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phylogeny, evolution and historical zoogeography of ticks: a review of recent progress.there has been much progress in our understanding of the phylogeny and evolution of ticks, particularly hard ticks, in the past 5 years. indeed, a consensus about the phylogeny of the hard ticks has emerged. our current working hypothesis for the phylogeny of ticks is quite different to the working hypothesis of 5 years ago. so that the classification reflects our knowledge of ticks, several changes to the nomenclature of ticks are imminent. one subfamily, the hyalomminae, will probably be sunk, ...200214570116
ticks and tick-borne diseases of livestock belonging to resource-poor farmers in the eastern free state of south africa.the paper provides a summary of three studies conducted in the eastern free state of south africa between 1998 and 2000. in a questionnaire-based study approximately 21% of interviewed resource-poor farmers (n = 150) indicated that they experienced problems with ticks and tick-borne diseases. about 56% of farmers indicated that tick-related problems were most severe in summer, while 32% indicated that the most problems were encountered in winter. about 12% indicated that the tick problems were e ...200214570134
in vitro detection of acaricide resistance in boophilus microplus (acari: ixodidae).the cattle tick boophilus microplus causes significant economic losses in cattle in the tropical areas of central and south america. acaricides are widely used to control tick infestations, with the consequent selection of tolerant and resistant subpopulations. detoxifying enzymes, and esterases in particular, have been associated with organophosphate resistance in mexican isolates of b. microplus ticks. here, we present results of the biochemical detection of esterases and oxidases in 20 isolat ...200214570140
abstracts of the fourth international symposium on molecular insect science. may 28-june 2, 2002. tucson, arizona, usa. 200215455051
molecular and biochemical diagnosis of esterase-mediated pyrethroid resistance in a mexican strain of boophilus microplus (acari: ixodidae).we examined pyrethroid resistant mexican strains of boophilus microplus using biochemical and molecular tests to determine the mechanisms conferring resistance. permethrin hydrolysis assays and esterase activity gels indicated enhanced esterase-mediated metabolic detoxification in the cz strain, while one other pyrethroid resistant strain, sf, and two pyrethroid susceptible strains had lower levels of permethrin hydrolysis. results from assays using a pcr-based test to detect a pyrethroid target ...200214570139
comparative inhibition kinetics for acetylcholinesterases extracted from organophosphate resistant and susceptible strains of boophilus microplus (acari: ixodidae).in this study, acetylcholinesterases (aches) were extracted from two mexican boophilus microplus strains that demonstrated resistance to the organophosphate (op) acaricide, coumaphos, in bioassay. the rate of inhibition of the extracted aches by the diethyl-op paraoxon was determined for two resistant strains and two susceptible strains of b. microplus. the time to inhibition of 50% ache activity was approximately two-fold greater for the resistant strains. kinetic analysis of the interaction of ...200212539837
isolation and identification of an esterase from a mexican strain of boophilus microplus (acari: ixodidae).a strain of mexican boophilus microplus (cz) collected near coatzacoalcos, veracruz, mexico, exhibits a moderate, but significant, level of permethrin resistance. unlike other highly permethrin resistant strains, the cz strain does not have a mutation within the sodium channel gene that results in target-site insensitivity. however, the cz strain possesses a substantial increase in general and permethrin esterase activity relative to highly permethrin resistant and control strains suggesting the ...200212403427
molecular diagnosis of pyrethroid resistance in mexican strains of boophilus microplus (acari: ixodidae).polymerase chain reaction (pcr) diagnostic assays were used to identify possible resistance-associated roles of two amino acid substitutions found in pyrethroid resistance-associated genes of boophilus microplus (canestrini). individual larvae from the san felipe target site resistant strain and the coatzacoalcos (cz) metabolic resistant strain were separated into resistant and susceptible groups by larval packet bioassays and analyzed by pcr. a phe --> ile amino acid mutation in the sodium chan ...200212349861
allele frequency and gene expression of a putative carboxylesterase-encoding gene in a pyrethroid resistant strain of the tick boophilus microplus.we utilized rna northern blot analysis and ribonuclease protection assays (rpa) to study the mrna expression level of a putative carboxylesterase-encoding gene from several strains of boophilus microplus (canestrini). both the northern analysis and rpas indicated that an esterase transcript was more abundant in the pyrethroid resistant strain, coatzacoalcos (cz), compared to a susceptible control strain and a resistant strain whose pyrethroid resistance is mediated through a target site insensit ...200212213237
cloning and partial characterization of a boophilus microplus (acari: ixodidae) glutathione s-transferase.a cdna of glutathione s-transferase (gst) was isolated from a cdna library of salivary glands of boophilus microplus. the recombinant protein was purified by glutathione affinity chromatography and assayed upon the chromogenic substrate cdnb. the 864 bp cloned fragment was sequenced and showed an open reading frame coding for a protein of 220 amino acids. expression of the gst gene was tested by rt-pcr in tick tissues and larvae mrna. comparison of the deduced amino acid sequence with gsts from ...200212044491
in vitro generation of organophosphate resistant boophilus microplus (acari: ixodidae) cell lines.three organophosphate resistant boophilus microplus canestrini cell lines were generated by exposing b. microplus viii-scc cell line to incrementally increased toxic concentrations of the acaricide coumaphos. the development of resistance was evidenced by lc50 values elevated over those of control cells. the resistant cell lines selected in higher concentrations of organophosphate, designated c44 and c54, also had significantly slower duplication rates than a resistant cell line selected in lowe ...200211931027
in vitro efficacy of extracts of melia azedarach against the tick boophilus microplus.the efficacy of ripe fruit extracts of melia azedarach l. (rutales: meliaceae) was evaluated against the tick, boophilus microplus (canestrini) (acari: ixodidae). ripe fruits of m. azedarach dried and powdered were extracted by soxhlet apparatus successively using hexane, chcl3 and 96% aqueous ethanol. larvae and engorged females were immersed in decreasing concentrations from 0.25% to 0.015% of each extract. the mortality of larvae was evaluated 24, 72 and 168 h after treatment. the effectivene ...200312823842
a boophilus microplus vitellin-degrading cysteine endopeptidase.here we describe the purification and characterization of a vitellin (vt) degrading cysteine endopeptidase (vtdce) from eggs of the hard tick boophilus microplus. a homogeneous enzyme preparation was obtained by chromatographic fractionation on ion-exchange and gel filtration columns and an autolysis step. this step consisted of incubation of a semipurified enzyme (after the first ion-exchange chromatography) at ph 4.0 that dissociated the enzyme from vt, to which vtdce is naturally tightly asso ...200312636353
