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novel vaccines for ectoparasites.novel vaccines against ectoparasites have the potential to be cost-effective new technology for pest control that avoids some of the real and perceived problems with insecticide and acaricide usage. nevertheless, their development is in its infancy. a vaccine against the cattle tick boophilus microplus, the world's first vaccine against an ectoparasite, is in field use in australia. considerable effort had gone into the development of a vaccine against the sheep blowfly lucilia cuprina, while ot ...19979261979
comparison of indirect immunofluorescence (iif) and enzyme-linked immunosorbent assay (elisa) in detecting babesia bigemina infection in cattle.an indirect immunofluorescence test (iif) and an enzyme-linked immuno-sorbent assay (elisa) were standardised to investigate the prevalence of bovine babesiosis caused by babesia bigemina in experimentally and naturally infected bovids. both iif and elisa detected antibodies to b. bigemina 7 days after experimental infection with 87.5% and 100% sensitivity, respectively. the iif results indicated that a titre greater than 1:64 was a reliable indicator of b. bigemina infection. serological study ...19979270130
the application of moxidectin formulations for control of the cattle tick (boophilus microplus) under queensland field conditions.to assess the control of the cattle tick (boophilus microplus) and the performance of commercial cattle treated with the macrocylic lactone endectocide, moxidectin, formulated either as an injection or as a pour-on.19979293342
[serological study of rickettsia infections in niamey, niger].rickettsioses is a possible alternative to presumptive diagnosis of malaria. a serologic study was carried out in 1994 to determine the prevalence of rickettsioses in children under 5 years of age from three different areas of niamey, niger. indirect immunofluorescent assays using the micromethod were performed with antigens for rickettsia conori, rickettsia mooseri, and coxiella burneti. results were read from a positive threshold of 1/160 up to 1/640. out of a randomized population of 177 chil ...19979304008
rickettsiae-infected ticks in an endemic area of spotted fever in the state of minas gerais, brazil.a study on tick-borne rickettsiosis was developed in the county of santa cruz do escalvado, state of minas gerais, brazil, where a clinical case of the disease, confirmed by necropsy, had been reported. of the 1,254 ticks collected, 1,061 belonged to the amblyomma genus, 57 to the rhipicephalus sanguineus species, 81 to boophilus microplus, and 46 to anocentor nitens. the hemolymph test associated with giménez staining showed that 18 of the 221 a. cajennense specimens, 1 of the 16 r. sanguineus, ...19979361740
control of cattle ticks (boophilus microplus) on queensland dairy farms. 19979404613
babesiosis in china.the importance of babesiosis in livestock in china is discussed and mainly focused on bovine and equine babesiosis. babesiosis is still one of the most important diseases affecting livestock and has caused great economic loss. nine species of babesia have been recognized in livestock: b. bigemina, b. bovis, b. major, b. motasi, b. ovis, b. perroncitoi, b. trautmanni, b. equi (theileria equi), b. caballi. the distribution of babesia follows the distribution of the tick vectors. the main vectors o ...19979512738
babesiasis in nanjing area, china.this article discusses the tick-borne babesiases which harm dairy cattle, buffaloes and dogs. in addition, the pathogen, vector, seasonal occurrence, hosts, symptoms, pathological changes and treatment are summarized and analysed. the pathogens in this area were identified as babesia bigemina, b. bovis and b. gibsoni; the vectors as boophilus microplus, rhipicephalus haemaphysaloides, haemaphysalis longicornis. affected buffaloes were found from april to september, peak numbers occurred between ...19979512739
ticks and tick-borne bovine piroplasmosis in the southmountain pasture of hunan province, china.ticks and tick-borne bovine piroplasmosis is one of the most serious diseases affecting cattle bred in the southmountain pasture of hunan province. an investigation carried out from 1992 to 1995 showed that theileria sergenti was found in the blood of disease-stricken cows. ticks were collected from cattle. the species concerned (three genera and four species of ticks: haemaphysalis vietnamensis, haemaphysalis longicornis, ixodes sinensis and boophilus microplus) were identified by microscopy an ...19979512740
attempted transmission of babesia major by boophilus microplus.two experiments was carried out to determine if babesia major could be transmitted by boophilus microplus. in experiment 1, a babesia-free batch of laboratory reared bo. microplus larvae were applied to an intact calf infected by inoculation with a b. major stabilate. the calf showed a b. major parasitaemia while the larvae, nymphs and adult ticks were engorging. the engorged females were cultured and batches were incubated at one of the three following temperatures: 24, 28 or 32 degrees c. appr ...19979512741
large-scale production in pichia pastoris of the recombinant vaccine gavac against cattle tick.a gene coding for the bm86 tick protein was recently cloned, expressed in pichia pastoris and shown to induce an inmunological response in cattle against ticks. moreover, the gavac vaccine (heber biotec s.a., havana, cuba), which contains this recombinant protein, has proved to control the boophilus microplus populations under field conditions. this paper reviews the development and large-scale production of this vaccine, the efficacy of the resulting product and the strategy followed in designi ...19979141213
monoclonal antibodies against boophilus microplus and their effects on tick reproductive efficiency.four monoclonal antibodies (mabs) against extracts of embryo and gut tissue obtained from fully engorged boophilus microplus were produced. the mab brbml reacted with different instars and tissues, the brbm2 recognized only antigens present in gut extract and the mabs brbm3 and brbm4 recognized vitellin. the effect of inoculation of these mabs into fully engorged boophilus microplus females was also evaluated. the mabs brbm1 and brbm2 caused a decrease in oviposition of approximately 50% and 70% ...19979195739
epidemiological aspects of the brazilian spotted fever: seasonal activity of ticks collected in an endemic area in são paulo, brazil.ticks were collected from vegetation and animals at monthly intervals during one year (1993-1994) in an endemic area of brazilian spotted fever in the country of pedreira, state of são paulo. six species of ticks were identified amblyomma cajennense, amblyomma cooperi, amblyomma triste, anocentor nitens, rhipicephalus sanguineus and boophilus microplus. only the first species was sufficiently numerous to permit a quantitative study with seasonal activity, although the distribution and source of ...19979197151
