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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
biology and transmission of babesia bigemina in boophilus microplus. 19921626891
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
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
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
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
babesia bigemina: quantitation of infection in nymphal and adult boophilus microplus using a dna probe.candidates for a subunit vaccine against bovine babesiosis include surface proteins of infective forms found in the salivary glands of tick vectors. however, low numbers of infective forms are present within ticks and hinder analysis of this stage. to solve this problem, conditions which yield high numbers of infective forms were investigated with the use of a babesia bigemina-specific dna probe. dna from progeny of female boophilus microplus infected with b. bigemina was hybridized to probe dna ...19921730269
pathogenicity of 17 isolates of entomophagous nematodes (steinernematidae and heterorhabditidae) for the ticks amblyomma variegatum (fabricius), boophilus microplus (canestrini) and boophilus annulatus (say).entomopathogenous nematodes are well known biocontrol agents of insects. they live in the superficial layer of the soil, a location where ticks accomplish their molt and where they oviposit their eggs, making them, theoretically, the preys of infective larvae of nematodes. seventeen strains of entomopathogenous nematodes: eight strains of steinernema and nine strains of heterorhabditis were placed in contact with each of the free living stages of three tick species: amblyomma variegatum, boophil ...19937628227
the localization of a paralysis toxin in granules and nuclei of prefed female rhipicephalus evertsi evertsi tick salivary gland cells.a monoclonal antibody directed against a paralysis toxin of rhipicephalus evertsi evertsi ticks was used to localize the toxin in cytoplasmic granules and, surprisingly, chromatin of the nuclei of cells which resemble the "b" cell type in the salivary glands of rhipicephalus appendiculatus, boophilus microplus and ixodes holocyclus. the association of toxin with chromatin indicates that the toxin may have a regulatory function. evidence is provided to support the view that the toxin is made up o ...19937628232
immunity in vaccinated cattle exposed to experimental and natural infestations with boophilus microplus.gut membranes of the cattle tick boophilus microplus were extracted using a low ionic strength buffer and the soluble antigens were used to vaccinate hereford cattle. following either experimental infestation with 40,000 larval ticks or exposure to field infestation, ticks from vaccinated cattle laid 54 and 75% fewer eggs, respectively, than ticks from control cattle. after cattle were given booster injections of vaccine, and either experimentally infested with 20,000 larval ticks or exposed to ...19938225775
therapeutic and persistent efficacy of doramectin against boophilus microplus in cattle.one therapeutic and one persistent efficacy study were conducted in brazil to evaluate doramectin at a dose rate of 200 micrograms kg-1 against induced infestations of the single host tick, boophilus microplus. doramectin was highly effective in eliminating established tick populations from cattle and also in preventing infestation by the parasite. in the therapeutic study, 12 calves were infested three times a week along the dorsal line with 2500 recently hatched larvae, for a total of 11 times ...19938236733
[the cattle tick boophilus microplus (canestrini, 1888) (acarina, ixodidae)].the external morphology and life cycle of boophilus microplus--a cattle tick--were given. the control of ticks as well as host resistance to ticks were also mentioned.19938237003
native and baculovirus-expressed forms of the immuno-protective protein bm86 from boophilus microplus are anchored to the cell membrane by a glycosyl-phosphatidyl inositol linkage.a glycoprotein (bm86) from the gut cells of the cattle tick boophilus microplus, when used to vaccinate cattle, has been shown to protect cattle from tick infestation. a recombinant bm86 protein is the principal component of a novel tick vaccine currently under development. the nature of the anchorage of bm86 to tick gut epithelial cells has been investigated using bm86 from b. microplus and recombinant bm86 proteins expressed in insect cells using the baculovirus expression system. bm86 from b. ...19938269092
stagewise mortality, ovipositional biology, and egg viability of boophilus annulatus (acari: ixodidae) on boselaphus tragocamelus (artiodactyla: bovidae).the stagewise mortality, ovipositional biology, and egg viability of the cattle tick, boophilus annulatus (say), on nilgai antelope, boselaphus tragocamelus pallas, was compared with ticks reared on bos taurus (hereford) cattle. mortality was highest during the larval stage on both host species, but larval mortality on nilgai (78.6%) was significantly higher than on cattle (45.6%) hosts. mortality during the nymphal stage was also significantly higher on nilgai (49.3%) than on cattle (13.9%). du ...19938271258
localization of a low abundance membrane protein (bm86) on the gut cells of the cattle tick boophilus microplus by immunogold labeling.a preembedding immunogold technique was used to locate bm86, an antigen from the gut digest cells of the cattle tick boophilus microplus. gut from partially engorged female ticks was everted to expose the cells, lightly fixed in 4% paraformaldehyde, and then incubated in rabbit antisera against a recombinant form of bm86. following incubation in a secondary antibody conjugated to 1-nm colloidal gold, bm86 antigenic sites were visualized for both light and electron microscopy using silver enhance ...19938277383
the camel, camelus dromedarius, as a host of the cattle tick, boophilus microplus. 19938368973
