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bovine anaplasmosis and babesiosis in the lesser antilles: risk assessment of an unstable epidemiologic situation.a seroepidemiological survey on tick-borne diseases of ruminants was carried out on 11 islands of the lesser antilles from grenada to st martin. a total of 1,795 cattle were randomly sampled and sera tested for antibodies to anaplasmosis (anaplasma marginale) and babesiosis (babesia bovis and b bigemina) using a dot-elisa test. except for anaplasmosis, which was virtually absent from guadeloupe, the seroprevalence of the 3 tick-borne diseases ranged from 18 to 71%. the epidemiologic situation wa ...19948038806
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
taxonomic position of the rickettsiae: current knowledge.the term rickettsiae initially encompassed all intracellular bacteria. early rickettsial taxonomy was based on a comparison of a few phenotypic characteristics and recently, molecular studies brought new bases for rickettsial taxonomy. all rickettsial species studied so far belong to the alpha and gamma groups of the proteobacteria. ehrlichiae complex groups cowdria ruminantium, anaplasma marginale and wolbachia pipientis and the related parthenogenesis and cytoplasmic incompatibility bacteria, ...19948117465
molecular cloning, sequence analysis, and expression of the gene encoding the immunodominant 32-kilodalton protein of cowdria ruminantium.cowdria ruminatium, the causative agent of heartwater disease, expresses an immunodominant and conserved 32-kilodalton protein (map1; formerly called cr32), which is currently in use for serodiagnosis of the disease. the gene encoding this protein, designated map1, was detected, cloned, and characterized. the gene is conserved between four different stocks of c. ruminantium originating from senegal, sudan, south africa, and zimbabwe. homology searches revealed map1 to be homologous to the anapla ...19948132352
recombinant vaccinia virus expression of anaplasma marginale surface protein msp-1a: effect of promoters, leader sequences and gpi anchor sequence on antibody response.anaplasma marginale surface protein msp-1a was expressed by recombinant vaccinia viruses with different promoters and as hybrid proteins. transcription of msp1 alpha with p11 late promoter resulted in more msp-1a than with p7.5 early-late promoter; however, mice immunized with the recombinants had similar antibody titres. recombinants expressing hybrid msp-1a with either a murine leukaemia virus or a trypanosomal glycoprotein signal sequence did not enhance antibody responses and resulted in a d ...19948023555
an attempt to transmit anaplasma marginale by buffalo flies (haematobia irritans exigua). 19948048908
the immunoprotective anaplasma marginale major surface protein 2 is encoded by a polymorphic multigene family.an anaplasma marginale florida msp-2 gene was cloned and expressed in escherichia coli. pulsed-field gel electrophoresis and southern blot analysis revealed the presence of multiple msp-2 gene copies that were widely distributed throughout the chromosomes of all three strains examined. genomic polymorphism among copies was greatest in the 5' end of msp-2 but also occurred in 3' regions. the presence of gene-copy-specific epitopes was indicated by the reactivity of the cloned msp-2 copy with some ...19948063397
molecular and biological characterization of a newly isolated anaplasma marginale strain.anaplasma marginale, a rickettsial hemoparasite of cattle and other ruminants, results in significant economic losses worldwide. distinct strains of a. marginale have been identified based on differences in tick transmissibility, molecular size of surface proteins and dna restriction fragments, and reactivity to a panel of monoclonal antibodies. these different strains vary considerably in their virulence, antigenic composition, and ability to protect against heterologous challenge. in this pape ...19947858023
polymerase chain reaction-based diagnostic assay to detect cattle chronically infected with babesia bovis.from a b. bovis gene sequence coding for a 60 kda merozoite surface protein previously published, two sets of primers were designed for the polymerase chain reaction (pcr) assay. primer set bof/bor was used to prime taq polymerase dna amplification of a 350 bp fragment of the target b. bovis dna. primer set bofn/born was used to prepare a pcr-synthesized, digoxigenin-dutp-labeled probe (291 bp) which would hybridize to a sequence within the pcr-amplified parasite target dna. pcr amplification of ...19947938942
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
16s rrna gene sequence of neorickettsia helminthoeca and its phylogenetic alignment with members of the genus ehrlichia.neorickettsia helminthoeca (tribe ehrlichieae, family rickettsiaceae) is the agent of salmon poisoning disease, which affects members of the family canidae. this bacterium is unusual in that it is the only known obligately intracellular bacterium that is transmitted via a helminth vector. the nucleotide sequence of the n. helminthoeca 16s rrna gene was determined and compared with the sequences of intracellular bacteria belonging to the alpha subgroup of the proteobacteria. the n. helminthoeca s ...19957537055
detection of anaplasma ovis infection in goats by major surface protein 5 competitive inhibition enzyme-linked immunosorbent assay.a competitive inhibition enzyme-linked immunosorbent assay (elisa) based on a major surface protein 5 (msp5) b-cell epitope conserved among anaplasma species was used to detect goats infected with anaplasma ovis. we examined strains of a. ovis isolated from goats in kenya and demonstrated that msp5 and the target b-cell epitope, bound by monoclonal antibody anaf16c1, were conserved. sera from 149 goats in four regions of kenya and from 302 goats in six u.s. states were tested for the presence of ...19957538510
live vaccines against hemoparasitic diseases in livestock.live vaccines against hemoparasitic diseases in livestock are based on parasites derived from culture (theileria annulata), from blood of infected animals (babesia bovis, babesia bigemina, anaplasma centrale, (attenuated) anaplasma marginale and cowdria ruminantium), and from ticks (theileria parva). the t. annulata attenuated cultured schizont vaccine is safe for all varieties of cattle. blood derived vaccines are recommended mainly for young cattle, the age limit varying with the different vac ...19957597786
molecular basis for vaccine development against anaplasmosis and babesiosis.immunization of livestock against the erythroparasitic pathogens anaplasma marginale, babesia bigemina, and babesia bovis with safe and effective killed vaccines is not yet feasible on a practical basis. however, the immune protection afforded by recovery from natural infection and premunition indicates that microbial epitopes capable of inducing immunity exist and that the bovine immune system can be primed appropriately. induction of protection by immunization with killed parasite fractions, e ...19957597787