different seasonal occurrence of anaplasmosis outbreaks in beef and diary cattle in an area of argentina free of boophilus microplus ticks.the seasonal occurrence of anaplasmosis (anaplasma marginale) outbreaks in dairy and beef cattle was analysed for a region of argentina (29 degrees to 31 degrees s and 58 degrees to 62 degrees w) that is free of boophilus microplus ticks, using data collected from december 1978 to november 1995. the outbreaks were confirmed by inspection of blood smears obtained from sick or dead cattle. a total of 94 outbreaks were confirmed by inspection of blood smears obtained from sick or dead cattle. a tot ...19979225428
[effect of digestion on the immunoglobulin g concentration in the intestinal contents of replete boophilus microplus females].in the present paper it was determined the concentration of immunoglobulin g in extracts from gut of female boophilus microplus engorded during the first 7 days of the second stage of continual digestion by using the simple radial immunodiffusion technique. it was also measured the concentration of hemoglobin by spectrophotometric methods. the analysis of correlation between both variables made during the study was positive and significant for p < 0.05. the analysis of simple variance and the ap ...19979685982
some quantitative aspects of natural babesial infection in the haemolymph of boophilus microplus engorged female ticks.quantitative aspects of the natural babesial (babesia bovis and babesia bigemina) infection in boophilus microplus engorged female ticks obtained from two herds of holstein heifers positive by the immunofluorescent antibody test to both protozoan were evaluated. the number of kinetes/microscope field of haemolymph was determined for each tick from day 5 to 10 post-collection. a close relationship between daily and cumulative babesial infection was detected. correlation and determination coeffici ...19979587602
establishment of boophilus microplus infected with babesia bigemina by using in vitro tube feeding technique.the in vitro tube feeding technique is used to establish a laboratory colony of boophilus microplus infected with babesia bigemina. pre-fed engorged female ticks offered 2 x 10(4) and 2 x 10(5)/ml of b. bigemina infected bovine red blood cells (rbc) showed sporokinetes in the haemolymph smear sample, and positive signals for b. bigemina in polymerase chain reaction (pcr). larvae laid from the ticks offered 2 x 10(5)/ml of b. bigemina infected rbc showed evidence for b. bigemina infection in micr ...19989592726
field studies and cost-effectiveness analysis of vaccination with gavac against the cattle tick boophilus microplus.the control of tick infestations and the transmission of tick-borne diseases remains a challenge for the cattle industry in tropical and subtropical areas of the world. traditional control methods have been only partially successful and the parasites continue to result in significant losses for the cattle industry. recently, vaccines containing the recombinant boophilus microplus gut antigen bm86 have been developed. these vaccines have been shown to control tick infestations in the field. howev ...19989607057
effect of particulation on the immunogenic and protective properties of the recombinant bm86 antigen expressed in pichia pastoris.the recombinant bm86 tick antigen expressed in pichia pastoris is obtained in a highly particulated form, as a distinguish feature of this expression system. this particulated protein, the active principle of the recombinant vaccine gavac against the cattle tick, have shown high immunogenic and protective properties, probably associated with its own characteristics. to evaluate the effects of particulation on the properties of bm86, three groups of calves were immunized with particulated or non- ...19989607058
isolation of an aspartic proteinase precursor from the egg of a hard tick, boophilus microplus.an aspartic proteinase precursor, herein named byc (boophilus yolk pro-cathepsin) was isolated from eggs of the hard tick, boophilus microplus. as judged by electrophoresis on sodium dodecyl sulfate polyacrylamide slab gel (sds-page), purified byc presented 2 bands of 54 and 49 kda, bearing the same nh2-terminal amino acid sequence. by western blot analysis, byc was also found in the haemolymph, indicating an extraovarian site of synthesis. several organs were incubated in culture medium with [3 ...19989651935
bovine babesiosis and anaplasmosis follow-up on cattle relocated in an endemic area for hemoparasitic diseases.a multiplex pcr/dna probe assay was used to monitor babesia bovis, b. bigemina and anaplasma marginale infection in cattle introduced to a boophilus microplus-infested area in veracruz, mexico. eight intact, 18-month-old, cross-bred beef cattle (four naive, group a; four babesia species--premunized, group b) were immediately exposed to ticks after arrival and were clinically monitored from day 6 to day 98 post-exposure (pe) to ticks. blood sample analysis for dna detection by the mpcr/dna probe ...19989668444
development of tick gut forms of babesia bigemina in vitro.development of a laboratory cultured tick-transmissible strain of babesia bigemina was followed in vitro after addition of gut material from engorged female boophilus microplus ticks and incubation at 37 degrees c. sequential development of stages, from intraerythrocytic strahlenkörper through multiplication to the fusion of what is assumed to be two gametes, is described. a change in physical environment (temperature, gas composition) experienced during passage of babesia stages into the in vit ...19989669864
adjuvant and immunostimulating properties of the recombinant bm86 protein expressed in pichia pastoris.the cattle tick boophilus microplus has remained a latent problem to the cattle industry. the recombinant vaccine gavac against the cattle tick has proved its efficacy and, conveniently, combined with the use of chemicals could be the solution to this problem. as this vaccine is based in the recombinant concealed antigen bm86, it has to be given periodically to the animal to maintain an adequate level of antibodies. some other commercially available vaccines for cattle also have to be given peri ...19989682358
epidemiology of tick-borne diseases of cattle in botshabelo and thaba nchu in the free state province.a seroepidemiological study was conducted on 151 cattle from the botshabelo and thaba nchu areas in the central free state province of south africa, two areas where small scale, peri-urban cattle farming is practised. an indirect fluorescent antibody test was used to test for babesia bigemina and b. bovis antibodies. to test for anaplasma marginale antibodies a competitive inhibition enzyme-linked immunosorbent assay method was used. there were no significant differences in serological test resu ...199810192841
production effects of cattle tick (boophilus microplus) infestation of high yielding dairy cows.forty mid-lactation holstein-friesian cows, 100% lot fed, were assigned to four groups for 15 weeks. two groups of 10 cows were infested each week with a gradually increasing number of boophilus microplus larvae, while the other two groups were maintained free of ticks. milk yield and composition (including somatic cell count, scc), liveweight, dry matter intake, packed cell volume (pcv) and total plasma protein (tpp) were measured throughout the 15 week period. by week 15, control cows produced ...19989703620