the nucleotidase of boophilus microplus and its relationship to enzymes from the rat and escherichia coli.boophilus microplus contains a nucleotidase-like enzyme which is able to hydrolyze a range of nucleoside 5'-mono-, di- and triphosphates to the nucleoside. its relationship to several other nucleotide hydrolyzing enzymes has been explored. limited peptide sequencing shows similarities to both mammalian nucleotidases and the escherichia coli uridine diphosphate sugar hydrolase. the tick enzyme also hydrolyzes udp-glucose, though by a mechanism different to that of the bacterial enzyme. on the oth ...19938387372
inhibition and recovery of tick functions in cattle repeatedly infested with boophilus microplus.six tick-naive male hereford calves were infested with about 18,000 boophilus microplus larvae, 400 in a cloth bag, once a month for 6 mo. working with the bag ticks, 12 tick characteristics were recorded for each infestation. manifestations of resistance to some attributes appeared by the second infestation, peaked by the third (detachment weight, egg weight, fertility index) or fourth (feeding length, start of oviposition), and vanished by the fifth or sixth. resistance to corpse weight, ovipo ...19938410542
effects of cattle tick (boophilus microplus) infestation on the bovine immune system.the immunosuppressive effect of experimental boophilus microplus infestation on bovine peripheral blood lymphocytes (pbl) and on host antibody production to a protein antigen (ovalbumin) was examined. boophilus microplus infestation caused a marginal decrease in the percentage of t lymphocytes in pbl, which was observed in both lightly (5000 larvae) and heavily (40,000 larvae) infested cattle, and began at the second infestation and continued until the end of the fourth infestation. the percenta ...19938493757
adhesion to and invasion of cultured tick (acarina: ixodidae) cells by borrelia burgdorferi (spirochaetales: spirochaetaceae) and maintenance of infectivity.lyme disease spirochetes, borrelia burgdorferi, interact with cultured tick cells in ways similar to those reported to occur in the vector ixodes dammini spielman, clifford, piesman & corwin. spirochete adhesion and penetration were examined using a cell line from embryos of rhipicephalus appendiculatus neumann that morphologically resembles tick gut cells, rae25. cocultivation of b. burgdorferi with these cells permitted prolonged maintenance of infectivity for hamsters. borrelial adherence to ...19938510118
evaluation of the infectivity of a vaccinal and a pathogenic babesia bovis strain from argentina to boophilus microplus.three trials were performed to test the infectivity of a vaccinal and a pathogenic strain of babesia bovis for the tick boophilus microplus. the progeny of engorged female ticks fed on calves inoculated with the pathogenic strain were able to transmit the infection to splenectomised calves (measured by the presence of the parasite in their blood and seroconversion), whereas the progeny of engorged females fed on calves inoculated with the vaccinal strain did not transmit the organisms. these res ...19938128578
host resistance in cattle tick control.cattle ticks are an important constraint on the livestock industry, particularly in tropical and subtropical areas, mainly because of the diseases they transmit and the costs of control. conventional control is by means of acaricides; although there are still serious drawbacks, these can be minimized by a strategic approach. in this review julio de castro and robin newson look at alternatives. one is to make use of the host's innate abilities. in the simplest situation, where no control measures ...199315463656
wildlife as hosts for ticks (acari) in antigua, west indies.a survey was conducted to determine the status of wild mammals and birds as hosts for amblyomma variegatum (f.) and other tick species in antigua. surveys of wild mammals and birds were conducted periodically from september 1988 through may 1991. wild mammals surveyed included the small indian mongoose (herpestes auropunctatus hodgson), norway rat (rattus norvegicus berkenhout), and house mouse (mus musculus l.), but only mongooses were surveyed intensively. larvae and nymphs of a. variegatum, l ...19948158630
some observations on mating and fertilization in the cattle tick boophilus microplus. 19948161836
observations on cattle ticks in huila province (angola).in huila province of angola, 3864 ticks were collected during a parasitological survey carried out in the rainy season from october 1990 to april 1991. the samples were collected from cattle gathered for the annual vaccination campaign against contagious bovine pleuropneumonia, anthrax and blackleg in 18 veterinary stations of six municipalities. after tick classification, the following proportions of ticks were obtained: rhipicephalus evertsi mimeticus (27.1%), amblyomma pomposum (26.4%), booph ...19948171837
high level expression of the b. microplus bm86 antigen in the yeast pichia pastoris forming highly immunogenic particles for cattle.recently, a gene coding for the bm86 tick gut glycoprotein was cloned, expressed in escherichia coli and shown to induce an immunological response in cattle to damage ticks engorging on these animals (rand et al., 1989). we report here the increased expression of the bm86 antigen from the cattle tick boophilus microplus in the methylotrophic yeast pichia pastoris. the recombinant protein was obtained with a purity higher than 95% by a procedure with a high yield. the conducted biochemical studie ...19947764729
detection of bm86 antigen in different strains of boophilus microplus and effectiveness of immunization with recombinant bm86.the control of tick populations by using conventional strategies poses several problems, including the appearance of organophosphate resistant strains, among others. the possibility of using alternative strategies such as vaccination with tick antigens has been suggested by several authors. one particular antigen (bm86) has been described and shown to be able to induce a protective immunity against the cattle tick boophilus microplus. in this paper we demonstrate by means of immunohistochemical ...19947838598
