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relative susceptibility of jamaican strains of boophilus microplus, amblyomma cajennense, and anocentor nitens to various acaricides. 1977604370
mortality, weight loss and anaemia in bos taurus calves exposed to boophilus microplus ticks in the tropics of colombia.one hundred and sixteen pure-bred normandy calves previously immunised against babesiosis and anaplasmosis were transported to the caribbean coast of colombia where they divided into 2 equal groups and placed in separate pastures. one group sustained heavy infestation with boophilus microplus ticks. the second group became lightly infested. the heavily infested calves suffered average losses in body weight of 38 kg and a 48% decrease in mean packed cell volume. twenty-three (40%) died 16 to 39 d ...1979552671
a note on the transmission of babesia bovis (syn b argentina) by the one-host tick, boophilus microplus.boophilus microplus infected with babesia bovis were transferred artificially from one splenectomised calf to another during each moult in the parasitic life cycle of the tick. eggs from the engorged female ticks recovered at the end of the cycle were incubated and the resulting larvae used to infest more splenectomised calves. babesia bovis was transmitted only by the original larvae used at the commencement of the experiment and it was concluded that the protozoan parasite did not persist in a ...1979262611
norepinephrine as principal catecholamine in a specific neurone of an invertebrate (boophilus microplus: acarina).norepinephrine has been identified as the principal catecholamine in individual neurons of the synganglion of an arthropod, the cattle tick boophilus microplus. this suggests that norepinephrine may have a hitherto unsuspected major physiological role in at least one group of invertebrates.1978720511
distribution of catecholamines in the cattle tick boophilus microplus. 197723237
boophilus microplus: rejection of larvae from british breed cattle.larvae of boophilus microplus were labelled with [32p] and used to study the rejection of larvae from british breed cattle with different levels of resistance. on animals of high resistance the loss of larvae due to grooming ranged from 9-54% during the first 24 h of infestation, and more time was spent grooming by these animals. most of the grooming activity could be attributed to the presence of tick larvae and the presence of older tick stages did not increase the percentage of larvae lost. g ...1978662415
rusa deer (cervus timorensis) as a host for the cattle tick (boophilus microplus) in papua new guinea.the rusa deer (cervus timorensis) is more resistant to the cattle tick (boophlilus microplus) than are britsh breed cattle in papua new guinea. the average yield of replete female ticks from deer was 1.6% (0.3-3.2%) as compared to 11.2% (3.4-23.1%) from calves. ticks from deer were more slender, lighter in weight and produced fewer eggs (mean 1,800) than did ticks from calves (mean 2,200) but the deer was shown to be an effective host. a cervid population can maintain a tick population in the ab ...1977864854
transmission of babesia bigemina by transfer of adult male boophilus microplus. 1978687283
sequential changes in salivary gland structure during attachment and feeding of the cattle tick, boophilus microplus. 1978681074
boophilus microplus: passive transfer of resistance in cattle.plasma from cattle highly resistant to the tick boophilus microplus conferred some resistance to unexposed calves. in contrast plasma from hosts of low resistance had no significant effect compared with plasma from unexposed donors.1976932924
the fine structure of merozoites of babesia bovis in the gut epithelium of boophilus microplus.electron microscopic studies on merozoites of babesia bovis in epithelial cells of the gut of boophilus microplus revealed that the pellicle apparently consists of 3 membranes, and an osmiophilic layer intimately associated with microtubules. micropores in the pellicle were often associated with micronemes. an unidentified tubular structure extended from the anterior polar ring to the nuclear region where it appeared to be associated with the nuclear envelope. a golgi complex, typical protozoan ...1976940662
responses of cattle to allergens from boophilus microplus. 1978681073
methods to improve the health of cattle in the tropics: conclusions and economic appraisal.the results of the immune responses of immunised and chemoprophylactically treated calves to tick-borne (boophilus microplus) challenge indicate that the system of immunisation was effective in protecting cattle against anaplasma marginale, babesia argentina (bovis), and b. bigemina. however, chemoprophylaxis was effective only against babesia spp. but not against a. marginale. both methods showed a substantial advantage over no control system when using native cattle breeds in a zone endemic fo ...1978705891
