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identification of ecdysone 22-long-chain fatty acyl esters in newly laid eggs of the cattle tick boophilus microplus.the five major apolar ecdysone esters present in newly laid eggs of the cattle tick boophilus microplus have been purified by h.p.l.c. the quantities of the apolar esters present in the eggs were increased by administration of ecdysone to the mature females. g.c.-m.s. analysis, as their methyl esters, of the fatty acids released from the apolar ecdysone derivatives by alkali, coupled with positive-ion fast-atom-bombardment m.s. of the intact ecdysone esters, showed that the compounds consisted o ...19863030275
the effects of precocene treatment on egg wax production in gené's organ and egg viability in the cattle tick boophilus microplus (acarina ixodidae): an ultrastructural study.wax synthesis by gené's organ, the egg waxing organ of ticks, is by precocene treatment of engorged female boophilus microplus, resulting in desiccated nonviable eggs due to the absence of a waterproofing wax layer. electron microscopy shows that precocene has a destructive effect on the glandular cells of gené's organ. the precocene also inhibited in vitro wax synthesis by the gland cells, indicating a selective cytotoxic effect. oogenesis and oviposition were otherwise unaffected, also suggest ...19863451863
immunization of cattle against boophilus microplus using extracts derived from adult female ticks: effects of induced immunity on tick populations. 19863699973
immunization of cattle against boophilus microplus using extracts derived from adult female ticks: histopathology of ticks feeding on vaccinated cattle. 19863699974
effect of different methods of maintenance on the development and morphology of babesia bigemina in the gut of boophilus microplus.the development and morphology of babesia bigemina in the gut of boophilus microplus ticks were studied during laboratory maintenance of the babesia by four methods: tick transmission in unsplenectomised (intact) calves; tick transmission in splenectomised calves; syringe passage at intervals of five days or less in splenectomised calves; and syringe passage at intervals of six weeks or more in intact calves. the first method had no apparent effect on the development of b bigemina in ticks compa ...19863704330
genetic similarity and variability between natural populations and laboratory colonies of north american boophilus (acari: ixodidae).four natural populations and 4 laboratory colonies of boophilus microplus (canestrini) and a laboratory colony of boophilus annulatus (say) were subjected to electrophoretic analysis to determine levels of genetic similarity and genetic variability. populations of b. microplus exhibited high genetic similarity (i = 0.984 +/- 0.012) indicating that all populations share a relatively undifferentiated gene pool. host vagility is proposed as an important mechanism promoting gene flow in ectoparasite ...19863712179
babesia bovis infection of secretory cells in the gut of the vector tick boophilus microplus. 19863721701
immunization of cattle against boophilus microplus using extracts derived from adult female ticks: feeding and survival of the parasite on vaccinated cattle. 19863721702
bovine babesiosis (babesia bovis infection) in zambia.two cases of babesia bovis, a parasite associated with the tick boophilus microplus, are reported for the first time from the central part of zambia. it is concluded that infected b. microplus ticks are occasionally introduced into central zambia by tick-infested cattle from the north-eastern part of the country where b. bovis is endemic. the spread of b. microplus in southern africa in a westward direction is discussed and related to the epidemiology of bovine babesiosis in zambia.19863727339
a microplate enzyme-linked immunosorbent assay for measuring antibody to anaplasma marginale in cattle serum.an enzyme-linked immunosorbent assay (elisa) method is described for measuring antibody against anaplasma marginale in cattle serum. this method was more sensitive and objective than a previously described elisa method for a. marginale and possible reasons for this are discussed. all 83 cattle experimentally infected with a. marginale (81) or a. centrale (2) developed demonstrable specific antibody but the serums of 98.8% of 839 cattle from cattle tick-free areas did not react by elisa; 378 seru ...19863729834
the inability of a south african babesia bovis vaccine strain to infect boophilus microplus.a strain of babesia bovis that had been attenuated by rapid syringe passage through a series of 23 splenectomized calves was unable to infect its vector boophilus microplus. an attempt to transmit the attenuated australian babesia bigemina g strain with a south african strain of b. microplus was likewise unsuccessful. the epidemiological implication of these observations in terms of babesiosis control is discussed.19863763166
continued functioning of the feeding apparatus during moulting of boophilus microplus as an adaptation of one-host ticks.nymphs of the 1-host cattle tick boophilus microplus remain attached to the host during moulting, but this process is not uniform throughout the tick tissues. the muscles of the pharynx and salivarium remain attached to the cuticle and are functional while the cuticle of the legs has already separated from the underlying epidermis and muscle. the nymphs continue to feed for 2 days after the moulting process in the legs has begun, and they more than double their weight in this time. mouth-part pr ...19863819961
molecular vaccines against parasites.prophylactic vaccines can be expected to be one of the major practical outputs of parasitology research. various groups within australia have pursued the vaccine objective for several years, with particular emphasis on blood-stage falciparum malaria in man, intestinal helminths of sheep and cattle, cutaneous myiasis (blowfly strike) in sheep, cysticercosis in sheep and cattle, bovine babesiosis, and cattle ticks. other vaccine programmes are concerned with giardiasis, filariasis, toxoplasmosis, ...198615462818
effect of age of boophilus microplus larvae (acari: ixodidae) on attachment to cattle. 19873820234
tick transmission of anaplasma centrale.anaplasma centrale was isolated from a field collection of rhipicephalus simus. transstadial transmission of a. centrale with adult ticks was demonstrated, but the infection was not carried transovarially. ticks from this collection were subsequently reared as a non-infected, laboratory strain. it was proved that the onderstepoort live blood vaccine strain of a. centrale, isolated by theiler in 1911, is still tick transmissible after more than 75 years of needle passage through cattle in the lab ...19873587927