seasonal variation of ticks (ixodidae) in bos taurus x bos indicus cattle under rotational grazing in forested and deforested habitats in northwestern argentina.the seasonal occurrence of ticks infesting cattle was monitored in a bos taurus x bos indicus commercial herd fed on a combination of native grasses and annual pastures in northwestern argentina. the number of female ticks (boophilus and amblyomma) and the proportion of cattle infested with larvae and nymphs of amblyomma ticks were recorded from a sample of 15 cows in 24 visits at intervals of 21-50 days from 5 december 1986 to 24 november 1988. the cattle were maintained on native grasses in fo ...19947839563
ingestion of host immunoglobulin by three non-blood-feeding nematode parasites of ruminants.host immunoglobulin was detected in homogenates of adult worms or fourth stage larvae of haemonchus contortus, ostertagia ostertagi, o circumcincta and dictyocaulus viviparus, but not in preparasitic third stage larvae of h contortus. all the worms had been washed in detergent before being homogenised to remove any immunoglobulin adhering to the cuticle. this procedure, the concentrations of immunoglobulin detected and observations on sections of the worms stained with fluorescent anti-sheep imm ...19947871262
a protective "concealed" antigen from boophilus microplus. purification, localization, and possible function.a membrane protein that can be used successfully to vaccinate cattle against the tick boophilus microplus has been purified and characterized. the mature protein, which is referred to as bm91, has an apparent m.w. of 86,000, an isoelectric point of 4.8 to 5.2, and is glycosylated, with an affinity for lentil lectin. bm91 is of relatively low abundance, with approximately 300 to 400 micrograms being recovered from 1 kg of semiengorged adult female ticks. the protein is located largely in the sali ...19947963573
prostaglandin e2 production by the cattle tick (boophilus microplus) into feeding sites and its effect on the response of bovine mononuclear cells to mitogen.prostaglandin e2 (pge2) secretion by the cattle tick boophilus microplus into feeding sites was quantified. it was detected by the in vitro tube feeding experiment and it was determined that a semi-engorged female tick could produce and transmit 1.8 ng pge2 into the feeding site. using the in vitro membrane feeding system, newly molted adult ticks were also shown to secrete 0.04-0.15 ng pge2 into the feeding site; however, female ticks produced more pge2 than male ticks. the immune suppressive e ...19947975125
vaccines against arthropods.the possibility of vaccinating hosts against blood-feeding arthropods using antigens derived from salivary gland, gut, and other tissues is reviewed. these vaccines directed against vector arthropods also have the potential to effect the arthropods capacity to transmit pathogens, and this is distinct from transmission-blocking vaccines that use antigens derived from pathogens. antigen extracts have been used in attempts to vaccinate against fleas, lice, keds, flies, mosquitoes, and a number of t ...19948024089
babesia bovis: infectivity of an attenuated strain of brazilian origin for the tick vector, boophilus microplus.in order to verify the infectivity and transovarian transmission of one strain of babesia bovis of brazilian origin, attenuated by repeated passages in splenectomized calves to the biological tick vector, boophilus microplus, an inoculation of that strain was performed in hemoparasite-free calves infested with hemoparasite-free ticks. subsequently, engorged female ticks were collected to examine hemolymph and progeny for presence of developing stages of babesia bovis. using an optical microscope ...19948030179
tick infestations on cattle vaccinated with extracts from the eggs and the gut of boophilus microplus.extracts prepared from the membranes of eggs (em) and guts (gm) of boophilus microplus were used to immunise cattle which were then infested twice with 20,000 larval ticks 1 week apart. em antigens did not protect cattle against challenge with ticks, despite high levels of anti-egg antibodies in the sera of the vaccinated cattle, detected by an indirect enzyme-linked immunosorbent assay (elisa). cattle vaccinated with gm, however, had high levels of antibodies against gm and were protected signi ...19948030189
serum of boophilus microplus infested cattle reacts with different tick tissues.five cattle were each experimentally infested with 30,000 boophilus microplus larvae and their humoral immune response to salivary gland, gut, embryo and larval extracts during infestation were determined by enzyme-linked immunosorbent assay (elisa) and western blot analysis. serum antibodies to embryo extract were detected by elisa 21 days after infestation and antibodies to the other extracts 28 days following infestation. using western blot analysis, new bands were recognized and others disap ...19948030190
microorganisms in the development of subunit vaccines against parasites.because of the increasing problems of resistance to chemicals and chemical residues, preventative vaccination has increasing appeal as a way to control parasite infestations in humans and in animals. such vaccines are now feasible through the application of genetic engineering technology to allow production of parasite protective antigens in microorganisms in commercially viable quantities at an acceptable cost. this concept is illustrated by describing research toward subunit vaccines against h ...19948080628
quil a and iscoms as adjuvants for midgut membrane antigens of boophilus microplus.quil a used with boophilus microplus gut membrane antigen (gm) had a significant effect on antibody levels induced in sheep (p < 0.05) since gm alone did not induce a significant level of antibodies. injection of a vaccine containing gm and quil a, either subcutaneously or intramuscularly, induced similar levels of antibodies in sheep. however, quil a injected subcutaneously induced acute inflammatory reaction. the amount of quil a for use with gm was determined to be 1000 micrograms/ml. immunos ...19948087157
transmission of anaplasma marginale with adult boophilus microplus ticks fed as nymphs on calves with different levels of rickettsaemia.nine splenectomised calves were infested with dissimilar numbers of adult boophilus microplus ticks 72 h after collection as engorged nymphs from three non splenectomised calves with different levels of anaplasma marginale rickettsaemia. successful transmission of a. marginale appeared to be more dependent on the level of rickettsaemia of the donor calves than on the number of ticks attaching to the splenectomised calves, since infection was transmitted only when the rickettsaemia was 0.3% or gr ...19949140508