the duration of latent infection and functional immunity in droughtmaster and hereford cattle following natural infection with babesia argentina and babesia bigemina.tne droughtmaster and 9 hereford cattle were born in an enzootic babesiasis area and became naturally infected with babesia argentina and b.bigemina during a 3 year period. they were then kept free of cattle ticks (boophilus microplus) for the remainder of the experiment. annually for the next 3 years their individual infection status with babesia was determined by sub-inoculation of blood into splenectomised calves. at the end of this period the functional immunity of all cattle was challenged ...1978655965
differences in the life cycles between a vaccine strain and an unmodified strain of babesia bovis (babes, 1889) in the tick boophilus microplus (canestrini).developmental forms of 2 strains of babesia bovis (babes) were studied in the tick vector boophilus microplus (canestrini). one strain (designated t) was shown to be infective for the tick, and the other (nt) to have lost infectivity for the tick, because of repeated blood passaging in cattle. parasites of the 2 strains in gut contents of adult female ticks were similar during the first 16 h post-repletion (pr), but thereafter their structure differed. from 16-64 h pr, the majority of t strain p ...1978739414
acaricidal susceptibility of five strains of boophilus microplus from four caribbean countries. 1978627670
chemistry, biological activity, and uses of formamidine pesticides.the formamidines, a relatively new group of acaricide-insecticides, are novel both in their range of biological activities and in their mode of action, which is presently unknown. this paper is a review of the historical development, properties, structures, uses, and chemistry of this group of pesticides, with particular emphasis on chlordimeform (galecron or fundal), n'-4-chloro-o-tolyl-n,n-dimethylformamidine, and amitraz, 1,3=di-(2,4-dimethylphenylimino)-2-methyl-2-azapropane. their biologica ...1976789070
bovine babesiosis: severity and reproducibility of babesia bovis infections induced by boophilus microplus under laboratory conditions.a total of 61 intact holstein-friesian calves were exposed to babesia bovis (= b argentina) by the injection of infected blood or the application of infected boophilus microplus larvae. tick-induced infections were uniformly severe, even when induced by relatively small numbers of infected ticks. in contrast, calves infected with carrier blood experienced mild, subclinical reactions despite detectable parasitaemia. the greater severity of tick-induced reactions appeared to be due to the large nu ...1978674841
epidemiology and control of anaplasmosis in australia.anaplasmosis occurs in those areas of northern and eastern australia infested by the cattle tick boophilus microplus but it has been studied intensively only in queensland. anaplasmosis is predominantly a disease of autumn and winter and of cattle greater than 1 year of age. the complement fixation test has been used in serological surveys of the tick-infested areas of the state. both clinical and subclinical infections occur only in tick-infested areas and they are both more frequent in bos tau ...1979553977
ixodicidal resistance in boophilus microplus (canestrini) in the republic of south africa and transkei.a series of in vitro trials using unfed larvae and fully fed adult ticks confirmed ixodicidal resistance in the one-host pantropical blue tick, boophilus microplus (canestrini). fifty-seven of 64 field isolates were resistant to arsenic; 10 of 56 were resistant to toxaphene; 1 of 5 were resistant to lindane; 3 of 5 were resistant to dieldrin; 3 of 19 were resistant to ddt and 8 of 55 were resistant to the organophosphorus ixodicide, dioxathion. one of the field isolates resistant to dioxathion w ...1979553968
the potential of some synthetic pyrethroids for control of the cattle tick (boophilus microplus).as part of a continuing programme to aid in the development of new acaricides, the potentials of three synthetic pyrethroids, permethrin, cypermethrin and decamethrin, were assessed against a range of resistant strains of the cattle tick (boophilus microplus). the compounds were shown to be acaricidal, with decamethrin the most effective, giving efficient control of susceptible and organo-phosphorus resistant strains of the cattle tick at concentrations as low as one fifth of those previously us ...1979539930
