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the immune responses to antigenic variants of babesia bigemina in the bovine.four babesia bigemina stabilates were used to determine the immune response of cattle to acute and chronic blood- and tick-borne infections. thirty-two intact calves were divided into 16 groups of two and each calf was inoculated with infective b bigemina erythrocytic stabilates. twenty-eight days later they were challanged with homologous and heterologous stabilates, and monitored for an additional 20 days. the hosts' apparently reduced response to homologous challenge but marked immune respon ...197877539
tick-borne diseases of domestic animals in northern nigeria. ii. research summary, 1966 to 1976.during the first 10 years of its existence, the department of parasitology and entomology of the faculty of veterinary medicine, ahmadu bello university in zaria, nigeria, confirmed or described for the first time the occurrence of 25 different tick-borne parasites of domestic animals in the northern part of the country. most of these organisms occur as inapparent infections but may serve as complicating factors in any adverse host condition. the transmission of babesia bigemina by boophilus dec ...1977339447
electron microscopic detection of initial and some subsequent developmental stages of babesia bigemina in salivary glands of ticks. 1979433387
pentamidine in chemoimmunisation of cattle against babesia bigemina infection.a single dose of 0.5 to 1 mg/kg of pentamidine led to clinical recovery of splenectomised calves infected with babesia bigemina. on the other hand as much as 5 mg/kg administered during patency did not destroy the carrier state in intact calves. the fact that the sterilising dose was at least five times as great as that needed for clinical recovery makes pentamidine a promising agent for chemoimmunisation against b. bigemina infection.1979442205
experimental studies on the pathogenicity of babesia bigemina in buffalo calves. 1979462563
preliminary observations on the combined use of imidocarb and babesia blood vaccine in cattle.imidocarb was used by three different methods to control reactions in cattle induced by a babesia blood vaccine produced in south africa. simultaneous administration of 0,15 mg/kg imidocarb and babesia bovis vaccine gave satisfactory control. when the vaccine was given seven days prior to the imidocarb treatment a dose between 0,15 mg/kg and 0,6 mg/kg imidocarb was required for effective control. a combined b. bovis and babesia bigemina vaccine given at 21 and again 61 days after a 3 mg/kg imido ...1979553972
light and electron microscopic observations on the development of babesia bigemina in larvae, nymphae and non-replete females of boophilus decoloratus.in boophilus decoloratus infected by transovarian passage with b. bigemina, primary schizogony occurred as a continuous repetitive process in all 3 stages of the tick's life cycle spent on the host. the primary schizonts and the large merozoites (= vermicules) produced by them were observed in the gut epithelium, haemocytes, muscles, ad peritracheal cells. secondary schizogony which led to the formation of small merozoites (= infective forms) occurred mainly in the salivary glands, but was also ...1977613293
the fine structure of intra-erythrocytic stages of babesia bigemina.the electron microscope was used to study the structure of merozoites, merozoites in the process of transformation to trophozoites, trophozoites, and the method of multiplication of b. bigemina. the merozoites were piriform in shape and surrounded by 3 peripheral membranes of which the 2 inner ones often appeared as a single thick osmiophilic structure (inner membrane). anterior and posterior polar rings, microtubules, micronemes, rhoptries and mitochondria with and without tubular cristae were ...1977614533
efficacy of attenuated anaplasma marginale vaccine under laboratory and field conditions in colombia.four-month-old holstein-friesian calves were inoculated with 3 different doses (1, 2, and 3 ml) of attenuated anaplasma marginale vaccine. vaccinated calves showed mild anaplasma parasitemia, slight decrease in packed cell volume, low serologic conversion, and no clinical illness. an artificial challenge exposure of vaccinated and unvaccinated calves with virulent colombian a marginale showed that the vaccine provided protection against clinical signs of the disease, including parasitemia and an ...1978629456
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
transmission of babesia bigemina by transfer of adult male boophilus microplus. 1978687283
the extraction of infective babesia bovis and babesia bigemina from tick eggs and b. bigemina from unfed larval ticks. 1978743062
comparison of indirect fluorescent antibody (ifa) with complement fixation (cf) tests for diagnosis of babesia spp infections in colombian cattle.a total of 372 serum samples were collected from colombian cattle before and during the course of natural babesia spp. infection on the north coast of colombia. the serum samples were used to compare indirect fluorescent antibody (ifa) with complement fixation (cf) tests for diagnosis of babesiosis. the ifa technique detected babesia argentina antibodies an average of 4.0 weeks earlier than the cf test and babesia bigemina an average of 2.5 weeks earlier. both ifa and cf were capable of differen ...1976781955
antigenic variation of babesia bigemina.the purpose of the study was to determine whether antigenic differences occurred in four stabilates of babesia bigemina derived from a single purified isolate and propagated as acute and chronic, blood-borne and tick-borne infections in colombian cattle. antigens were characterised by means of the complement fixation (cf), gel diffusion (gd), agar gel electrophoresis (age) and the indirect haemagglutination tests (iha). differences were detected. acute blood and chronic blood antigens were simil ...1977905655