proteomics in vaccinology and immunobiology: an informatics perspective of the immunone.the postgenomic era, as manifest, inter alia, by proteomics, offers unparalleled opportunities for the efficient discovery of safe, efficacious, and novel subunit vaccines targeting a tranche of modern major diseases. a negative corollary of this opportunity is the risk of becoming overwhelmed by this embarrassment of riches. informatics techniques, working to address issues of both data management and through prediction to shortcut the experimental process, can be of enormous benefit in leverag ...200314688414
detection of antibodies to anaplasma phagocytophilum and ehrlichia chaffeensis antigens in sera of korean patients by western immunoblotting and indirect immunofluorescence assays.two hundred seventy one serum samples from south korean patients were tested to detect antibodies against anaplasma phagocytophilum (the human granulocytic ehrlichiosis agent) and ehrlichia chaffeensis (the human monocytic ehrlichiosis agent) by indirect fluorescent-antibody assay (ifa) and the western blot assay. these sera were collected from patients with symptoms of high fever. the rate of seropositivity for orientia tsutsugamushi was 50.9% by ifa at the public health & environmental researc ...200314607867
pcr-based detection of the transovarial transmission of uruguayan babesia bovis and babesia bigemina vaccine strains.bovine babesiosis is responsible for serious economic losses in uruguay. haemovaccines play an important role in disease prevention, but concern has been raised about their use. it is feared that the attenuated babesia bovis and babesia bigemina vaccine strains may be transmitted by the local tick vector boophilus microplus, and that reversion to virulence could occur. we therefore investigated the possibility that these strains could be transmitted via the transovarial route in ticks using a ba ...200314621315
inheritance of resistance to flumethrin in the mexican aldama strain of the cattle tick boophilus microplus (acari: ixodidae).the objective of this study was to evaluate the inheritance mode of resistance to flumethrin in the mexican aldama boophilus microplus strain. two mexican strains were used, the chiapas susceptible (ss), and the aldama flumethrin-resistant from tamaulipas. six steers weighing ca. 250 kg were randomly assigned for each of six crosses: the susceptible (ss), resistant (rr), and the f1 (rs, sr) reciprocal crosses and f2 (rs x rs and sr x sr). the reciprocal crosses were made to evaluate maternal and ...200314756408
experimental transmission of an unnamed bovine babesia by hyalomma spp., haemaphysalis longicornis and boophilus microplus.experiments were undertaken to determine the mode of transmission to cattle of an unnamed babesia sp. by hyalomma anatolicum anatolicum, hyalomma detritum, hy. rufipes koch, haemaphysalis longicornis and boophilus microplus. the unnamed babesia species designated babesia u sp. was isolated by infesting cattle with nymphs from female hy. a. anatolicum ticks collected from xinjiang province. adults of laboratory reared hy. a. anatolicum, hy. detritum and hy. rufipes koch were infected with babesia ...200314519316
antigens and alternatives for control of anaplasma marginale infection in cattle.anaplasmosis, a tick-borne cattle disease caused by the rickettsia anaplasma marginale, is endemic in tropical and subtropical areas of the world. the disease causes considerable economic loss to both the dairy and beef industries worldwide. analyses of 16s rrna, groesl, and surface proteins have resulted in the recent reclassification of the order rickettsiales. the genus anaplasma, of which a. marginale is the type species, now also includes a. bovis, a. platys, and a. phagocytophilum, which w ...200314557295
experimental immunisation of crossbred cattle with glycoproteins isolated from the larvae of hyalomma anatolicum anatolicum and boophilus microplus.in india, control of tick infestations is a major problem facing the owners of highly productive crossbred cattle. to develop suitable immunoprotective measures against the multitick infestations, specific problem encountered by the indian farmers, an attempt has been made to identify candidate protein molecules in the larvae of hyalomma anatolicum anatolicum and boophilus microplus. employing two steps affinity chromatography method, glycoproteins of 34 and 29 kda were isolated from h. a. anato ...200314974694
[relative frequency of boophilus microplus (acari: ixodidae) in bovines (bos taurus and b. indicus) in 8 ecological zones of costa rica].the research on the relative abundancy of boophilus microplus took place in ten farms, distributed in eight ecological zones (ez) and two rainfall systems of costa rica. monthly visits were made to pick up ticks larger than 4 mm from the right side of the animals. the total number of ticks was increased by two and divided between the total of sampled bovines per farm. farm visits were adjusted to animals bath to allow the recovery of the tick population. b. microplus was detected in all sampled ...200315162736
the innate immune response in calves to boophilus microplus tick transmitted babesia bovis involves type-1 cytokine induction and nk-like cells in the spleen.the innate immune response to babesia bovis infection in cattle is age-related, spleen-dependent and, in stabilate inoculated calves, has type-1 characteristics, including the early induction of il-12 and ifn-gamma. in this study with three calves, parameters of innate immunity were followed for 2 weeks after tick transmission of b. bovis. each calf survived the acute disease episode without drug intervention, and responded with increased levels of plasma interferon-gamma and type-1 cytokine exp ...200312940961
rhipicephalus sanguineus trypsin inhibitors present in the tick larvae: isolation, characterization, and partial primary structure determination.blood sucking animals are a rich source of proteinase inhibitors mainly those that interfere in their host hemostatic systems. the tick rhipicephalus sanguineus is an ectoparasite of dogs and other animals. the aims of this work were the purification and characterization of serine proteinase inhibitors present in r. sanguineus larvae (rsti). the inhibitors (rsti) were isolated by affinity chromatography on trypsin-sepharose and ion exchange chromatographies in resource q and mono s columns. thes ...200312941299
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
heparan sulfate glycosaminoglycan expression in the intestinal tract and ovary of fully engorged adult females of the cattle tick boophilus microplus and in their laid eggs. 200312946856
beauveria bassiana isolated from engorged females and tested against eggs and larvae of boophilus microplus (acari: ixodidae).the purpose of this work was to evaluate the in vitro virulence of three isolates of beauveria bassiana to eggs and larvae of the tick boophilus microplus. the fungus tested were isolated from engorged females of b. microplus collected on the field, and identified as bb28, bb29 and bb30. these isolates were evaluated by immersion of eggs and larvae in suspensions with different conidial concentrations: 10(8), 10(7), 10(6) and 10(5) conidia/ml and compared to the control groups. in the treated eg ...200312964182