the influence of temperature, relative humidity and host factors on the attachment and survival of boophilus microplus (canestrini) larvae to skin slices. 1979528141
immunosuppression by babesia bovis against its tick vector, boophilus microplus. 1978643072
[ultrastructural characteristics of the salivary glands of the taiga tick, ixodes persulcatus (ixodidae). i. the granulosecreting alveoles of the fasting female].two types of granulosecreting alveoles were found in salivary glands of hungry females by means of electron microscopy of ultrafine sections. alveoles of the iind type occur in the anterior helf of the gland. they are not numerous and consist of three types of secretory cells (a, b, c) surrounding the inneralveolar cavity. the secretory cells are separated from each other and from the basal membrane by the strands of the epithelial cells p. three types of spherical inclusions were found in the s ...1979514626
failure of vaccine strains of babesia bovis to regain infectivity for ticks during long-standing infections in cattle.two strains of babesia bovis that were known to have lost infectivity for the normal tick vector, boophilus microplus, due to repeated blood passaging in cattle, were studied to determine whether the strains would regain infectivity for ticks during longstanding infections. parasitaemias were monitored in 4 chronically infected calves that were regularly infested with ticks. two strains of ticks known to be susceptible to infection with unmodified strains of b. bovis were used. adult female tick ...1977588177
the relation between skin histamine concentration, histamine sensitivity, and the resistance of cattle to the tick, boophilus microplus.cattle with different degrees of resistance to boophilus microplus have responses to tick allergen which correlate with their resistance level. the total amount of histamine in the skin also correlates with both resistance and the immediate hypersensitivity reactions, but the sensitivity to injected histamine does not. treatment with the antihistamine drug mepyramine maleate suppresses the cutaneous hypersensitivity reactions. the results suggest that the main pharmacologically active agent in t ...1979483974
the nonpolar egg wax lipids of the cattle tick, boophilus microplus (canestrini).about 40% of the lipids of the egg wax of boophilus microplus are nonpolar and comprise hydrocarbons (10%) and wax esters (90%). the hydrocarbon fraction is 87% unbranched alkanes, the major components being n-nonadecane (10.8%), n-eicosane (12.1%), and n-heneicosane (9.8%). this fraction also contains 2,4,6-cholestatriene (4.6%). the majority of the acids are branched (77%) the major components being 12-methyl-tetradecanoic (16.3%) and branched hexadecanoic acids (28%). the major alcohols are n ...1977557717
prostaglandin in the saliva of the cattle tick boophilus microplus.previous studies of saliva from engorged female cattle ticks revealed a component which induced contration of some isolated smooth muscles. fractionation and further characterisation have shown that this substance is of the "slow-reacting" type, but that it is neither a bradykinin nor slow-reacting substance of anaphylaxis. the substance is deactivated by incubation with 15-hydroxprostaglandin dehydrogenase and its pharmacological properties also support its classification as a prostaglandin. a ...19761021092
some aspects of the epidemiology and control of bovine babesiosis in australia.a short account of the epidemiology and control of babesiosis in australia is presented. epidemiological topics discussed include differences in the transmission of babesia bovis and b. bigemina by the cattle tick, boophilus microplus and the relative prevalence, disease incidence and pathogenicity of b. bovis and b. bigemina. circumstances under which babesiosis occurs in australia are described. in the section on control, only vaccination is discussed. changes in the preparation of babesial va ...1979399977
intercellular junctions in the hypodermis, salivary gland and gené's organ of the cattle tick, boophilus microplus.the intercellular junctions that occur in the hypodermis, gené's organ, and the salivary glands of the tick, b. microplus, are described. the epithelial cells of the hypodermis are connected by spot desmosomes and septate junctions and the secretory cells of gené's organ by septate and gap junctions. the cap cells in the alveoli of the salivary gland connect to adjacent cells by gap junctions, hemidesmosomes and septate junctions into which microtubules are inserted.1979509494