comparison of prostaglandin e2 (pge2) in salivary gland of boophilus microplus, haemaphysalis longicornis and ixodes holocyclus, and quantification of pge2 in saliva, hemolymph, ovary and gut of b. microplus.the amount of prostaglandin e2 (pge2) in salivary gland of semi-engorged adult female boophilus microplus, haemaphysalis longicornis and ixodes holocyclus were 374.3 pg, 427.0 pg and 825.0 pg per one tick, respectively. it was thought that the pge2 production is a common phenomenon among ticks. then pge2 concentrations in saliva and hemolymph, salivary gland, ovary and gut of fully-engorged adult female b. microplus were compared. the pge2 concentration in saliva induced by pilocarpine was 40.3 ...19947696426
host resistance to ectoparasites.examples of immunological reactions to arthropod parasites include responses by hosts to the following stimuli: excretory and secretory antigens produced by myiasis-producing larvae or skin-dwelling (mange) mites salivary antigens of blood-sucking arthropods. in many cases, these are hypersensitivity reactions, which often appear not to produce very deleterious effects on the parasites. however, some reactions--such as those induced by natural infestations with ixodid ticks and certain mange mit ...19947711313
the effects of moxidectin against natural infestations of the cattle tick (boophilus microplus). 19947726764
seasonal incidence and hemoparasite infection rates of ixodid ticks (acari: ixodidae) detached from cattle in costa rica.to determine the tick species hindering the cattle industry in costa rica and to assess infection rates of ticks with three important hemoparasite species, cattle were monitored during a period of six months (october 1992-march 1993). four farms were located in the dry pacific region of the canton of tilarán and a fifth farm on the slopes of the poás volcano in a cool tropical cloud-forest ecosystem. on each farm 3 to 5 animals of 6 to 24 months of age were selected at random. all ticks were rem ...19947501871
comparative reproduction and nonparasitic development of boophilus microplus and hybridized boophilus ticks (acari: ixodidae) under natural field conditions in subtropical south texas.the reproductive biology and nonparasitic development of boophilus microplus (canestrini) and hybridized boophilus ticks (b. annulatus (say) male x b. microplus female) held under natural field conditions in south texas throughout the year were compared. comparisons between the two types of ticks indicated that the ovipositional biology (percentage of ovipositing females and number of eggs laid) of the females favored hybrid ticks during some months and b. microplus ticks during other months. ho ...19947628244
carboxydipeptidase from boophilus microplus: a "concealed" antigen with similarity to angiotensin-converting enzyme.a protein, bm91, which was first identified as a protective vaccine antigen from the tick boophilus microplus, has regions of very strong amino acid sequence similarity to mammalian carboxydipeptidases or angiotensin converting enzymes (ace; e.c. 3.4.15.1). this protein is now shown to share many biochemical and enzymatic properties with mammalian carboxydipeptidases. it is enzymatically active in a conventional assay for ace using hippuryl-gly-gly as substrate. the hydrolysis of the c-terminal ...19958541886
acaricidal and insecticidal activities of cadina-4,10 (15)-dien-3-one.the novel assignment of 13c and 1h nmr data for cadina-4,10(15)-dien-3-one obtained from hyptis verticillata is presented. the study revealed that cadina-4,10(15)-dien-3-one possesses chemosterilant activities against the economically important cattle tick, boophilus microplus, and toxic action against adult cylas formicarius the most destructive pest of sweet potato (i pomoea sp.).19957576456
strategies for the control of one-host ticks and relationship with tick-borne diseases in south america.a variety of hemoparasites occurs in ruminants of south america (12 degrees 00'n-56 degrees 00's), but there is consensus on the significant economic impact of babesiosis (babesia bovis and babesia bigemina) and anaplasmosis (anaplasma marginale). the tick vector for the babesia spp. for the whole region is boophilus microplus which has been the most important target in control/eradication programs. boophilus microplus and many different hematophagous diptera species are considered vectors of a. ...19957597780
vector situation of tick-borne diseases in the caribbean islands.the most important ticks transmitting diseases to ruminants in the caribbean islands are: amblyomma variegatum, vector of cowdriosis and associated with acute dermatophilosis; amblyomma cajennense, potential vector of cowdriosis; boophilus microplus, vector of babesiosis and anaplasmosis. at the present time, amblyomma variegatum is widespread in the lesser antilles from barbados to puerto rico. the intensity of the tick control program varies in the different islands and the tick infestation in ...19957597781
modelling the field efficacy of a genetically engineered vaccine against the cattle tick, boophilus microplus.the cattle tick boophilus microplus canestrini (ixodidae) is an obligate parasite of bovines in the tropics. vaccination against the tick, using concealed antigens, has previously been demonstrated to give partial protection which can vary under field conditions. in this paper computer modelling is used to evaluate the potential impact of the vaccine on populations of ticks on grazing cattle. the degree and duration of protection required to maintain tick numbers at acceptable levels is investig ...19957601586