assessment of a low virulence australian isolate of anaplasma marginale for pathogenicity, immunogenicity and transmissibility by boophilus microplus.a 14-year-old cow (dawn) born and kept in a boophilus microplus-free region gave birth to a calf, which showed the presence of an anaplasma marginale infection after splenectomy. the calf's grand dam was from a b. microplus infected area and we assume the infection originated via the transplacental route over two generations. an isolate, prepared from the calf, had similar or lower pathogenicity as anaplasma centrale, and previously exposed steers were resistant to challenge by four a. marginale ...200314651881
expression of equi merozoite antigen 2 during development of babesia equi in the midgut and salivary gland of the vector tick boophilus microplus.equi merozoite antigens 1 and 2 (ema-1 and ema-2) are babesia equi proteins expressed on the parasite surface during infection in horses and are orthologues of proteins in theileria spp., which are also tick-transmitted protozoal pathogens. we determined in this study whether ema-1 and ema-2 were expressed within the vector tick boophilus microplus. b. equi transitions through multiple, morphologically distinct stages, including sexual stages, and these transitions culminate in the formation of ...200314662988
resistance to coumaphos and diazinon in boophilus microplus (acari: ixodidae) and evidence for the involvement of an oxidative detoxification mechanism.the levels of resistance to two organophosphate acaricides, coumaphos and diazinon, in several mexican strains of boophilus microplus (canestrini) were evaluated using the fao larval packet test. regression analysis of lc50 data revealed a significant cross-resistance pattern between those two acaricides. metabolic mechanisms of resistance were investigated with synergist bioassays. piperonyl butoxide (pbo) reduced coumaphos toxicity in susceptible strains, but synergized coumaphos toxicity in r ...200314680115
advances in the identification and characterization of protective antigens for recombinant vaccines against tick infestations.ticks are economically important ectoparasites of domestic and wild animals and are considered to be second worldwide to mosquitoes as vectors of human pathogens. current control methods for ticks, based primarily on the use of acaricides, have had limited efficacy in the reduction of tick infestations and the use of acaricides is often accompanied by serious drawbacks, including selection of acaricide-resistant ticks and environmental contamination. development of improved vaccines against tick ...200314711342
biochemical detection of esterases in the adult female integument of organophosphate-resistant boophilus microplus (acari: ixodidae).esterase activity was present in the integument of adult female boophilus microplus (canestrini) ticks that are resistant to organophosphates (op). three esterases were purified from adult integument, which hydrolyze the substrates p-nitrophenylacetate and beta-naphthyl acetate after comparison of op-resistant strain and an op-susceptible strains. the esterases purified by ion-exchange chromatography were characterized using different esterase inhibitors; eserine sulfate, diethyl p-nitrophenyl p ...200312597652
antibacterial hemoglobin fragments from the midgut of the soft tick, ornithodoros moubata (acari: argasidae).midgut contents of ornithodoros moubata showed strong antibacterial activity against staphylococcus aureus. a combination of reversed-phase chromatography and mass spectrometric analysis was used to isolate two antibacterial peptides from the tick midgut lumen. partial amino acid sequences by edman degradation of these two peptides showed they are identical with the 1-11 and 3-19 portions of rabbit a hemoglobin. host rabbit a hemoglobin appears to be cleaved between met32 and phe33 to produce th ...200312597657
factors affecting the detachment rhythm of engorged boophilus microplus female ticks (acari: ixodidae) from charolais steers in new caledonia.as in most parts of the world where the cattle tick boophilus microplus is established, resistance of ticks to acaricides occurs in new caledonia. in order to implement laboratory resistance tests on larvae, engorged females collected in suspected farms are necessary. investigations on the detachment schedule of the engorged females were conducted to explain certain field situations such as the lack or scarcity of engorged females on highly infested cattle driven from the pasture to the pen in t ...200312623211
arsenic in australian environment: an overview.the most common source of elevated as concentrations in the australian environment are attributable to anthropogenic activities. mining activities have contributed to the contamination of soil and water primarily in western australia and victoria. however, other anthropogenic activities such as agriculture, forestry and industry have also contaminated soil and water at a localized scale. currently there are over 1000 as contaminated sites previously used as cattle dips for eradicating cattle tic ...200312635829
induction of mosquitocidal activity in mice immunized with anopheles gambiae midgut cdna.vaccines that induce mosquito-killing (mosquitocidal) activity could substantially reduce the transmission of certain mosquito-borne diseases, especially vaccines against african malaria vectors, such as the mosquito anopheles gambiae. to generate and characterize antimosquito immunity we immunized groups of mice with two individual a. gambiae midgut cdnas, ag-aper1 (a secreted peritrophic matrix protein) and agmuc1 (a midgut-bound mucin), and an a. gambiae midgut cdna library from blood-fed mos ...200312654823
a new intracellular pathway of haem detoxification in the midgut of the cattle tick boophilus microplus: aggregation inside a specialized organelle, the hemosome.the hard tick boophilus microplus ingests large volumes of cattle blood, as much as 100 times its own mass before feeding. huge amounts of haem are produced during haemoglobin digestion, which takes place inside acidic lysosomal-type vacuoles of the digest cells of the midgut. haem is a promoter of free radical formation, so haemoglobin digestion poses an intense oxidative challenge to this animal. in the present study we followed the fate of the haem derived from haemoglobin hydrolysis in the d ...200312682102
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
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
efficacy of various concentrations of coumaphos to control adult, nymphal, and larval stages of an organophosphate-resistant strain of boophilus microplus on infested cattle.to evaluate the efficacy of coumaphos, an organophosphate (op) acaricide, at concentrations up to 2 times higher than the highest concentration required by the us eradication program against all stages of an op-resistant strain of boophilus microplus in experimentally infested cattle.200312828252
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