the invasion and growth of babesia bovis in tick tissue culture.erythrocytic forms of babesia bovis inoculated into cell cultures of the tick boophilus microplus invaded the tick cells and showed multiplication for up to 48 h after inoculation.1979467577
characterization of a proteolytic-enzyme inhibitor with allergenic activity. multiple functions of a parasite-derived protein.1. a trypsin inhibitor from the tick boophilus microplus was purified by ion-exchange chromatography and gel filtration. 2. it is pure by the criteria of constant specific activity on gel filtration and by electrophoresis on polyacrylamide gels containing sodium dodecyl sulphate. 3. the protein undergoes reversible polymerization, dissociating at low ph. 4. the apparent molecular weight measured by electrophoresis on polyacrylamide gels containing sodium dodecyl sulphate is 18,500. 5. inhibition ...1979426780
immunologic relations between cattle and ticks, specifically between cattle and boophilus microplus.in the present investigation, it has been demonstrated that cattle become resistant to ticks after several heavy infestations, particularly with b. microplus. during development of the infestations, antibodies against salivary glands of b. microplus were detected using 2 techniques: indirect immunofluorescence and immunoelectrophoresis. there is a positive causal relationship between antibody titer and resistance development. two precipitating systems against b. microplus in infested cattle and ...197613630
the selection of larvae of boophilus microplus infected with babesia bovis (syn b argentina).observations on the dynamics of the transovarial transmission of babesia bovis by boophilus microplus showed that, at 28 degrees c and 90--95 per cent relative humidity, a low proportion of the eggs laid during the first five days' incubation of the engorged female ticks were infected with the babesia. however, the eggs laid on the sixth and seventh days of incubation were heavily infected. this was the basis of a method for selecting larval cultures of b microplus which contained up to five tim ...1977905646
formamidine acaricides: toxicological studies with the cattle tick. 1975773643
pathobiology of borrelia theileri in the tropical cattle tick, boophilus microplus. 1978731072
a comparison of the effect of two regimens of infestation on the development of resistance by cattle to the cattle tick, boophilus microplus (can.).the development of resistance to boophilus microplus by cattle was studied using sets of cattle twins, in stalls. one twin from each set received 3 infestations of 40,000 larvae and the other a continuous infestation of 1,000 larvae a day over the same period. sets of twins were then challenged with 1,000 larvae a day for 40 days and 2 field infestations of 20,000 larvae. correlations of ranking for resistance made at 40-day periods during daily infestations of 1,000 larval ticks or for correspo ...1976944256
the effect of density on the survival of boophilus microplus on previously unexposed cattle. 1978730467
antibody to a recombinant merozoite protein epitope identifies horses infected with babesia equi.horses infected with babesia equi were previously identified by the presence of antibodies reactive with a merozoite surface protein epitope (d. p. knowles, jr., l. e. perryman, l. s. kappmeyer, and s. g. hennager. j. clin. microbiol. 29:2056-2058, 1991). the antibodies were detected in a competitive inhibition enzyme-linked immunosorbent assay (ci elisa) by using monoclonal antibody 36/133.97, which defines a protein epitope on the merozoite surface. the gene encoding this b. equi merozoite epi ...19921280648
use of high-performance liquid chromatography to separate very small quantities of radio-labelled metabolites from biological tissue.in order to study the absorption, metabolism and tissue distribution of chemicals in cattle ticks amblyomma variegatum, a method of separating and recovering metabolites in picogram quantities was required. a high-performance liquid chromatographic system has been investigated for this purpose, using tritium-labelled amitraz and some potential metabolites. separation was carried out on nucleosil 5 mum no2 bonded phase. interchangeable pre-columns were used to extend the range of compounds which ...1977914943
linkage and dominance characteristics of genes for resistance to organophosphorus acaricides and allelic inheritance of decreased brain cholinesterase activity in three strains of the cattle tick, boophilus microplus.resistance to the organophosphorus acaricides diazinon, dimethoate and formothion in the biarra (b), mackay (m) and ridgelands (r) strains respectively of the cattle tick b. microplus has been shown previously to be controlled in each strain by a single incompletely dominant autosomal genetic factor. a very similar mode of inheritance of fenthion resistance in strain b has now been demonstrated with no departure in degree of dominance of resistance from the mean value of +0-57 common to these st ...1976985225
