks (acari: ixodida: argasidae, ixodidae) of bolivia.the tick species reported in bolivia are reviewed here as (1) endemic or established: ornithodoros echimys, o. guaporensis, o. hasei, o. kohlsi, o. mimon, o. peropteryx, o. rostratus, otobius megnini, amblyomma auricularium, a. cajennense, a. calcaratum, a. coelebs, a. dubitatum, a. humerale, a. incisum, a. longirostre, a. naponense, a. nodosum, a. oblongoguttatum, a. ovale, a. parvitarsum, a. parvum, a. pecarium, a. pseudoconcolor, a. rotundatum, a. scalpturatum, a. tigrinum, a. triste, dermace ...201424406053
impact of humidity on clustered tick eggs.eclosion of larvae from clustered tick eggs (1, 5, 10, 15, 20, 25, 50, and ±1,000 eggs) of rhipicephalus sanguineus (rs), rhipicephalus microplus (rm), amblyomma cajennense (ac), and dermacentor nitens (dn) was investigated at 43, 75, and > 98% relative humidity (rh) and 25 °c. susceptibility of eggs to dehydration varied among tick species (rs < rm < ac and dn) and the number of clustered eggs but even singularized eggs of all tested species matured, and larvae eclosed at rh > 98%. a minimum of ...201425199556
seroprevalence of rickettsia spp. in equids and molecular detection of 'candidatus rickettsia amblyommii' in amblyomma cajennense sensu lato ticks from the pantanal region of mato grosso, brazil.the aim of the study was to evaluate exposure of equids to rickettsial agents (rickettsia rickettsii, rickettsia parkeri, 'candidatus rickettsia amblyommii', rickettsia rhipicephali, and rickettsia bellii) and rickettsial infection in ticks of a pantanal region of brazil. sera of 547 equids (500 horses and 47 donkeys) were evaluated by indirect immunofluorescence assay. in total, 665 adults and 106 nymphal pools of amblyomma cajennense f. sensu lato, 10 dermacentor nitens neumann ticks, and 88 l ...201426309313
use of plastic tips in artificial feeding of dermacentor (anocentor) nitens females neumann, 1897 (acari: ixodidae).the establishment of laboratory colonies of ticks is often hampered by their lack of adaptation to alternative hosts. the aim of this study was to artificially feed partially engorged dermacentor (anocentor) nitens females through plastic tips, and to identify what are the optimal conditions of application of this technique to get as much as possible close to the natural conditions. the technique of artificial feeding through plastic tips allowed the engorgement of d. nitens ticks to a final wei ...201425132536
repellent activity of eugenol on larvae of rhipicephalus microplus and dermacentor nitens (acari: ixodidae).the repellent activity of eugenol was evaluated on rhipicephalus microplus and dermacentor nitens larvae in a bioassay based on the vertical migration of these tick larvae during the host-seek phase. solutions were used at concentrations of 10, 20, 30, 40, and 50 μl/ml and a control only with the solvent ethanol 50 gl. the larvae's reaction of climbing the rods of filter paper was observed each hour for 12 h and once more at 24 h. the repellence was calculated as a percentage through visual esti ...201323636308
assessment of the acaricidal activity of carvacrol, (e)-cinnamaldehyde, trans-anethole, and linalool on larvae of rhipicephalus microplus and dermacentor nitens (acari: ixodidae).the acaricidal activity of carvacrol, (e)-cinnamaldehyde, trans-anethole, and linalool was studied on rhipicephalus microplus and dermacentor nitens larvae. all the substances were tested at concentrations of 2.5, 5.0, 10.0, 15.0, and 20.0 μl/ml, with 10 repetitions per treatment. the modified larval packet technique was employed in the tests and the mortality was evaluated after 24 h. in the groups treated with carvacrol, the lowest concentration (2.5 μl/ml) was sufficient to cause 100% death o ...201323354938
environmentally associated ticks (acari: ixodidae) in campo grande, mato grosso do sul, brazil.herein, we report tick species found on wild and domestic animals and in the environment during a one-year sampling period at the brazilian farming research company beef cattle unit (embrapa beef cattle), which is located within the urban area of campo grande, mato grosso do sul, brazil. from 55 wild hosts including six different species (nasua nasua, cebus spp., cerdocyon thous, myrmecophaga tridactyla, tamandua tetradactyla and dasyprocta aguti), 323 ticks were collected. amblyomma ovale ticks ...201324252958
ticks on birds in a savanna (cerrado) reserve on the outskirts of uberlândia, minas gerais, brazil.we report tick infestations on birds, in the environment and on domestic animals in a non-forested phytophysiognomy, the savanna-like cerrado sensu stricto, in a natural reserve on the outskirts of the urban area of uberlândia, minas gerais, brazil. overall, 238 birds within 50 species, 15 families and six orders were caught. passeriformes were the most numerous, with 216 birds (90.75%), among which 22 had ticks (n = 31). within this order, the prevalence of tick infestation was 10.2%, and the a ...201323471429