tick-borne diseases of domestic animals in northern nigeria. i. historical review, 1923-1969.information on the occurrence of tick-borne diseases of domestic animals in northern nigeria for the period 1923 to 1966 is summarised. due to lack of obvious outbreaks and diverse interest of the veterinary staff, the published information is very scanty. significant for the period under review was the complicating factor of babesia bigemina infections in cattle undergoing rinderpest immunisation procedures or suffering from trypanosomiasis. tick-borne diseases were also considered important in ...1977910300
babesia bigemina, babesia argentina, and anaplasma marginale: coinfectious immunity in bovines. 19751123013
studies on imidocarb dihydrochloride in experimental babesia bigemina infection in calves. 19751212605
susceptibility of boran cattle to experimental infections with anaplasma marginale and babesia bigemina. 19751217278
letter: prenatal babesia bigemina infection in a calf. 19751220660
piroplasmosis in buffaloes and its serological diagnosis based on a homology between buffalo and bovine immunoglobulins.babesia argentina, babesia bigemina and theileria mutans were transmitted experimentally from water buffaloes (bubalus bubalis) to splenectomised bos taurus calves. buffaloes were positive to an indirect fluorescent antibody test for b. argentina when reagents of bovine origin were used. the formation of similar patterns during immunoelectrophoresis suggested a homology of buffalo and bovine serum proteins, particularly igg.19761267733
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
new methods for the diagnosis of babesia bigemina infection.accurate diagnosis of babesia bigemina infection, an economically important tick-transmitted protozoan parasite of cattle, is essential in the management of disease control and in epidemiological studies. the currently used methods of diagnosis are blood smear examination and serological tests which include agglutination and immunofluorescence tests. these tests have been used in the fild but because they lack sensitivity and specificity, newer and improved methods of diagnosis are being develop ...19921343691
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
babesia bovis: bovine helper t cell lines reactive with soluble and membrane antigens of merozoites.babesia bovis-specific t cell lines were established from cattle infected with either tick-derived or cultured parasites by stimulation of peripheral blood mononuclear cells with a crude parasite membrane fraction. induction and enrichment of cd4+ t cells occurred over time. all cell lines responded vigorously and in a dose-dependent, mhc-restricted manner to intact merozoites, and to soluble and membrane fractions derived from merozoites by homogenization and high-speed centrifugation. solubili ...19921371257
studies on the pathological changes in babesia bigemina infection in indigenous cow calves. 1977910588
haematological reactions to experimental babesia bigemina infection in splenectomised and non-splenectomised cattle. 1977888605
the effect of natural exposure to anaplasma and babesia infections on native calves in an endemic area of colombia.the age at which native calves first became infected with anaplasma marginale and babesia bigemina and the effect of the infections as characterised by anaemia was determined by the biweekly examination of newly born calves on four ranches located in an endemic area of anaplasmosis and babesiosis on the north coast of colombia. all of the calves examined became infected with a. marginale at 4-24 weeks of age and with b. bigemina at 2-34 weeks of age. the mean age at first infection with both hae ...1977562010
experiments on the babesia bigemina carrier state in east african buffalo and eland.three captive east african buffalo (syncerus caffer) were injected with 5 x 109 bovine erythrocytes with babesia bigemina pathogenic for cattle. none of the buffalo showed signs of disease, but babesia were found in blood smears for four days indicating their multiplication. the carrier state of babesia bigemina was established in two buffalo for 28 and 147 days respectively by sub-inoculation into splenectomized calves, while no parasites were demonstrated 28 days after injection in the third b ...1979543000
detection of babesia bigemina-infected carriers by polymerase chain reaction amplification.a spei-avai fragment (0.3 kbp) from pbbi16 (a pbr322 derivative containing a 6.3-kbp babesia bigemina dna insert) was subcloned into the pbluescript phagemid vector and was sequenced by the dideoxy-mediated chain termination method. two sets of primers were designed for the polymerase chain reaction (pcr) assay. primer set ia-ib was used to amplify a 278-bp dna fragment, and primer set ian-ibn was used to prepare a probe directed to a site within the pcr-amplified target dna. digoxigenin-dutp wa ...19921400956
the effect of neutrophils, tumor necrosis factor, and granulocyte macrophage/colony stimulating factor on babesia bovis and babesia bigemina in culture.bovine neutrophils, human recombinant tumor necrosis factor-alpha (tnf), and bovine recombinant granulocyte macrophage/colony stimulating factor (gm/csf) were added to microaerophilic cultures of babesia bovis and babesia bigemina to determine if those substances could inhibit growth. incorporation of [3h]hypoxanthine by the babesia spp. was utilized as an indirect measure of parasite growth. when neutrophils were added to cultures of b. bovis and b. bigemina, the highest percentage inhibition o ...19921413450
studies on theileriidae (sporozoa) in tanzania. viii. experiments with african buffalo (syncerus caffer).it has been found that african buffalo may remain infective carriers of theileria parva lawrencei for at least 5 years. this infection is now known to exist in buffalo in 3 sites in northern tanzania. it was shown that buffalo can be infected with haematoxenus veliferus and theileria mutans of cattle and retransmission of these parasites from buffalo to cattle was successful. the species of haematoxemus reported in wild buffalo in central and east africa is likely to be h. veliferus, while the p ...1977410128