vaccination of cattle against the boophilus microplus using a mucin-like membrane glycoprotein.an antigen, bma7, which induced partial immunity against tick infestation has been isolated from boophilus microplus using two different protein fractionation protocols, accompanied by vaccination and parasite challenge trails. the antigen is a 63 kda glycoprotein isolated from semi-engorged adult female ticks. though significant, the induced immunity is less striking than that previously reported for antigen bm86 from the same parasite. however, co-vaccination with bm86 and bma7 can enhance imm ...19989717194
a survey of the ixodid ticks parasitising cattle in the eastern province of zambia.the results of tick surveys carried out in the eastern province of zambia between december 1982 and february 1996 were principally in agreement with the findings of earlier surveys conducted during the period 1965-72. boophilus decoloratus has almost been replaced by boophilus microplus. hyalomma truncatum was found in small numbers throughout the province and hyalomma marginatum rufipes was only rarely encountered in collections made from cattle. rhipicephalus evertsi evertsi was largely confin ...19989737594
acetylcholinesterase cdna of the cattle tick, boophilus microplus: characterisation and role in organophosphate resistance.acetylcholinesterase is the target of organophosphate and carbamate pesticides. organophosphate resistance is widespread in the cattle tick, boophilus microplus, in australia. we have isolated a cdna of acetylcholinesterase from b. microplus and show that it would encode a protein 62 kda in size. the predicted amino acid sequence contains all the residues characteristic of an acetylcholinesterase. alternative splicing of the transcript was detected at both the 5' and 3' ends. alternative splicin ...19989753768
comparison of effects of low and high tick infestations on acquired cattle tick resistance: hyalomma marginatum marginatum.three holstein calves were infested with low numbers of ticks, two or three pairs of adults hyalomma marginatum marginatum in cloth bag daily for 21 days. infestation was carried out during tick proliferation periods. two months later, cattle leads were challenged with 100 pairs of ticks. another group of three holstein calves were infested five times with 100 pairs of adult ticks of the same species. the five infestations were performed two weeks from the previous infestation. three tick charac ...19989754299
use of a mathematical model to study the control measures of the cattle tick boophilus microplus population in new caledonia.boophilus microplus is a common cattle tick of great economic importance in various tropical and subtropical countries like new caledonia. the proposed model describes the population dynamics of female boophilus microplus in the absence of resistant ticks. it is a system of six difference equations which can be mathematically analyzed. the analysis of the system shows the great importance of the eigenvalue denoted by lambda1. the population of ticks increases if lambda1 < 1 and decreases if lamb ...19989763318
studies on the effect of infection by babesia sp. on oviposition of boophilus microplus engorged females naturally infected in the mexican tropics.three hundred and fifteen engorged female boophilus microplus ticks (weight 210-250 mg) naturally infected with babesia sp., in the mexican tropics were monitored for egg production. haemolymph samples were taken from each tick on the 5th day to the 16th day after collection to detect and estimate the infection with babesia sp. kinetes. all ticks were held in darkness at 27+/-1.5 degrees c and 85-86% relative humidity. the infection rate of babesia sp. was 20.3% (64/315). fifteen ticks were cons ...19989786625
variation in n-linked oligosaccharide structures on heterologous proteins secreted by the methylotrophic yeast pichia pastoris.we report the characterization of n-linked oligosaccharides on six foreign glycoproteins secreted from the methylotrophic yeast pichia pastoris. these proteins included: a bacterial enzyme, bacillus licheniformis alpha-amylase; three fungal enzymes, saccharomyces cerevisiae invertase, penicillium minioluteum dextranase, and mucor pusillus aspartic protease; and two higher eukaryotic proteins, boophilus microplus (tick) gut antigen and bovine enterokinase catalytic subunit. the carbohydrates on t ...19989790882
distinguishing species and populations of rhipicephaline ticks with its 2 ribosomal rna.most populations and some species of ticks of the genera boophilus (5 spp.) and rhipicephalus (ca. 75 spp.) cannot be distinguished phenotypically. moreover, there is doubt about the validity of species in these genera. i studied the entire second internal transcribed spacer (its 2) rrna of 16 populations of rhipicephaline ticks to address these problems: boophilus microplus from australia, kenya, south africa and brazil (4 populations); boophilus decoloratus from kenya; rhipicephalus appendicul ...19989794625
pcr-ribotyping of xenorhabdus and photorhabdus isolates from the caribbean region in relation to the taxonomy and geographic distribution of their nematode hosts.the genetic diversity of symbiotic xenorhabdus and photorhabdus bacteria associated with entomopathogenic nematodes was examined by a restriction fragment length polymorphism analysis of pcr-amplified 16s rrna genes (rdnas). a total of 117 strains were studied, most of which were isolated from the caribbean basin after an exhaustive soil sampling. the collection consisted of 77 isolates recovered from entomopathogenic nematodes in 14 caribbean islands and of 40 reference strains belonging to xen ...19989797272
effect of antibodies against beta-n-acetylhexosaminidase on reproductive efficiency of the bovine tick boophilus microplus.a polyclonal antibody (anti-hex) was developed against a soluble n-acetylhexosaminidase (hex) isolated from larval extracts of boophilus microplus. purified hexosaminidase was strongly inhibited by the igg fraction of this antibody. the antibody inhibited the hexosaminidase activity of other sources, such as haemolymph and larval membranes. the antibody reacted with different antigens in the tick haemolymph, but did not recognize any antigen in saliva, as seen by immunoblot analysis. the anti-he ...19989823065
in vitro and in vivo evaluations of a strain of boophilus microplus (acari: ixodidae) selected for resistance to permethrin.a strain of boophilus microplus (canestrini) was selected fro resistance to permethrin by pressuring larvae with increasing doses (range, 0.05-0.35% [ai]) through successive generations (generations f2-f7). at the beginning of the selection process (f2), the pyrethroid resistant (pr) strain was 5.4 times more resistant to permethrin than the pyrethroid susceptible (ps) strain, and the level of resistance increased in each successive generation of the pr strain, reaching a resistance factor (resi ...19989835695
contact chemostimuli in the mating behaviour of the cattle tick, boophilus microplus.mating of the cattle tick boophilus microplus is mediated by chemical stimuli on the cuticle of females. males are arrested on the dorsum of females attached to the host, frequently sample the substrate, and then tip-over to the ventrally located gonopore. these behaviours are also observed in vitro when males are placed on a small glass bead treated with a female extract. time spent and tip-over by male ticks on dummies is used in an assay to test the behavioural significance of fractions of th ...19989846376