ultrastructure of secretory cells in the gut of the cattle-tick boophilus microplus. 19873654050
control of cattle ticks using flumethrin in central zambia. 19873660539
control of cattle ticks. 19873660566
metabolism of ecdysteroids in the female tick amblyomma hebraeum (ixodoidea, ixodidae): accumulation of free ecdysone and 20-hydroxyecdysone in the eggs.[3h]-20-hydroxyecdysone ([3h]-20e) injected into amblyomma hebraeum females 7 days before the beginning of oviposition, viz. at the beginning of vitellogenesis, was converted to 3 polar peaks of unknown nature called 1, 2 and 3, and to apolar conjugates ap1, ap2 and ap3. ap2 have the same retention times as the esters of 20e with long chain fatty acids described in ornithodoros moubata (diehl et al. 1985). however, principally unmetabolized 20e was incorporated into the ovaries, and 16% of the i ...19873693624
[efficacy of chlorfenvinphos in cattle-tick control in the north-western cameroon]. 19873444970
boophilus microplus: passage of bovine immunoglobulins and albumin across the gut of cattle ticks feeding on normal or vaccinated cattle.cattle were vaccinated with antigens from adult female boophilus microplus and haemolymph was collected from female ticks which had engorged on these animals and on matched control cattle. radio-immunoassay for bovine plasma proteins in haemolymph from ticks fed on control cattle showed low concentrations of igg1 and albumin. there was a significant increase in bovine plasma proteins passing across the gut in ticks fed on vaccinated cattle, with an average of 150 times more albumin and four to f ...19873444975
ticks (acari:ixodidae) of the blue and white nile ecosystems in the sudan with particular reference to the rhipicephalus sanguineus group.twenty-four adult ixodid tick species, infesting livestock and some wildlife hosts along the blue and white nile in the sudan, were identified. three species, boophilus geigyi, rhipicephalus camicasi and r. bergeoni, were recorded for the first time from the sudan. tick numbers on indigenous breeds of cattle (bos indicus) were relatively low, ranging between 17.1 and 40.5 per animal. young cattle grazing with the herd carried significantly fewer ticks than older animals. with the exception of b. ...19873331134
boophilus microplus (ixodid tick): fine structure of the gut basophilic cell in relation to water and ion transport.basophilic cells in the guts of female ticks are derived from the basal remnants of type 2 secretory cells. as viewed by electron microscopy, these cells have microvilli uniformly distributed on the luminal surface, but they lack the abundant pinocytotic vesicles and lysosomes characteristic of digest cells. the cytoplasm is filled with well organized rough endoplasmic reticulum, golgi complexes and secretory granules. infoldings of a basal labyrinth extend the contact of the cell with the under ...19873453788
use of taylor's power law in examining the spatial distribution of free-living boophilus microplus (acari: ixodidae) larvae in pastures in puerto rico.taylor's power law (y = amb) was used to analyze the spatial pattern of boophilus microplus (canestrini) larvae in tropical pastures. the index of aggregation b was 2.75 and showed that larvae were highly aggregated. the b-values differed significantly among certain pastures (lsd, p less than 0.05), and pasture type and use could have contributed to differences in b. the use of taylor's power law to adjust for sampling inconsistencies that occur in tropical pastures where regimented sampling can ...19873453787
cholinesterase insensitivity: a mechanism of resistance in mexican strains of boophilus microplus (acari: ixodidae) against coumaphos. 19883404542
metabolism of coumaphos in susceptible and resistant strains of boophilus microplus (acari: ixodidae). 19883351878
vaccines to protect hereford cattle against the cattle tick, boophilus microplus.vaccines made from gut and gut and synganglion tissue dissected from boophilus microplus gave 87% and 80% protection, respectively, compared with adjuvant-injected controls in cattle against three infestations with 20,000 larval ticks administered over 14 days. a vaccine prepared from synganglion alone did not protect cattle. ticks collected from vaccinated cattle produced 95% and 91% fewer eggs, respectively, than ticks from control animals. vaccinated cattle were protected (36%) 7 months after ...19883350577
ticks parasitising the indian buffalo (bubalus bubalis) and their possible role in disease transmission.a total of 13 ixodid tick species, boophilus microplus, haemaphysalis bispinosa, haemaphysalis cornupunctata, haemaphysalis himalaya, heamaphysalis montgomeryi, hyalomma anatolicum anatolicum, hyalomma dromedarii, hyalomma marginatum isaaci, hyalomma (hyalommina) brevipunctata, hyalomma (hyalommina) hussaini, nosomma monstrosum, rhipicephalus haemaphysaloides, and r. turanicus were collected off 424 buffaloes from the northwestern states of india. ten tick species, amblyomma testudinarium, b. mi ...19883369083
isolation from the cattle tick, boophilus microplus, of antigenic material capable of eliciting a protective immunological response in the bovine host. 19883372125
selection for resistance to coumaphos in a strain of southern cattle tick (acari: ixodidae). 19883372854
radioimmunoassay for anaplasma marginale antibodies in cattle.a radioimmunoassay is described for use in the detection of anaplasma marginale antibodies in cattle sera. optimal sensitivity and specificity were obtained by using 2 antigens, an a marginale antigen and a rbc antigen (obtained before infection was established) from the same calf. in addition, sera were preabsorbed with rbc from healthy cattle and with sonicated babesia bovis. of 86 sera obtained from cattle with a marginale infection (as determined by blood smear examination or by results of s ...19883377309
kinetic properties of toxic protease inhibitors isolated from tick eggs.1. egg-toxins from rhipicephalus evertsi evertsi, boophilus microplus, boophilus decoloratus and hyalomma truncatum were found to be inhibitors of trypsin and in two cases also of chymotrypsin. 2. fast tight-binding and slow-binding inhibition were observed. 3. immunological identity of the toxins were assessed with ouchterlony immunodiffusion and elisa. 4. the protease content of b. decoloratus and amblyomma hebraeum tick eggs were determined by a linked enzyme assay. 5. the predictive value of ...19883391338