serum antibodies from a subset of horses positive for babesia caballi by competitive enzyme-linked immunosorbent assay demonstrate a protein recognition pattern that is not consistent with infection.tick-borne pathogens that cause persistent infection are of major concern to the livestock industry because of transmission risk from persistently infected animals and the potential economic losses they pose. the recent reemergence of theileria equi in the united states prompted a widespread national survey resulting in identification of limited distribution of equine piroplasmosis (ep) in the u.s. horse population. this program identified babesia caballi-seropositive horses using rhoptry-associ ...201324049108
detection of rickettsia parkeri from within piura, peru, and the first reported presence of candidatus rickettsia andeanae in the tick rhipicephalus sanguineus.domestic farm animals (n=145) were sampled for the presence of ectoparasites in northwestern peru during march, 2008. ninety domestic animals (62%) were positive for the presence of an ectoparasite(s) and produced a total collection of the following: 728 ticks [amblyomma maculatum, anocentor nitens, rhipicephalus (boophilus) microplus, rhipicephalus sanguineus, and otobius megnini], 12 lice (haematopinus suis), and 3 fleas (ctenocephalides felis). a rickettsia genus-specific qpcr assay was perfo ...201323488453
chemical composition and insecticidal activity of plant essential oils from benin against anopheles gambiae (giles).insecticide resistance in sub-saharan africa and especially in benin is a major public health issue hindering the control of the malaria vectors. each anopheles species has developed a resistance to one or several classes of the insecticides currently in use in the field. therefore, it is urgent to find alternative compounds to conquer the vector. in this study, the efficacies of essential oils of nine plant species, which are traditionally used to avoid mosquito bites in benin, were investigate ...201324298981
molecular epidemiology of theileria equi in horses and their association with possible tick vectors in the state of rio de janeiro, brazil.the aim of this study was to detect theileria equi (laveran 1901) dna in horses and ticks using real-time pcr and to list the factors associated with infection in animals located in the seropedica and petropolis municipalities of the state of rio de janeiro. we tested blood samples from 314 horses and samples from 300 ticks, including 191 amblyomma cajennense, 104 dermacentor nitens, and 5 ixodida larvae. factors inherent to the horse, the ownership, and animal management were obtained from an e ...201323474658
comparative genomic analysis and phylogenetic position of theileria equi.transmission of arthropod-borne apicomplexan parasites that cause disease and result in death or persistent infection represents a major challenge to global human and animal health. first described in 1901 as piroplasma equi, this re-emergent apicomplexan parasite was renamed babesia equi and subsequently theileria equi, reflecting an uncertain taxonomy. understanding mechanisms by which apicomplexan parasites evade immune or chemotherapeutic elimination is required for development of effective ...201223137308
effect of attractant sex pheromone on immature larval stages of ixodid tick species.attractant sex pheromone (asp) 2,6-dichloro phenol was used in the current study to evaluate the percentage attraction and the behavioural responses of the five ixodid tick species namely rhipicephalus sanguineus, rhipicephalus microplus (boophilus microplus), haemaphysalis bispinosa, rhipicephalus haemaphysaloides and hyalomma marginatum using petridish bioassay. two concentrations of 2,6-dcp (0.1 m and 0.05 m) was used for the larval stages of all five ixodid tick species of which 0.1 m concen ...201224082519
[detection of rickettsia in ectoparasites of wild and domestic mammals from the cerro chucanti private reserve and from neighboring towns, panamá, 2007-2010].ectoparasites are the main vectors of rickettsiosis. in panama, however, limited data are available concerning the arthropod species that serve as vectors or reservoirs.201223242292
toxicity of solvents and surfactants to amblyomma cajennense (fabricius, 1787) (acari: ixodidae) and dermacentor nitens (neumann, 1897) (acari: ixodidae) larvae.the objective of this work was to verify the sensitivity of amblyomma cajennense and dermacentor nitens larvae to the solvents ethanol, methanol, acetone, xylol and dimethyl sulfoxide (dmso) and the surfactant tween 80. the first four solvents were tested at analytical purity while the dmso and surfactant tween 80 were tested at a concentration of 1%. the substances tested at analytical purity that caused high mortality were also tested at concentrations of 50%, 25% and 1%. the larval packet tes ...201222459626