a survey of cattle producers in the boophilus microplus endemic area of queensland to determine attitudes to the control of and vaccination against tick fever.a survey by mail was used to determine the views of beef producers in the boophilus microplus endemic area of queensland on the control of and vaccination against tick fever. data from 448 questionnaires were analysed, representing 2.7% of beef producers in the survey area. producers considered buffalo fly (haematobia irritans exigua) infestation as the most important problem whereas tick fever ranked sixth overall. private veterinarians were regarded as the most important source of information ...19957611988
antigens identified by monoclonal antibodies in tissue sections of boophilus microplus.a panel of monoclonal antibodies (mabs) raised against midgut antigens of boophilus microplus were used to probe various stages and organs of the tick. one of the monoclonal antibodies in this panel (qu13) has previously been shown to recognize protective antigens. of the 18 mabs tested, all except two (qu5 and qu12) reacted with sections of adult midgut and malpighian tubules using an avidin-biotin alkaline phosphatase method for immunostaining. mabs qu1, qu2, qu3, qu4, qu12, qu13, and qu18 rea ...19957622331
relationships and influences between boophilus microplus characteristics in tick-naive or repeatedly infested cattle.six tick-naive male hereford calves were infested once a month for 6 months with 18,000 boophilus microplus larvae on the back and with 400 larvae in a cloth bag glued on the lumbar region. working with the bag ticks, 12 tick characteristics were recorded for each infestation. each tick attribute was analyzed for significant differences with those of the first infestation (analysis of variance), and for similarity (clustering), degree of relationship (correlation), and concomitant variation (reg ...19957732646
anti-idiotypic antibodies as surrogate antigens for vaccinating against the cattle tick, boophilus microplus.qu13, a monoclonal antibody (mab) raised against midgut (gm) antigens from boophilus microplus and shown to recognise antigens which protect cattle from tick challenge was used to immunise cattle and rabbits to produce anti-idiotypic antibodies (aia). polyclonal antisera against mab qu13 were produced in rabbits and cattle. aia were purified from these antisera by affinity chromatography procedures. these purified aia were found to block mab qu13 binding to gm in enzyme-linked immunosorbent assa ...19957754608
tick resistance to pyrethroids in new caledonia.boophilus microplus is the common cattle tick of great economic importance in new caledonia. since 1986, deltamethrin has been used for dipping. in 1992, an increase of tick infestations was seen on some ranches. field and laboratory studies were conducted to determine if resistant ticks were present. ticks resistant to deltamethrin were detected on three ranches, with resistance factors from 8.3 to 97.7. all deltamethrin-resistant isolates were also resistant to fenvalerate, but only one was al ...19957754609
experimental studies of the rate of infection of boophilus microplus eggs with babesia bovis.babasia bovis infection in the eggs of boophilus microplus was investigated by examining the total output of eggs by 10 engorged female ticks with a level of haemolymph infection with b bovis ranging from 0.2 to 20.6 kinetics per microscope field. the ticks were fed on infected calves, with a parasitaemia ranging from 0.01 per cent to 0.02 per cent, inoculated with a stabilate of b microplus larvae containing the protozoa. infected eggs, 9.5 per cent of the total eggs laid, were detected from th ...19957659857
control of boophilus microplus populations in grazing cattle vaccinated with a recombinant bm86 antigen preparation.current methods for the control of cattle tick boophilus microplus infestations are not effective and the parasite remains a serious problem for the cattle industry in tropical and subtropical areas. recently, we developed a vaccine against b. microplus employing a recombinant bm86 (rbm86) antigen preparation (gavac, heber biotec) and it was shown to induce a protective response in vaccinated animals under controlled conditions. here we show that, under field conditions in grazing cattle, the va ...19957660571
infection dynamics of babesia spp. kinetes in naturally infected, engorged, female boophilus microplus. 19957668923
epidemiological aspects of equine babesioses in a herd of horses in brazil.epidemiological studies of babesia equi and b. caballi were undertaken in a herd of 120 pastured horses in rio de janeiro, brazil. the area where the horses were held was shown to be highly endemic for both babesia spp., i.e. the prevalence of b. equi antibodies in horses aged 6 months or older ranged from 90.6% to 100% as determined by the immunofluorescence antibody (ifa) test, and the prevalence of b. caballi antibodies as determined by western blot ranged from 59.4% to 65.5%. from the herd, ...19957676590
the effect of various adjuvants on the humoral immune response of sheep and cattle to soluble and membrane midgut antigens of boophilus microplus.sheep and cattle were immunized with soluble and membrane midgut antigens of the cattle tick, boophilus microplus in association with various adjuvants, and antibody levels to soluble and membrane midgut extracts were measured by enzyme-linked immunosorbent assay (elisa). the adjuvants used were quil a, freund's incomplete adjuvant (fia) and aluminium hydroxide (a1(oh)3). significant antibody levels to midgut membrane antigen (gm) were not detected in the sera of sheep immunized with gm plus a1( ...19957676593
costs of major parasites to the australian livestock industries.a cost-benefit model is developed to estimate the costs of major parasites to australian livestock industries and to evaluate the benefits from improving parasite management. the model disaggregates the australian livestock industries into agro-climatic regions and various stock classes to estimate the total treatment and production loss costs of major parasites. experimental trials and a computer simulation model are used to estimate the productivity of livestock under different treatment regim ...19958635886