vaccine development from a commercial point of view.the development of a commercial vaccine comprises distinct stages. initiation of a research project is triggered by demands from the market. if commercial and technical requirements are met, a feasibility study is carried out. research is started, and aimed at formulating the product profile (what the product looks like). the product profile is subject to requirements set by the market (e.g. whether the product will fit into existing vaccination schedules) and very often technical aspects affect ...19957597789
recent developments in the molecular biology of anaplasmosis.recent applications of dna analysis, cloning, sequencing and expression technology have resulted in significant advances in our understanding of the hemoparasite anaplasma marginale. analysis of 16s ribosomal rna has confirmed a phylogenetic position close to ehrlichia sp. and cowdria ruminantium. intact genomic dna of a. marginale digested with sfii separates into bands from 14 to 170 kbp on pulse-field gels, with a total genome size of 1200-1260 kbp and g + c content of 56 mol%. major surface ...19957597790
epidemiology of babesiosis and anaplasmosis in south and central america.babesiosis (babesia bovis and babesia bigemina) and anaplasmosis (anaplasma marginale) affect native cattle from uruguay and northern argentina to guatemala. the distribution of babesia follows the dissemination of the tick vector. seroepidemiological studies showed that enzootic instability exist in herds in several areas of the region. however, clinical cases occurred less frequently than expected. the babesial tick infection rate is related to the vector abundance which in turn is regulated b ...19957597777
targeting ticks for control of selected hemoparasitic diseases of cattle.development in and transmission of hemoparasites by tick vectors are phenomena closely synchronized with the tick feeding cycle. in all known life cycles, initial infection of tick tissues occurs in midgut epithelial cells and transmission is effected as ticks feed after parasites have developed and multiplied in salivary glands. many factors reviewed affect development and transmission of hemoparasites by ticks including age of ticks, artificial temperature, climate and/or season, tick stage or ...19957597779
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
conserved recombinant antigens of anaplasma marginale and babesia equi for serologic diagnosis.the competitive inhibition elisa (ci-elisa) format overcomes problems associated with antigen purity since the specificity of the ci-elisa depends solely on the monoclonal antibody (mab) used. therefore, the ci-elisa format is well suited for use with recombinant antigens. molecular clones expressing a conserved 19 kda protein of anaplasma marginale and a 34 kda protein of babesia equi were derived and characterized. the 19 kda a. marginale protein, conserved in all recognized anaplasma species, ...19957597796
effects of tick infestation and tick-borne disease infections (heartwater, anaplasmosis and babesiosis) on the lactation and weight gain of mashona cattle in south-eastern zimbabwe.the effects of ticks and tick-borne disease infections on the lactation and weight gain of mashona cattle were studied at mbizi quarantine station in the south-eastern lowveld of zimbabwe. twenty-nine mashona cows were allocated to 2 balanced groups and kept in separate paddocks at a stocking rate of one animal per 8 ha. one group received regular acaricide treatment to control bont (amblyomma hebraeum) and other ticks. the other group was left untreated. the cows were artificially inseminated. ...19957502343
recent developments in elucidating tick vector relationships for anaplasmosis and equine piroplasmosis.this brief review focuses first on several epidemiologically relevant aspects of anaplasmosis, including: (1) the role of male ticks as intrastadial, biological vectors of anaplasma through interhost transfer; (2) the application of molecular diagnostic assays in assessing tick vector competence and evaluating the role of chronically infected carrier cattle as sources of anaplasma marginale infection in vector ticks; (3) opportunities provided by a recently developed in vitro tick feeding system ...19957597797
an assessment of the role of white-tailed deer in the epizootiology of anaplasmosis in the southeastern united states.the role of white-tailed deer (odocoileus virginianus) in the epizootiology of anaplasmosis in the southeastern united states was examined through retrospective and prospective serosurveys and by experimental infection studies. no serum antibody reactive to anaplasma marginale was detected with an indirect fluorescent antibody (ifa) assay from any of 1,376 free-ranging deer sampled from 1968 through 1990 from 13 states and puerto rico. thirty-one additional deer from three bovine anaplasmosis en ...19958592360
susceptibility to different tick genera in gambian n'dama and gobra zebu cattle exposed to naturally occurring tick infestations.tick collection on one side of the body and whole tail was performed weekly over one year on 11 gambian n'dama (bos taurus) and 11 gobra zebu (bos indicus) cattle to assess breed susceptibility to naturally occurring ticks. enzyme-linked immunosorbant assay was also performed to assess the serological prevalence of anaplasma marginale antigen and babesia bigemina antibody. packed red cell volume was measured and liveweight gain was recorded. significantly higher numbers of amblyomma variegatum ( ...19957652946
theileria sergenti and t. buffeli: polymerase chain reaction-based marker system for differentiating the parasite species from infected cattle blood and infected tick salivary gland.benign theileria species in cattle. theileria sergenti and t. buffeli, are morphologically indistinguishable. the polymerase chain reaction (pcr) was used to amplify the genes encoding the 33- and 34-kda major piroplasm antigens (p33/34) of t. sergenti and t. buffeli from cattle blood infected with these parasites and tick salivary gland infected with t. sergenti. following amplification, the p33 gene from t. sergenti and the p34 gene from t. buffeli were clearly differentiated using the restric ...19958542983
detection of theileria annulata in blood samples of carrier cattle by pcr.we report the detection of theileria annulata, the causative agent of tropical theileriosis, by pcr in blood samples obtained from carrier cattle. the assay employs primers specific for the gene encoding the 30-kda major merozoite surface antigen of t. annulata. a 721-bp fragment was amplified from blood samples taken monthly from calves experimentally infected with one of four different stocks of t. annulata originating in either mauritania, portugal, spain, or turkey. at the end of the experim ...19958567902