identification of babesia bigemina in the tick boophilus decoloratus by the indirect fluorescent antibody technique.developing stages of babesia bigemina were detected in the giemsa-stained haemolymph smears of replete boophilus decoloratus females engorged on infected animals. replicate smears of these were prepared for staining by the indirect fluorescent antibody (ifa) technique. with specific antisera to b bigemina in dilutions up to 1/160 and rabbit antibovine globulin conjugated with fluorescein isothiocyanate (conjugate) the b bigemina stages were seen to fluoresce under the fluorescent microscope. whe ...1977333527
development and persistence of cowdria ruminantium specific antibodies following experimental infection of cattle, as detected by the indirect fluorescent antibody test.different breeds of cattle were experimentally infected with palm river, a zimbabwean isolate, or ball-3, a south african isolate of cowdria ruminantium, derived from tissue culture or tick or blood stabilates. c. ruminantium specific antibody responses were detected by an indirect fluorescent antibody test (ifat) using c. ruminantium-infected bovine aortic endothelial (bae) cell cultures as antigen. the first detection of antibodies to c. ruminantium generally coincided with the peak of the feb ...19921441219
comparisons of the complement-fixation and indirect fluorescent antibody reactions in the detection of bovine babesiasis.complement-fixation (cf) and indirect fluorescent antibody (ifa) antigens were prepared from babesia bigemina isolates obtained in texas. these serologic procedures were evaluated on 130 serum samples sequentially collected from 5 b bigemina-infected mature cattle, beginning on the day of exposure and continuing for 175 day thereafter. both tests were effective in detecting specific antibodies for the first 84 days of infection, with 57 of 60 (95%) serums tested being positive on the cf test and ...1977320922
recurring hemolytic anemia, babesiasis, and influenza a viruses in a yak at low altitude in nepal.episodes of hemolysis and leukocytosis which were associated with babesia bigemina followed each of 3 challenge exposures to influenza a viruses. it is possible that viral infection altered the immunologic host-parasite equilibrium. acute thrombocytopenia and rouleaux formation were also observed. death, attributed to liver flukes, occurred 168 days after the yak was transferred from high to low altitude. a 2nd yak died of foot-and-mouth disease, thus supporting the nepali belief that yaks will ...1975125056
evaluation of a colorimetric babesia bigemina-dna probe within an epidemiological survey.an epidemiological survey was conducted in southeast mexico, in an effort to establish the serological reactivity and carrier status to babesia bigemina of an indigenous cattle population. the prevalence was obtained through the indirect fluorescent antibody test (ifat), using an in vitro culture-derived b. bigemina antigen. a specific, digoxigenin-coupled, approximately 6 kb b. bigemina-dna probe (bbdp), was used to indicate the presence of the parasite. serum samples from 925 animals of all ag ...19921343694
studies on theileriidae (sporozoa) in tanzania. iv. a field trial on immunization against east coast fever (theileria parva infection of cattle).seven cattle, immunized by an infection and treatment method with 3 strains of theileria parva (muguga, kiambu 5 and serengeti transformed), and five controls were exposed to natural tick infestation in tanzania, at a site where 2 precontrols had previously contracted fatal east coast fever within 3 weeks. all controls became infected with fatal ecf within a month of exposure. one immunized animal survived, two died from a theileria mutans infection and one from a babesia bigemina infection. the ...1976982549
preliminary observations on the ultrastructure of suppossed sexual stages of babesia bigemina (piroplasmea). 1977919690
acute babesia bigemina infection: changes in coagulation and kallikrein parameters.plasma from splenectomized calves infected with b. bigemina were assayed for disturbances in the coagulation system. changes were observed in the wbct, ptt, pt, tt and rt as well as in fibrinogen, calcium and thrombocyte levels. these changes were most marked during days 6--7 when parasite numbers were greatest. massive intramuscular haemolysis coincided with these changes. the plasma kallikrein level fell progressively from days 6--11 and the level of activated kallikrein rose slightly. parasit ...1977919688
lyophilised bovine serum as a substitute for frozen serum in the cultivation of babesia bigemina and b bovis.lyophilised serum offers significant advantages over frozen serum when it comes to shipping such material over long distances. babesia bigemina and b bovis were cultured in medium supplemented by either frozen-thawed or lyophilised-rehydrated serum. there were no significant differences between the two types of medium in the growth of parasites and percentage of infected cells during subcultivation for 18 days.19921553430
a cloned dna probe for cowdria ruminantium hybridizes with eight heartwater strains and detects infected sheep.the dna probe pcs20, which was cloned from the dna of the crystal springs heartwater strain from zimbabwe, cross-reacted with dnas of heartwater strains from all endemic areas, including four heartwater strains from zimbabwe, two strains from south africa, one strain from nigeria, and the gardel strain from the caribbean island of guadeloupe. by nucleic acid hybridization, the pcs20 dna probe detected cowdria ruminantium dna in all dna preparations made from plasma samples from infected sheep be ...19921572987
acute babesia bigemina infection: changes in fibrinogen catabolism.plasma from cattle infected with babesia bigemina contained soluble fibrin in monomer and high molecular weight complex forms. fibrin(ogen) degradation products were not constantly detected and there appeared to be little or no evidence to suggest fibrinolysis or fibrin deposition. it is suggested that classical disseminated intravascular coagulation does not occur during b. bigemina infection.1977919687