biochemical genetics of resistance to organophosphorus acaricides in three strains of the cattle tick, boophilus microplus.three aspects of the biochemical genetics of resistance to organophosphorus compounds in the biarra (b), mackay (m) and ridgelands (r) strains of the cattle tick b. microplus were studied. these were: decreased acetylcholinesterase (ache) activity in adult brains of strains b and m; decreased ache sensitivity to inhibitors in adult brains and in larvae of strains b, m and r; and increased detoxication in larvae and adult females of strain m. comparisons were made with a susceptible reference str ...1976985226
factors affecting the detection of infestations of boophilus microplus in tick control programs.factors affecting the probability of detecting infestations of boophilus microplus when herds of cattle are examined were studied. the probability of detecting a tick depends on the number of infested cattle in the herd, the probability of ticks being present on the areas of the beast examined, the efficiency of the examination and the proportion of the herd examined. a mathematical expression relating these factors was derived, and a range of values calculated to demonstrate the relative import ...1976985247
isolation and partial characterization of an antigen from the cattle tick, boophilus microplus. 1976955670
aniline metabolism in two species of arachnida: water-soluble metabolites.1. the metabolism of [14c]aniline in the cattle tick, boophilus microplus (canestrini) at 40 and 300 mug per animal) and in the spider, nephila plumipes (at 40 mug per 100 mg) were studied. 2. in both species hydroxylation occurred yielding both free and conjugated o-and p-aminophenols. 3. the water-soluble metabolites affording aniline on acid hydrolysis were examined, and gamma-glutamylanilide (23% of dose) was identified as a tick metabolite (40 mug dose). this metabolite was not found in ext ...1976983127
african cattle tick infesting a canadian. 1976953925
infection rates and outbreaks of disease due to babesia argentina in unvaccinated cattle on 5 beef properties in south-eastern queensland.serums from unvaccinated groups in 5 herds of beef-cattle in south-east queensland were tested for antibodies to babesia argentina at intervals while the cattle were increasing in age from about 6 months. an indirect fluorescent antibody test was used. infection rates, indicating the proportions of the groups that had been exposed to tick-transmitted infection were 49.2, 56.9 and 69.1% for cattle aged approximately 6, 12 and 18 months, respectively. the degree to which cattle were infested with ...19761016134
stimulation of the development of infective babesia bovis (= b. argentina) in unfed boophilus microplus larvae. 19761016162
boophilus microplus: the effect of host resistance on larval attachments and growth.growth and behaviour of boophilus microplus larvae on british breed cattle, with different resistance levels to the tick, were studied to elucidate the nature of resistance. on highly resistant animals, larval growth rate was slower for the first 3 days, but by day 4 they had attained the normal weight and the majority were subsequently able to moult. using phosphorus-32 labelled larvae, it was found that attachment times were shorter and more time was spent wandering on highly resistant animals ...1976987568
antigonadotropic action of insect hormone analogues on the cattle tick boophilus microplus. 1977576494
light and electron microscopic observations on the development of small merozoites of babesia bovis in boophilus microplus larvae.the development of small pyriform merozoites of b. bovis in the granule-secreting cells of the salivary glands of b. microplus larvae, studied with a light microscope, showed a close resemblance to that of b. argentina described by riek (1966) in the same tick vector. dvelopment took place through a process of schizogony and resulted in the formation of many merozoites. a study of the ultrastructure of developing merozoites in the schizont revealed the following: a poorly defined outer membrane; ...19761012651
boophilus microplus: cellular responses to larval attachment and their relationship to host resistance.the histology of early feeding lesions of the cattle tick b. microplus has been studied using 32p labelled larvae to standardize the duration of attachment. critical studies were made on 3-h lesions in six separate experiments on different groups of british breed animals. each group consisted of three animals--one previously unexposed to ticks, one of high resistance and one of low resistance. the degree of mast cell disruption, eosinophil concentration and degranulation, and the extent of epide ...19761023863