attitudes and practices of queensland dairy farmers to the control of the cattle tick, boophilus microplus.to determine practices for the control of cattle ticks on dairy farms in queensland, the attitudes of farmers to tick infestations and to identify opportunities for and barriers against the introduction of non-chemical methods of tick control.19989862066
efficacy of amitraz (taktic 12.5% ec) as a dip for the control of boophilus microplus (canestrini) (acari: ixodidae) on cattle.four groups of cattle infested with boophilus microplus (canestrini) were each dipped in a different concentration of amitraz diluted from a 12.5% ec formulation to determine the efficacy and performance of the product in an 11,400 l dipping vat. except for the period when heifers were dipped, animals were restrained in stanchions placed individually inside 3.3 x 3.3 m2 stalls within an open-sided barn. the amitraz in the vat was stabilized with hydrated lime to maintain a ph of ca. 12. analyses ...19989879580
immunization of bovines with an aspartic proteinase precursor isolated from boophilus microplus eggs.the capacity of the boophilus yolk pro-cathepsin (byc) to induce a protective immune response in cattle against boophilus microplus infestation was tested by vaccination experiments and by inoculation of monoclonal antibody (mab) against byc into fully engorged tick females. in immunization experiments the measurement of various biological parameters demonstrated a partial protection against b. microplus. a continuous decrease in the levels of specific antibodies was observed over 11 months when ...19989880109
levels of natural resistance to boophilus microplus (acari: ixodidae) in carora breed bulls.boophilus microplus infestation is one of the most serious limitations to cattle industry in tropical regions, even though bovines show natural resistance to ticks. this resistance was evaluated in cross-bred carora bulls (ccb) a tropicalized dairy breed from venezuela. seven ccb were experimentally infested with b. microplus larvae, "mozo" strain, they were considered tick-naive because they had never been infested with ticks. the mean inoculum size applied on each bull was 6,477 larvae. after ...199810347818
expressed sequenced tags and new genes from the cattle tick, boophilus microplus.we used the expressed sequenced tags (ests) approach to study the genome of the cattle tick boophilus microplus. one hundred and forty-two of our 234 unique ests were from genes not previously identified from ticks, mites or any other arachnids. the largest class of identified ests (29%) was from genes involved in transcription and translation. ninety-one ests (39% of all ests) did not match any sequences in international databases; some of these may be specific to ticks. thirteen percent of our ...19989519466
[imported arthropod-borne parasites and parasitic arthropods in dogs. species spectrum and epidemiologic analysis of the cases diagnosed in 1995/96].between january 1995 and december 1996 nonendemic or only regionally occurring arthropodborne parasites including ehrlichiae and parasitic arthropods in germany were detected in 484 dogs, whereby at least 15 species were involved. listed in decreasing order, leishmania infections occurred most frequently, followed by infections/infestations with babesia canis, ehrlichia canis, rhipicephalus sanguineus, dirofilaria immitis and dermacentor reticulatus. the other species, namely babesia gibsoni, tr ...19989531673
therapeutic and persistent efficacy of fipronil against boophilus microplus (acari: ixodidae) on cattle.cattle infested with all parasitic life-stages of boophilus microplus (canestrini) were treated once with a pour-on formulation of fipronil at 0.25, 0.5, or 1.0% active ingredient (ai) to determine the therapeutic efficacy. additionally, cattle were infested at weekly intervals for 13 consecutive weeks after treatment to determine the persistent effectiveness of the three concentrations. results of therapeutic efficacy of fipronil showed that with each increase in concentration there was a corre ...19989561711
sporogony and experimental transmission of babesia equi by boophilus microplus.the development of babesia equi in salivary glands of adult female boophilus microplus was observed under a light microscope using semithin sections stained with toluidine blue. engorged nymphs were obtained from splenectomized foals experimentally infected with b. equi. as adults, they were then fed on rabbits for 5 days and the salivary glands of manually collected individuals were removed at intervals of 24 h. sporozoites were found in type iii granular acini cells between the 2nd and 5th day ...19989580425
eradication and pest management.eradication is the elimination of every single individual of a species from an area to which recolonization is unlikely to occur. cost-benefit analyses of eradication programs involve biases that tend to underestimate the costs and overestimate the benefits. in this review, we (a) highlight limitations of current cost-benefit analyses, (b) assess eradication strategies from biological and sociological perspectives by discussing particular cases of successful and failed eradication efforts, and ( ...19989444755
ultrastructure of sporogony in babesia equi in salivary glands of adult female boophilus microplus ticks.the development of babesia equi was studied in the salivary glands of adult female ticks, boophilus microplus, using a transmission electron microscope (tem). engorged nymphs were obtained from splenectomized foals experimentally infected with b. equi and fed in the adult phase for 5 days on rabbits. sporogony in b. equi involves the development of sporoblasts and sporozoites, which form from finger-like projections on the surface and through radial budding. mature sporozoites (2.0 x 1.1 microns ...19989491430
daily mean number of eggs laid by the southern cattle tick (acari: ixodidae) compared with mean egg mass weight.among several methods used to estimate the efficacy of an acaricide is the drummond adult test, based on formulas which permit the assessment of the reproductive capacity of treated female ticks in comparison with controls. a constant value of 20,000 is normally used in these formulas, because this figure approximates the number of larvae that will hatch from 1 g of eggs. in laboratory studies conducted on large numbers of ticks, egg counting is a time-consuming and fastidious operation. therefo ...19989495089
effects of metarhizium anisopliae on the tick boophilus microplus (acari: ixodidae) in stabled cattle. 19989500942
detection of cattle naturally infected with anaplasma marginale in a region of endemicity by nested pcr and a competitive enzyme-linked immunosorbent assay using recombinant major surface protein 5.a competitive enzyme-linked immunosorbent assay using recombinant major surface protein 5 (rmsp5-celisa) of anaplasma marginale was validated in a naturally infected cattle herd in an area of eastern oregon where a. marginale is endemic. the true positive and negative a. marginale infection status of 235 randomly selected cattle was determined by using a nested pcr (npcr) coupled with msp5 sequence analysis and hybridization. judgment of the reliability of the npcr and hybridization for detectio ...19989508311