changing patterns of vitellin-related peptides during development of the cattle tick boophilus microplus.the major components of protein extracts from the cattle tick boophilus microplus eggs and larvae of various ages were characterized by molecular sieving chromatography, ion exchange chromatography and sds-page. the fractions analysed showed a changing chromatographic pattern development. a serum raised against the components of a fraction showing characteristics of vitellin strongly reacted in western blots with the major peptides of extracts from eggs, larvae, gut and ovary. comparison of patt ...19958521746
the effects of continuous and intermittent delivery of antigens of boophilus microplus on the development of murine antibodies.protective antigens solubilised from the membranes of the midgut (li-gm) of the adult cattle tick boophilus microplus were delivered to mice either continuously for up to 4 weeks from osmotic pumps implanted subcutaneously or intermittently in a pulsatile fashion by injections or by a combination of both modes of delivery. the effects of delivery profile on antigen specific antibody levels and avidity were compared. li-gm delivered either by three injections (weeks 0, 2 and 4), or continuously f ...19958533285
acid phosphatase in midgut digestive cells in partially fed females of the cattle tick boophilus microplus.enzyme cytochemistry was used to identify vesicles containing acid phosphatase in the midgut digestive cells of partially fed females of the cattle tick boophilus microplus. the vesicles were elongated or tubular in shape and appeared to be involved with the digestion of host bloodmeal. in mature cells, they were sometimes in close contact with large endosomes, which contained host blood. the vesicles were identified as tubular lysosomes because their morphological and cytochemical characteristi ...19957776118
commercialisation of a recombinant vaccine against boophilus microplus.increasingly, there is need for methods to control cattle tick (boophilus microplus) infestations by the use of non-chemical technology. this need is brought about by a mixture of market forces and the failure or inadequacy of existing technology. a recombinant vaccine has now been developed against the tick. this vaccine relies on the uptake with the blood meal of antibody directed against a critical protein in the tick gut. the isolation of the vaccine antigen, bm86, and its production as a re ...19957784128
efficacy of injectable doramectin against natural boophilus microplus infestations in cattle.three experiments were conducted in latin america--1 in brazil, 1 in venezuela, and 1 in argentina--using a common protocol to investigate the efficacy of a single sc injection of doramectin (200 micrograms/kg of body weight) for treatment and control of boophilus microplus infestations in grazing cattle. in each experiment, 2 groups of 20 to 27 cattle were allocated on the basis of tick burdens present 24 hours before treatment to a treated or control group, which received saline solution (1 ml ...19957785822
studies on the morphological changes in the midguts of two ixodid tick species boophilus microplus and rhipicephalus appendiculatus during digestion of the blood meal.light and electron microscopy were used to study the morphological changes which accompanied feeding and digestion of the blood meal in the midgut epithelium of two ixodid tick species boophilus microplus and rhipicephalus appendiculatus. in unfed ticks of both species, the midgut epithelium was lined by stem cells and empty digest cells in which haematin accumulated with starvation. on attachment to its hosts, differentiation of the stem cells and the loss of haematin from the midgut epithelium ...19957797373
effect of vaccination with a recombinant bm86 antigen preparation on natural infestations of boophilus microplus in grazing dairy and beef pure and cross-bred cattle in brazil.current methods for the control of the cattle tick boophilus microplus infestations are not effective and the parasite remains a serious problem for the cattle industry in tropical and sub-tropical areas. recent advances have introduced the possibility for the immunological control of the parasite through the use of recombinant vaccines. recently, it was shown that the recombinant vaccine gavac (heber biotec s.a.) is able to control b. microplus populations in artificially infected grazing dairy ...19958701597
light microscopy diagnosis of babesia bovis and babesia bigemina kinetes in the haemolymph of artificially infected boophilus microplus engorged female ticks.the length, width and position of the nucleus of babesia bovis and babesia bigemina kinetes from the haemolymph of boophilus microplus engorged female ticks were recorded. additionally, the shape of babesia bovis kinetes were registered as curved, semi-curved or straight. to this aim boophilus microplus tick larvae from a colony free of babesia were fed on splenectomised calves artificially infected with either babesia bovis or babesia bigemina pathogenic strains. six engorged female ticks showi ...19968750679
morphology and development of anaplasma marginale in midgut of engorged female ticks of boophilus microplus.morphology and development of anaplasma marginale were studied in midgut epithelial cells of adult boophilus microplus females using light and transmission electron microscopy. hemoparasite-free b. microplus larvae were used to infest holstein calves experimentally inoculated with a. marginale. when a. marginale parasitemia varied from 0.4% to 4.3%, 140 engorged female ticks were collected and kept individually in steel wire tubes and incubated outdoors on brachiaria decumbens grass pasture. fem ...19968750681
incidence and intensity of babesia spp. sporokinetes in engorged boophilus microplus from a dairy herd in venezuela.the objective of this study was to determine the incidence and intensity of babesia spp. sporokinetes in hemolymph of engorged females (ef) boophilus microplus monthly detached from two herds of a local dairy breed of cattle named carora breed. the experimental herds were located in 2 ranches, 45 km apart, having different management of tick control (tc). proper methods of tc were commonly used at ranch "a," whereas ineffective methods were used at ranch "b," babesia spp. sporokinetes were diagn ...19968784496