persistent activity of injectable ivermectin in the control of the cattle tick boophilus microplus. 19883407118
effect of mercury vapour on the non-protein thiol content and respiration rate of eggs of the cattle tick boophilus microplus (acari: ixodidae).with continuous and ultimately lethal exposure of eggs of boophilus microplus to mercury vapour, respiration and non-protein thiol decreased to low levels. with sub-lethal exposure, respiration decreased initially and then increased, whereas non-protein thiol (largely glutathione) increased initially and then decreased. this initial increase in glutathione (gsh) which probably resulted from an attempt by the organism to control or reverse the biochemical lesion, did not arise from the oxidized f ...19883409788
flumethrin applied as a pour-on and whole-body spray for controlling cattle tick (acari: ixodidae) on cattle. 19883417920
epidemiology of bovine babesiosis and anaplasmosis in zambia.the serological prevalence of bovine babesiosis and anaplasmosis in the traditional farming sector of six provinces of zambia was determined using the indirect fluorescent antibody test (ifat) for babesiosis and the card agglutination test (cat) for anaplasmosis. antibodies to babesia bigemina occurred throughout the country whereas the prevalence of b. bovis followed the distribution of its tick vector boophilus microplus which is limited to the north-eastern part of the country. low numbers of ...19883070875
hereford cattle immunized and protected against boophilus microplus with soluble and membrane-associated antigens from the midgut of ticks.hereford cattle were immunized with membranes and soluble components extracted from the midgut of boophilus microplus. membrane vaccines protected cattle (91%) against challenge with 3 x 20,000 larval ticks administered at intervals of 7 days. vaccines made from soluble antigens did not protect cattle. antibody levels measured by enzyme-linked immunosorbent assay (elisa) related to the levels of protection induced by vaccination.19883174172
effect of temperature on the ovipositional biology and egg viability of the cattle tick boophilus annulatus (acari: ixodidae).the effect of temperature on the ovipositional biology of boophilus annulatus (say) was determined under laboratory conditions. engorged females subjected to constant temperatures of 12 and 45 degrees c died without ovipositing, while females held at 15 and 40 degrees c laid eggs which did not hatch. the preoviposition period at 25-40 degrees c was 2-3 days; however, significant increases occurred at 20 degrees c (5.2 days) and at 15 degrees c (16.3 days). the number of eggs laid per female was ...19883197576
efficacy of topically applied ivermectin against boophilus microplus (canestrini, 1887) in cattle.systemic efficacy of ivermectin applied topically was evaluated against the cattle tick, boophilus microplus. twenty cattle with induced infestations were randomly allocated to five groups of equal size based on the numbers of engorged female ticks which fell through the slatted floor of individual pens during the 3 days prior to treatments. control cattle were non-medicated. cattle in three groups were given ivermectin at 200, 500 or 1000 mcg kg-1 in a topical formulation applied along the back ...19883201709
a technique for collecting saliva from the cattle-tick boophilus microplus (canestrini, 1887) using chemical stimulation. environmental and temporal influences on secretion yield.1. injection of a pilocarpine solution into the hemocoele of female b. microplus through the respiratory spiracle induced the flow of limpid saliva, collected from the mouth parts with a capillary tube. 2. the time interval between the detachment of the tick from its host and chemical stimulation influenced the volume of saliva secreted; secretion was greater during the first 2 h after detachment. 3. there is a positive correlation between salivary yield and both environmental temperature and re ...19883228628
characterization of tick antigens inducing host immune resistance. ii. description of rabbit-acquired immunity to amblyomma americanum ticks and identification of potential tick antigens by western blot analysis.feeding by adult amblyomma americanum ticks induced a level of immunity in rabbits to subsequent tick feeding that resulted in a significant decrease in tick feeding success and fecundity. histological analysis of tick feeding sites in hosts expressing resistance revealed a predominant eosinophil response, with weak basophil and neutrophil infiltrates. while the basophil was never the dominant granulocyte at the tick feeding sites in resistant hosts, this cell exhibited the greatest increase in ...19883291384
ecological aspects of cattle tick control in central zambia.in ecological studies in central zambia, both climate and ecotype affected population dynamics of tick species. below average rainfall for several years caused a suppression in numbers of rhipicephalus appendiculatus neumann adults. reduction in rainfall leading to changes in grazing patterns is thought to have been responsible for an increase in numbers of amblyomma variegatum fabricius adults in a grassland habitat. there were reasonable correlations between numbers of each tick species on ind ...19892519677
effects of biogenic amines and adrenergic drugs on oviposition in the cattle tick boophilus: evidence for octopaminergic innervation of the oviduct.oviposition in the cattle tick boophilus microplus was arrested by octopamine and the alpha-adrenergic agonists clonidine, tolazoline, and naphazoline, at doses of 25 micrograms per tick. the same effect was obtained with a sublethal dose of amitraz of 10 micrograms per tick. in contrast, the alpha-adrenergic agonists apomorphine, synephrine, phentolamine, metaclopromide and chlorpromazine were ineffective. no mortality was observed at any of the doses tested. reserpine, which depletes endogenou ...19892572407
novel vaccination for control of the babesia vector, boophilus microplus.an antigen was isolated from the tick gut wall. antibody to this antigen bound to the tick gut cells when the ticks fed on immunized animals. gut function in the ticks and tick development were inhibited.19892623756
body weight, tick burden (boophilus microplus), physiological parameters and reproductive efficiency of crossbred zebu cattle.body weight at calving, degree of tick load (boophilus microplus), rectal temperature, respiratory frequency and heart rate were evaluated and correlated to reproductive efficiency in 63 f1 brown swiss x nellore milked animals reared in the tropical region of peru. cows were bred by free natural service, and first ovulation was estimated by progesterone measurements. the physiological parameters were registered at morning milking (04.00 to 06.00) at an average air temperature of 22.4 +/- 0.9 deg ...19892629511