a differential diagnostic criterion for babesia major and babesia bigemina vermicules from tick haemolymph.babesia major mature and immature vermicules in the haemolymph of haemaphysalis punctata were measured and found to be significantly larger than vermicules of babesia bigemina. mature b. major vermicules had a mean length of 15.53 micrometer and mature b. bigemina vermicules had a mean length of 11.79 micrometer. this difference provides a new criterion for the differentiation of the two species.1977906629
babesia bigemina in kenya: experimental transmission by boophilus decoloratus and the production of tick-derived stabilates.a babesia-free batch of laboratory reared boophilus decoloratus ticks was infected with a kenyan strain of babesia bigemina by feeding them on a steer infected by inoculation of a blood stabilate. the engorged female ticks showed developing stages of b. bigemina in their haemolymph and subsequently their progeny transmitted the parasite to a susceptible splenectomized steer. attempts were made to produce stabilates from pre-fed larvae and nymphs derived from infected batches of b. decoloratus. o ...1977876684
babesia rodhaini, babesia bovis, and babesia bigemina: analysis and sorting of red cells from infected mouse or calf blood by flow fluorimetry using 33258 hoechst. 197992419
immunization against anaplasmosis and babesiosis. part ii. evaluation of cryo-preserved vaccines using different doses and routes of inoculation.anaplasma marginale, babesia argentina and babesia bigemina infected blood used as vaccines for immunization trials in valle del cauca, were preserved with 4 molar dimethyl-sulfoxide (4m dmso) and stored in liquid nitrogen (-196 degrees c). the effectivity of the vaccines was determined in 87 healthy calves utilizing serial 10-fold dilutions. the effects of dose, inoculation routes, time and temperature were determined. the minimum infective dose for a. marginale was 10(-3) (2 x 10(6)) when 2 ml ...1978675843
babesia bovis, babesia bigemina, babesia canis, babesia microti and babesia rodhaini: comparison of ribosomal rna gene organization.the three ribosomal dna (rdna) units have been cloned from an australian isolate of babesia bigemina. the organization of the units is very similar to that reported for a mexican isolate of b. bigemina. in babesia canis four rdna units have been identified. both babesia rodhaini and babesia microti contain two different rdna units. a small number of different rdna units appears to be a common feature of this group of protozoa. restriction enzyme analysis of the rdna units form these species and ...19921428519
immunisation of cattle against theileriosis in nakuru district of kenya by infection and treatment and the introduction of unconventional tick control.one hundred and one cross european-boran cattle (50 cows and 51 calves), on a farm in nakuru district, kenya, were immunised against theileriosis using theileria parva lawrencei and theileria parva parva stocks from another district of kenya. the stabilates used were t.p.lawrencei (mara iii) used at 10(-1.7) dilution and t.p.parva (kilae) used at 10(-1.0) dilution. the stabilates were combined and inoculated simultaneously with a short-acting formulation of oxytetracycline hydrochloride given in ...19921496782
antibody response to babesia bigemina infection in calves measured by elisa and immunoblotting techniques.to measure the antibody response to babesia bigemina with an elisa test, three groups of cattle were experimentally infected with two isolates of the parasite. it was possible to demonstrate specific antibody binding directed against the parasite as early as the 7 days postinfection (pi). the highest level of antibody was obtained around day 1 to 23 and remained detectable for 260 days. challenge of the animals 260 days pi with a tick-induced b. bigemina infection depicted that homologous strain ...19921345116
indigenous and crossbred cattle--a comparison of resistance to ticks and implications for their strategic control in zimbabwe.a comparison of the tick resistance of indigenous mashona and crossbred afrikander x sussex oxen following natural tick infestation indicated that significantly more african blue ticks boophilus decoloratus were found on the crossbred than the indigenous cattle (p < 0.05). the two groups of cattle were exposed to babesia bigemina and theileria taurotragi as indicated by high antibody titres on the indirect fluorescent antibody test, but no antibodies could be demonstrated to anaplasma marginale ...19921305338
studies on transmission of babesia bigemina. 19751211980
immunization against anaplasmosis and babesiosis: part i. evaluation of immunization using minimum infective doses under laboratory conditions.a method of immunization against anaplasmosis and babesiosis using minimum infective doses was developed under laboratory conditions. stabilates of anaplasma marginale stored at -60 degrees c were found infective when diluted 10-fold to 10(-3). stabilates of babesia argentina and babesia bigemina stored under the same conditions were infective when diluted 10-fold to 10(-1). intact calves inoculated with the above dilutions of stabilates developed moderate parasitemias and recovered from infecti ...19761006801
development of an in vitro microtest to assess drug susceptibility of babesia bovis and babesia bigemina.continuous cultivation of the bovine hemoparasites babesia bovis and babesia bigemina was developed as an in vitro microtest to assess parasite susceptibility to babesicidal compounds. reproducibility of parasite multiplication rates was independent of culture size, making it possible to use a microscale of 100 microliters for each test sample. inhibitory concentrations (ic50s) of a commonly used babesicide, quinuronium sulfate, evaluated by this in vitro method were found to be 5 x 10(-8) g/ml ...19911779305
rediscovery of koch's "strahlenörper" of babesia bigemina. 1976997728