comparison of genomic dna in various strains of boophilus microplus (acari: ixodidae).the conventional method of identifying acaricide resistance in a suspect tick population by the united nations food and agriculture organization packet assay is a laborious and time-consuming process. dna probes have been demonstrated as rapid and accurate tools for detecting pesticide resistance in insect species. random-amplified polymorphic dna (rapd) has been used by other groups to differentiate species of mosquitoes and populations within a mosquito species. by using different arbitrary ol ...19989775626
regionalization of oviducts in boophilus microplus (canestrini, 1887) (acari: ixodidae) and its potential significance for fertilization.the structural analysis of oviducts in boophilus microplus (canestrini, 1887) in different stages of ingurgitation has indicated that they are constituted primarily of an internal cylinder and an external cylinder with different cell types being found between them. copulated females in active ingurgitation process show typical variations along the internal cylinder, and three regions can be defined: anterior, ring-like and transitional. based on such regionalization, hypotheses were raised about ...199923505653
immunology of the tick-host interaction and the control of ticks and tick-borne diseases.the first experimental vaccination against ticks was carried out 60 years ago. since then, progress has been slow, although the recent commercial release of a recombinant vaccine against boophilus microplus is significant. the nature of naturally acquired protective immunity against ticks is poorly understood, particularly in the important, domesticated ruminant hosts. characterization of the antigens of naturally acquired immunity remains limited, although more has been achieved with 'concealed ...199910377526
anti-tick effects of stylosanthes humilis and stylosanthes hamata on plots experimentally infested with boophilus microplus larvae in morelos, mexico.the anti-tick effects of the tropical pasture legumes stylosanthes humilis and stylosanthes hamata were evaluated and compared with two common grasses, cenchurus ciliaris and andropogon gayanus, in the state of morelos, mexico, on plots experimentally infested with larvae of the tick boophilus microplus. the effect was evaluated by recovery of larvae from the experimental plots by flagging during a 4 week period. the anti-tick effect due to stylosanthes was significantly higher for s. humilis an ...199910356768
the novel mitochondrial gene arrangement of the cattle tick, boophilus microplus: fivefold tandem repetition of a coding region.we sequenced across all of the gene boundaries in the mitochondrial genome of the cattle tick, boophilus microplus, to determine the arrangement of its genes. the mtdna of b. microplus has a coding region, composed of trna(glu) and 60 bp of the 3' end of nd1, that is repeated five times. boophilus microplus is the first coelomate animal known to have more than two copies of a coding sequence. the mitochondrial genome of b. microplus has other unusual features, including (1) reduced t arms in trn ...199910368952
serologic cross-reactivity of antibodies against borrelia theileri, borrelia burgdorferi, and borrelia coriaceae in cattle.to evaluate the immune response induced by borrelia theileri infection and to determine whether b theileri induces cross-reacting antibodies to other bovine borreliae.199910376894
ixodid ticks avoid contact with liquid water.larvae of the cattle tick boophilus microplus and all life stages of the european sheep tick ixodes ricinus avoid walking on a wet membrane surface surrounding a dry patch. of 170 reactions made at a border with liquid water by 22 b. microplus larvae, 40% consisted of immediate turns to the opposite side to bring all the legs back onto a dry patch, 41% were walks along the border, during which the ticks maintained contact with both the dry and wet zones, and 19% were returns to the dry patch aft ...199910377269
cloning and expression of ecto 5-nucleotidase from the cattle tick boophilus microplus.although 5'-nucleotidases are ubiquitous in higher vertebrates, the arthropod enzymes have been little studied. the cdna sequence of the mature 5'-nucleotidase from the tick boophilus microplus was therefore determined (genbank accession number: u80634). the enzyme has 39-41% sequence identity with the vertebrate 5'-nucleotidases and contains binuclear metal ion binding sites. there are no significant introns within the coding region of the genomic sequence. southern blot analysis indicates the ...199910380109
isolation of a cdna for an octopamine-like, g-protein coupled receptor from the cattle tick, boophilus microplus.octopamine is a biogenic amine neurotransmitter of invertebrates that binds to a g-protein coupled receptor that has seven transmembrane domains. formamidine pesticides like amitraz are highly specific agonists of the octopamine receptor. amitraz is used extensively to control the cattle tick, boophilus microplus, and many other ticks but now there are strains of ticks that are resistant to amitraz. we have isolated a cdna from the cattle tick, b. microplus, that belongs to the biogenic amine fa ...199910380658
arthropod parasites of nubian ibexes (capra ibex nubiana) and gazelles (gazella gazella) in israel.in a 20-year survey the following ectoparasites were collected from nubian ibexes: larvae of an unidentified oestrus sp. collected from the nasal cavities, sinuses and horns, hippoboscid flies (lipoptena chalcomelaena) specific to the nubian ibex, blood sucking lice (linognathus africanus) and unidentified biting lice (damalinia sp.). ibexes were severely infested with the cattle tick, boophilus annulatus; a few hyalomma anatolicum excavatum ticks were also collected. in five ibexes kept in two ...199910392972
a missing metabolic pathway in the cattle tick boophilus microplus.heme proteins are involved in a wide variety of biological reactions, including respiration, oxygen transport and oxygen metabolism [1]. the heme prosthetic group is synthesized in almost all living organisms except for a few pathogenic bacteria and trypanosomatids that use blood as food [2] [3]. there is a general belief that all nucleated animal cells synthesize heme [1] [4]. however, blood-feeding arthropods ingest enormous amounts of vertebrate blood in a single meal and the heme pathway has ...199910395540
control of boophilus microplus ticks in cattle calves by immunization with a recombinant bm86 glucoprotein antigen preparation.forty egyptian native cattle calves of 4-6 months old randomly allocated into two groups of twenty animals each were used to assess the effect of immunization of animals with a recombinant bm86 antigen derived from boophilus microplus ticks on induction of immunity that could protect calves during tick season. the immunization protocol involved two injections administered intramuscularly, the first was applied with complete freund's adjuvant and the second was given with incomplete freund's adju ...199910422372