internal and external mycoflora of the american dog tick, dermacentor variabilis (acari: ixodidae), and its ecological implications.scopulariopsis brevicaulis, the anamorph of microascus brevicaulis (microascaceae, ascomycota), has been identified in the body contents of the tick dermacentor variabilis. after topical application of the fungal inoculum, tick mortality was marked. this is the first account describing the internal mycoflora of d. variabilis with a novel technique used to recover potential biological control agents.200312902299
transmission of anaplasma marginale by boophilus microplus: retention of vector competence in the absence of vector-pathogen interaction.whether arthropod vectors retain competence for transmission of infectious agents in the long-term absence of vector-pathogen interaction is unknown. we addressed this question by quantifying the vector competence of two tick vectors, with mutually exclusive tropical- versus temperate-region distributions, for genetically distinct tropical- and temperate-region strains of the cattle pathogen anaplasma marginale. the tropical cattle tick boophilus microplus, which has been eradicated from the con ...200312904396
effect of moxidectin against natural infestation of the cattle tick boophilus microplus (acarina: ixodidae) in the mexican tropics.the study was divided in to two trials and carried out in a ranch in eastern yucatan state, mexico. in the first trial, two groups of 15 bostaurusxbosindicus heifers, 6-12 month of age and naturally infested with boophilus microplus ticks were used. heifers in group 1 were treated with a 1% injectable formulation of moxidectin at the dose of 0.20mg/kg body weight by subcutaneous injection. the other group remained as untreated controls. number of immature and engorging female ticks were assessed ...200312531295
four serine proteinase inhibitors (serpin) from the brown ear tick, rhiphicephalus appendiculatus; cdna cloning and preliminary characterization.while development of an anti-boophilus microplus vaccine is advanced and practical, work on other economically important ticks such as rhipicephalus appendiculatus is still in its infancy. guess pcr primers, designed from a consensus amino acid sequence (navykfg) motif were used with rapid amplification of cdna ends (race) to clone four cdnas encoding serine proteinase inhibitors (serpin) from the brown ear tick rhipicephalus appendiculatus. the four genes designated as r. appendiculatus serpin ...200312535684
functional analysis of a g protein-coupled receptor from the southern cattle tick boophilus microplus (acari: ixodidae) identifies it as the first arthropod myokinin receptor.the myokinins are invertebrate neuropeptides with myotropic and diuretic activity. the lymnokinin receptor from the snail lymnaea stagnalis (mollusca) has been the only previously identified myokinin receptor. we had cloned a g protein-coupled receptor (af228521) from the tick boophilus microplus (arthropoda: acari), 40% identical to the lymnokinin receptor, that we have now expressed in cho-k1 cells. myokinins at nanomolar concentrations induced intracellular calcium release, as measured by flu ...200312542633
regulation of extracellular chitinases and proteases in the entomopathogen and acaricide metarhizium anisopliae.metarhizium anisopliae infects insects and ticks via a combination of specialized structures and cuticle degradation. hydrolytic enzymes are accepted as key factors for the penetration step. the search for pathogenicity determinants has demonstrated that the process is multifactorial. host specificity is an important factor to be addressed. the study of the enzymes produced during infection is important to discover those with a role in the process. to address some of the enzymes that take part d ...200312567244
factors related to cattle infestation level and resistance to acaricides in boophilus microplus tick populations in new caledonia.boophilus microplus, even in the absence of babesiosis, is a major disease of the cattle in new caledonia where the particular farming system associates continental european breeds and a tropical climate tempered by the pacific ocean. in order to have a better understanding of the factors involved in cattle tick infestation, to decrease the possible wastage and use of chemicals and to increase the lifetime of the acaricides, the veterinary authorities investigated the conditions of the chemical ...200312581586
global change and human vulnerability to vector-borne diseases.global change includes climate change and climate variability, land use, water storage and irrigation, human population growth and urbanization, trade and travel, and chemical pollution. impacts on vector-borne diseases, including malaria, dengue fever, infections by other arboviruses, schistosomiasis, trypanosomiasis, onchocerciasis, and leishmaniasis are reviewed. while climate change is global in nature and poses unknown future risks to humans and natural ecosystems, other local changes are o ...200414726459
molecular cloning and functional expression of a serotonin receptor from the southern cattle tick, boophilus microplus (acari: ixodidae).a full-length cdna encoding a 5-hydroxytryptamine (5-ht) receptor from the southern cattle tick, boophilus microplus, was isolated using a strategy based on sequence homology among g protein-coupled receptors. the deduced amino acid sequence revealed highest identity with drosophila melanogaster 5ht-dro2a (z11489, 50.8%) and 5ht-dro2b (z11490, 49.5%) receptors. the receptor was transiently expressed in mammalian hek293 cells, and western blot analysis showed the expected 43.3 kda band. in these ...200414728666
conservation of babesia bovis small heat shock protein (hsp20) among strains and definition of t helper cell epitopes recognized by cattle with diverse major histocompatibility complex class ii haplotypes.babesia bovis small heat shock protein (hsp20) is recognized by cd4+ t lymphocytes from cattle that have recovered from infection and are immune to challenge. this candidate vaccine antigen is related to a protective antigen of toxoplasma gondii, hsp30/bag1, and both are members of the alpha-crystallin family of proteins that can serve as molecular chaperones. in the present study, immunofluorescence microscopy determined that hsp20 is expressed intracellularly in all merozoites. importantly, hs ...200414742557
effect of acaricides on the activity of a boophilus microplus glutathione s-transferase.in the present study, we report the effect of several acaricides on the enzyme activity of a boophilus microplus recombinant glutathione s-transferase (rgst). gst was expressed in escherichia coli and was purified with glutathione (gsh) affinity column chromatography. the kinetic constants were determined by reacting gst with the substrates 1-chloro-2,4-dinitrobenzene (cdnb) and glutathione. we report the effect of several acaricides on the enzyme activity of rgst. some acaricides (ethion, amitr ...200414746982
a sero-epidemiological survey of blood parasites in cattle in the north-eastern free state, south africa.a survey to determine the incidence of parasites in cattle (n = 386) was conducted in the north eastern free state between august 1999 and july 2000. giemsa-stained blood smears were negative for blood parasites. a total of 94% of the cattle were sero-positive for babesia bigemina by indirect fluorescent antibody test while 87% were sero-positive for anaplasma by enzyme-linked immunosorbent assay. the observation of negative blood smears but high incidence of positive serological results for ana ...200415185577