detection of anaplasma marginale dna in bovine erythrocytes by slot-blot and in situ hybridization with a pcr-mediated digoxigenin-labeled dna probe.a 409-base pair (bp) dna fragment derived from the msp-1 beta gene of anaplasma marginale was amplified and simultaneously labeled with digoxigenin-11-dutp by a polymerase chain reaction (pcr) assay. the resulting digoxigenin-labeled 409-bp pcr product was used as a probe for slot-blot and in situ hybridization to detect a. marginale dna from experimentally infected bovine erythrocytes. the hybrid formation was detected with alkaline phosphatase-conjugated anti-digoxigenin antibody and substrate ...19958580166
association between polyneuritis and multiple sclerosis.we report two cases in which multiple sclerosis and inflammatory polyneuritis occurred separately, and suggest that this association supports the idea that the two conditions may have an aetiological link.1995228012
expression of major surface protein 2 antigenic variants during acute anaplasma marginale rickettsemia.antigenic variants of anaplasma marginale major surface protein 2 (msp-2), a target of protective immune responses, have been detected by use of copy-specific monoclonal antibodies reactive with some, but not all, organisms during acute rickettsemia. the presence of polymorphic msp-2 genes was confirmed by cloning and sequencing two gene copies, 11.2 and df5, each of which encodes a full-length msp-2 with a unique amino acid sequence. transcription of msp-2 genes during acute rickettsemia was an ...19968641789
preliminary studies on the effect of anaplasma marginale antibodies ingested by dermacentor andersoni ticks (acari:ixodidae) with their blood meal on infections in salivary glands.the effect of anaplasma marginale antibodies ingested with the tick blood meal was tested on infected male ticks that were allowed to feed on cattle immunized with the erythrocytic stage of a. marginale. the experiments were done in two trials. trial 1 was done using splenectomized calves (two calves per treated and control groups) while ticks in trial 2 were fed on intact yearling cattle (four cattle per treated and control groups). the cattle were immunized with purified outer membrane protein ...19968674360
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
comparative sensitivity of two tests for the diagnosis of multiple hemoparasite infection of cattle.the purpose of this study was to evaluate the efficacy of light microscopy (lm) examination of blood smears and a multiplex polymerase chain reaction (mpcr) assay, in terms of their ability to detect cattle experimentally infected with babesia bovis, babesia bigemina, and anaplasma marginale. blood samples were collected from 32 intact, 1-2 year old, holstein bulls, previous to and after simultaneous inoculation of culture-derived or field isolates of b. bovis- and b. bigemina-infected erythrocy ...19968784493
improving the specificity of indirect immunofluorescence for the serological diagnosis of bovine anaplasmosis.fluorescing inclusion appendages were detected consistently in preparations of anaplasma centrale and anaplasma marginale when they were used as antigen in indirect immunofluorescence serological tests for the diagnosis of anaplasmosis in cattle. the presence of the inclusion appendages made it possible to confirm the specificity of the immunofluorescent reaction and to determine end-points with accuracy.19968848303
antibody against an anaplasma marginale msp5 epitope common to tick and erythrocyte stages identifies persistently infected cattle.a protein epitope of major surface protein 5 (msp5), defined by monoclonal antibody (mab) anaf16c1, is conserved among anaplasma species (e. s. visser, t. c. mcguire, g. h. palmer, w. c. davis, v. shkap, e. pipano, and d. p. knowles, jr., infect. immun. 60:5139-5144, 1992) and is expressed in the salivary glands of infected ticks. a competitive inhibition elisa (celisa) for the detection of bovine anti-msp5 antibodies was developed by using purified recombinant msp5 fusion protein and mab anaf16 ...19968862589
effect on intraerythrocytic anaplasma marginale of soluble factors from infected calf blood mononuclear cells.blood mononuclear cells (lymphocytes and monocytes) were isolated from infected calves during in vivo control of acute anaplasmosis and cultured with anaplasma marginale organisms. supernatants from the cultures reduced the proportion of erythrocytes containing viable a. marginale in vitro, indicating that an antibody-independent mechanism of rickettsemia control might occur during acute anaplasmosis.19968890250
peripheral blood lymphocyte proliferative responses in cattle infected with or vaccinated against anaplasma marginale.an assay was developed for measurement of the peripheral blood lymphocyte proliferative response (pblpr) in cattle infected with or immunised against anaplasma marginale. pblpr was not evident in all cattle that had recovered from a. marginale infection. however, a. marginale-sensitised lymphocytes were detected in the spleens of all immune cattle tested in the absence of detectable pblpr. during the course of initial infection, cattle exhibited detectable pblpr for a period corresponding with a ...19968832738
susceptibility of elk (cervus elaphus) to experimental infection with anaplasma marginale and a. ovis.anaplasma ovis was experimentally transmitted from domestic sheep to elk (cervus elaphus) and back to splenectomized sheep. no rickettsemias were detected but serum from three of seven experimentally inoculated elk developed anaplasma spp.-reactive antibody as measured by indirect immunofluorescence (iif) or by the rapid card agglutination and complement fixation assays. three elk were experimentally infected with a. marginale. the rickettsiae were detected in blood of these elk and caused disea ...19968627938
ixodes (ixodes) scapularis (acari:ixodidae): redescription of all active stages, distribution, hosts, geographical variation, and medical and veterinary importance.the blacklegged tick, ixodes (ixodes) scapularis say, 1821, is redescribed, based on laboratory reared specimens originating in bulloch county, georgia. information on distribution, host associations, morphological variation, and medical/veterinary importance is also presented. a great deal of recent work has focused on this species because it is the principal vector of the agent of lyme disease (borrelia burgdorferi johnson, schmidt, hyde, steigerwaldt & brenner) in eastern north america. its d ...19968667375