vaccination against boophilus microplus: localization of antigens on tick gut cells and their interaction with the host immune system.cattle have been vaccinated against boophilus microplus with antigens derived from partially fed female ticks. the immune response of the host lyses the gut cells of adult ticks, causing a reduction in the number, weight and reproductive capacity of engorging ticks. this response is different from the immunity that cattle acquire after repeated tick infestation. evidence is presented that the antigens used in vaccination are located on the plasma membrane of the gut cells and it is unlikely that ...19892667918
genetic resistance of hosts and its influence on epidemiology.evidence for the genetic control of resistance of sheep to gastrointestinal nematode infections was reviewed and compared with that of cattle to infestation with the cattle tick. variation within sheep breeds in resistance to nematode infection is as great as that between breeds, is moderately heritable, and selection of lines of resistant sheep should result in animals carrying worm burdens around 10%-20% of those of unselected animals. the consequences of genetically resistant sheep for the ep ...19892669317
the effect of infection by babesia sp. on some biological parameters of engorged females of boophilus microplus.engorged females (ef) of boophilus microplus tick were collected from hereford, criolla and nelloreheifers of three different herds to study the influence of natural babesial infection on the following biological parameters of the ef: engorgement weight, preoviposition period, minimal egg incubation period, egg hatching and reproductive efficiency index. no detrimental consequences to the reproduction of ef carrying babesial infection were found when compared with those ef in which no kinetes of ...19892670703
cloning and expression of a protective antigen from the cattle tick boophilus microplus.glycoproteins located on the luminal surface of the plasma membrane of tick gut epithelial cells, when used to vaccinate cattle, are capable of stimulating an immune response that protects cattle against subsequent tick infestation. one such tick gut glycoprotein, designated bm86, has been purified to homogeneity and the amino acid sequences of peptide fragments generated by endoproteinase lys-c digestion have been determined. we report here the isolation and characterization of a cdna that enco ...19892690068
effect of different methods of maintenance on the pathogenicity and infectivity of babesia bigemina for the vector boophilus microplus.observations were made on the effects of five different methods of laboratory maintenance on the infectivity and virulence of babesia bigemina for the tick boophilus microplus. the original isolate was highly infective and virulent, causing premature death of engorged female ticks and reduced egg production. maintenance of the strain by syringe passage in unsplenectomised calves at six to 10 week intervals reduced both its infectivity and virulence for ticks. when slow passages were preceded by ...19892704879
toxicology and metabolism of isomers of flumethrin in larvae of pyrethroid-susceptible and resistant strains of the cattle tick boophilus microplus (acari: ixodidae). 19892707107
distribution of some anystid mites (acari: anystidae) in australia and indonesia and their role as possible predators of the cattle tick, boophilus microplus (acari: ixodidae).the geographic and habitat distributions of anystis baccarum, a. jabanica, a. salicinus, and a. sp. b walzia australica womersley and chaussieria warregense in australia and parts of indonesia are presented. laboratory trials showed that a. baccarum will feed upon the larvae of the cattle tick boophilus microplus, whilst a. jabanica also showed some predatory potential. walzia australica and c. warregense had no effect on survival of tick larvae.19892707109
ovicidal activity of topically applied acaricides against eggs of the southern cattle tick (acari: ixodidae).ovicidal activity of coumaphos, diazinon, dioxathion, chlorpyrifos, and crotoxyphos applied topically at 0.125, 0.25, and 0.5% (ai) to 1-d-old, 10-d-old, and 20-d-old eggs of southern cattle tick, boophilus microplus (canestrini), was determined. all acaricides produced some disruption of hatching of eggs in all age classes. coumaphos, diazinon, dioxathion, and chlorpyrifos were most effective in reducing egg hatch of 1-d-old eggs but had little effect against 10- or 20-d-old eggs. although crot ...19892708632
populations of the cattle tick (boophilus microplus) on purebred nellore, ibage and nellore x european crossbreds in the brazilian savanna.studies on purebred nellore cattle and their crosses with fleckvieh, chianina, charolais and the ibagé breed (5/8 aberdeen angus, 3/8 nellore) during 39 months in the field gave mean daily counts for engorging female ticks of 3.3, 25.2, 22.2, 21.0 and 59.7 per animal respectively. annual fluctuations were similar in all groups; with the exception of the purebred nellore mean counts are at levels considered dangerous for the stability of enzootic tick fever.19892711457
immunologic control of a parasitic arthropod. identification of a protective antigen from boophilus microplus.cattle can be vaccinated against the tick boophilus microplus by inducing an immunologic reaction against ag in the tick gut. the uptake of antibody during feeding leads to severe damage to the parasite. one of the responsible tick gut ag has now been purified and characterized: the bm86 ag. it is a membrane-bound glycoprotein present in very low abundance in extracts of partially engorged adult female ticks. it has an apparent m.w. of 89,000, an isoelectric point of 5.1 to 5.6 and an affinity f ...19892745982
hereford cattle protected against boophilus microplus with antigens purified by immunoaffinity chromatography from larval and adult ticks.tick larvae (boophilus microplus) were extracted, fractionated by gel filtration and ion-exchange chromatography, and the fractions assayed by enzyme-linked immunosorbent assay (elisa) against sera from cattle immunized and protected by antigens from the mid-gut of adult ticks. unfractionated, whole larval extracts and selected reactive components were used to vaccinate cattle; they decreased the number of ticks dropped after challenge, but the effect of treatment was not significant. antigens p ...19892759660