boophilus microplus: characterization of enzymes introduced into the host.a number of enzymes, presumably secreted by larvae of b. microplus under natural feeding conditions, have been investigated in the skin of previously unexposed calves 4 h after infestation at the attachment site. carboxylic ester hydrolase activity was demonstrated in the dermis, immediately adjacent to the mouthparts, or in the attachment cone, depending on substrate and reaction ph. the carboxylic ester hydrolase acting on naphthol as-d acetate (2-acetoxy-3-naphthoic-o-toluidide) at ph 7-1 was ...19761023862
eradication of boophilus microplus (acari: ixodidae) in puerto rico.the ongoing cooperative effort between the united states department of agriculture, animal and plant health inspection service and the puerto rico department of agriculture to eradicate the southern cattle tick, boophilus microplus (canestrini), is reviewed. epidemiological and biological aspects of the tick that influence efficient control and/or eradication in puerto rico are discussed. the differences between the current eradication methodology and that initially utilized by the program are e ...19921626894
biology and transmission of babesia bigemina in boophilus microplus. 19921626891
a comparative toxicological and biochemical study of the effects of coumaphos on larvae of haemaphysalis longicornis and boophilus microplus. 19761052884
feeding of boophilus microplus larvae on a partially defined medium through thin slices of cattle skin.larvae of the cattle tick boophilus microplus will attach to thin (0-3--0-5 mm) slices of cattle skin and engorge on a partially defined medium at 35 degrees c. forty-seven to 83 per cent of the larvae had engorged by 8 days, and 51--71 per cent of these moulted to nymphs. tissue culture medium alone allowed little growth unless supplemented with dialysed, freeze dried bovine serum (7 per cent, w/v). this medium could be further difined by substituting purified bovine serum albumin (cohn frac ...19751128926
resistance to boophilus microplus (canestrini) in genetically different types of calves in early life.tick resistance and blood composition were studied in british (1/2 shorthorn x 1/2 hereford) and zebu (1/2 brahman x 1/2 british) calves from birth to 33 days of age in a tropical grazing area in which b. microplus is endemic. calves of the 2 breeds were either naturally infested or were, in addition, artificially infested with 5,000 larvae at 2 and 9 days of age. total numbers of mature female ticks carried from either type of infestation were significantly lower (p less than 0.01) on zebu than ...19761263044
saliva-activated transmission (sat) of thogoto virus: dynamics of sat factor activity in the salivary glands of rhipicephalus appendiculatus, amblyomma variegatum, and boophilus microplus ticks.thogoto (tho) virus is transmitted from infected to uninfected ticks when co-feeding on uninfected guinea-pigs, even though the guinea-pigs do not develop a detectable viraemia. this form of non-viraemic transmission is potentiated by a factor(s) secreted by the saliva of ticks and hence has been termed saliva-activated transmission (sat). the synthesis of the sat factor by the salivary glands of three ixodid tick species was determined by placing uninfected nymphal ticks on guinea-pigs that wer ...19921326431
enzymes in saliva from four parasitic arthropods.enzyme assays and sds polyacrylamide gel electrophoresis were carried out on saliva and in some cases homogenates of salivary gland and gut from four parasitic arthropods (the cattle tick, boophilus microplus (canestrini); the mosquito, aedes aegypti (l.); non-parasitic adult and parasitic larval blowfly of sheep, lucilia cuprina (wiedemann); the buffalo fly, haematobia irritans exigua de meijere). saliva from all species showed large differences in the number and molecular weight of components, ...19921330086
comparative study of tick burdens in gudali and wakwa cattle under natural infestation in the subhumid highlands of wakwa, cameroon. preliminary observations.the relative resistance to different cattle ticks of gudali and wakwa cattle with different levels of brahman breeding, grazed on natural pastures in the subhumid tropics of wakwa, cameroon, was assessed using pasture tick infestations. the basic design consisted of 5 young bulls of each breed from different sire herds. tick populations were observed in gudali and wakwa bulls over a period of four weeks when the climate was thought to be highly favourable for the free-living stages of ticks. cou ...19921339999