therapeutic and persistent efficacy of a single application of doramectin applied either as a pour-on or injection to cattle infested with boophilus microplus (acari: ixodidae).the efficacy of a single treatment with a pour-on application or a subcutaneous injection of the macrocyclic lactone endectocide, doramectin, was evaluated in separate trials on hereford heifers infested with boophilus microplus (canestrini). significantly fewer ticks per calf were recovered from both groups of treated animals than from the complimentary untreated calves. the mean weights of engorged females and egg masses from both pour-on-treated and injectable-treated calves were also signifi ...200415185941
control of an organophosphate-resistant strain of boophilus microplus (acari: ixodidae) infested on cattle after a series of dips in coumaphos applied at different treatment intervals.efficacy of multiple dip treatments (one to three) at 0.3% active ingredient (ai) coumpahos applied at 7- or 10-d intervals was determined against organophosphate (op)-resistant boophilus microplus (canestrini). none of the treatments totally prevented repletion of all females. in the 7 d after one treatment, the percentage of reduction of female ticks was 24.8%, whereas in the 10 d after one treatment, the reduction of female numbers was 47.1%. application of two or three dips at either interva ...200415185959
entomopathogenic potential of metarhizium anisopliae isolated from engorged females and tested in eggs and larvae of boophilus microplus (acari: ixodidae).the purpose of this work was to evaluate the in vitro virulence of three isolates of metarhizium anisopliae var. anisopliae to eggs and larvae of the tick boophilus microplus. the fungus tested was isolated from engorged females of b. microplus collected in the field, and identified as ma01, ma02 e ma04. these isolates were evaluated by immersion of eggs and larvae in suspension with different conidial concentrations: 10(5), 10(6), 10(7) e 10(8) conidia/ml. in each isolate there was a treatment ...200415266598
effect of invertebrate serine proteinase inhibitors on carrageenan-induced pleural exudation and bradykinin release.the carrageenan model of pleurisy is described as temporal plasma exudation (1-5 h) with extensive neutrophil infiltration and release of proteinases into the pleural cavity. the aim of this work was to study the effects of serine proteinase inhibitors on the inflammatory process induced by administration of carrageenan to the rat pleural cavity and on release of kinins in pleural exudate. pleurisy was induced by injecting carrageenan and serine proteinase inhibitors simultaneously into the pleu ...200415313437
crystallization and preliminary x-ray diffraction analysis of help, a heme lipoprotein from the hemolymph of the cattle tick boophilus microplus.the main protein present in the hemelymph of the cattle tick boophilus microplus is a lipoprotein able to bind heme (help). it has an apparent molecular weight of 354 000 da and is composed of two polypeptide chains found in stoichiometric amounts. it contains 33% lipids. the protein was crystallized using the hanging-drop vapour-diffusion method in the presence of 1,6-hexanediol as a precipitant. x-ray diffraction data were collected to 2.1 a resolution using a synchrotron-radiation source. the ...200415333941
a thrombin inhibitor from the ixodid tick, amblyomma hebraeum.a novel thrombin inhibitor named amblin was identified from the haemolymph of the ixodid (hard) tick, amblyomma hebraeum, and the coding cdna was isolated from a tick cdna library. this cdna codes for a preprotein of 166 amino acids, including a predicted signal peptide composed of 15 amino acids n-terminal to the mature amblin. the 151-amino-acid mature amblin contains 14 cysteines and two kunitz-like domains. it displays high sequence similarity with a tissue factor pathway inhibitor (tfpi), i ...200415527983
the cattle tick antigen, bm95, expressed in pichia pastoris contains short chains of n- and o-glycans.bm95 is an antigen isolated from boophilus microplus strains with low susceptibility to antibodies developed in cattle vaccinated with the recombinant bm86 antigen (gavac, heberbiotec s.a., cuba). it is a bm86-like surface protein, which by similarity contains seven egf-like domains and a lipid-binding gpi-anchor site at the c-terminal region. the primary structure of the recombinant (rbm95) protein expressed in pichia pastoris was completely verified by lc/ms. the four potential glycosylation s ...200415542059
boophilus microplus tick larvae, a rich source of kunitz type serine proteinase inhibitors.serine proteinase inhibitors from boophilus microplus tick larvae (bmtis) were purified by affinity chromatography on a trypsin-sepharose column. bmtis presented molecular weight between m(r) 6200 and 18,400 and inhibitory activity for trypsin, hupk (human plasma kallikrein) and neutrophil elastase. using ion exchange chromatography, bmtis were separated in several protein pools named bmti-a to bmti-f and bmti-1 to bmti-7. all bmti forms presented inhibitory activity for trypsin with apparent di ...200415556274
immunization effect of recombinant p27/30 protein expressed in escherichia coli against the hard tick haemaphysalis longicornis (acari: ixodidae) in rabbits.we investigated the induction of resistance to haemaphysalis longicornis infestation in rabbits that had been immunized with recombinant h. longicornis p27/30 protein. the success of immunological control methods is dependent upon the use of potential key antigens as tick vaccine candidates. previously, we cloned a gene encoding 27 kda and 30 kda proteins (p27/30) of h. longicornis, and identified p27/30 as a troponin i-like protein. in this study, rabbits that were immunized with recombinant p2 ...200415591837
detection of anaplasma marginale dna in larvae of boophilus microplus ticks by polymerase chain reaction.boophilus microplus larvae from two different sources were used for the detection of anaplasma marginale dna: larvae a, which were collected from a pasture of an endemic farm, and larvae b, which originated from engorged female ticks fed on calves with no clinical signs of disease and with low rickettsemia (approximately 0.01 to 1.0%). larvae a were collected monthly, from january to may in 2001. two hundred engorged female ticks fed on calves that provided larvae b were divided into groups of 1 ...200415604475
babesia bigemina: sporozoite isolation from boophilus microplus nymphs and initial immunomolecular characterization.it has been hypothesized that babesial sporozoites express specific antigens that induce protective immunologic responses in cattle. however, they remain uncharacterized, partly for lack of research on the sporozoite stage of babesia spp. this field suffers from complete knowledge of parasite development in the tick salivary gland; limited amounts of sporozoites from ticks, and a lack of protocols for induction and purification of sporozoites. in this work, boophilus microplus larvae infected wi ...200415604497
gene discovery in boophilus microplus, the cattle tick: the transcriptomes of ovaries, salivary glands, and hemocytes.the quest for new control strategies for ticks can profit from high throughput genomics. in order to identify genes that are involved in oogenesis and development, in defense, and in hematophagy, the transcriptomes of ovaries, hemocytes, and salivary glands from rapidly ingurgitating females, and of salivary glands from males of boophilus microplus were pcr amplified, and the expressed sequence tags (est) of random clones were mass sequenced. so far, more than 1,344 est have been generated for t ...200415604500