dna probes for the detection of babesia caballi.a genomic library of babesia caballi dna was constructed in the plasmid vector puc13. the specificity of the clones for b. caballi was established by the lack of hybridization to babesia equi, babesia bovis, babesia bigemina and equine dna. two probes, pbc11 and pbc191, were isolated that could detect 0.25 ng and 0.125 ng of b. caballi dna, corresponding to a parasitaemia of 0.12% and 0.06% respectively. pbc191 could detect b. caballi parasites in the blood of an experimentally infected horse as ...19911866181
ribosomal dna sequence comparison of babesia and theileria.previous studies on the taxonomy of babesia spp. (phylum apicomplexa) using morphological and life cycle characteristics have resulted in their classification into 3 subgenera, with the genus theileria being most closely related to them. using a strategy based on the direct sequence analysis of products derived by asymmetric pcr to determine the nucleotide sequences, we have tested the validity of this classification by sequencing the small subunit ribosomal rna genes amplified from 2 babesia sp ...19921518535
cloning and characterisation of members of a family of babesia bigemina antigen genes containing repeated sequences.bovine polyclonal antisera to babesia bigemina antigens separated by phenyl-sepharose chromatography were used to screen a b. bigemina lambda gt11 cdna expression library. eleven b. bigemina-specific cdna clones were studied in detail. dna sequencing of 2 representative clones identified open reading frames encoding polypeptides representing the carboxy-termini of 2 different proteins. both polypeptides contained a related central motif of tandem repeats flanked by a highly conserved carboxy-ter ...19921435874
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
epidemiology and control of bovine babesiosis in south africa.babesiosis is the cause of serious economic losses in south africa and involves most areas with an annual rainfall of more than 400 mm. both babesia bigemina and babesia bovis are present and both are considered to be important. the vectors, distribution and factors influencing enzootic stability of both species are discussed. except in some areas only marginally suitable for ticks, and where tick control alone may be adequate, control by immunisation is recommended. short term prevention can be ...1979576018
immunization of cattle against theileria parva bovis and their exposure to natural challenge.theileria parva bovis isolates were tested for their immunizing capacity under natural field challenge on willsbridge farm in the highveld of zimbabwe. fifteen susceptible sussex yearlings were immunized with the boleni stock and 15 with a mixture of three isolates from the farm, using tick-derived sporozoite stabilates. no chemoprophylaxis was used. a dose of 0.1 ml of stabilate appeared to be safe in preliminary laboratory experiments, but the reactions were severe in the sussex cattle and one ...19902125158
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
[ticks and hemoparasitic diseases in cattle in senegal. iv. the southern sudan area].the authors report on the results of an investigation on ticks and hemoparasitoses of cattle, sheep and goats in the south sudanian area of senegal. systematic routine dipping against ticks of cattle, 40 sheep and 40 goats was set during 15 months, with a view to determine the population dynamics together with an acurate localization of the different species concerned. the following parasites were collected from these ruminants: amblyomma variegatum, boophilus geigyi, hyalomma truncatum, h. m. r ...19902218038
rrna-based method for sensitive detection of babesia bigemina in bovine blood.three synthetic oligonucleotide probes complementary to unique regions of babesia bigemina small-subunit rrna were developed for detecting the parasite in bovine blood. these probes specifically detected a parasitemia of 2 x 10(-5)% by autoradiography in less than 24 h by using a 200-microliters sample of bovine blood. these probes did not bind to total rna or genomic dna isolated from another closely related species, babesia bovis, or to bovine leukocyte rna. this method detected b. bigemina in ...19921629339
bovine helper t cell clones recognize five distinct epitopes on babesia bovis merozoite antigens.helper t cell clones from two babesia bovis-immune cattle were characterized for use in identification of potentially protective immunogens of b. bovis merozoites. proliferation assays with 11 cd4+ clones revealed a differential pattern of response to soluble cytosolic antigen, membrane-enriched antigen, detergent extracts of the membrane-enriched antigen, soluble culture supernatant exoantigen, and different geographical isolates of b. bovis as well as babesia bigemina parasites. when the data ...19921383149
dna probes distinguish geographical isolates and identify a novel dna molecule of babesia bovis.a genomic dna library of babesia bovis was screened to identify dna probe candidates for direct detection of the parasite. two sequences, bo6 and bo25, had the highest sensitivity and further analysis revealed unique characteristics of each of these. neither sequence hybridized detectably to bovine dna. bo6 detected 100 pg of both a mexican and an australian isolate of b. bovis, but bo6 also detected 1.0 ng of babesia bigemina dna under identical conditions. a unique characteristic of bo6 is tha ...19902254817
serological and immunological studies with a hexane extract of babesia bovis-infected erythrocytes.antigenic and immunogenic activities of a hexane extract from babesia bovis-infected erythrocytes were investigated. positive elisa and ifat reactions were obtained with bovine antisera to b. bovis and b. bigemina produced by natural infection and rabbit antisera to the hexane extract, respectively. in contrast, negative elisa reactions were obtained with anaplasma marginale antisera indicating that the antigen(s) is specific for the genus babesia. the ifat clearly demonstrated that the antigen ...19921383165