chemical composition and acaricidal activity of essential oil from lippia sidoides on larvae of dermacentor nitens (acari: ixodidae) and larvae and engorged females of rhipicephalus microplus (acari: ixodidae).the aim of this work was to identify the compounds and to investigate the acaricidal activity of the essential oil from the leaves of lippia sidoides on rhipicephalus microplus and dermacentor nitens. the oil was obtained by hydrodistillation and analyzed by gas chromatography (gc/fid) and gas chromatography/mass spectrometry. in total, 15 compounds comprising 99.97 % of the total peak area were identified. the main constituent of the essential oil was thymol (67.60 %). the acaricidal activity w ...201222983219
acaricidal activity of eugenol on rhipicephalus microplus (acari: ixodidae) and dermacentor nitens (acari: ixodidae) larvae.the aim of this study was to evaluate the acaricidal activity of eugenol, with different solubilizations and concentrations, on rhipicephalus microplus and dermacentor nitens larvae and to determine the lethal time. the study consisted of four experiments, and the mortality was assessed using the larval packet test with adaptations. the mortality observed in the first experiment was 100 % for all the groups treated with eugenol solubilized in different solvents. in the second, the hydroethanolic ...201222622689
association between ecological factors and the presence of rhipicephalus (boophilus) microplus larvae in puerto rico.a prevalence study was conducted to survey tick larvae populations in puerto rico (pr), compare the number of infested sites with rhipicephalus (boophilus) microplus larvae between the wet and dry season, and assess the associations of ecologic factors on the presence of r. microplus larvae. ninety-six sites were selected using a gis-based sampling method. each site was sampled twice; the first sampling was performed during the dry season (march 4-18, 2007) and the second sampling during the wet ...201222638941
infection by spotted fever rickettsiae in people, dogs, horses and ticks in londrina, parana state, brazil.spotted fever is a disease caused by bacteria from the genus rickettsia of the spotted fever group (sfg). rickettsia rickettsii is likely the main agent of brazilian spotted fever (bsf). with the objective of gathering information on the circulation of sfg rickettsiae in londrina, parana state, ticks from dogs and horses and also blood from dogs, horses and humans were collected in a neighbourhood of the city which presented potential for circulation of rickettsiae between hosts and vectors. amb ...201121824336
association of different genetic types of francisella-like organisms with the rocky mountain wood tick (dermacentor andersoni) and the american dog tick (dermacentor variabilis) from localities near their northern distributional limits.dermacentor andersoni and dermacentor variabilis from allopatric and sympatric populations near their northern distributional limits were examined for the presence of francisella species using molecular techniques that targeted 373 bp of the 16s ribosomal rna gene. although there was no evidence for the presence of francisella tularensis in any tick, francisella-like endosymbionts (fles) were common in d. andersoni and d. variabilis adults and immatures. a significantly greater proportion of fem ...201122179251
tick cell lines for study of crimean-congo hemorrhagic fever virus and other arboviruses.abstract continuous cell lines derived from many of the vectors of tick-borne arboviruses of medical and veterinary importance are now available. their role as tools in arbovirus research to date is reviewed and their potential application in studies of tick cell responses to virus infection is explored, by comparison with recent progress in understanding mosquito immunity to arbovirus infection. a preliminary study of propagation of the human pathogen crimean-congo hemorrhagic fever virus (cc ...201121955214
acaricidal activity of hydroethanolic formulations of thymol against rhipicephalus sanguineus (acari: ixodidae) and dermacentor nitens (acari: ixodidae) larvae.the aim of this study was to assess the acaricidal activity of hydroethanolic formulations of thymol at varying concentrations on rhipicephalus sanguineus and dermacentor nitens larvae. the larval packet test was used and the thymol concentrations tested were 2.5, 5.0, 10.0, 15.0 and 20.0mg/ml. the control group was exposed only to water and ethanol (50/50%) and there were 10 repetitions for each treatment. the mortality was evaluated after 24h. for the r. sanguineus larvae, the mortality rates ...201122137349
factors associated to theileria equi in equids of two microregions from rio de janeiro, brazil.serum samples from 714 equids of itaguaí and serrana microregions, rio de janeiro, southeastern brazil, were examined by indirect fluorescent antibody test (titer 1:80) for theileria equi. the prevalence in the microregions and factors associated with seropositivity were evaluated and the prevalence ratio (pr) calculated. the overall prevalence of t. equi infection was 81.09% (n = 579), with higher prevalence (p < 0.05) in the itaguaí (85.43%) when compared to serrana microregion (76.92%). the g ...201121961755