purification and characterization of beta-n-acetylhexosaminidase from bovine tick boophilus microplus (ixodide) larvae.beta-n-acetylhexosaminidase (hex, e.c. 3.2.1.52) from larvae of the ixodid tick boophilus microplus was purified to capillary zone electrophoresis homogeneity, and characterized. enzyme purification was carried out by sequential liquid chromatography on sephadex g-200, p-aminobenzyl-n-acetyl-beta-d-thioglucosamine affinity, and mono-q fplc columns. purification was about 1600-fold, with a yield of 10%, as determined with p-nitrophenyl-n-acetylglucosaminide as substrate. the enzyme presented opti ...199910425723
identification of a point mutation in the para-type sodium channel gene from a pyrethroid-resistant cattle tick.to investigate the molecular mechanism of resistance to pyrethroids in the southern cattle tick, boophilus microplus, we have obtained and sequenced a partial para-homologous sodium channel cdna from susceptible and pyrethroid-resistant tick strains. a point mutation that results in an amino acid change from phe to ile was identified in the highly conserved domain iiis6 of the homologous sodium channel from ticks that are highly resistant to pyrethroid acaricides. this mutation is at a location ...199910441465
seroepidemiologic studies on babesia equi and babesia caballi infections in brazil.horses from six stud farms representing the most frequent types of horse breeding in brazil were tested for babesia antibodies by the ifa test. the farms are located at the tropic of capricorn at an altitude of 472-715 m where temperatures below 0 degrees c may occur. horses of conventional stud farms were infested with dermacentor nitens, amblyomma cajennense, and boophilus microplus. infestation with bo. microplus was associated with direct or indirect contact of horses with cattle, and was no ...199910447188
recent advances in determining the pathogenesis of canine monocytic ehrlichiosis. 199910449445
host-odour recognition in two tick species is coded in a blend of vertebrate volatiles.the questing behaviour of ixodid ticks serves for identification and localisation of approaching hosts and is evoked by carbon dioxide, vibrations, visual and odour stimuli. in an olfactometer, we examined the specificity of the questing response of larvae of boophilus microplus, a one-host tick which develops mainly on cattle, and ixodes ricinus, a three-host tick with a broader host spectrum. while all mammalian odours tested were equally stimulatory for i. ricinus, b. microplus was clearly mo ...199910450611
effect of breed of cattle on transmission rate and innate resistance to infection with babesia bovis and b bigemina transmitted by boophilus microplus.to assess the effect of breed of cattle on the transmission rates of and innate resistance to babesia bovis and b bigemina parasites transmitted by boophilus microplus ticks.199910451733
characterization and molecular cloning of a glutathione s-transferase gene from the tick, boophilus microplus (acari: ixodidae).a glutathione s-transferase (gst) was purified from the larval cattle tick, boophilus microplus (acari: ixodidae), by glutathione-affinity chromatography. the purified enzyme appeared as a single band on sds-page and has a molecular mass of 25.8 kda determined by mass spectrometry. the n-terminus of the purified enzyme was sequenced. the full-length cdna of the enzyme was isolated by rt-pcr using degenerate oligonucleotides derived from the n-terminal amino acid sequence. the cdna contains an op ...199910451925
antimicrobial activity of a bovine hemoglobin fragment in the tick boophilus microplus.antifungal and antibacterial activities were detected in the hemolymph and gut contents of the cattle tick, boophilus microplus. a peptide with antibacterial activity from the tick gut contents was purified to homogeneity by reversed-phase chromatography. the molecular mass of the purified peptide was 3,205.7 da, measured by matrix-assisted laser desorption/ionization mass spectrometry. the amino acid sequence was obtained by edman degradation and showed that the peptide was identical to a fragm ...199910464258
human otoacariasis.accidental entry of insects and other arthropods is a common aetiology of aural foreign bodies (fb) presenting to accident and emergency departments. a retrospective study revealed that the fb in almost half (148) of 348 cases of aural fb investigated at the universiti sains malaysia hospital was an arthropod. the most common arthropod encountered was the cockroach, followed by a cattle tick. the high prevalence of tick infestation of the human ear canal (i.e. human otoacariasis) currently appea ...199910474641
lack of immunological cross-reactivity of 36-kda secretory salivary gland antigen of hyalomma anatolicum anatolicum with hyalomma dromedarii and boophilus microplus ticks.during feeding of ticks of the species hyalomma anatolicum anatolicum, most of the proteins in salivary gland extracts (sges) remained unchanged from the unfed to the fully fed state (from day 1 to day 7 of the experiment), as revealed by sds-page. however, a 45-kda protein band disappeared and 26-, 32- and 33-kda bands appeared when feeding commenced. some of the protein bands changed their intensity. when probed with anti-h. anatolicum anatolicum hyperimmune sera, transblotted sge proteins of ...199910481624
the effect of rangeland fires on cattle tick infestation in western zambia. 199910509420
a new family of cytochrome p450 genes (cyp41) from the cattle tick, boophilus microplus.we isolated and sequenced a cytochrome p450 (cyp) gene that is sufficiently different from other cyp genes that a new cyp family, cyp41 was created. cyp41 encodes a protein of 518 residues and is most similar to genes from the family cyp3; it is 36% identical to cyp3a2 and 34% identical to cyp3a28. we hypothesise that cyp41 encodes an enzyme that metabolizes xenobiotic compounds i.e. compounds that are foreign to the cattle tick. the phylogenetic position of cyp41 could not be resolved because o ...199910510501
[african rickettsia infections].epidemiology: african rickettsiasis is transmitted by rickettsia africae, a cattle tick. amblyomma spp. is an emerging rickettsiasis in sub-sehalian afric described in 1992. seroepidemiology studies conducted in africa show that it is probably the most widespread rickettsiasis in the sorld. in addition, the development of tourist activities in southern african countries has led to an increase in the number of reported cases in subjects returning from endemic areas. a high serprevalence of anti r ...199910518970
characterization of pyrethroid resistance and susceptibility to coumaphos in mexican boophilus microplus (acari: ixodidae).two patterns of pyrethroid resistance were characterized from boophilus microplus (canestrini) collected in mexico. one was characteristic of a kdr mutation and the other involved esterase and cytochrome p450 enzyme systems. very high resistance to permethrin, cypermethrin, and flumethrin, not synergized by tpp and pbo and high resistance to ddt, characterized the kdr-like pattern found in the corrales and san felipe strains. esterase and cytochrome p450-dependent resistance was found in the coa ...199910534945