detection of babesia bigemina in cattle by a radioimmunoassay incorporating specifically depleted antigen.it was observed that mild acidification (ph less than 4.0) together with solvent extraction of the soluble sonicate of a crude preparation of babesia bigemina infected cattle erythrocytes caused a quantitative loss of b. bigemina-specific antigen. cross-reacting antigen activities with babesia bovis remained intact. these properties were utilized in an assay system wherein antibody response to the specifically depleted antigen preparation was subtracted from the response to the initial crude pre ...19892763443
relationship between the resistance of crossbred cattle to ticks, boophilus microplus (canestrini, 1887) and hyalomma anatolicum anatolicum (koch, 1844).studies were undertaken to determine the effect of repeated pure infestations with boophilus microplus on susceptibility to subsequent pure infestations with hyalomma anatolicum anatolicum, and the effects of pure infestations with both species of tick on susceptibility to a series of mixed infestations. crossbred (bos indicus x bos taurus) calves were infested with boophilus microplus (17 times), h. a. anatolicum (four times), followed by five mixed infestations of b. microplus and h. a. anatol ...19892763448
class i antigens of the bovine major histocompatibility system and resistance to the cattle tick (boophilus microplus) assessed in three different seasons.two consecutive calf crops consisting of 141 three-quarters brahman/one-quarter shorthorn cattle were assessed for resistance to the australian cattle tick boophilus microplus in may, july and october 1983. although the level of expressed resistance to artificial infestation varied considerably between seasons, the animals maintained very similar rankings for resistance in all three seasons, and the repeatability of tick resistance ranged from 0.59 to 0.82. the cattle were typed for 30 bovine cl ...19892763449
formulation of medium for tick cell culture.we examined the effectiveness of bovine cholesterol concentrate in reducing the high level (10-20%) of fetal bovine serum (fbs) necessary to promote tick cell growth in vitro. tick cell lines isolated from embryos of anocentor nitens (ane 58), boophilus microplus (bme 26), and rhipicephalus appendiculatus (rae 25) were used. they were incubated in l-15 (bme 26) or l-15b (ane 58 and rae 25) supplemented with 10% tryptose phosphate broth (tpb), 5% (ane 58 and bme 26) or 3% fbs, 10-90 microns/ml ch ...19892766897
synthetic pyrethroid resistance in field samples in the cattle tick (boophilus microplus).first evidence of resistance to synthetic pyrethroids in the cattle tick in australia, other than the pre-existing cross-resistance in ddt-resistant ticks, has emerged. three new strains have been investigated and characterised. the first, detected in central queensland, showed increased ability to detoxify pyrethroids resulting in a marginal loss of efficacy of all pyrethroid tickicides tested, except flumethrin. subsequently two more strains have been detected, with serious implications for ch ...19892775054
the effect of antigen concentration and vaccine regimen on the immunity induced by membrane antigens from the midgut of boophilus microplus.sheep and cattle were immunized with membrane antigens extracted from the midgut (gm) of the cattle tick boophilus microplus, and antibody levels were measured by enzyme-linked immunosorbent assay (elisa). one microgram of gm induced an antibody response in sheep comparable to that induced by 500 micrograms gm. single or divided doses of 500 micrograms gm induced the same antibody levels in sheep over 12 weeks. cattle vaccinated with either 500 micrograms gm in two doses or with 50 or 500 microg ...19892807382
effect of age on cholinesterase activity and protein of unfed larval ticks.the cholinesterase (ache) activity and total protein in homogenates of unfed larvae of amblyomma americanum (l.), a. cajennense (fabricius), a. maculatum koch, anocentor nitens neumann, and boophilus microplus (canestrini) were determined weekly in ticks 1-6 wk of age. there was a considerable variation in total protein, ache, and the ratio of ache to protein as the ticks aged. however, ache activities were constant or increased with age and total protein levels were constant or decreased. no di ...19892918444
protective efficacy of antigens solubilized from gut membranes of the cattle tick, boophilus microplus.triton x-100, sds, n-octyl glucoside, and conditions of alkaline ph and high and low ionic strength, were used to solubilize membranes prepared from the mid-gut of the cattle tick boophilus microplus. hereford cattle (bos taurus) were immunized with soluble membrane antigens in saponin, and then challenged twice with 20,000 tick larvae, 7 days apart. all soluble extracts, except that extracted with high ionic strength buffer, provided significant protection (56-78%) (p < 0.05) to immunized cattl ...198915493278
the expression of bovine lymphocyte antigen and response of hereford cattle to vaccination against boophilus microplus.the influence of the bovine lymphocyte antigen mb5 on the immune response of hereford cattle to antigens of the tick (boophilus microplus) was examined. groups of cattle having or lacking the antigen mb5 (mb5+ and mb5-, respectively) were vaccinated with either soluble extracts of the gut membrane of adult ticks and adjuvant or injected with adjuvant alone. cattle vaccinated with soluble gut membrane were significantly protected from two challenges with ticks. protection against ticks was not si ...19902121658
[natural anaplasma marginale infection in 2 cattle herds with different levels of boophilus microplus tick infestation].the dynamics of natural infections by anaplasma marginale was studied in two adjacent dairy farms with different levels of boophilus microplus infestation. the farms were located in the enzootic area of bovine anaplasmosis of the northwest of argentina. the study was carried out in 35 calves from birth in march-august 1985 to march 1986. the infection rate by a. marginale was evaluated by the observation of blood films and by determination of specific antibodies. the degree of infestation by b. ...19902132783
chromatography and generation of specific antisera to synthetic peptides from a protective boophilus microplus antigen.four oligopeptides corresponding to predicted antigenic regions of the protective bm86 glycoprotein of the cattle tick boophilus microplus were synthesized and purified. three were conjugated to carrier proteins and antisera raised in rabbits and cows. all elicited antipeptide antibodies that recognized bm86 and recombinant derived products in western blots; however, only one produced antiserum capable of recognizing native bm86 in an indirect immunofluorescence assay. ticks fed in vitro on this ...19902229227