post-thawing viability of vaccines for bovine babesiosis and anaplasmosis cryopreserved with glycerol.live frozen vaccines containing babesia bovis, babesia bigemina or anaplasma centrale were prepared using glycerol as cryoprotectant and stored in liquid nitrogen. the viability of the vaccines was tested inoculating calves 1 h (n = 12), 2 h (n = 12), 12 h (n = 6) and 24 h (n = 6) after thawing. babesia bovis and a. centrale were detected in thin and/or thick blood smears in all vaccinated calves; however, 1 of 12 calves inoculated 1 h after thawing and 3 of 6 calves inoculated 24 h after thawin ...19902267730
screening of a babesia bigemina cdna library with monoclonal antibodies directed to surface antigens.a babesia bigemina cdna library prepared in lambda zap bacteriophage vector was immunoscreened to detect clones expressing surface-exposed epitopes of b. bigemina. a nonradioactive indirect plaque-lift immunoassay was used to detect the positive clones. the primary antibody consisted of a pooled sample of six monoclonal antibodies (mab) specific for b. bigemina that recognizes various parasite surface antigens of different molecular mass. screening of approximately 300,000 plaque-forming units f ...19921378255
tick-borne diseases of cattle in paraguay. i. seroepidemiological studies on anaplasmosis and babesiosis.a serological survey was carried out in paraguay to determine the prevalence of antibodies to anaplasma marginale, babesia bigemina and babesia bovis. the results suggest that the parasites are widely distributed throughout the country with prevalence rates of 92% for a. marginale, 79% for b. bigemina and 71% for b. bovis. epidemiological studies on calves demonstrated that initial infection with the three blood parasites occurs in most animals within the first nine months of life. it is likely ...19902321261
characterization of a repetitive dna probe for babesia bigemina.a plasmid (p16) containing a babesia bigemina dna insert was selected and labeled with 32p. this probe was evaluated for specificity and sensitivity by dot blot hybridization. the probe was specific and hybridized with only babesia bigemina dna, and not dna from babesia bovis, bovine leukocyte, trypanosoma brucei or anaplasma marginale. the dna probe detected as little as 10 pg of babesia bigemina dna. the probe hybridized with babesia bigemina isolates from mexico, the caribbean region and keny ...19902382379
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
seroepidemiological studies of bovine babesiosis on pemba island, tanzania.serological evidence of infection with babesia bovis and babesia bigemina at a number of sites in pemba was obtained using an enzyme-linked immunosorbent assay (elisa) capable of detecting the appropriate parasite-specific antibody. overall, 96% of animals were found to be positive for b. bovis, 88% were positive for b. bigemina and 88% were positive for both babesia species. antibody to b. bovis and b. bigemina was detected early in life in a number of calves born on pemba, and was considered t ...19901702568
identification of babesia bigemina and babesia bovis merozoite proteins with isolate- and species-common epitopes recognized by antibodies in bovine immune sera.immunoprecipitation of radiolabeled antigens with bovine antisera indicated that many babesia bigemina and babesia bovis merozoite proteins contain isolate-common epitopes, while at least 16 b. bigemina and 8 b. bovis proteins contain species-cross-reactive epitopes. one immunogenic, isolate-common, and species-specific candidate diagnostic protein from each species was identified.19882453470
characterization of the gene encoding a 60-kilodalton babesia bovis merozoite protein with conserved and surface exposed epitopes.a clone expressing a surface exposed, conserved epitope of a 60-kda merozoite polypeptide was identified in a cdna library constructed from a cloned mexico strain of babesia bovis. sequencing of the 1.9-kb insert (pbv60) revealed an open reading frame encoding a 65-kda polypeptide with a signal peptide and a tandemly repeated region. monoclonal antibody 23/56.156, which binds a surface exposed epitope on the native polypeptide, specifically immunoprecipitated [35s]methionine-labeled polypeptides ...19911712911
[ticks and hemoparasitoses of livestock in senegal. iii. the northern sudan area].the authors describe the results of a study on ticks and hemoparasitoses of cattle and small ruminants in the senegalese north-sudanian area. for 15 months, 40 bovine, 40 sheep and 40 goats received a routine dipping treatment, aimed at the determination of the tick population dynamics together with an accurate localization of the preferential sites for the different species. the following parasites were collected from the animals: hyalomma marginatum rufipes, h. truncatum, rhipicephalus lunulat ...19892485548
comparison of immunogenicity and virulence between babesia bigemina parasites from continuous culture and from a splenectomised calf. 19892619652
antibodies define multiple proteins with epitopes exposed on the surface of live babesia bigemina merozoites.babesia bigemina is one of several tick-borne hemoparasitic diseases of cattle that are inadequately controlled and cause substantial livestock production losses in tropical and subtropical climates. recovery from acute babesiosis is associated with development of protective immunity against subsequent challenge with both homologous and heterologous parasites. viable and infectious merozoites, the intraerythrocytic stage of b. bigemina responsible for clinical disease, were separated from contam ...19872435796
effect of different methods of maintenance on the pathogenicity and infectivity of babesia bigemina for the vector boophilus microplus.observations were made on the effects of five different methods of laboratory maintenance on the infectivity and virulence of babesia bigemina for the tick boophilus microplus. the original isolate was highly infective and virulent, causing premature death of engorged female ticks and reduced egg production. maintenance of the strain by syringe passage in unsplenectomised calves at six to 10 week intervals reduced both its infectivity and virulence for ticks. when slow passages were preceded by ...19892704879