strategies to interrupt the development of anaplasma marginale in its tick vector. the effect of bovine-derived antibodies.anaplasma marginale is a rickettsia transmitted by ticks that invades and multiplies in bovine erythrocytes causing the disease anaplasmosis. a complex developmental cycle occurs within ticks that begins in midgut cells, with subsequent infection in gut muscle cells. final development occurs in salivary glands from where the rickettsia is transmitted to the vertebrate host. at each site of development, a. marginale multiplies within membrane-bound inclusions. attempts to control anaplasmosis hav ...19968784497
enrofloxacin to control anaplasma marginale infections. 19968784531
evaluation of anaplasma marginale major surface protein 3 (msp3) as a diagnostic test antigen.an immunodominant surface protein, major surface protein 3 (msp3), has been proposed as an antigen suitable for use in the diagnosis of bovine anaplasmosis. we further characterized msp3 to examine its potential as a test antigen for the serological diagnosis of carrier cattle. the specificity of this antigen in detecting infected cattle as well as the conservation of msp3 between strains of anaplasma marginale was evaluated by using immunoblots of a. marginale proteins separated by one- and two ...19968788999
developmental studies of anaplasma marginale (rickettsiales:anaplasmataceae) in male dermacentor andersoni (acari:ixodidae) infected as adults by using nonradioactive in situ hybridization and microscopy.the development of anaplasma marginale theiler was studied in ticks using a nonradioactive in situ hybridization method developed in our laboratory. male rocky mountain wood ticks, dermacentor andersoni stiles, were infected intrastadially by allowing them to feed for 7 d on an infected calf (acquisition feeding). the ticks were then removed and held in a humidity chamber for 5 d before being fed on a 2nd susceptible call for 10 d (transmission feeding). two groups of 10 ticks were collected dai ...19968961639
establishment of the tick (acari:ixodidae)-borne cattle pathogen anaplasma marginale (rickettsiales:anaplasmataceae) in tick cell culture.anaplasma marginale is a tick-borne rickettsia that causes bovine anaplasmosis worldwide. despite its importance, a. marginale has thus far not been established in a continuous culture system. we have propagated a. marginale continuously for the 1st time in a tick cell line derived from the black-legged tick, ixodes scapularis say, using infected bovine blood as the inoculum. erythrocytic stages invaded the tick cells and multiplied in membrane-lined vacuoles to form colonies typical of those ob ...19968699463
prospects for subunit vaccines against tick-borne diseases.tick-borne parasites are a serious impediment to the improvement of live-stock production in the developing world. the major parasites affecting cattle include theileria parva, t. annulata, babesia bigemina, b. bovis, anaplasma marginale and cowdria ruminantium. the control of these infections is dependent on the use of acaricides to decrease transmission by the tick vectors, and immunization of susceptible animals with live vaccines. the use of acaricide is hampered by the development of resist ...19968979421
[clinical and hematological changes in calves infected with anaplasma marginale].clinical and hematological changes of six anaplasma marginale (isolated zulia) inoculated calves (experimental group) and four healthy calves (control group) were studied during twenty and eighty days before and after infection, respectively. the behavior of the four calves used as control group was stable and no significant changes in the parameters analyzed was observed. the experimental group developed the three typical phases of illness. during the prepatent phase, which lasted a mean of 21. ...19969334450
anaplasma marginale: detection of carrier cattle by pcr-elisa.a highly sensitive and specific polymerase chain reaction (pcr) based assay for the detection of the minute levels of anaplasma marginale present in the blood of long-term carrier cattle was developed. a simple lysis method was used to remove most of the haemoglobin from the blood to facilitate direct input of samples into the pcr reactions without prior purification of the dna. pcr product was detected by enzyme-linked immunosorbent assay (elisa) to simplify the processing of large numbers of s ...19968982791
development and validation of an indirect enzyme immunoassay for detection of antibody to anaplasma marginale in bovine sera.an indirect enzyme immunoassay (ielisa) for detection of bovine antibody activity to anaplasma marginale was developed. this assay used a crude antigen prepared from erythrocytes of infected calves, immobilized in a polystyrene matrix and a mouse monoclonal antibody to bovine igg1, conjugated with horseradish peroxidase. negative sera (n = 1842) were tested and the diagnostic specificity was 98.4 +/- 0.6% before retesting 29 positive samples. after retesting, eight samples remained positive and ...19969017861
anaplasma marginale: effect of challenge of cattle with varying doses of infected erythrocytes.three groups, each of 6 hereford cattle, were infected by the i.v. inoculation of 10(10), 10(8) or 10(6) anaplasma marginale-infected erythrocytes. the mean time taken to reach a 1% parasitaemia was 7.3, 13.9 and 19.9 days in the 10(10), 10(8)and 10(6) infection dose groups, respectively. the rates of increase in parasitaemias during the exponential phase of parasite multiplication were similar for the 3 groups (doubling time 0.9 days). the exponential increase of the parasitaemia in the 10(10) ...19969024896
artificial feeding of ixodid ticks.ixodid ticks are economically important as they cause direct damage to livestock and are vectors of several pathogens that cause diseases in humans and animals. some of the important tick-borne pathogens of livestock are theileria parva, t. annulata, babesia bigemina, b. bovis, anaplasma marginale and cowdria ruminantium. these pathogens are responsible for causing enormous losses in livestock. identification of factors that influence transmission and development of these pathogens in ticks will ...199615275192
different seasonal occurrence of anaplasmosis outbreaks in beef and diary cattle in an area of argentina free of boophilus microplus ticks.the seasonal occurrence of anaplasmosis (anaplasma marginale) outbreaks in dairy and beef cattle was analysed for a region of argentina (29 degrees to 31 degrees s and 58 degrees to 62 degrees w) that is free of boophilus microplus ticks, using data collected from december 1978 to november 1995. the outbreaks were confirmed by inspection of blood smears obtained from sick or dead cattle. a total of 94 outbreaks were confirmed by inspection of blood smears obtained from sick or dead cattle. a tot ...19979225428