expression and secretion in aspergillus nidulans and aspergillus niger of a cell surface glycoprotein from the cattle tick, boophilus microplus, by using the fungal amds promoter system.a cell surface glycoprotein (bm86) from cells of the digestive tract of the cattle tick boophilus microplus, which has been shown to elicit a protective immunological response in vaccinated cattle, was expressed and secreted in the filamentous fungi aspergillus nidulans and aspergillus niger by using the fungal amds promoter system. the cloned gene coded for the bm86 secretory signal and all of the bm86 mature polypeptide except for the hydrophobic carboxy-terminal segment. high levels of bm86 m ...19902275533
perspectives for subunit vaccines for the control of ticks.for the first time, successful vaccination against a tick has been carried out using a single defined antigen. further, it has been shown that it is feasible to produce active antigenic material by recombinant dna technology. this represents a significant advance towards the development of an alternative means of tick control. nevertheless, as with any new product and new technology, much developmental work still has to be done before one can be confident that a practical means of tick control w ...19902284131
the isolation and transmission of an unidentified babesia sp. to cattle by hyalomma truncatum koch 1844.an unidentified babesia sp. which causes a mild disease in cattle was isolated in a splenectomized ox that received pooled blood from field cattle. that this organism is pleomorphic and resembles babesia occultans makes it difficult to differentiate between these organisms microscopically. initially, it was suspected that this babesia could be b. occultans. several attempts to transmit this parasite transovarially with hyalomma marginatum rufipes, the vector of b. occultans, failed. continued ef ...19902293131
larval membrane antigens protect hereford cattle against infestation with boophilus microplus.hereford cattle (bos taurus) were immunized with antigens solubilized with triton x-100 from larval membranes of the cattle tick (boophilus microplus). based on tick egg production compared to control cattle, vaccinated cattle were protected (78%) against challenge with 2 x 20,000 tick larvae. the soluble triton x-100 extract of tick larval membranes was further purified by immunoaffinity chromatography, using immunoglobulin ligands (igg1 and igg2) from three immune steers, previously vaccinated ...19902314923
the relationships among ecto- and endoparasite levels, class i antigens of the bovine major histocompatibility system, immunoglobulin e levels and weight gain.natural infestations of the cattle tick boophilus microplus, levels of the buffalo fly haematobia irritants exigua and faecal nematode egg concentrations (bunostomum phlebotomum, cooperia spp., haemonchus placei, oesophagostomum radiatum and trichostrongylus axei) were assessed in 221 belmont red calves during the post-weaning period, when the animals were between 9 and 18 months of age. in addition, the 98 males of this group were challenged with b. microplus larvae on two separate occasions. t ...19902316176
humoral immune responses of hereford cattle vaccinated with midgut antigens of the cattle tick, boophilus microplus.vaccination of cattle with midgut membrane (gm) antigen derived from the cattle tick, boophilus microplus, infected with the adjuvant quil a, resulted in significant increases in total immunoglobulins, mainly in the igg1 and igg2 fractions of the serum. analysis of the anti-gm antibody levels of vaccinated cattle showed that the levels of igg, igg1 and complement-fixing antibodies were significantly correlated to protection against infestation with cattle ticks. anti-gm antibodies of the igg2 an ...19902320378
ecological aspects of four species of ticks found on cattle in salta, northwest argentina.the seasonal activity of amblyomma cajennense, amblyomma neumanni, amblyomma parvum and boophilus microplus on cattle was studied in a ranch located in the northern part of the phytogeographical district of the chaco serrano where the habitat had suffered minimal human disturbance. the female ticks on one side of 10-25 cows were counted at intervals of 20-50 days from 29 october 1985 to 5 november 1986. the percentage of cattle parasitized with larvae and nymphs of amblyomma was recorded, along ...19902343535
immune responses of infected and vaccinated hereford cattle to antigens of the cattle tick, boophilus microplus.responses of infested and vaccinated hereford cattle to boophilus microplus antigens were measured by enzyme-linked immunosorbent assay (elisa), lymphocyte blastogenesis assay (lba) and intradermal skin tests. responses against soluble salivary gland extracts (sgs), salivary gland membrane (sgm), soluble gut extracts (gs), gut membrane (gm), soluble larval extracts (ls) and larval membrane (lm) antigens were tested. in one experiment, cattle infested with up to 160,000 ticks had positive cellula ...19902349785
ecology and phenology of cattle ticks in zambia: development and survival of free-living stages.a study on development and survival of free-living stages of three important cattle ticks in zambia, amblyomma variegatum fabricus, boophilus decoloratus koch, and rhipicephalus appendiculatus neumann, was carried out to complement studies on seasonal dynamics of parasitic stages. different instars of engorged ticks were exposed under quasi-natural conditions according to the season in which they occur naturally. generally, development rates of all stages of the three species were related to tem ...19902350995
failure of white-tailed deer, odocoileus virginianus l., to sustain a population of cattle ticks, boophilus annulatus (say), through successive generations.cattle ticks, boophilus annulatus (say), previously reared only on cattle, were placed on 3 white-tailed deer, odocoileus virginianus l. ticks were maintained through successive generations solely on the same deer as they aged (3, 6, and 9 mo of age) and received repeated challenges (0, 1, and 2 previous challenges). cattle were infested simultaneously to assess tick viability and provide a comparison of tick numbers, female weight, egg mass weight, and egg hatch. the initial infestation (3,000 ...19902352065