molecular detection of bartonella species in ticks from peru.a total of 103 ticks, collected from canines, horses, donkeys, and snakes from peru, were screened for the presence of bartonella dna by polymerase chain reaction analysis. bartonella dna was detected in two ticks using bartonella 16s-23s intergenic spacer region primers and in an additional two ticks using bartonella nadh dehydrogenase gamma subunit gene (nuog) primers. bartonella rochalimae eremeeva et al., b. quintana schmincke, and b. elizabethae daly et al. dna was detected in a rhipicephal ...201122238888
spotted fever group rickettsia infecting ticks (acari: ixodidae) in the state of santa catarina, brazil.during 2006-2008, a total of 260 adult ticks were collected from domestic and wild animals in different regions of the state of santa catarina (sc), brazil, including areas where human cases of brazilian spotted fever have been reported. collected ticks belonging to nine species (amblyomma aureolatum, amblyomma cajennense, amblyomma dubitatum, amblyomma longirostre, amblyomma ovale, amblyomma tigrinum, dermacentor nitens, rhipicephalus microplus and rhipicephalus sanguineus) were tested by polym ...201122241112
ticks (acari: ixodidae) within various phytophysiognomies of a cerrado reserve in uberlândia, minas gerais, brazil.cerrado biome, the south american savannah, covers about 2 million km(2) and is very rich in endemic species but threatened by agriculture. in this report free-living tick species are presented, and their seasonal and relative distribution within the various phytophysiognomies in a small cerrado reserve in minas gerais state, brazil. overall 2,694 free-living ticks were found during a 2 years sampling period with co(2) traps and cloth dragging. of these, 73.5% were amblyomma cajennense and 0.6% ...201019693680
acaricidal activity of the essential oils from eucalyptus citriodora and cymbopogon nardus on larvae of amblyomma cajennense (acari: ixodidae) and anocentor nitens (acari: ixodidae).the present study evaluated the acaricidal activity of essential oils from eucalyptus citriodora and cymbopogon nardus on non-engorged larvae of amblyomma cajennense and anocentor nitens. in order to carry out the study, six groups were formed, each concentration being a treatment (6.25%, 12.5%, 25%, and 50%, respectively) and also with the creation of a control group (distilled water) and a positive control (deltametrine). for each treatment, approximately 100 larvae of these ticks were placed ...201020640444
occurrence of ticks (acari: ixodidae) on human hosts, in three municipalities in the state of pará, brazil.assuming the existence of tick parasitism in humans in the state of pará, an aggregate observational study was developed along a transversal line in three cities of the state, during two years. interviews and examinations of 2,160 townspeople and tourists were carried out, without discrimination of ethnic, sex, age, or social status, and classified for effects analyzed for four bands of age, six types of activities in the society, and two sexes. larvae, nymphs, and adults of ticks had been ident ...201020943016
rickettsia in synanthropic and domestic animals and their hosts from two areas of low endemicity for brazilian spotted fever in the eastern region of minas gerais, brazil.the aim of this study was to understand the current epidemiology of rickettsial diseases in two rickettsial-endemic regions in brazil. in the municipalities of pingo d'agua and santa cruz do escalvado, among serum samples obtained from horses and dogs, reactivity by immunofluorescent assay against spotted fever group rickettsiae was verified. in some serum samples from opossums (didelphis aurita) captured in santa cruz do escalvado, serologic response against rickettsiae was also verified. polym ...201021118939
rickettsial infection in domestic mammals and their ectoparasites in el valle de antón, coclé, panamá.the present research evaluated the presence of rickettsia spp. on ectoparasites of horses and dogs (using pcr techniques), and their sera (using immunofluorescence assay) in el valle de antón town in panama. a total of 20 horses and 20 dogs were sampled, finding four species of ectoparasites on dogs (the ticks rhipicephalus sanguineus, amblyomma ovale, amblyomma oblongoguttatum, and the flea ctenocephalides felis), and two tick species on horses (amblyomma cajennense and dermacentor nitens). dna ...201021144663
detection of theileria and babesia in brown brocket deer (mazama gouazoubira) and marsh deer (blastocerus dichotomus) in the state of minas gerais, brazil.intraerythrocytic protozoan species of the genera theileria and babesia are known to infect both wild and domestic animals, and both are transmitted by hard-ticks of the family ixodidae. the prevalences of hemoprotozoa and ectoparasites in 15 free-living mazama gouazoubira, two captive m. gouazoubira and four captive blastocerus dichotomus from the state of minas gerais, brazil, have been determined through the examination of blood smears and the use of nested polymerase chain reaction (npcr). t ...201021354704
