| diversifying selection and host adaptation in two endosymbiont genomes. | the endosymbiont wolbachia pipientis infects a broad range of arthropod and filarial nematode hosts. these diverse associations form an attractive model for understanding host:symbiont coevolution. wolbachia's ubiquity and ability to dramatically alter host reproductive biology also form the foundation of research strategies aimed at controlling insect pests and vector-borne disease. the wolbachia strains that infect nematodes are phylogenetically distinct, strictly vertically transmitted, and r ... | 2007 | 17470297 |
| molecular detection of ehrlichia ruminantium infection in amblyomma variegatum ticks in the gambia. | in west africa, losses due to heartwater disease are not known because the incidence/prevalence has not been well studied or documented. to develop a diagnostic tool for molecular epidemiology, three pcr-based diagnostic assays, a nested pcs20 pcr, a nested map1 pcr and a nested reverse line blot (rlb) hybridization assay, were evaluated to determine their ability to detect infection in vector ticks, by applying them simultaneously to a. variegatum field ticks to detect ehrlichia ruminantium, th ... | 2007 | 17476576 |
| conservation of transmission phenotype of anaplasma marginale (rickettsiales: anaplasmataceae) strains among dermacentor and rhipicephalus ticks (acari: ixodidae). | before the eradication of boophilus ticks from the united states, rhipicephalus (boophilus) microplus (canestrini) and rhipicephalus (boophilus) annulatus (say) were important biological vectors of the cattle pathogen anaplasma marginale theiler. in the absence of boophilus ticks, a. marginale continues to be transmitted by dermacentor ticks. however, a few u.s. strains are not transmissible by dermacentor andersoni stiles, dermacentor variabilis (say), or both, raising the question of how these ... | 2007 | 17547235 |
| gene conversion is a convergent strategy for pathogen antigenic variation. | recent studies on three unrelated vector-borne pathogens, anaplasma marginale, borrelia hermsii and trypanosoma brucei, illustrate the central importance of gene conversion as a mechanism for antigenic variation, which results in subsequent evasion of the immune response and persistence in the reservoir host. the combination of genome sequence data and in vivo studies tracking variant emergence not only provides insight into the genetic mechanisms for variant generation and hierarchy in variant ... | 2007 | 17662656 |
| comparison of the complement fixation test and competitive elisa for serodiagnosis of anaplasma marginale infection in experimentally infected steers. | to compare sensitivity of a complement fixation (cf) test and competitive elisa (celisa) for detection of anaplasma marginale in experimentally infected steers. | 2007 | 17669027 |
| anaplasmosis in cattle in italy. | bovine anaplasmosis caused by anaplasma marginale is a disease transmitted by ticks belonging to the ixodidae family. southern italy is considered an endemic zone but environmental and social factors are changing the epidemiology of the disease to expand to previously anaplasmosis-free regions. the available data of published reports of anaplasmosis in italy together with the data obtained by the national centre of reference for anaplasma, babesia, rickettsia and theileria (c.r.a.ba.r.t.), allow ... | 2007 | 17682850 |
| targeting the tick/pathogen interface for developing new anaplasmosis vaccine strategies. | bovine anaplasmosis is a tick-borne hemolytic disease of cattle that occurs worldwide caused by the intraerythrocytic rickettsiae anaplasma marginale. control measures, including use of acaricides, administration of antibiotics and vaccines, have varied with geographic location. our research is focused on the tick-pathogen interface for development of new vaccine strategies with the goal of reducing anaplasmosis, tick infestations and the vectorial capacity of ticks. toward this approach, we hav ... | 2007 | 17682853 |
| maintenance of antibody to pathogen epitopes generated by segmental gene conversion is highly dynamic during long-term persistent infection. | multiple bacterial and protozoal pathogens utilize gene conversion to generate rapid intrahost antigenic variation. both large- and small-genome pathogens expand the size of the variant pool via a combinatorial process in which oligonucleotide segments from distinct donor loci are recombined in various combinations into expression sites. although the potential combinatorial diversity generated by this segmental gene conversion mechanism is quite large, the functional variant pool depends on whet ... | 2007 | 17785476 |
| influence of dipping practices on the seroprevalence of babesiosis and anaplasmosis in the foot-and-mouth disease buffer zone adjoining the kruger national park in south africa. | a serological survey of bovine babesiosis and anaplasmosis was conducted in the foot-and-mouth disease buffer zone surrounding the kruger national park in south africa between 2001 and 2003 to determine whether the withdrawal of government-subsidized dipping in certain regions had affected the seroprevalence of these tick-borne diseases. seroprevalence of anaplasma marginale and babesia bovis increased during the study period. this increase was greater in limpopo province where farmers had to su ... | 2007 | 17883196 |
| experimental transmission of bovine anaplasmosis (caused by anaplasma marginale) by means of dermacentor variabilis and d. andersoni (ixodidae) collected in western canada. | canadian cattle are free of bovine anaplasmosis, with the exception of 4 isolated incursions since 1968, which were eradicated. it is not known why the disease has not become established in regions of canada adjacent to the united states where it is endemic. to assess the vector competence of wild-caught ticks in cattle-rearing regions, dermacentor variabilis and d. andersoni were collected in western canada and fed on calves experimentally infected with anaplasma marginale (st. maries strain). ... | 2007 | 17955901 |
| functional genomic studies of tick cells in response to infection with the cattle pathogen, anaplasma marginale. | the coevolution of ticks and the pathogens that they transmit has ensured their mutual survival. in these studies, we used a functional genomics approach to characterize tick genes regulated in response to anaplasma marginale infection. differentially regulated genes/proteins were identified by suppression-subtractive hybridization and differential in-gel electrophoresis analyses of cultured ide8 tick cells infected with a. marginale. nine of 17 of these genes were confirmed by real-time rt-pcr ... | 2007 | 17964755 |