carbohydrate moiety of plasmodium falciparum glycoproteins: the nature of the carbohydrate-peptide linkage in the msp-2 glycoprotein.metabolic labelling of plasmodium falciparum parasites with [3h]glcn, [3h]man, [3h]gal and [3h]ethanolamine, and subsequent purification by sds-page of the labelled material provided effective labelling of the msp-1, 195 kda, and msp-2, 42-53 kda, glycoproteins. reductive beta-elimination of the msp-2 released from the gel consisted of glycopeptides containing labelled sugars. processing of the eliminated components and identification of the sugar residues demonstrated the presence of n-acetylgl ...19979352084
seasonal prevalence of ticks and tick-transmitted haemoparasites in traditionally managed n'dama cattle with reference to strategic tick control in the gambia.a survey of tick spatial and seasonal distribution in traditional managed n'dama cattle over 1 year old was carried out in the gambia over 16 months. presence of anaplasma marginale and babesia spp. in the blood smears and their antibodies in the serum of same animals were also examined. tick species, in decreasing order of abundance, were: boophilus geigy, rhipicephalus senegalensis, b.decoloratus, hyalaomma truncatum, h.marginatum rufipes and amblyomma variegatum. all tick species peaked durin ...19979430113
variations in seroprevalence and host factors for bovine anaplasmosis in illinois.the modified card agglutination test (mcat) was used to detect antibodies to anaplasma marginale in 4994 samples collected from market cattle through the brucellosis eradication program in illinois. the mcat reactor rate in the sample was 6.4%. the statewide prevalence estimate increased to between 7.1% and 10.7% when corrected for sampling distribution and test sensitivity and specificity. while the sample reactor rate measures the proportion of infected cattle moving through the market system ...19979060138
anaplasma marginale major surface protein 3 is encoded by a polymorphic, multigene family.the immunodominant surface protein, msp3, is structurally and antigenically polymorphic among strains of anaplasma marginale. in this study we show that a polymorphic multigene family is at least partially responsible for the variation seen in msp3. the a. marginale msp3 gene msp3-12 was cloned and expressed in escherichia coli. with msp3-12 as a probe, multiple, partially homologous gene copies were identified in the genomes of three a. marginale strains. these copies were widely distributed th ...19978975906
prevalence of granulocytic ehrlichia infection among white-tailed deer in wisconsin.human granulocytic ehrlichiosis (hge) is caused by an agent that is nearly indistinguishable from the veterinary pathogens ehrlichia equi and ehrlichia phagocytophila. the deer tick, ixodes scapularis, is a vector of the hge agent, and the white-tailed deer is the primary host for adult ixodes ticks. we assessed the distribution of granulocytic ehrlichia infection among deer living within (wisconsin) and outside (western and southern iowa) the geographic range of l. scapularis. whole-blood sampl ...19979163463
increased resistance to anaplasma marginale infection in cattle chronically infected with theileria buffeli (syn. t. orientalis).calves chronically infected with the benign haemoprotozoan parasite theileria buffeli (syn. t. orientalis) and t. buffeli-free calves were experimentally infected with virulent anaplasma marginale. the daily mean maximum parasitaemia in the t. buffeli-carrier calves was lower and delayed relative to that of the theileria-free calves. anaemia was less marked in the theileria infected calves, although this difference was not statistically significant. the susceptibility of theileria-carrier and th ...19979195728
immunisation of smallholder dairy cattle against anaplasmosis and babesiosis in malawi.a field study was conducted in the southern region of malawi to evaluate the possible benefits of immunisation of improved dairy cattle against anaplasma marginale, babesia bigemina and babesia bovis. friesian crossbred heifers were immunised when they were being reared on government farms. they were then issued to smallholder farmers, together with unvaccinated controls, where many of them were exposed to heavy tick infestation. vaccination was shown to provide a significant degree of protectio ...19979203307
subunit vaccines for the control of tick-borne diseases: implications for the future.tick-borne parasites are a major constraint to the improvement of livestock productivity in the developing world. these parasites include theileria parva, t. annulata, babesia bigemina, b. bovis, anaplasma marginale and cowdria ruminantium. the impact of these diseases is currently limited by the use of acaricides to decrease transmission by the tick vectors and immunization of the host animals using live vaccines. the use of acaricide is hampered by the development of acaricide resistance and l ...19979530697
observations on the treatment of natural haemosporidia infections by total alkaloid of peganum harmala l. in cattle.eighty two cattle naturally infected with haemosporidians were treated with total alkaloid hydrochloride of peganum harmale l. (0.5 mg/kg/day). fifty eight cases with theileria sergenti showed a cure rate of 86%; thirteen cases with theileria annulata showed a cure rate of 85%; eight cattle infected with babesia bigemina showed a cure rate of 88% and three cases of anaplasma marginale were completely cured. the results suggested that the curative effect of total alkaloid of p. harmale was better ...19979512749
bovine anaplasmosis prevalence in northern veracruz state, mexico.in order to learn more about the presence of bovine anaplasmosis in northern veracruz state, méxico, paired blood and serum samples from 368 cattle were subjected to polymerase chain reaction (pcr) and complement-fixation test (cft). the overall prevalence of anaplasma marginale by pcr was 69.2% and seroprevalence by cft 54.6%. age-specific prevalence was calculated for each test. sixty-eight percent of animals from 0 to 3 months of age already were infected (pcr-positive), compared to only 42.4 ...19979443325
in vitro cultivation of anaplasma marginale in bovine erythrocytes co-cultured with endothelial cells.primary cultures of anaplasma marginale infected erythrocytes were used to determine conditions for in vitro cultivation of the rickettsia. the infected erythrocytes that were maintained by regular addition of glasgow's mem with fetal calf serum and uninfected erythrocytes showed a 1-5% increase in percent infected erythrocytes on the evaluation of giemsa stained smears. this increase in parasitemia resulted in up to 70% change in the number of infected erythrocytes. co-culture of the infected e ...19979477491