the level of infestation with the vector of cattle babesiosis in argentina.studies were carried out to determine the differential aptitude to sustain the only vector of cattle babesiosis in argentina, the tick boophilus microplus, throughout the infested region of this country. tick counts on bos taurus cattle were used as the main criterion to classify favourable (f), intermediate (i) and unfavourable (u) areas for its development. the geographical limits of each area were set up using data of non-parasitic tick stages, temperature, water balance and map recognition o ...19921343682
impact of babesia bovis and babesia bigemina on the production of beef cattle in uruguay.uruguay is situated in a marginal area for the development of boophilus microplus (30 degrees 35 degrees south lat.) with important areas of enzootic instability for babesia bovis and b. bigemina. the livestock products represent 70% of our exports, for which reason it is fundamental to evaluate the losses in the production that these haemoparasites cause as basic information to take future decisions. in the period 1988-1990, several works were carried out by our laboratory to know the incidence ...19921343684
detection of babesia bigemina infection: use of a dna probe--a review.the development of a repetitive dna probe for babesia bigemina was reviewed. the original plasmid (p(bbi)16) contained an insert of b. bigemina dna of approximately 6.3 kb. this probe has been evaluated for specificity and analytical sensitivity by dot blot hybridization with isolates from mexico, the caribbean region and kenya. a partial restriction map has been constructed and insert fragments have been subcloned and utilized as specific dna probes. a comparison of 32p labelled and non-radioac ...19921343692
prevalence and control of babesiosis in the americas.this review presents up-to-date information on the distribution and control measures of babesiosis in latin america. bovine babesiosis caused by babesia bovis and b. bigemia will be emphasized. the disease is endemic in most countries and poses a serious economic burden on livestock production in the region (u.s. $1365 million/year, fao, 1989). of the estimated 250 million cattle in central and south america, approximately 175 million (70%) are in tick-infested regions. humid, tropical and subtr ...19921343700
successful vaccination against boophilus microplus and babesia bovis using recombinant antigens.current methods for the control of the cattle tick boophilus microplus and the agent of bovine babesiosis, babesia bovis are unsatisfactory. effective immunological control of both parasites would have great advantages. however, naturally acquired immunity to the tick is generally unable to prevent serious production losses. a vaccine against the tick, based on a novel form of immunization, is being developed. a protective antigen has been isolated from the tick, characterized and produced as an ...19921343705
the efficacy of ethion ec (1010 g/l) against cattle ticks in morogoro, tanzania.ethion, an organophosphorus insecticide/acaricide, was found to be effective against the various cattle ticks present in morogoro tanzania after it was sprayed on cattle twice weekly for 1 year. the pre- and post-replenishment concentrations of ethion ranged between 0.04 and 0.05%. ethion was found to be stable in the spraywash. the good efficacy makes ethion a good alternative to dioxathion in tick control in tanzania.19921363176
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
effects of 60co irradiation on unfed adults and engorged females of the tick hyalomma anatolicum.unfed and engorged adults of the cattle tick hyalomma anatolicum, known to be biological vector of theileria anmulata in india, were exposed to various levels of gamma-radiation from 0-60 000 r, and the effect on engorgement and redproduction was observed. the radiation tolerance limit for unfed adults is 1000 r for engorgement and reproduction. the sterilizing dose for most of the males is 2000 r but the females can tolerate a slightly higher dose. engorged females have a tolerance limit of 10 ...19761083846
boophilus microplus (canestrini) (acaridae: ixodidae) on the bovine host. i. mortality during the developmental cycle. 19751179958
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