structural study of the salivary glands of anocentor nitens (acari: ixodidae) during the feeding cycle.the salivary glands of anocentor nitens (neumann,1897) occur in pairs and are located in the anterolateral region of the general cavity, with milky white color and approximately equal sizes. they consist of a secretory portion and an excretion duct. in some glandular acini, all the cells had a basophilic appearance they were stained by hematoxylin, whereas others presented cells with different staining affinities. in this work, we describe the variations observed in these glands during the feedi ...201019544533
[occurrence of ticks (acari: ixodidae) in the municipality of goiatins, tocantins].due to a suspected human case of brazilian lyme-like disease in the city of goiatins, tocantins state, an epidemiological survey was carried out in eight counties in this region during september 2007 and february 2008, where 1,890 ticks were collected from domestic animals and from the environment. a total of eight tick species were identified: rhipicephalus sanguineus, rhipicephalus (boophilus) microplus, dermacentor nitens, amblyomma cajennense, amblyomma oblongoguttatum, amblyomma ovale, ambl ...200919602318
imidocarb dipropionate clears persistent babesia caballi infection with elimination of transmission potential.antimicrobial treatment of persistent infection to eliminate transmission risk represents a specific challenge requiring compelling evidence of complete pathogen clearance. the limited repertoire of antimicrobial agents targeted at protozoal parasites magnifies this challenge. using babesia caballi as both a model and a specific apicomplexan pathogen for which evidence of the elimination of transmission risk is required for international animal movement, we tested whether a high-dose regimen of ...200919620328
detection and identification of rickettsial agents in ticks from domestic mammals in eastern panama.several outbreaks of rocky mountain spotted fever have occurred in recent years in colombian communities close to the border with panama. however, little is known about rickettsiae and rickettsial diseases in eastern panamanian provinces, the darien province and the kuna yala, located north of the endemic area in colombia. in 2007, 289 ticks were collected in several towns from dogs, horses, mules, cows, and pigs. dna was extracted from 124 dermacentor nitens, 64 rhipicephalus sanguineus, 43 amb ...200919645289
ticks on domestic animals in pernambuco, northeastern brazil.the objective of this article was to discuss some aspects of ticks associated with domestic animals in the state of pernambuco, northeastern brazil, based on a literature review and present new data obtained from recent tick collections carried out in this northeastern brazilian state. from august 2007 to june 2008, 1,405 ticks were collected and five species were identified: amblyomma cajennense (fabricius, 1787), amblyomma ovale koch, 1844, dermacentor nitens neumann, 1897, rhipicephalus (boop ...200919772771
surveys for ectoparasites on wildlife associated with amblyomma variegatum (acari: ixodidae)-infested livestock in st. croix, u.s. virgin islands.surveys in 2001, 2005, and 2006 attempted to determine the role of wildlife in maintenance and dissemination of the tropical bont tick, amblyomma variegatum (f.) (acari: ixodidae), in st. croix, u.s. virgin islands. small mammals; birds; white-tailed deer, odocoileus virginianus (zimmermann); and feral cattle, bos taurus l., were examined at nine premises, in mountainous rain forest, and in surrounding areas in western st. croix, an area including and central to all known bont tick-infested prem ...200919960701
prevalence of equine piroplasmosis and its association with tick infestation in the state of são paulo, brazil.serum samples were collected from 582 horses from 40 stud farms in the state of são paulo and tick (acari: ixodidae) infestations were evaluated on them. serum samples were subjected to the complement fixation test (cft) and a competitive inhibition elisa (celisa) for babesia caballi and theileria equi. logistic regression analyses were performed to construct multivariate models that could explain the dependent variable (horses positive for b. caballi or t. equi) as a function of the independent ...200920040201
evaluation of the efficacy of strains of steinernema carpocapsae santa rosa and all (steinernematidae: rhabditida) to control engorged female anocentor nitens (acari: ixodidae).in view of the need to combat the generalized spread of resistance in ticks to commercial acaricides, the objective of this study was to evaluate the action of entomopathogenic nematodes (steinernema carpocapsae, strains santa rosa and all) on engorged female anocentor nitens. five ticks per petri dish were exposed to concentrations of 500, 5,000, or 25,000 infective juveniles of s. carpocapsae for 72 h. after transferring the ticks to clean plates, biological parameters were analyzed. related t ...200919123009