anaplasma marginale: effect of the treatment of cattle with an interferon gamma-neutralizing monoclonal antibody or the nitric oxide synthetase inhibitor aminoguanidine on the course of infection.cattle undergoing initial infection with the rickettsia anaplasma marginale were treated with either a monoclonal antibody (moab) with neutralizing activity for bovine interferon gamma (ifn-gamma) or aminoguanidine (ag), a specific inhibitor of the inducible form of nitric oxide synthetase (inos). plasma levels of moab and ag were measured over the time of administration. the course of a. marginale infection was not altered in the moab-treated cattle relative to untreated controls. in cattle tre ...19979347517
the prevalence of serum antibodies to tick-borne infections in cattle in smallholder dairy farms in murang'a district, kenya; a cross-sectional study.the most important tick-borne disease of cattle in eastern, central and southern africa is east coast fever (ecf) caused by theileria parva and transmitted by the tick rhipicephalus appendiculatus. other less-important tick-borne diseases in cattle are benign theileriosis caused by theileria mutans, babesiosis caused by babesia bigemina, anaplasmosis caused by anaplasma marginale and cowdriosis caused by cowdria ruminatum. in murang's district, central province of kenya, five agroecological zone ...19979234414
ultrastructure of anaplasma marginale with an inclusion appendage, isolated in minas gerais state, brazil.this is the first report on the occurrence and isolation of a strain of anaplasma marginale with an inclusion appendage in brazil. the inclusion appendage presented longitudinal electron-dense striations and did not originate directly from the body of the rickettsia but from an electron-dense complex located at the junction of the inclusion membrane and inclusion appendage. the inclusion appendage remained in the host cell after the anaplasma inclusion appeared to be leaving the red blood cell. ...19979211652
use of a nonradioactive dna probe for detection of anaplasma marginale infection in field cattle: comparison with complement fixation serology and microscopic examination.a sensitive anaplasma marginale-specific 409-base pair dna probe was developed in a previous study for detection of a. marginale infection in experimentally infected cattle with a test that employed slot-blot and in situ hybridization. to test the suitability of the probe to detect a. marginale in the blood of naturally infected carrier cattle, slot-blot hybridization was used to determine the infection rate of a. marginale in cattle from 3 geographic areas in oklahoma. for comparison, blood sam ...19979087923
serologic survey for infectious pathogens in free-ranging american bison.from november 1991 through march 1992, we evaluated 101 free-ranging american bison (bison bison) from yellowstone national park, wyoming (usa) for exposure to infectious organisms that commonly infect cattle. no titers were detected for bluetongue virus, bovine leukemia virus, or campylobacter fetus in these 101 bison. detectable antibodies occurred against anaplasma marginale (eight of 76, 11%), bovine respiratory syncytial virus (31 of 101, 31%), bovine viral diarrhea (31 of 101, 31%), bovine ...19979131564
effect of breed of cattle on innate resistance to infection with babesia bovis, b bigemina and anaplasma marginale.to assess the innate resistance of naive bos taurus, bos taurus cross bos indicus and bos indicus cattle to virulent babesia bovis, b bigemina and anaplasma marginale parasites.19979196820
western immunoblot analysis of haemobartonella muris and comparison of 16s rrna gene sequences of h. muris, h. felis, and eperythrozoon suis.infectious agents were isolated from the spleens of three wild mice (apodemus argenteus) by intraperitoneal inoculation of the spleen homogenate into laboratory mice. the laboratory mice developed clinical signs and splenomegaly, and three isolates were maintained by passage in mice. tetracyclines were effective in preventing infection of mice with these agents, but streptomycin and penicillin were ineffective. the agents did not grow in bacterial growth media or chicken embryos. in smears of bl ...19979157135
release of euchromatic segments by mg/ca-dependent autodigestion of chromatin. 1997174570
[ulcerative colitis or regional colitis]. 1998108580
[blood transfusion - practice at komagome municipal hospital. 1. specificity and adverse effects of blood transfusion (1)]. 1998105182
[comparison of 24 hours ambulatory electrocardiography and endocavitary recording in the diagnosis of heart rate disorders].ninety symptomatic patients aged between 16 and 90 years were investigated by ambulatory continuous 24 hour electrocardiography. 75 of these patients underwent endocavitary exploration of atrioventricular conduction and sinus node function within 48 hour of ambulatory electrocardiography. symptoms occurred during the recording in 30% patients, enabling the mechanism of the malaise to be determined. every time that abnormalities in the zone surrounding the tawara node were demonstrated by endocav ...1998106788
[prolonged parenteral feeding in surgery of the aorta with acute renal insufficiency]. 1998121370
prolactin secreting tumors. endocrine status before and after surgery in 33 women. 1998109458
genetic control of chromosome breakage and rejoining in drosophila melanogaster: spontaneous chromosome aberrations in x-linked mutants defective in dna metabolism.eight x-linked recombination-defective meiotic mutants (representing five loci) and 12 x-linked mutagen-sensitive mutants (representing seven loci) of drosophila melanogaster have been examined cytologically in neuroblast metaphases for their effects on the frequencies and types of spontaneous chromosome aberrations. twelve mutants, representing five loci, significantly increase the frequency of chromosomal aberrations. the mutants at these five loci, however, differ markedly both in the types o ...1998108678
synthesis of 4-(n-hydroxy-n-methylamino)quinoline 1-oxide and its carcinogenic activity on mice.4-(n-hydroxy-n-methylamino)quinoline 1-oxide (n-me-4-haqo), the structure of which consists of a quinoline 1-oxide moiety involved in carcinongenic 4-nitroquinoline 1-oxide and an n-hydroxy-n-methylamino group involved in n-hydroxy-n-monomethylaminoazobenzene, was sythesized and proved to be potently carcinogenic in mice by its subcutaneous injection.1998108171
immunodominant major outer membrane proteins of ehrlichia chaffeensis are encoded by a polymorphic multigene family.several immunodominant major proteins ranging from 23 to 30 kda were identified in the outer membrane fractions of ehrlichia chaffeensis and ehrlichia canis. the n-terminal amino acid sequence of a 28-kda protein of e. chaffeensis (one of the major proteins) was determined. the gene (p28), almost full length, encoding the 28-kda protein was cloned by pcr with primers designed based on the n-terminal sequence of the e. chaffeensis 28-kda protein and the consensus sequence between the c termini of ...19989423849