repetitive dna probes for the detection of babesia equi.this report describes dna probes for the identification of babesia equi. a genomic library of b. equi was constructed in puc13. several clones were identified that hybridized strongly to b. equi dna. clone pbe33 hybridized specifically to b. equi dna and did not hybridize to horse dna nor to dna from babesia caballi, babesia bovis or babesia bigemina. two subclones of pbe33 (psb20 and peh21) containing b. equi repetitive sequences, could detect 0.49 ng and 0.97 ng b. equi dna, respectively.19892710167
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
sequence conservation among merozoite apical complex proteins of babesia bovis, babesia bigemina and other apicomplexa. 19911775174
sequence microheterogeneity of the three small subunit ribosomal rna genes of babesia bigemina: expression in erythrocyte culture.three distinct ribosomal rna (rrna) transcription units (rdna units), designated a, b and c, were identified in the intraerythrocytic protozoan parasite, babesia bigemina. these rdna units were cloned, and restriction maps were constructed showing the approximate location of the small and large rrna coding regions. the arrangement of the genes in the genome and copy number analysis suggests the presence of a single copy of each rdna unit per haploid genome. the complete nucleotide sequence of th ...19911840661
isolation, sequence and differential expression of the p58 gene family of babesia bigemina.four copies of the gene encoding the merozoite surface protein p58 from the protozoan hemoparasite babesia bigemina were amplified from genomic dna by polymerase chain reaction (pcr) techniques, molecularly cloned and subjected to dna sequence analysis. the amplified dna (bbg7, bbg9, bbg13, bbg14) could be placed into 2 classes with respect to its size and the length of the open reading frame (orf). with the exception of a single base substitution, the sequence of bbg13 is identical to the cdna ...19921501634
detection of babesia bovis carrier cattle by using polymerase chain reaction amplification of parasite dna.carrier cattle infected with babesia bovis are difficult to detect because of the low numbers of parasites that occur in peripheral blood. however, diagnosis of low-level infections with the parasite is important for evaluating the efficacies of vaccines and in transmission and epidemiological studies. we used the polymerase chain reaction (pcr) to amplify a portion of the apocytochrome b gene from the parasite and tested the ability of this method to detect carrier cattle. the target sequence i ...19921624551
enzyme-linked immunosorbent assay using solubilised antigen for detection of antibodies to anaplasma marginale.an enzyme-linked immunosorbent assay (elisa) was used to detect antibodies against anaplasma marginale. a marginale bodies were separated from parasitised erythrocytes by a modified nitrogen decompression method, sonicated, then solubilised with triton x-100 and used as the elisa antigen. in this elisa system the required amount of antigen protein was 16.2 ng for each well. in the course of experimental infections, of calves, significant antibody levels were detected by elisa and the complement ...19883238774
chromosomes of babesia bovis and babesia bigemina. 19921625699
monoclonal antibodies that distinguish trypanosoma congolense, t. vivax and t. brucei.monoclonal antibodies (moabs) were derived against in-vitro-propagated procyclic forms of trypanosoma congolense, t. vivax, t. brucei brucei and t.b. rhodesiense in order to identify antigens for use in immunodiagnosis of african trypanosomiasis. the antibodies have been tested against procyclic and bloodstream form trypanosomes of 13 t. congolense, six t. vivax six t.b. brucei, four t.b. rhodesiense, five t.b. gambiense and three t. simiae isolates from different geographical areas by indirect ...19873306569
in vitro adherence of erythrocytes infected with babesia bigemina and babesia rodhaini to thrombospondin.the adherence of erythrocytes infected with babesia bigemina and babesia rodhaini to thrombospondin (tsp) in vitro is demonstrated. blood with a range of parasitaemias was used and counts of cells which bound to tsp on plastic were significantly different from the controls with both babesia species. these studies indicated that tsp receptors are present on the surface of red blood cells infected with the two babesia species, although these parasites do not alter the membranes of infected erythro ...19902276864
extraction and preliminary use for diagnosis of soluble precipitating antigen from babesia bigemina.soluble antigen from bovine blood with a babesia bigemina parasitemia of 5-6% formed 4 precipitin lines in gel diffusion tests with antiserum from infected cattle. antigen was obtained from plasma and hemolysate by elution from deae cellulose columns and (nh4)2so4 precipitation as well as from washed parasite-erythrocyte stroma by sonication or freeze-thawing. about 5 ml of antigen suitable for diagnostic tests could be extracted from 200 ml of infected blood.1975807719
effect of temperature on transovarial transmission of babesia bigemina (smith and kilborne, 1893) in boophilus annulatus (say, 1821).the effect of the temperature on the transovarial passage of babesia bigemina has been studied in female boophilus annulatus during their oviposition. kinetes of babesia were present in eggs laid at the temperatures of 16, 20, 26, 28, 30 and 35 degrees c. the rate of infection was temperature dependent. it reached at least 50%, even at low temperatures. the average infection level at 26 and 30 degrees c was 270 kinetes per egg. however, between 20 and 35 degrees c the eggs laid during the first ...19883347984