age and weight relationship in boophilus microplus (ixodoidea: ixodidae) larvae.the study of the age of free-living stages of ticks is not a frequent subject in acarology research. baseline knowledge and some possible applications both in research and in tick control are to be considered. sixty engorged females were incubated at 28 +/- 1 degrees c and 100% relative humidity. age zero of larvae was established at 10 days after the beginning of eclosion. larvae were weighted in paper envelopes in groups ranging from 150 to 400 each. live weight means (lwm) and dry weight mean ...19968784504
light microscopy diagnosis of babesia bovis and b. bigemina kinetes in the hemolymph of artificially infected boophilus microplus engorged female ticks. 19968784530
immunological cross-reactivity between salivary gland proteins of hyalomma anatolicum anatolicum and boophilus microplus ticks.immunological cross-reactivity was established between salivary gland extract antigens of hyalomma anatolicum anatolicum (h.a.a) and boophilus microplus (b.m.), using native-polyacrylamide gel electrophoresis (native-page), immunoblotting, dot-enzyme immunoassay (dot-eia) and in vivo intra-dermal skin test revealing immediate type hypersensitivity swelling reaction. native-page revealed six proteins in common of molecular weights of 60, 66, 148, 264, 300 and > 300 kda in the salivary gland extra ...19968792571
formulation of integrated control of boophilus microplus in paraguay: analysis of natural infestations.a 3-year study into the seasonal variation in the numbers of boophilus microplus ticks infesting three breeds of beef cattle in paraguay was carried out to provide the basic data necessary to formulate tick control recommendations. the effect of tick burden on weight gain was also analysed. economic parameters for tick control were calculated. half body counts of standard female b. microplus were carried out every 2 weeks, at the same time engorged female ticks were placed in the field to observ ...19968792584
simulation of control strategies for the cattle tick boophilus microplus employing vaccination with a recombinant bm86 antigen preparation.current strategies for the control of the cattle tick boophilus microplus include the use of chemicals as the principal control method. these methods, however, have met with partially successful results. the recent development of immunological methods for the control of the cattle tick has opened new possibilities for the design of control strategies. employing the results obtained by us in experiments testing the effect of vaccination with the recombinant vaccine, gavac (heber biotec s.a.), on ...19968792587
the efficacy of amitraz against cattle ticks in tanzania.the efficacy of amitraz on cattle ticks was assessed by susceptibility tests, spraying and dipping trials. tests on the susceptibility of three tick species, rhipicephalus appendiculatus, amblyomma variegatum and boophilus decoloratus to amitraz (technical grade-purity 98.6% w/w) showed all 15 tick strains tested to be highly susceptible, with lc50 ranging between 0.001% and 0.03%, and lc99, between 0.01% and 0.07%. spraying trials were carried out on calves infested with r. appendiculatus, a. v ...19968856759
biochemical characterization of the recombinant boophilus microplus bm86 antigen expressed by transformed pichia pastoris cells.in the present paper we report the biochemical characteristics of the recombinant tick (boophilus microplus) gut antigen bm86 that previously has been cloned, expressed and recovered at high levels in the methylotrophic yeast pichia pastoris. the results demonstrate that rbm86 had a modification at position 92 (thr replaced by ile) and aggregated, forming particles ranging between 17 and 40 nm. the rbm86 was n-glycosylated, having at least two non-glycosylated sequons (asn-329 and asn-363) and a ...19968867893
endocytosis by digest cells of the cattle tick boophilus microplus: regulation by protein kinase c.endocytosis of fluorescently-labeled bovine serum albumin by digest cells of the gut of the cattle tick boophilus microplus is inhibited by approx 60% in the presence of the tumour promoter 12-o-tetradecanoylphorbol 13-acetate. the results are consistent with a role for protein kinase c in regulating the uptake of blood meal by digest cells. protein kinase c activity has been measured in the digest cell and the amount of enzyme has also been determined using a phorbol ester binding assay. the pr ...19968882657
vaccination against worm parasites of animals.the 1990s have seen the culmination of decades of painstaking research with the registration and launch of tickgard (hoechst), a recombinant vaccine against boophilus microplus, and the provisional registration of a taenia ovis vaccine. research continues to hold promise for immunological control of echinococcus, fasciola, haemonchus, trichostrongylus and ostertagia. blood-sucking parasites (e.g. ticks and h. contortus) are susceptible to control by vaccines containing 'novel' or 'concealed' ant ...19968893462
integrated tick and tick-borne disease control trials in crossbred dairy cattle in malawi.crossbred dairy heifers on a farm in an east coast fever (ecf) endemic area in malawi were immunised against theileria parva, anaplasma spp., babesia bigemina, babesia bovis and cowdria ruminantium. they were treated at infrequent intervals with chlorfenvinphos to limit infestation with adult ticks, without providing complete tick control. in one trial, which tested a threshold dipping regimen, 20 heifers were dipped only once in 6 months to control a flush of boophilus microplus. unimmunised co ...19968983132
uniformity of protective antigens among isolates of the cattle tick, boophilus microplus.gut membrane antigens were extracted from ten isolates of the cattle tick boophilus microplus; the antigen extracts were probed with bovine antisera and three murine monoclonal antibodies (mabs) in western blots and dot-elisa. the antisera had been obtained from cattle which were vaccinated with larval and gut extracts of b. microplus, and which were subsequently protected (84% and 94% respectively) against challenge with b. microplus. one of the mabs (qu13) has been demonstrated to precipitate ...19968994130
suppression of boophilus microplus populations with fluazuron--an acarine growth regulator. 19969006870