field challenge of cattle vaccinated with a combined babesia bovis and babesia bigemina frozen immunogen.to determine the optimal dose of a combined, frozen immunogen containing in vitro culture-derived strains of babesia bovis and babesia bigemina, twenty-four 14-month-old bos taurus steers from a boophilus microplus-free area in northern mexico were used in this experiment. cattle were randomly allocated into six groups with four animals each, and were intramuscularly inoculated as follows: group 1 (control animals) were administered with normal bovine erythrocytes; group 2 received 1 x 10(7) b. ...200415604506
protection of dairy cows immunized with tick tissues against natural boophilus microplus infestations in thailand.boophilus microplus has a major impact on cattle production, and an antitick vaccine would be a valuable tool for control of this important ectoparasite in thailand. previous work has shown that immunization of hosts with different tick tissues has different implications regarding tick feeding and fecundity under experimental conditions. the purpose of this study was to assess the effects of immunization of dairy cattle with b. microplus salivary gland or midgut extracts on natural infestations ...200415604508
immune response to babesia bigemina infection in pregnant cows.babesiosis is a tick-borne disease of cattle caused by babesia bigemina and babesia bovis and is transmitted by the tick vector boophilus microplus. in this study, we investigate b. bigemina infection regarding the clinical infection, t cell distribution, and cytokine profile during the acute phase of an experimental infection in pregnant cows.200415604509
reduced incidence of babesia bigemina infection in cattle immunized against the cattle tick, boophilus microplus.boophilus microplus is an important vector of bovine disease agents having a major economic impact on cattle production in many tropical and subtropical countries. components of tick saliva that enable ticks to feed may also facilitate establishment of tick-borne pathogens in the vertebrate host. it has been suggested that acquired resistance against molecules in tick saliva could inhibit parasite transmission, and there is increasing evidence to support this hypothesis. the effect of immune res ...200415604511
laboratory evaluation of the compatibility and the synergism between the entomopathogenic fungus beauveria bassiana and deltamethrin to resistant strains of boophilus microplus.beauveria bassiana is one of the most promising agents for use as a bioacaricide to control the cattle tick boophilus microplus, responsible for economic losses and transmission of infectious diseases. with the aim of optimizing the efficacy of chemical products, as well as the use of entomopathogens, the objective of the present study was to evaluate the compatibility and the synergism between this fungus and the drug deltamethrin on a strain of b. microplus that is resistant to this product.200415604512
complete genome sequencing of anaplasma marginale reveals that the surface is skewed to two superfamilies of outer membrane proteins.the rickettsia anaplasma marginale is the most prevalent tick-borne livestock pathogen worldwide and is a severe constraint to animal health. a. marginale establishes lifelong persistence in infected ruminants and these animals serve as a reservoir for ticks to acquire and transmit the pathogen. within the mammalian host, a. marginale generates antigenic variants by changing a surface coat composed of numerous proteins. by sequencing and annotating the complete 1,197,687-bp genome of the st. mar ...200415618402
detection of ehrlichial dna in haemaphysalis ticks recovered from dogs in japan that is closely related to a novel ehrlichia sp. found in cattle ticks from tibet, thailand, and africa.tick dna samples from dogs in japan were examined for ehrlichia infection by 16s rrna gene-based pcr and sequencing. three positive samples were detected from haemaphysalis ticks, and higher levels of similarity (98.46 to 99.06%) were found to recently detected ehrlichia spp. from cattle ticks in tibet, thailand, and africa.200415004117
infection rate of babesia spp. sporokinetes in engorged boophilus microplus from an area of enzootic stability in the state of minas gerais, brazil.the infection rates of babesia sporokinetes in engorged boophilus microplus were evaluated during a 2-year period in a dairy farm located in an area of enzootic stability. every 14 days engorged females were collected from calves and from adult animals. ticks were incubated at 27 +/- 0.5 degree c and 80-90% relative humidity and babesia infection rates were determined by microscopic examination of giemsa-stained hemolymph smears. after 52 collections, 2105 ticks were obtained, from which 982 wer ...200415049079
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
detection and characterization of amitraz resistance in the southern cattle tick, boophilus microplus (acari: ixodidae).amitraz, a formamidine acaricide, plays an important role in the control of the southern cattle tick, boophilus microplus (canestrini), and other tick species that infest cattle, dogs, and wild animals. although resistance to amitraz in b. microplus was previously reported in several countries, the actual measurement of the level of amitraz resistance in ticks has been difficult to determine due to the lack of a proper bioassay technique. we conducted a survey, by using a newly reported techniqu ...200415061278
displacement of boophilus decoloratus by boophilus microplus in the soutpansberg region, limpopo province, south africa.boophilus ticks (n = 25,987) were collected from cattle at 30 communal dip tanks and five commercial farms in the soutpansberg region, limpopo province, south africa, between may 1999 and december 2001. only 6.6% were boophilus decoloratus, while 93.4% were boophilus microplus, a tick that had not been reported from this area previously. b. microplus was the most common boophilus tick on communal dip tank cattle, while b. decoloratus was more commonly found on commercial farms. where the two spe ...200415139085
production and biochemical characterization of the recombinant boophilus microplus bm95 antigen from pichia pastoris.the new antigen bm95 from the cattle tick boophilus microplus was recently isolated, cloned and expressed in the methylotrophic yeast pichia pastoris. the recombinant protein has shown to induce protection in cattle against infestations of b. microplus under controlled and production conditions. in this paper we report the production and large-scale purification of the bm95 protein, following a simple and cost-effective process. the antigen was obtained highly aggregated, forming particles rangi ...200415139278
application of representational difference analysis to identify sequence tags expressed by metarhizium anisopliae during the infection process of the tick boophilus microplus cuticle.metarhizium anisopliae is a well-characterized biocontrol agent of a wide range of plagues, including insects and acari. to identify genes involved in the infection process, representational difference analysis was performed using cdna generated from germinated conidia of m. anisopliae in the tick boophilus microplus cuticle, and cdna generated during fungal growth in glucose-rich medium. sequence determination of approximately 135 clones and comparison analysis using public databases led to the ...200415142621