clinico-biochemical use of serum acetylcholine esterase following treatment with synthetic pyrethroids, cypermethrin and fenvalerate, in cattle and buffalo experimentally infested with boophilus microplus.following treatment, cypermethrin and fenvalerate, were found to have inhibitory effect on serum acetylcholine esterase (ache) activity of cattle and buffalo experimentally infested with b. microplus. the pattern of ache activity in infested-pyrethroid-treated group was found to be significantly different from either healthy or tick-infested control. there was transient increase in the enzyme activity initially, followed by gradual decline and subsequent increase leading to normal level within 7 ...19902365420
estimation of the potential demand for a bovine babesiosis and anaplasmosis vaccine in argentina.a survey to estimate the potential demand for a bovine babesiosis and anaplasmosis vaccine was carried out by a postal questionnaire sent to 4407 veterinarians in the north and centre of argentina. twenty-three percent of the questionnaires (1047) were answered; 317 (7.2% of the total, 30% of those answered) pointed out the occurrence of the diseases and/or probable demand for the vaccine. the minimum and maximum demands were 407,892 and 982,300 doses for anaplasmosis, and 272,496 and 631,400 do ...19902382381
distribution of boophilus species ticks in swaziland.recent outbreaks of bovine babesiosis caused by babesia bovis in swaziland had indicated the presence of the vector tick boophilus microplus in the country although it had never before been directly identified. engorged female boophilus ticks were collected from cattle at diptanks in the course of a tick resistance survey and used to map the distribution of the two different species of boophilus. b. decoloratus was found to be widespread throughout the country. b. microplus was identified for th ...19911763439
new records for rhipicephalus bursa, boophilus microplus, b.decoloratus and hypoderma lineatum from libya. 19911768917
re-assessment of tick control after immunization against east coast fever in the eastern province of zambia.east coast fever, caused by the protozoon theileria parva and transmitted by the ixodid tick rhipicephalus appendiculatus is one of the most important cattle diseases in east and central africa, responsible for considerable direct losses and necessitating expensive control measures. traditionally, the disease was controlled by means of intensive tick control. the belgian animal disease control project was requested to study the disease epizootiology and vector ecology in order to formulate and i ...19911793284
ticks (ixodidae) parasitizing humans in four provinces of north-western argentina.in four provinces of north-western argentina (catamarca, jujuy, salta and tucumán), between march 1976 and march 1990, 514 ticks were found on humans. they were identified as rhipicephalus sanguineus group (1 male), boophilus microplus (6 male, 1 female), amblyomma parvum (9 male, 13 female), a. cajannense (35 male, 30 female, 81 nymphs), a. neumanni (33 male, 41 female, 144 nymphs) and amblyomma spp. (10 nymphs, 110 larvae). most of the ticks were from the phytogeographical region of chaco, one ...19911809248
immune responses of cattle to biochemically modified antigens from the midgut of the cattle tick, boophilus microplus.treatment of membrane antigens of the midgut (gm) of the cattle tick, boophilus microplus with sodium metaperiodate (periodate), pronase and lipase significantly inhibited the reactivity of the gm with antibodies in the sera of 57 cattle vaccinated with gm. treatment of gm with periodate only removed the correlation between antibody reactivity of sera and protection against infestation with ticks. a monoclonal antibody (moab qu13), which recognises protective antigens solubilized from gm (lee + ...19911811216
non-random mating between boophilus microplus and hybrids of b. microplus females and b. annulatus males, and its possible effect on sterile male hybrid control releases.when boophilus microplus and type-ii hybrids (b. microplus females x b. annulatus males) were released simultaneously onto bovine hosts, mating between the two forms appeared not to be at random. there were more contypic and fewer intertypic matings than predicted under an assumption of panmixia. an examination of the patterns of matings revealed that more of the matings on the first two days of detachment were between the two sexes of b. microplus. engorged females dropping on the last four day ...19911860415
antigens of amblyomma americanum ticks recognized by repeatedly infested sheep.sera were taken from 3 sheep that had been infested 5 times with amblyomma americanum and that exhibited manifestations of humoral depression to homologous antigens and anti-tick resistance. proteins extracted from the intestine or salivary glands of unfed ticks or salivary glands from partially (3-day) fed ticks were analyzed by polyacrylamide gel electrophoresis (page) and sodium dodecyl sulfate-page. antigens recognized by the sheep in the same materials before and after each infestation were ...19911919918
predation of ticks of the rhipicephalus sanguineus (latreille, 1806) group and boophilus microplus (canestrini, 1888) (acari: ixodidae) by nothura temminck, 1815 (aves: tinamidae) in salta, argentina. 19911937269
transmission of a spotted fever group rickettsia by amblyomma hebraeum (acari: ixodidae).amblyomma hebraeum, a cattle tick common in southern africa, was demonstrated to be capable of maintaining an infection with an unclassified spotted fever group rickettsia both transtadially and transovarially. all feeding stages of the tick transmitted the infection to rabbits. the rickettsia was isolated and found to be serotypically distinct from three strains of rickettsia conorii by microimmunofluorescence. rabbit serum titers were found to be higher with indirect fluorescent antibody (ifa) ...19911941925
isolation of protective antigens from the gut of boophilus microplus using monoclonal antibodies.monoclonal antibodies (mab) were produced against midgut membrane (gm) antigens of boophilus microplus. the isotypes of these mab were established and their specificity characterized using double diffusion and western blotting. gm antigens solubilized by triton x-100 were precipitated by mab qu13, and the precipitate was then injected into cattle to test for the presence of protective antigens. vaccinated cattle challenged with 10-day-old larval ticks showed evidence of protection with a 62% red ...19911997395