sequence analysis of the knockdown resistance-homologous region of the para-type sodium channel gene from pyrethroid-resistant boophilus microplus (acari: ixodidae).using reverse transcription polymerase chain reaction and degenerate oligonucleotide primers, a partial para-homologous sodium channel cdna was obtained from the southern cattle tick, boophilus microplus (canestrini). the cdna sequence encoded the region in which knockdown resistance (kdr)-type mutations have been identified in numerous insect species. comparison of deduced amino acids from the cdna sequence showed high similarity with sodium channels from other species, particularly in highly c ...199910534946
integrated control of acaricide-resistant boophilus microplus populations on grazing cattle in mexico using vaccination with gavac and amidine treatments.throughout most of the twentieth century, tick infestations on cattle have been controlled with chemical acaricides, typically administered by dipping or spraying. this approach can cause environmental and residue problems and has created a high incidence of acaricide resistance within tick populations in the field. recently we developed a vaccine against boophilus microplus employing a recombinant bm86 antigen preparation (gavac), (heber biotec s.a., havana, cuba) which has been shown to induce ...199910581714
control of boophilus annulatus (acari: ixodidae) on cattle using injectable microspheres containing ivermectin.the efficacy of an injectable microsphere formulation of ivermectin for control of the cattle tick, boophilus annulatus (say), was tested on 2 groups of 6 hereford heifers held on separate 7-ha, tick-infested, buffel grass pastures. cattle in one pasture were injected subcutaneously in the neck with a controlled-release microsphere formulation of ivermectin at the rate of 2.4 mg ai/kg body weight; the other group was injected with carrier only. beginning 4 wk after injection and continuing throu ...199910582049
bm86 antigen induces a protective immune response against boophilus microplus following dna and protein vaccination in sheep.vaccination of sheep with a plasmid bearing the full length gene for the tick antigen bm86 either alone or co-administered with plasmid carrying the ovine genes for the cytokines, granulocyte and macrophage colony stimulating factor (gm-csf) or interleukin (il)-1beta induced a relatively low level of protection against subsequent tick infestation. this tick damage reached statistical significance only for the groups which were vaccinated with plasmid encoding for bm86, co-administered with plasm ...199910587297
transmission of babesia spp by the cattle tick (boophilus microplus) to cattle treated with injectable or pour-on formulations of ivermectin and moxidectin.to assess the efficacy of ivermectin and moxidectin to prevent transmission of babesia bovis and babesia bigemina by boophilus microplus to cattle under conditions of relatively intense experimental challenge.199910590793
cloning and sequencing of a putative acetylcholinesterase cdna from boophilus microplus (acari: ixodidae).using a strategy based on degenerate primers derived from acetylcholinesterase (ache) from other species, we cloned and sequenced a putative ache cdna from the southern cattle tick, boophilus microplus (canestrini). the sequence has a high degree of homology to sequences of ache from other species reported in the genbank. the open reading frame of 1,689 bp, corresponding to a deduced sequence of 563 amino acids, has conserved regions and features shared by the ache family, necessary for its cata ...199910593078
immunological control of ectoparasites: past achievements and future research priorities.recombinant vaccines are available for the control of the tick boophilus microplus, while progress has been made in the development of vaccines against lucilia cuprina and chrysomya bezziana. literature suggests that the control of other ectoparasites is feasible, either through the duplication in a vaccine of naturally acquired immunity or through 'concealed' antigen vaccines. major deficiencies in our current knowledge however point to possible research opportunities for the future. the identi ...199910596752
a double headed serine proteinase inhibitor--human plasma kallikrein and elastase inhibitor--from boophilus microplus larvae.preying on cattle, the hard tick boophilus microplus causes heavy economical losses to brazil. tick proteins are a good target to be used as tools for tick control. serine protease inhibitors from b. microplus larvae (bmti) were preliminarily characterized. one-week-old larvae were the source of a 2% protein solution in 5 mm tris-hcl, 20 mm nacl, ph 7.4. the inhibitors were purified by affinity chromatography on trypsin-sepharose, and ion-exchange chromatography on resource q column, and they se ...199910615008
comparison of acetylcholinesterase genes from cattle ticks.we describe the isolation and characterisation of two putatively new acetylcholinesterase genes from the african cattle ticks boophilus decoloratus and rhipicephalus appendiculatus. the nucleotide sequences of these genes had 93% homology to each other and 95% and 91% identity, respectively, to the acetylcholinesterase gene from an australian strain of another cattle tick, boophilus microplus. translation of the nucleotide sequences revealed putative amino acids that are essential for acetylchol ...199910616922
geostatistics and remote sensing using noaa-avhrr satellite imagery as predictive tools in tick distribution and habitat suitability estimations for boophilus microplus (acari: ixodidae) in south america. national oceanographic and atmosphere administration-advanced very high resolution radiometer.remote sensing based on noaa (national oceanographic and atmosphere administration) satellite imagery was used, together with geostatistics (cokriging) to model the correlation between the temperature and vegetation variables and the distribution of the cattle tick, boophilus microplus (canestrini), in the neotropical region. the results were used to map the b. microplus habitat suitability on a continental scale. a database of b. microplus capture localities was used, which was tabulated with t ...19999950331
a simulation study of the effects of acaricides and vaccination on boophilus cattle-tick populations.this paper describes a simulation model to evaluate different control strategies for boophilus microplus. the model combines a dynamic life-history module for tick-population dynamics with other modules for vaccination, sterile-hybrid larval release and use of acaricide dipping vats. the tick life-history module considers the cattle's nutritional level and allows for distribution of ticks by age at all stages of growth. appropriately, the model was sensitive to host resistance and to host-nutrit ...199910022052
towards a permanent solution for controlling cattle ticks.acaricides are essential in the short-term but do not offer a permanent solution to tick control. this situation will not change without a change of approach. a vaccine against boophilus microplus confers partial long-term control but has little immediate effect on tick burdens. the effectiveness of acaricides and vaccination is greatest for breeds of high tick resistance. high host resistance is the key to effective long-term tick control with total resistance the ultimate aim. while improvemen ...199910048820