detection of cattle naturally infected with anaplasma marginale in a region of endemicity by nested pcr and a competitive enzyme-linked immunosorbent assay using recombinant major surface protein 5.a competitive enzyme-linked immunosorbent assay using recombinant major surface protein 5 (rmsp5-celisa) of anaplasma marginale was validated in a naturally infected cattle herd in an area of eastern oregon where a. marginale is endemic. the true positive and negative a. marginale infection status of 235 randomly selected cattle was determined by using a nested pcr (npcr) coupled with msp5 sequence analysis and hybridization. judgment of the reliability of the npcr and hybridization for detectio ...19989508311
conformational dependence of anaplasma marginale major surface protein 5 surface-exposed b-cell epitopes.the anaplasma marginale outer membrane is composed of immunogenic major surface proteins (msps) linked both covalently and noncovalently in multimeric complexes (m. c. vidotto, t. c. mcguire, t. f. mcelwain, g. h. palmer, and d. p. knowles, infect. immun. 62:2940-2946). consequently, effective induction of antibody against surface-exposed msp epitopes has been postulated to require maintenance of msp secondary through quatenary structures. using msp5 as a model and the approach of epitope mappin ...19989596725
evaluation of an enzyme-linked immunosorbent assay using recombinant major surface protein 5 for serological diagnosis of bovine anaplasmosis in venezuela.an indirect enzyme-linked immunosorbent assay (elisa) was developed for the serological diagnosis of bovine anaplasmosis with purified recombinant major surface protein 5 (msp5) of anaplasma marginale produced in escherichia coli. serum antibody responses against msp5 were detected in calves experimentally infected with a. marginale as early as 21 days postinfection and reached maximum titers at 28 days postinfection. the msp5 elisa performed with serum samples taken from field cattle from diffe ...19989521155
the safety and efficacy of australian tick-borne disease vaccine strains in cattle in paraguay.glycerol preserved, frozen tick-borne disease vaccine strains developed in australia were imported into paraguay to test their safety in pregnant holando heifers and their efficacy against challenge from inoculated local field strains of babesia bigemina, b. bovis and anaplasma marginale in hereford x criolla heifers. the two babesia strains proved to be safe and the b. bovis k strain was very effective in providing immunity to a local field strain of b. bovis. the b. bigemina efficacy trial was ...19989653988
bovine babesiosis and anaplasmosis follow-up on cattle relocated in an endemic area for hemoparasitic diseases.a multiplex pcr/dna probe assay was used to monitor babesia bovis, b. bigemina and anaplasma marginale infection in cattle introduced to a boophilus microplus-infested area in veracruz, mexico. eight intact, 18-month-old, cross-bred beef cattle (four naive, group a; four babesia species--premunized, group b) were immediately exposed to ticks after arrival and were clinically monitored from day 6 to day 98 post-exposure (pe) to ticks. blood sample analysis for dna detection by the mpcr/dna probe ...19989668444
characterization of an immunogen of anaplasma marginale. 19989668501
seroprevalence of anaplasma marginale in cattle in parana state, brazil, by msp-5 competitive elisa. 19989668503
prospective study for the detection of anaplasma marginale theiler, 1911 (rickettsiales: anaplasmataceae) in costa rica.a prospective study was conducted to assess the dynamics of the infection and host response to anaplasma marginale in one closed herd in the dry tropical forest of costa rica. the study subjects were the dams and their calves born during 1 breeding season (1995-1996). all cows were sampled at 3 month intervals for antibody detection using a competitive elisa (celisa) and for antigen detection using pcr/nonradioactive probe assay. all 24 calves born during the study were individually identified a ...19989668469
the development of a semi-automated latex agglutination test for the detection of antibodies to anaplasma marginale using a cell culture-derived antigen.serologic diagnosis of anaplasmosis is currently done by the complement-fixation, elisa, and card agglutination tests. these tests have utilized a. marginale harvested from bovine erythrocytes as antigen which is often contaminated with erythrocyte stroma. we are currently testing a. marginale propagated in a ixodes scapularis cell line as antigen for serologic tests. in this study, we report the use of the cell culture-derived a. marginale as antigen for development of a rapid, semi-automated l ...19989668476
major antigenic proteins of the agent of human granulocytic ehrlichiosis are encoded by members of a multigene family.western blot analysis of proteins from a cell culture isolate (usg3) of the human granulocytic ehrlichiosis (hge) agent has identified a number of immunoreactive proteins, including major antigenic proteins of 43 and 45 kda. peptides derived from the 43- and 45-kda proteins were sequenced, and degenerate pcr primers based on these sequences were used to amplify dna from usg3. sequencing of a 550-bp pcr product revealed that it encodes a protein homologous to the msp-2 proteins of anaplasma margi ...19989673253
characterization of anaplasma isolates from eland (taurotragus oryx). pathogenicity in cattle and sheep and dna profiles analysis.two eland anaplasma isolates, anape1, from kenya, and anape2, from south africa were characterised. their characterization was based on their pathogenicity to intact and splenectomized cattle and sheep and also their dna profiles. their dna profiles were analysed and compared to anaplasma marginale, a. ovis and a. centrale after endonuclease restrictions and probing with anaplasma dna probes, ac5-12 and ac-1. the results of the pathogenicity trials showed anape1 to be similar to a. ovis and anap ...19989561699
cloning of the gene encoding the 44-kilodalton antigen of the agent of human granulocytic ehrlichiosis and characterization of the humoral response.antibodies in the sera of patients with human granulocytic ehrlichiosis (hge) commonly recognize a 44-kda antigen. we cloned the gene encoding the 44-kda protein of the agent of hge (aohge) by probing an aohge lambda zap ii genomic dna expression library with sera from aohge-infected mice. the gene, hge-44, is part of a multigene family, with sequence similarity to the anaplasma marginale msp-2 genes. rna-pcr studies confirmed that hge-44 is expressed by aohge cultured in hl-60 cells and by aohg ...19989632594