cloning, expression and partial characterization of a haemaphysalis longicornis and a rhipicephalus appendiculatus glutathione s-transferase.the ticks haemaphysalis longicornis and rhipicephalus appendiculatus are important parasites worldwide. the current method for control of cattle ticks involves the use of chemicals. nevertheless, parasite resistance is an ever increasing global problem. glutathione s-transferases (gsts) play a central role in detoxication of xenobiotic and endogenous compounds. several authors have noted that an increase in gst activity is associated with resistance to insecticides and acaricides. in the present ...200415157234
a comparison of the immunosuppressive effects of salivary gland extracts from two laboratory strains of boophilus microplus.this study addresses three questions related to the immune response of cattle to tick salivary gland extracts. firstly, is there a difference in the inhibition of proliferation of concanavalin a (cona) stimulated bovine lymphocytes induced by salivary gland extracts of the n and y strains of boophilus microplus? second, is there a difference in the development rate of the y and n tick strains? third, does the host affect the inhibitory effect of salivary gland extract on the proliferation of con ...200415157766
cysteine-rich antimicrobial peptides of the cattle tick boophilus microplus: isolation, structural characterization and tissue expression profile.antimicrobial peptides (amps) are components of the immune system of both vertebrate and invertebrate animals. this study describes the isolation, primary structure, cdna cloning, and tissue expression profile of two cysteine-rich amps from the hemolymph of the cattle tick boophilus microplus. a 10,204 da polypeptide, with six cysteine residues and no sequence similarity to any known molecule, was isolated from the cell-free hemolymph. because of its sequence originality, this peptide was named ...200414642886
genes transcribed in the salivary glands of female rhipicephalus appendiculatus ticks infected with theileria parva.we describe the generation of an auto-annotated index of genes that are expressed in the salivary glands of four-day fed female adult rhipicephalus appendiculatus ticks. a total of 9162 est sequences were derived from an uninfected tick cdna library and 9844 ests were from a cdna library from ticks infected with theileria parva, which develop in type iii salivary gland acini. there were no major differences between abundantly expressed ests from the two cdna libraries, although there was evidenc ...200415475305
factors that influence the prevalence of acaricide resistance and tick-borne diseases.this manuscript provides a summary of the results presented at a symposium organized to accumulate information on factors that influence the prevalence of acaricide resistance and tick-borne diseases. this symposium was part of the 19th international conference of the world association for the advancement of veterinary parasitology (waavp), held in new orleans, la, usa, during august 10-14, 2003. populations of southern cattle ticks, boophilus microplus, from mexico have developed resistance to ...200415476966
babesia bigemina sexual stages are induced in vitro and are specifically recognized by antibodies in the midgut of infected boophilus microplus ticks.babesia bigemina, a causative agent of bovine babesiosis, is transmitted from one bovine to another only by infected ticks. the life cycle of b. bigemina includes a sexual phase in the tick host; however, molecules from sexual stages of any babesia species have not been characterized. this is the first report of the induction of sexual stages of any babesia species in vitro, free of tick antigens. intraerythrocytic parasites were cultured in vitro for 20h using an induction medium. extraerythroc ...200415491585
molecular cloning and sequence analysis of cdnas encoding for boophilus microplus, haemaphysalis longicornis and rhipicephalus appendiculatus actins.the nucleotide and deduced amino acid sequences of the actins from ticks, boophilus microplus, haemaphysalis longicornis and rhipicephalus appendiculatus, have been determined. nucleotide sequence analysis showed open reading frames of 1128-nucleotide-long encoding proteins of 376 amino acids with a predicted molecular weight of 41.82 kda each. comparison between the nucleic acid and deduced amino acid sequences as well as structural and phylogenetic analyses of these genes confirmed the high si ...200415631908
eprinomectin pour-on for control of boophilus microplus (canestrini) ticks (acari: ixodidae) on cattle.the efficacy of a commercial pour-on formulation of eprinomectin, a macrocyclic lactone, against experimental infestations of boophilus microplus (canestrini) ticks was evaluated in two trials involving 27 bos taurus calves. the first trial was designed to evaluate the effects of a single treatment at a dose of 0.5 mg/kg of body weight against standard size b. microplus females (4.5-8.0 mm long). a significant reduction in tick numbers (p<0.05, wilcoxon test) was observed between treated calves ...200415631909
integrated control of boophilus microplus ticks in cuba based on vaccination with the anti-tick vaccine gavac.boophilus microplus has developed resistance against a range of chemical acaricides which has stimulated the development of alternative methods such as vaccination against ticks. in cuba, the bm86-based recombinant vaccine gavac has been successfully used in a number of controlled laboratory and field trials in cattle against b. microplus. in this paper, we have evaluated gavac in a large scale field trial wherein 588,573 dairy cattle were vaccinated with the aim to reduce the number of acaricid ...200415651533
lack of infectivity of a brazilian anaplasma marginale isolate for boophilus microplus ticks.previous studies have shown that one brazilian anaplasma marginale isolate presents an inclusion appendage (tail), while other isolates do not present such inclusion. studies on tick transmission have been carried out with tailless isolates but little is known about transmission of tailed isolates by boophilus microplus. two splenectomized calves were experimentally inoculated with the tailed a. marginale isolate. during ascending rickettsemia, b. microplus larvae, free from hemoparasites, were ...200415740870
steinernema glaseri santa rosa strain (rhabditida: steinernematidae) and heterorhabditis bacteriophora cca strain (rhabditida: heterorhabditidae) as biological control agents of boophilus microplus (acari: ixodidae).the present study was carried out to evaluate the action of steinernema glaseri santa rosa strain and heterorhabditis bacteriophora cca strain as biological control agents of boophilus microplus. engorged females ticks were distributed on petri dishes containing different concentrations of infective juvenile (ij) nematodes (0, 375, 500, 750, 1,500, 2,500, 5,000 and 25,000). the data showed a reduction of approximately 90% in the eggs laid at a concentration of 5,000 s. glaseri ijs and approximat ...200415480784