molecular characterization of a haemaphysalis longicornis tick salivary gland-associated 29-kilodalton protein and its effect as a vaccine against tick infestation in rabbits.the use of tick vaccines in mammalian hosts has been shown to be the most promising alternative tick control method to current use of acaricides, which suffers from a number of limitations. however, the success of this method is dependent on the identification, cloning, and in vitro expression of tick molecules involved in the mediation of key physiological roles with respect to the biological success of a tick as a vector and pest. we have sequenced and characterized a haemaphysalis longicornis ...199910084999
detection of igm antibodies against babesia bovis in cattle.the diagnosis of acute babesiosis by direct examination of blood smears has some limitations and the indirect serological methods currently in use are designed for detection of igg, which may not be detectable at an early stage of infection. there is a need, therefore, for rapid and reliable procedures to diagnose acute infections. an elisa system using a crude antigenic preparation of babesia bovis was standardized for the detection of igm antibodies. optimal dilutions of the antigen, using pos ...199910223346
successive tick infestations selectively promote a t-helper 2 cytokine profile in mice.several studies have revealed that t lymphocytes and cytokines play a crucial role in determining the outcome of parasitic infections in terms of protective immunity. in this study we found that rhipicephalus sanguineus tick saliva stimulates transforming growth factor-beta (tgf-beta), and reduces interleukin-12 (il-12) secretion by cells from normal c3h/hej mice. moreover, murine lymph node cells harvested 6 days after the fourth infestation with ticks presented an 82.4% decrease in their proli ...199910233725
identification and characterisation of a cytochrome p450 gene and processed pseudogene from an arachnid: the cattle tick, boophilus microplus.we isolated and sequenced the first known cytochrome p450 gene and pseudogene from an arachnid, the cattle tick, boophilus microplus. both the gene and pseudogene belong to the family cyp4, but a new subfamily, cyp4w, had to be created for these genes because they are substantially different to other cyp4 genes. the gene, cyp4w1, has greatest homology with cyp4c1 from a cockroach, blaberus discoidalis. the predicted molecular weight of the protein encoded by cyp4w1 (63 kda) is greater than that ...199910333575
access of antibody or trypsin to an integral outer membrane protein (p66) of borrelia burgdorferi is hindered by osp lipoproteins.the outer membrane of borrelia burgdorferi, the lyme disease agent, contains lipoproteins anchored by their lipid moieties and integral proteins with membrane-spanning regions. we used the techniques of in situ proteolysis, immunofluorescence, in vitro growth inhibition, and cross-linking with formaldehyde to characterize topological relationships between p66, an integral membrane protein, and selected osp lipoproteins of b. burgdorferi. protease treatment of intact spirochetes cleaved p66 and o ...199910338494
detection of genomic variability in different populations of the cattle tick boophilus microplus in southern brazil.dna from seven isolates of the cattle tick boophilus microplus was analyzed by restriction fragment length polymorphism (rflp). three different cdna clones, named p-9, p-25 and cp-12, isolated from a b. microplus cdna library, were used as dna probes. dna sequences of p-9 have high similarity to ribosomal genes, whereas p-25 does not show significant homology with known sequences within databases. cp-12 is a cdna clone encoding a cysteine endopeptidase gene. a limited degree of polymorphism was ...199910628703
efficacy of coumaphos applied as a dip for control of an organophosphorus-resistant strain of boophilus microplus (acari: ixodidae) on cattle.the efficacy of coumaphos, an organophosphorus acaricide, was tested on a strain of boophilus microplus (canestrini) that was 9.5 times more resistant to the chemical than a susceptible strain. cattle infested with larval, nymphal, and adult ticks were dipped into a vat charged at concentrations of 0.031, 0.083, 0.160, and 0.279% (ai). assessment of efficacy was based on surviving tick numbers, female weight, egg mass weight, egg hatchability, and index of reproduction. at 0.031% (ai), the level ...199910633578
sequence variations in the boophilus microplus bm86 locus and implications for immunoprotection in cattle vaccinated with this antigen.cattle tick infestations constitute a major problem for the cattle industry in tropical and subtropical regions of the world. traditional control methods have been only partially successful, hampered by the selection of chemical-resistant tick populations. the boophilus microplus bm86 protein was isolated from tick gut epithelial cells and shown to induce a protective response against tick infestations in vaccinated cattle. vaccine preparations including the recombinant bm86 are used to control ...199910668863
monooxygenases play only a minor role in resistance to synthetic pyrethroids in the cattle tick, boophilus microplus.we investigated the role of monooxygenases in resistance to synthetic pyrethroids (sps) in the cattle tick, boophilus microplus. we found that monooxygenases play only a minor role in resistance to sps in both resistant and susceptible strains of b. microplus. we blocked the monooxygenases with piperonyl butoxide (pbo) and simultaneously applied the sps, flumethrin and cypermethrin to larval b. microplus. pbo increased the effect of flumethrin (synergism ratios 2.7-8.9) more than it increased th ...199910668864
detecting resistance to organophosphates and carbamates in the cattle tick boophilus microplus, with a propoxur-based biochemical test.rapid and sensitive detection of resistance to insecticides in arthropods is needed. in the cattle tick. boophilus microplus, resistance to a variety of acaricides is widespread. the most commonly used assay for resistance, the larval packet test, takes at least two, but generally six weeks for a one-host tick like b. microplus to complete and may take up to three months to complete for three-host ticks. here we describe a test for resistance to organophosphate acaricides that can be used on lar ...199910668865
ticks of south carolina (acari: ixodoidea).county and host records are reported for 19 species of ticks from south carolina: amblyomma americanum, amblyomma maculatum, amblyomma tuberculatum, aponomma latum, boophilus annulatus, boophilus microplus, dermacentor albipictus, dermacentor variablis, haemaphysalis leporispalustris, ixodes affinis, ixodes brunneus, ixodes cookei, ixodes marxi, ixodes minor, ixodes scapularis, ixodes texanus, ixodes woodi, rhipicephalus sanguineus, and ornithodoros capensis. ixodes woodi is recorded from south ...199910672552
effect of breed of cattle on innate resistance to infection with anaplasma marginale transmitted by boophilus microplus.to assess the innate resistance of and transmission in naive bos taurus cross bos indicus and purebred bos indicus cattle when placed in a paddock with cattle infected with anaplasma marginale and carrying boophilus microplus ticks.199910685172
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