development of a non-radioactive dna probe and in situ hybridization for detection of anaplasma marginale in ticks and cattle.a non-radioactive dna probe was developed for detection of anaplasma marginale in ticks and cattle. the probe was labeled with digoxigenin 11-dutp by polymerase chain reaction. the probe was tested on bovine blood and was found to be a sensitive and specific detection method for a. marginale in cattle. the dna probe was then adapted for in situ hybridization (ish) of a. marginale in dermacentor andersoni and d. variabilis ticks infected either as nymphs or adults. one-half of each tick was studi ...19989668458
evaluation of anaplasma marginale from tick cell culture as an immunogen for cattle.anaplasma marginale has been propagated and continuously passaged in an ixodes scapularis cell line. anaplasma development was characterized and cultures with a high density of rickettsiae were harvested at a predictable rate. culture-derived a. marginale (cam) remained infective for cattle and was used effectively as antigen in diagnostic tests with the sensitivity to identify bovine carriers of a. marginale. this study presents results of an initial trial using the cam as an immunogen for catt ...19989668472
use of tick cell culture-derived anaplasma marginale antigen in a competitive elisa for serodiagnosis of anaplasmosis.anaplasma marginale was propagated in a continuous tick cell line and detergent-solubilized infected cells were used as antigen in a competitive elisa (c-elisa) for detection of anaplasma-specific antibody in bovine sera. positive control sera competed well (> or = 35% inhibition) with an a. marginale-specific monoclonal antibody for binding to this antigen, while negative sera failed to compete (< 35% inhibition). the c-elisa was compared to the standard complement-fixation test (cft) using 2,2 ...19989668475
observations on the use of anaplasma centrale for immunization of cattle against anaplasmosis in zimbabwe.a total of 93 bos taurus cattle was used in pen trials to compare vaccine stocks of anaplasma centrale from south africa and australia (which stock came from south africa in 1934) in protecting against three virulent field isolates from clinical anaplasma marginale infections. in addition, field observations were made on the use of a vaccine, prepared from the australian stock, in over 9553 cattle of mixed age and breeds on 16 co-operator farms and at one communal dip. the results of the pen tri ...19989741051
development of an enzyme-linked immunosorbent assay for detection of antibodies to babesia bigemina in cattle.monoclonal antibodies, directed against a 58-kda babesia bigemina merozoite antigen that reacted strongly with immune sera from experimentally and naturally infected cattle in western blots, were used to develop a competitive-inhibition enzyme-linked immunosorbent assay (elisa). as based on the testing of 70 antibody-positive sera from experimentally infected cattle and 166 antibody-negative sera collected in non-endemic areas of australia, the sensitivity and specificity of the elisa were 95.7% ...19989747938
the repertoire of anaplasma marginale antigens recognized by cd4(+) t-lymphocyte clones from protectively immunized cattle is diverse and includes major surface protein 2 (msp-2) and msp-3.major surface proteins of anaplasma marginale are vaccine candidates. we recently demonstrated that immunization of calves with outer membranes of the florida strain of a. marginale resulted in protective immunity that correlated with a memory cd4(+) t-lymphocyte response specific for major surface protein 1 (msp-1), msp-2, and msp-3 (w. c. brown, v. shkap, d. zhu, t. c. mcguire, w. tuo, t. f. mcelwain, and g. h. palmer, infect. immun. 66:5406-5413, 1998). as immunogens, these proteins have been ...19989784552
the absence of clinical disease in cattle in communal grazing areas where farmers are changing from an intensive dipping programme to one of endemic stability to tick-borne diseases.a two-year field study was conducted in four communal grazing areas in south africa. sera were collected from young cattle (6-18 months old) in these areas during the winters of 1991 to 1993. the sera were tested for antibodies to babesia bovis, babesia bigemina, anaplasma marginale and cowdria ruminantium. in two of the four areas, treatment with acaricide was erratic and dependent on the discretion of individual owners. in these areas the drought of 1992 had a major impact on tick burdens and ...19989809321
cloning and characterization of multigenes encoding the immunodominant 30-kilodalton major outer membrane proteins of ehrlichia canis and application of the recombinant protein for serodiagnosis.a 30-kda major outer membrane protein of ehrlichia canis, the agent of canine ehrlichiosis, is the major antigen recognized by both naturally and experimentally infected dog sera. the protein cross-reacts with a serum against a recombinant 28-kda protein (rp28), one of the outer membrane proteins of a gene (omp-1) family of ehrlichia chaffeensis. two dna fragments of e. canis were amplified by pcr with two primer pairs based on the sequences of e. chaffeensis omp-1 genes, cloned, and sequenced. ...19989705412
morphology and development of anaplasma marginale (rickettsiales: anaplasmataceae) in cultured ixodes scapularis (acari: ixodidae) cells.anaplasma marginale theiler, a tick-borne rickettsial pathogen of cattle, was recently propagated in a continuous tick cell line, ide8, derived from embryonic ixodes scapularis say. cell monolayers were infected briefly with a high multiplicity of infection to synchronize rickettsial development and allow for description of the invasion, development, and release of a. marginale from the cultured cells. sequential samples were collected, fixed, and processed for examination with light and electro ...19989775610
expression of anaplasma marginale major surface protein 2 variants during persistent cyclic rickettsemia.anaplasma marginale is an intraerythrocytic rickettsial pathogen of cattle in which infection persists for the life of the animal. persistent a. marginale infection is characterized by repetitive rickettsemic cycles which we hypothesize reflect emergence of a. marginale antigenic variants. in this study, we determined whether variants of major surface protein 2 (msp-2), a target of protective immunity encoded by a polymorphic multigene family, arise during persistent rickettsemia. by using a qua ...19989488414
epidemiology of tick-borne diseases of cattle in botshabelo and thaba nchu in the free state province.a seroepidemiological study was conducted on 151 cattle from the botshabelo and thaba nchu areas in the central free state province of south africa, two areas where small scale, peri-urban cattle farming is practised. an indirect fluorescent antibody test was used to test for babesia bigemina and b. bovis antibodies. to test for anaplasma marginale antibodies a competitive inhibition enzyme-linked immunosorbent assay method was used. there were no significant differences in serological test resu ...199810192841
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