francisella-like endosymbiont dna and francisella tularensis virulence-related genes in brazilian ticks (acari: ixodidae).ticks are vectors of a variety of pathogens, including francisella tularensis. bacteria in the genus francisella have been identified mostly in the northern hemisphere and include tick endosymbionts. francisella has never been described in brazil, where amblyomma spp. ticks are known as the vector of many bacterial zoonotic pathogens. in the present work, we have identified bacterial dna sequences with identity to francisella genes in amblyomma dubitatum neumann dermacentor nitens (neumann), and ...200919351090
[artificial feeding through capillaries tubes of engorged partially females of the tick dermacentor (anocentor) nitens].artificial feeding is an important toll for studying ticks feeding mechanism and transmission of pathogenic agents in the absence of vertebrate host. the objective was to feed artificially of engorged partially females of dermacentor (anocentor) nitens, proceeding of infested naturally equines and evaluate the influence of this technique on biological parameters of species. engorged partially females were collected, weighted and separate by weight in two range of 40 to 60 milligrams and 61 to 10 ...200820059812
[control of anocentor nitens (neumann, 1897) (acari: ixodidae) on equines].this trial evaluated control practices of anocentor nitens on equines, using spraying devices and application of acaricide paste formulation in the auricular pavilion and nasal diverticulum. the study was carried out from october 2003 to march of 2008 and the evaluations had been divided in the following stages: phase 1--out/03 mar/04 and phases 2, 3, 4 and 5, respectively, correspondents to the month's periods until março/08. it was used score of 0 to 3 to classify infestation levels. from abr/ ...200820059817
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
transmission of babesia caballi by dermacentor nitens (acari: ixodidae) is restricted to one generation in the absence of alimentary reinfection on a susceptible equine host.the tropical horse tick, dermacentor nitens, is a natural vector of babesia caballi in the americas. b. caballi, one of the etiologic agents of equine piroplasmosis, occurs widely throughout the world, but the united states and a few other countries are considered to be free of infection. b. caballi is transovarially transmitted by the one-host tick d. nitens; we tested the hypothesis that b. caballi can persist in multiple generations of d. nitens in the absence of opportunity to reacquire infe ...200819058641
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
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
efficacy of 2,6-dichlorophenol lure to control dermacentor nitens.this study was carried out with the objective of evaluating the efficacy of a 2,6-dichlorophenol (2,6-dcp) lure to control dermacentor nitens (acari: ixodidae). slow-release formulations of the pheromone formulated with and without cypermethrin were prepared. olfactometer bioassays were used to define the best dose of the pheromone and to evaluate the effect of cypermethrin with 2,6-dcp attractiveness. sexually active males were released 15 cm from 2 cmx1 cm pieces of polypropylene treated with ...200717459588
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
rocky mountain spotted fever, colombia.we investigated 2 fatal cases of rocky mountain spotted fever that occurred in 2003 and 2004 near the same locality in colombia where the disease was first reported in the 1930s. a retrospective serosurvey of febrile patients showed that > 21% of the serum samples had antibodies aaainst spotted fever group rickettsiae.200718214179
[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
natural co-infection of babesia caballi and encephalitozoon-like microsporidia in the tick anocentor nitens (acari: ixodidae).the present paper reports the occurrence of natural co-infection of babesia caballi and encephalitozoon-like microsporidia in the tick anocentor nitens. engorged females of ticks, collected from a naturally b. caballi-infected horse, were incubated at 27 degrees c and relative humidity over 83%. after a 6-day incubation period, giemsa-stained smears prepared from hemolymph were examined microscopically under oil immersion. b. caballi infected ticks were dissected and samples of midgut tissue wer ...200616973173
[study of foveae dorsales of nymphs and adults of four species of ticks (acari: ixodidae) by scanning electron microscopy].the foveae dorsalis, the external opening of the sex pheromone 2,6-dichlorophenol producer gland, of amblyomma cajennense, dermacentor nitens, rhipicephalus (boophilus) microplus and rhipicephalus sanguineus was studied with scanning electron microscopy. at least three specimens from each stage: unfed larvae, nymphs, females and males, and females fed for 4 to 6 days were examined. the foveae dorsales were not observed in larvae and r. (b.) microplus males. the foveae dorsales were observed as p ...200616978471