identification of common surface antigens among babesia bigemina isolates by using monoclonal antibodies.a group of monoclonal antibodies (mab) was used to immunochemically characterize babesia bigemina surface components. two surface reactive mab by an ifat test were subsequently shown to bind to epitopes on the external surface of the parasite plasma membrane as evidenced by immunoelectron microscopy. parasite components with relative sizes of 68, 62, 60, 58, 56, 54, 51, 49, 48, 47, 43, 36 kda were identified with the group of mab in at least 6 geographically different b. bigemina isolates. the a ...19901693187
tick-borne diseases of cattle in paraguay. ii. immunisation against anaplasmosis and babesiosis.a total of 102 susceptible adult holstein friesian cattle imported into an area of paraguay where anaplasmosis and babesiosis are endemic were immunised by infection with anaplasma centrale and attenuated forms of babesia bigemina and babesia bovis obtained from uruguay. the results indicated that the attenuated forms of both babesia species protected cattle against heterologous field challenge whereas a. centrale did not invariably confer sufficient protection against a field challenge of a. ma ...19902196724
chronic splenitis as a possible complicating factor in calves inoculated with an attenuated redwater vaccine.in two consecutive years a total of 3810 calves were inoculated with the onderstepoort redwater live-blood vaccine, containing attenuated strains of babesia bigemina and babesia bovis. twenty calves died 8-13 days later due to b. bigemina-infection. necropsies were performed on 19 of these animals. in 11 calves the spleen was distinctly smaller than normal and its morphology was distorted, and showed changes of chronic splenitis. histological lesions in the spleens of 6 of the 11 calves are desc ...19873508205
prevalence of anaplasma marginale, babesia bigemina and b. bovis in nigerian cattle using serological methods.serum samples collected randomly from 500 cattle from the 10 northern states of nigeria were tested for antibodies against anaplasma marginale by indirect fluorescent antibody (ifa), card agglutination (ct) and capillary tube-agglutination (ca) tests. the serum samples were also examined for antibodies to babesia bigemina and b. bovis by the ifa test only. of the serum samples tested, 79.4% had antibodies against a. marginale by the ifa test, 40 and 25% in the ct and ca tests, respectively. the ...19863538640
vaccination of cattle with dextran sulphate-binding babesia bigemina antigens.dextran sulphate-bound babesia bigemina antigens were used in a preliminary vaccination study and were shown to elicit a protective immune response in cattle. a dextran sulphate-binding fraction of b. bigemina was further subfractionated on a phenyl sepharose column to give two fractions--one that strongly bound to the column (bound fraction) and one that did not (unbound fraction). two groups of cattle were each vaccinated with either the bound or the unbound fraction. these two groups of anima ...19921399246
identification of a theileria mutans-specific antigen for use in an antibody and antigen detection elisa.purified piroplasms of theileria mutans were used to immunize balb/c mice to generate monoclonal antibodies (moabs). the moabs recognized an antigen of a relative molecular mass of 32 kda in western blots. this antigen was also recognized by sera from cattle which had recovered naturally from experimental tick-transmission or infections induced by the blood stages of t. mutans. the moabs did not react, in indirect immunofluorescence or enzyme-linked immunosorbent assays (elisa), with the common ...19901698274
cell-mediated immune responses to babesia bovis merozoite antigens in cattle following infection with tick-derived or cultured parasites.peripheral blood mononuclear cells from cattle experimentally infected with babesia bovis were examined for parasite-specific cell-mediated immune responses. unfractionated merozoites and soluble and membrane fractions derived from merozoites were all antigenic for immune cattle, although the membrane fraction was the most stimulatory. cattle responded to different antigenic fractions in a differential manner, and only that animal immunized with autologous cultured parasites responded to parasit ...19912050406
effect of different methods of maintenance on the development and morphology of babesia bigemina in the gut of boophilus microplus.the development and morphology of babesia bigemina in the gut of boophilus microplus ticks were studied during laboratory maintenance of the babesia by four methods: tick transmission in unsplenectomised (intact) calves; tick transmission in splenectomised calves; syringe passage at intervals of five days or less in splenectomised calves; and syringe passage at intervals of six weeks or more in intact calves. the first method had no apparent effect on the development of b bigemina in ticks compa ...19863704330
chemoprophylactic activity of imidocarb, diminazene and oxytetracycline against babesia bovis and b. bigemina.splenectomized calves treated with imidocarb, diminazene, and oxytetracycline were exposed to babesia bigemina and b. bovis stabilates at various time intervals following treatment to evaluate prophylactic efficacy. diminazene showed no residual activity against a b. bigemina challenge given 54 days after treatment. oxytetracycline appeared responsible for an increased incubation time when given 2 days prior to b. bigemina exposure. imidocarb showed marked prophylactic efficacy against both b. b ...19863739203
the inability of a south african babesia bovis vaccine strain to infect boophilus microplus.a strain of babesia bovis that had been attenuated by rapid syringe passage through a series of 23 splenectomized calves was unable to infect its vector boophilus microplus. an attempt to transmit the attenuated australian babesia bigemina g strain with a south african strain of b. microplus was likewise unsuccessful. the epidemiological implication of these observations in terms of babesiosis control is discussed.19863763166
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