[vaccines against parasitic diseases of domestic animals].this review presents short information on the present status and some future perspectives of vaccination against parasitoses of domestic animals. for the control of such parasitoses in some european countries only a few vaccines are registered: paracox and livacox (for coccidiosis in chickens), toxovax (for toxoplasmosis in sheep), pirodog (for babesiosis in dogs) and dictol (for dictyocaulosis in cattle). these are live vaccines containing attenuated parasites, except pirodog. as a world-wide i ...19969012013
the history of the cattle tick boophilus microplus in australia and achievements in its control.for more than 100 years, tick fever and the cattle tick have caused tremendous financial loss to cattle producers around the world. since australia became infected with the disease and infested with its tick vector in the mid-19th century, a great deal of research effort has been directed towards their effective control by australian farmers, administrators and scientists. such research has yielded information which has facilitated the development of various control strategies that have equal ap ...19969024884
boophilus microplus: multiple proteolytic activities in the midgut. 19968617328
functional bovine immunoglobulins in boophilus microplus hemolymph.the aim of the present work was to quantify the passage of bovine immunoglobulins into the hemolymph of the tick boophilus microplus during the feeding process and to determine their antibody activity. the knowledge is of paramount importance when vector control or blocking of disease transmission is attempted by vaccination of cattle. approximately 2% of bovine immunoglobulin present in the serum as determined by competitive elisa was demonstrated in hemolymph of b. microplus and antibody activ ...19968638388
catabolism of dopamine and 5-hydroxytryptamine by monoamine oxidase in the ixodid tick, amblyomma hebraeum.the purpose of this study was to assess biogenic amine catabolism in amblyomma hebraeum koch (an african cattle tick). we assayed haemolymph and saliva for a variety of biogenic amines (usually following injection of substrate into the haemolymph) in partially fed females using hplc coupled to electrochemical detection. dopamine (da) and 5-hydroxytryptamine (5-ht) were rapidly converted to dihydroxyphenylacetic acid (dopac) and 5-hydroxyindoleacetic acid (5-hiaa) respectively, indicating that mo ...19968673075
comparative vaccination of cattle against boophilus microplus with recombinant antigen bm86 alone or in combination with recombinant bm91.cattle were vaccinated either with a single recombinant tick antigen, bm86 or with a combination of two recombinant antigens, bm86 and bm91 from the tick boophilus microplus. in three experiments, the responses of cattle to subsequent challenge with the tick were assessed. the addition of the bm91 antigen enhanced the efficacy of the vaccination over that with bm86 alone to a statistically significant degree. moreover, co-vaccination with two antigens did not impair the response of cattle to the ...19969229376
feeding of hard ticks in vitro: new perspectives for rearing and for the identification of systemic acaricides.experiments on in vitro feeding of the hard ticks ixodes ricinus, boophilus microplus, amblyomma variegatum and amblyomma hebraeum are described. an in vitro test for systemic acaricides is presented. work started with a feeding chamber continuously supplied with new blood. it proved too susceptible to fungal contamination and not efficient enough. simple feeding units made of honey jars with an inner glass tube were far more practical. reinforced silicone membrances or baudruche membrances impr ...199611178446
[insects know no border.].one of the major consequences of the joined action of demographic pressure and evolution of human activities lies in enormous increase of transportation, both in frequence and speed; taking advantage of these facilities, some arthropods could increase their geographical distribution and create new health threats. several demonstrative examples are exposed in order to illustrate this anthropic dissemination of the vectors : the introduction of anopheles gambiae s.l. in mauritius island between 18 ...199617292311
lectin activity from the cattle tick (boophilus microplus) saliva.the capability of boophilus microplus saliva (bms) and lectins to induce immunosuppression in mice and to agglutinate erythrocytes from distinct animal species were compared. cd-1 mice were distributed into groups (two for each substance) of 4-5 animals/group and treated intraperitoneally (i.p.) with 50 mg and 150 mg of bms; concanavalin a (con a); potato's lectin (pl), striped bean lectin (sbl) or 0.1 ml of phosphate buffered saline (pbs). all mice were immunized i.p. with 2 x 108 sheep erythro ...199710932717
cross-sectional estimation of babesia bovis antibody prevalence in an area of argentina used for extensive cattle breeding as an aid to control babesiosis.the prevalence of babesia bovis antibodies was estimated by using an elisa (98% sensitivity and 95% specificity). sera were obtained from 165 calves (mean age and standard deviation: 9.7 +/- 2.7 months) from an area in argentina known to be unfavourable for the development of the vector tick, boophilus microplus. the area comprised about 300,000 ha used for cattle breeding. the cattle population of 55,000 included 12,000 cattle under 1 year of age. cattle were maintained mainly on natural grasse ...19979234418
antibody-mediated inhibition of the growth of larvae from an insect causing cutaneous myiasis in a mammalian host.many insects feed on blood or tissue from mammalian hosts. one potential strategy for the control of these insects is to vaccinate the host with antigens derived from the insect. the larvae of the fly lucilia cuprina feed on ovine tissue and tissue fluids causing a cutaneous myiasis associated with considerable host morbidity and mortality. a candidate vaccine antigen, peritrophin 95, was purified from the peritrophic membrane, which lines the gut of these larvae. serum from sheep vaccinated wit ...19979256413
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