rhythm of engorgement and detachment of anocentor nitens females feeding on horses.the present study evaluated the engorgement and drop-off rhythms of anocentor nitens females feeding on horses. drop-off rhythm was evaluated at 6h-intervals (06:00, 12:00, 18:00, and 00:00 h) on horses held in stalls or in a pasture. a new method of marking feeding female ticks (the bowknot technique) was developed to evaluate ticks on horses in pasture that attached to different parts of the horse's body. this technique was highly successful, indicating no significant interference on tick engo ...200616481114
[parasites of the central american tapir tapirus bairdii (perissodactyla: tapiridae) in chiapas, mexico].we analyzed 19 samples of baird's tapir feces from la sepultura biosphere reserve, collected between march and july 1999. we also took samples directly from a male tapir captured at the montes azules biosphere reserve. both reserves are in chiapas, mexico. we used five techniques: flotation, macmaster, micrometric, ritchie's sedimentation and ferreira's quantitative. in addition, we collected ectoparasites from animals captured in both reserves and from a captive couple from tuxtla gutierrez, ch ...200618494314
rickettsial infection in animals and brazilian spotted fever endemicity.we compared the rickettsial infection status of amblyomma cajennense ticks, humans, dogs, and horses in both brazilian spotted fever (bsf)-endemic and -nonendemic areas in the state of sao paulo, brazil. most of the horses and few dogs from bsf-endemic areas had serologic titers against rickettsia rickettsii antigens. in contrast, no dogs or horses from bsf-nonendemic areas had serologic titers against r. rickettsii antigens, although they were continually exposed to a. cajennense ticks. all hum ...200515752445
ticks and tick-borne disease in guatemalan cattle and horses.blood samples and ticks were collected from 48 cattle and 74 horses from seven sites in the peten region of guatemala. data on body condition, mucous membrane capillary refill time and tick infestation levels were recorded for each animal in the study. horses had significantly higher levels of tick infestation than cattle, as well as poorer body condition scores. seroprevalence of babesia spp. was 95.8% for b. bovis in cattle, 89.6% for b. bigemina in cattle, and 92.7% for b. equi in horses. ser ...200515936147
quantification of sex pheromone from anocentor nitens by gas chromatography-mass spectrometry-selected ion monitoring.two highly sensitive and selective methods based on gas chromatography coupled to mass spectrometry (gc-ms) in the selected ion monitoring (sim) mode have been developed for the quantification of 2,6-dichlorophenol (2,6-dcp), a sex pheromone of the tick females of anocentor nitens. standard addition method and calibration curve techniques using 5-bromine-4-hydroxy-3-methoxybenzaldehyde (5-brv) as internal standard (is) afforded detection limit of 0.1ngml(-1). the calibration curve was linear ove ...200418969341
phylogenetic analysis of the francisella-like endosymbionts of dermacentor ticks.bacterial endosymbionts with significant homology to francisella tularensis (gamma-proteobacteria) have been described from at least five species of ticks in three different genera, including two north american dermacentor species [d. andersoni stiles and d. variabilis (say)]. the evolutionary relationships among the francisella-like endosymbionts (fle) from different hosts and between fle and the arthropod-borne pathogen f. tularensis are not known. a 1,169-base fragment of the 16s rdna and a 7 ...200415185926
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
horse resistance to natural infestations of anocentor nitens and amblyomma cajennense (acari: ixodidae).the objective of this study was to investigate some aspects of horse resistance to natural infestations of anocentor nitens and amblyomma cajennense over a 2-year period. free-living stages of a. nitens were used to evaluate the influence of season of the year on horse resistance. every 2 weeks, 10 selected engorged females, weighing 150-329 mg, were removed from naturally infested horses and were individually placed into glass tubes closed with a cotton stopper, and maintained in an incubator. ...200211812624
seasonal dynamics of ticks (acari: ixodidae) on horses in the state of são paulo, brazil.natural tick infestations were assessed every 14 days on horses over a 2-year period. amblyomma cajennense adult ticks were counted individually, without detachment from the horses. larvae and nymphs of a. cajennense were collected using a rubber scraper that scratched engorged immature ticks from the host. adult females of anocentor nitens larger than 4mm length were counted on the horses. blood samples were also obtained from the horses every 14 days and macroclimatic data were obtained for th ...200211879967
the role of 2,6-dichlorophenol as sex pheromone of the tropical horse tick anocentor nitens (acari: ixodidae).the objective of this study was to evaluate the role of 2,6-dichlorophenol (2,6-dcp) as sex pheromone of anocentor nitens. sex pheromones were extracted by submerging 150 female fed for 6 days in hexane (3 ml) for two hours and sonicating them for 15 min. the extract was analyzed by gc-ms employing the single ion monitoring (sim) method. identification of 2,6-dcp was based on the comparison of mass spectra with a computer search using the nist library and by matching the mass spectrum of the pea ...200212593587