identification of a third boophilus microplus (acari: ixodidae) cdna presumptively encoding an acetylcholinesterase.oligodeoxynucleotide primers, based on amino acid sequences conserved in known acetylcholinesterases (aches), were used in reverse-transcription polymerase chain reaction (rt-pcr) with mrna from boophilus microplus (canestrini) as the template. primer walking and rapid amplification of cdna ends (race) techniques were used to complete the cdna sequence identified by rt-pcr. the complete b. microplus cdna sequence contained an open reading frame encoding a 620 amino acid protein with a 20 amino a ...200415185924
anti-tick effects of melinis minutiflora and andropogon gayanus grasses on plots experimentally infested with boophilus microplus larvae.our objective in this trial was to investigate the anti-tick effects of molasses grass (melinis minutiflora) and gamba grass (andropogon gayanus) against boophilus microplus, using buffel grass (cenchrus ciliaris) as a control. during a 3-year-period fieldwork was carried out in the tropical, subhumid climate at progreso, municipality of jiutepec, morelos, mexico. experimental plots were established for three treatments with six replicates under a random factorial design in order to evaluate eac ...200415176734
proteolytic activity of boophilus microplus yolk pro-cathepsin d (byc) is coincident with cortical acidification during embryogenesis.in a previous report (parasitology 116 (1998) 525) we isolated and characterized boophilus yolk pro-cathepsin (byc), an aspartic proteinase precursor from the eggs of the hard tick. the present study was designed to characterize the function of byc in the consumption of vitellin (vt), the major yolk protein, during embryogenesis. both purified byc and total egg homogenate proteolytic activity showed a similar ph dependence profile with an acidic optimum. purified byc presented higher activity ag ...200415110865
help, a heme-transporting lipoprotein with an antioxidant role.plasma lipoproteins involved in lipid transport are target for free radical-evoked pathological conditions in several mammalian models. the main hemolymphatic protein of boophilus microplus is a heme-binding lipoprotein (help, for heme lipoprotein) that carries dietary heme produced from degradation of vertebrate hemoglobin to tissues of the tick. addition of heme to phospholipid liposomes resulted in intense lipid peroxidation, which was inhibited by addition of help. help prevented lysis of re ...200414976984
a secondary structural common core in the ribosomal its2 (internal transcribed spacer) of culexspecies from diverse geographical locations.in the present study, sequence and structural analysis of its2 region (the spacer segment between 5.8s and 28s rrna of mature rrna sequences) of 7 culex species belonging to 5 different geographical locations was carried out. alignment of the its2 sequence from the 7 species revealed 8 homologous domains. four species namely c. vishnui, c. annulus, c. pipiens, c. quiquefasciatusshowed high sequence (98-100%) and rna secondary structure similarity. the its2 similarity among different species is h ...200517597853
evolution and origin of merlin, the product of the neurofibromatosis type 2 (nf2) tumor-suppressor gene.merlin, the product of the neurofibromatosis type 2 (nf2) tumor suppressor gene, belongs to the ezrin-radixin-moesin (erm) subgroup of the protein 4.1 superfamily, which links cell surface glycoproteins to the actin cytoskeleton. while merlin's functional activity has been examined in mammalian and drosophila models, little is understood about its evolution, diversity, and overall distribution among different taxa.200516324214
proposal to create subspecies of rickettsia conorii based on multi-locus sequence typing and an emended description of rickettsia conorii.rickettsiae closely related to the malish strain, the reference rickettsia conorii strain, include indian tick typhus rickettsia (ittr), israeli spotted fever rickettsia (isfr), and astrakhan fever rickettsia (afr). although closely related genotypically, they are distinct serotypically. using multilocus sequence typing (mlst), we have recently found that distinct serotypes may not always represent distinct species within the rickettsia genus. we investigated the possibility of classifying ricke ...200515766388
therapeutic and persistent efficacy of a single injection treatment of ivermectin and moxidectin against boophilus microplus (acari: ixodidae) on infested cattle.the effectiveness of a single treatment with either ivermectin or moxidectin was determined by administering a single subcutaneous injection of each endectocide at 200 microg per kg body weight to cattle infested with all parasitic developmental stages (adults, nymphs, and larvae) of boophilus microplus (canestrini). the percentage reduction in the number of females that reached repletion following treatment (outright kill) was 94.8 and 91.1% for ivermectin and moxidectin, respectively. in addit ...200515777005
ticks (acari: ixodoidea: argasidae, ixodidae) of chile.the tick species recorded from chile can be listed under the following headings: (1) endemic or established: argas keiransi estrada-peña, venzal and gonzalez-acuña, a. neghmei kohls and hoogstraal; ornithodoros amblus chamberlin; otobius megnini (dugès); amblyomma parvitarsum neumann; a. tigrinum koch; ixodes auritulus neumann; i. chilensis kohls; i. cornuae arthur, i. sigelos keirans, clifford and corwin; i. stilesi neumann; i. uriae white; rhipicephalus sanguineus koch. (2) probably establishe ...200515777007
genome size and organization in the blacklegged tick, ixodes scapularis and the southern cattle tick, boophilus microplus.genome sizes and the organization of repetitive dna were determined in the hard ticks ixodes scapularis and boophilus microplus using reassociation kinetics. the i. scapularis genome contains approximately 2.15 pg (2.1x10(3) mbp) of dna and consists of no foldback (fb), 27% highly repetitive (hr), 39% moderately repetitive (mr), and 34% unique dna. the b. microplus genome contains 7.5 pg (7.1x10(3) mbp) dna, and consists of 0.82% fb, 31% hr, 38% mr, and 30% unique dna. in both species, repetitiv ...200515796755
comparison of in vitro and in vivo ectoparasiticide activity of experimental benzimidazole-carbamate with permethrin and amitraz.a series of in vitro and in vivo bioassays were conducted to assess the ectoparasiticide activity of isopropyl-4-nitro-2,6-bis(trifluoromethyl)-1-benzimidazole-carbamate, an experimental benzimidazole-carbamate class compound. this compound was less potent than permethrin against ectoparasiticide-susceptible larvae of the lone star tick, amblyomma americanum (l.) (acari: ixodidae); larvae of the southern cattle tick, boophilus microplus (canestrini); and adult stable fly, stomoxys calcitrans (l. ...200515799532
boophilus microplus: the pattern of bovine immunoglobulin isotype responses to high and low tick infestations.cattle present variable levels of resistance to ticks and the immune correlates of these heritable phenotypes must be known in order to develop effective vaccines. the antibody responses to tick salivary antigens were examined in cattle of tick-susceptible (holstein) and tick-resistant (nelore) breeds. after heavy infestations, levels of igg1 and igg2 antibodies decreased in holsteins and remained the same in nelores. conversely, levels of ige antibodies increased in holsteins. different sizes o ...200515804374
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