computer simulation of boophilus cattle tick (acari: ixodidae) population dynamics.a comprehensive computer model was developed for simulation of the population dynamics of the cattle ticks, boophilus microplus (canestrini) and b. annulatus (say). the model is deterministic and based on a dynamic life table with weekly time steps. the model simulates the effects of major environmental variables, such as ambient temperature, saturation deficit, precipitation, type of pasture, type of cattle, and cattle density on boophilus cattle tick population dynamics. general validity of th ...19912056504
histochemical localisation of acid phosphatase and non-specific esterase in the midguts of two species of tick, boophilus microplus and rhipicephalus appendiculatus, as determined by light microscopy.serial sections of glycol methacrylate-embedded and frozen midguts of boophilus microplus and rhipicephalus appendiculatus were studied histochemically by light microscopy. the use of the naphthol as-tr phosphate technique combined with glycol methacrylate embedding enabled the precise localisation of lysosomal enzyme activity, despite the ubiquity of haematin granules in tick midgut epithelia. the presence of acid phosphatase and non-specific esterase activity in the same cells was observed in ...19911724321
vaccination with 'concealed' antigens: myth or reality?cattle infested with the tick boophilus microplus produce antibodies to intrinsic membrane glycoproteins of the tick, as well as to bm86, a well characterized antigen from the tick gut. several factors explain how cattle could produce antibody to such antigens, which one would expect to be 'concealed' from the host's immune system, during natural infestation. it has been shown that the carbohydrate determinants on many tick glycoproteins are cross-reactive immunologically and that the reaction o ...19911725819
vaccine r & d at csiro's division of tropical animal production.the extensive research on animal vaccines being undertaken by the csiro division of tropical animal production in brisbane is summarised in this paper. much of the research is being developed in conjunction with commercial partners. vaccines are being developed for the cattle tick, babesia, anaplasma, sheep blowfly, buffalo fly and bovine ephemeral fever.19911367735
survival of larvae of boophilus annulatus, boophilus microplus, and boophilus hybrids (acari: ixodidae) in different temperature and humidity regimes in the laboratory.the survival period for larvae of boophilus annulatus (say), boophilus microplus (canestrini) and hybridized boophilus ticks was determined by exposure to various combinations of temperature (20, 25, 30 and 35 degrees c) and relative humidity (32, 63, 75, 84 and 97% rh) in the laboratory. results indicated that within a given temperature and rh regime, there was no difference (p greater than 0.05) in larval survival among the three species tested, indicating that these ticks respond similarly ov ...19911788937
studies on the development and survival periods of the non-parasitic stages of boophilus microplus (canestrini), in the climatic conditions of ranchi (india).engorged female ticks of boophilus microplus were exposed in wire-gauze cylinders and glass tubes in an experimental grass plot at monthly intervals during 1989, and egg laying, egg development and larval survival periods observed and recorded. rainfall and atmospheric relative humidity had an important influence on tick activity. egg production was maximum, hatching percentage was high, incubation and prehatch periods were short, and larval survival and total longevity periods were long for tic ...19921466134
histochemical changes in the midgut of two ixodid tick species boophilus microplus and rhipicephalus appendiculatus during digestion of the blood meal.the changes in the midgut epithelia of two ixodid tick species, boophilus microplus and rhipicephalus appendiculatus, have been studied using several histochemical techniques. it was revealed that there is an accumulation of rna at the time of tick attachment to the host and prior to the arrival of the blood meal, indicating that the midgut digest cell is furnished with the machinery characteristic of a synthetic cell. there appears to be a synchrony in the appearance of granules with peroxidase ...19921373357
a survey of cattle tick control practices in the eastern cape province of south africa.current cattle tick control practices and producer attitudes towards tick control in the eastern cape province of south africa are discussed. these were ascertained from answers to a questionnaire survey to which 31.2% of farmers responded. in general, producers favoured intensive tick control. beef and dairy farmers had a definite preference for synthetic pyrethroid acaricides, the majority followed a 25 times p.a. treatment frequency and most changed acaricides because of price. beef producers ...19921437023
efficacy of cyhalothrin and lambdacyhalothrin against boophilus microplus (acari: ixodidae).a study was conducted to determine the efficacy of cyhalothrin and lambdacyhalothrin as a whole-body spray and lambdacyhalothrin as a pour-on application on cattle infested with boophilus microplus (canestrini). a laboratory bioassay was also done with both spray formulations. cattle were infested with all parasitic life stages of b. microplus, then treated with 0.007 or 0.01% (ai) concentrations of cyhalothrin as a spray; 0.005, 0.007, or 0.01% (ai) concentrations of lambdacyhalothrin as a spra ...19921464689
computer simulation of babesia bovis (babes) and b. bigemina (smith & kilborne) transmission by boophilus cattle ticks (acari: ixodidae).a computer model was developed to simulate the processes involved in transmission of the cattle fever parasites babesia bovis (babes) and babesia bigemina (smith & kilborne) between cattle and boophilus ticks. the model of babesia transmission was combined with a dynamic life history model for population dynamics of the tick vectors, boophilus microplus (canestrini) and b. annulatus (say). epidemiological parameters and relationships in the model include the reduction in fecundity of infected ti ...19921495038
test for assortative mating between boophilus microplus and boophilus annulatus (acari: ixodidae).the closely related cattle ticks, boophilus microplus (canestrini) and b. annulatus (say), were tested for possible assortative mating under conditions designed to mimic those in the field. patterns in the numbers of the four possible types of matings were generally indicative of a preference for conspecific mates in both species. there were significantly more conspecific and fewer interspecific matings than would be predicted from the observed frequencies of males and females among the two spec ...19921495080
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