risk factors to tick infestations and their occurrence on horses in the state of são paulo, brazil.from december 1998 to march 1999, 40 stud farms were studied in the state of são paulo, brazil. during visits to farms, horses reared under grazing conditions were examined for the presence of ticks. on each farm visit, horse pastures were closely inspected and a questionnaire was given to the farm supervisor with the purpose of gaining information about ecological and management variables (independent variables) that could be associated with the presence and infestation levels of ticks on the f ...200111337122
seasonal analysis of the number of aeropiles in anocentor nitens (neumann, 1897) (acari: ixodidae) from the state of rio de janeiro, brazil.variation between aeropile numbers of the right and left peritrematic plate in male and female anocentor nitens (neumann, 1897) is reported from a site in brazil. from january to december 1998, 146 males and 247 females of a. nitens were recovered from equus caballus l. in silva jardim district, state of rio de janeiro. asymmetry of numbers of aeropiles between right and left plates occurred in 83.6% of the males and 82.2% of the females. differences in the number of aeropiles between the sexes ...200111500781
seasonal dynamics of anocentor nitens on horses in brazil.anocentor nitens is a widespread ectoparasite of horses in brazil. a study of the seasonal dynamics of the parasitic phase of this tick was made by regular census of engorging females (>/=4mm) on free-ranging horses, fortnightly from july 1995 to july 1997, at pedro leopoldo, minas gerais. twenty horses were divided into four groups of five animals per group, each having a similar mix of resistant and less resistant animals, based on initial infestation. every 2 weeks, one of the groups, in sequ ...200010760407
a review of the ticks (acari, ixodida) of brazil, their hosts and geographic distribution - 1. the state of rio grande do sul, southern brazil.a review of the ticks (acari, ixodida) of the state of rio grande do sul, southern brazil, was completed as a step towards a definitive list (currently indicated as 12) of such species, their hosts and distribution. the ticks: argas miniatus (poultry), ixodes loricatus (opossums), amblyomma aureolatum (dogs), a. calcaratum (anteaters), a. cooperi (capybaras), a. nodosum (anteaters), a. tigrinum (dogs) (neotropical) and rhipicephalus sanguineus (dogs) (introduced, cosmopolitan, afrotropical) were ...200010904399
thermal constant estimation in tropical horse tick, anocentor nitens (acari:ixodidae).experience has demonstrated that the exclusive use of acaricides as a control method against cattle ticks causes several problems, and is not totally effective. other methods need to be added in order to achieve better and more profitable control of these parasites. groups of 12 to 15 engorged ticks, bred on bovines, were individually incubated at six temperatures (t = 24, 26, 28, 30, 32, and 34 degrees c) and four relatives humidities (rh = 100, 80, 75.5, and 70%), creating 24 variants. the ons ...200011193636
larval survival of anocentor nitens under simulated natural conditions.basic knowledge about the survival of free living stages of ticks is of great importance as a practical tool to improve control methods. for anocentor nitens there is little information on this subject. eighty-four engorged females were incubated at 30 degrees c and 100% relative humidity. after 17 days, groups of 5,500 eggs each were collected and isolated in vials. age zero was defined as 10 days after eclosion had begun. at this time vials with larvae were attached to 40 sorghum halepense pla ...200011193638
report on ticks collected in the southeast and mid-west regions of brazil: analyzing the potential transmission of tick-borne pathogens to man.specimens of ticks were collected in 1993, 1996, 1997, and 1998, mostly from wild and domestic animals in the southeast and mid-west regions of brazil. nine species of amblyommidae were identified: anocentor nitens, amblyomma cajennense, amblyomma ovale, amblyomma fulvum, amblyomma striatum, amblyomma rotundatum, boophilus microplus, boophilus annulatus, and rhipicephalus sanguineus. the potential of these tick species as transmitters of pathogens to man was analyzed. a flaviviridade flavivirus ...199910881097
presence of sex pheromones in anocentor nitens (acari: ixodidae).the aim of this study was to investigate whether there are sex pheromones in the tropical horse tick, anocentor nitens (neumann). when virgin males and females, fed on rabbits for 3-7 d, were tested reciprocally, there was a direct correlation between attractiveness and the period of feeding; attraction was greater (and with the fastest responses) in males and females fed for at least 6 d (sexually active males and confirmed attractive females). the capacity of sexually active males to orient to ...199910071492
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