a specific dna probe which identifies babesia bovis in whole blood.a genomic library of babesia bovis dna from the mexican strain m was constructed in plasmid pun121 and cloned in escherichia coli. several recombinants which hybridized strongly to radioactively labeled b. bovis genomic dna in an in situ screening were selected and further analyzed for those which specifically hybridized to b. bovis dna. it was found that pmu-b1 had the highest sensitivity, detecting 25 pg of purified b. bovis dna, and 300 parasites in 10 microliters of whole infected blood, or ...19921496779
the effect of imidocarb treatment on babesia in the bovine and the tick (boophilus microplus).treatment of calves with 5 mg/kg imidocarb (3,3-1-bis-(2 - imidazolin - 2 - yl)carbanilide dipropionate) given intramuscularly 14 days before and 14 days after exposure to babesia infected boophilus microplus larvae rendered the next generation of larvae incapable of transmitting babesia infection. when administered to calves 14 or 28 days before tick exposure, the drug prevented the development of clinical babesiosis; the larval progeny of ticks reared on the calf which was treated 28 days bef ...19751129539
boophilus microplus (canestrini) (acarida: ixodidae) on the bovine host. ii. distribution of stages during development. 19751189876
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
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
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
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
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
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
new records for rhipicephalus bursa, boophilus microplus, b.decoloratus and hypoderma lineatum from libya. 19911768917
chlorodimeform and its effect on monoamine oxidase activity in the cattle tick, boophilus microplus.the action of the acaricide, chlorodimeform and its metabolite. n-desmethylchlorodimeform, on the activity monoamine oxidase (mao) from the cattle tick, boophilus microplus, were studied. both compounds were found to be potent in vitro and in vivo inhibitors of the enzyme. however the inhibition of mao does not seem to be related to the toxic action of the acaricide.19751175733
the detection of igm and igg antibodies against babesia bigemina in bovine sera using semi-defined antigens in enzyme immunoassays.soluble extracts prepared from babesia bigemina merozoites were tested for antigenicity in class-specific enzyme immunoassays currently being evaluated for the differential serodiagnosis of bovine babesiosis. intact merozoites were harvested from erythrocytes from an experimentally-infected calf by controlled hypotonic lysis and differential ultra-centrifugation. the merozoites were disrupted by ultrasonication and a crude soluble extract obtained by ultracentrifugation. fractionation of the cru ...19852413610
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
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
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
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
transstadial transmission of theileria annulata through common ixodid ticks infesting indian cattle.transstadial transmission of theileria annulata with hyalomma anatolicum anatolicum, h. dromedarii and h. marginatum isaaci, and haemaphysalis bispinosa, rhipicephalus haemaphysaloides haemaphysaloides and boophilus microplus was determined. it was found that the infection was successfully transmitted by h. a. anatolicum from larva to nymph and nymph to adult in all attempts. when larvae were fed on an infected calf the succeeding adults transmitted the infection when the intervening nymphs fed ...19751178216
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
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
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
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
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
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
observation on the composition and biosynthesis of egg wax lipids in the cattle tick, boophilus microplus.the biosynthesis of wax lipids by gené's organ, the egg waxing organ in ticks, was investigated. gené's organ, a complex dermal gland system, applies a superficial wax layer to the eggs during oviposition which prevents desiccation and is essential for egg viability. the detailed anatomy and histology of the three gland cell types are unambiguously described. serial sectioning of ticks showed that all three gland cell types are capable of contributing to the egg wax. the wax synthetic ability of ...19921638927
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
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
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
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