| experimental transmission of anaplasma marginale by male dermacentor reticulatus. | bovine anaplasmosis has been reported in several european countries, but the vector competency of tick species for anaplasma marginale from these localities has not been determined. because of the wide distributional range of dermacentor reticulatus within europe and the major role of dermacentor spp. as a vector of a. marginale in the united states, we tested the vector competency of d. reticulatus for a. marginale. | 2007 | 18053123 |
| [transcription of genes of membrane proteins of brazilians isolates of anaplasma marginale]. | this work shows the transcription profile of membrane protein genes in three brazilian isolates of anaplasma marginale (rio grande do norte, pernambuco-zona da mata, and pernambuco-sertão). rna was purified from cattle blood experimentally-infected with the three isolates of a. marginale. after reverse transcription, genes omp1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 12, 13, and 14; opag1-3; virb3, 9, and 10; am097, 197, 254, 854, and 956 were amplified by pcr, with specific primers. transcripts were dete ... | 2007 | 18078602 |
| [natural infection by hemoparasites in calves submitted to chemoprophylaxis at 30 days of age]. | the tick-borne disease (tbd) brings great damages to cattle breeding. the most important etiologic agents are babesia bigemina, b. bovis and anaplasma marginale, being the tick boophilus microplus the main vector. this work reports the occurrence of natural infection by hemoparasites of tbd in 36 calves with high ticks natural infestation submitted to chemoprophylaxis with 30 days year-old. the blood smears from animals of different ages were analized and were found b. bigemina (33.3%), b. bovis ... | 2007 | 18078605 |
| development of a lateral flow assay for rapid detection of bovine antibody to anaplasma marginale. | a rapid lateral flow assay for detection of bovine antibody to anaplasma marginale was developed. the assay used a recombinant peptide of major surface protein 5 as the antigen and a monoclonal antibody specific for bovine igg(1) conjugated with colloidal gold beads for detection. serum and anticoagulated blood samples were obtained from cattle in an area where anaplasmosis was endemic. the samples were selected based on positive identification of the organism in blood smears. the unclotted bloo ... | 2008 | 18080877 |
| physical linkage of naturally complexed bacterial outer membrane proteins enhances immunogenicity. | the outer membrane proteins (omps) of bacterial pathogens are essential for their growth and survival and especially for attachment and invasion of host cells. since the outer membrane is the interface between the bacterium and the host cell, outer membranes and individual omps are targeted for development of vaccines against many bacterial diseases. whole outer membrane fractions often protect against disease, and this protection cannot be fully reproduced by using individual omps. exactly how ... | 2008 | 18086812 |
| sequential analysis of anaplasma phagocytophilum msp2 transcription in murine and equine models of human granulocytic anaplasmosis. | anaplasma phagocytophilum causes human granulocytic anaplasmosis by inducing immunopathologic responses. its immunodominant msp2 protein is encoded by a family of >100 paralogs. msp2 (msp2) expression modulates in the absence of immune pressure, and prolonged in vitro passage modulates in vivo virulence. because programmed msp2 expression occurs in anaplasma marginale, we hypothesized a similar event in a. phagocytophilum in vivo, with specific msp2 expression triggering immunopathologic injury ... | 2008 | 18094110 |
| high-throughput identification of t-lymphocyte antigens from anaplasma marginale expressed using in vitro transcription and translation. | the ability to rapidly screen a complex pathogen proteome for proteins that elicit recall t-lymphocyte responses from immune individuals would accelerate vaccine development. an outer membrane fraction of the rickettsial pathogen anaplasma marginale induces protective immunity against infection and disease in cattle. we have used this immunization model to evaluate high-throughput screening of proteins expressed by in vitro transcription and translation (ivtt) for recognition by memory cd4(+) t- ... | 2008 | 18243240 |
| superinfection as a driver of genomic diversification in antigenically variant pathogens. | a new pathogen strain can penetrate an immune host population only if it can escape immunity generated against the original strain. this model is best understood with influenza viruses, in which genetic drift creates antigenically distinct strains that can spread through host populations despite the presence of immunity against previous strains. whether this selection model for new strains applies to complex pathogens responsible for endemic persistent infections, such as anaplasmosis, relapsing ... | 2008 | 18252822 |
| selenium status and antibodies to selected pathogens in white-tailed deer (odocoileus virginianus) in southern minnesota. | to determine exposure to a variety of infectious diseases potentially important for native ungulates, livestock, and humans, serum samples from 114 (94 adults, 20 fawns) female white-tailed deer (odocoileus virginianus) were collected during january 2000-03 from multiple locations in southeast (se) and southwest (sw) minnesota. antibody prevalence was determined for the following pathogens: mycobacterium avium subsp. paratuberculosis, leptospira interrogans (six serovars), anaplasma marginale, b ... | 2008 | 18263838 |
| validation of an anaplasma marginale celisa for use in the diagnosis of a. ovis infections in domestic sheep and anaplasma spp. in wild ungulates. | a commercially available (celisa) kit for diagnosing anaplasma marginale infection in cattle was validated for diagnosing a ovis infection in sheep using the bovine serum controls as supplied by the manufacturer (bcelisa) and sheep serum controls from pathogen-free sheep (ocelisa). true positives were identified using two previously established assays, a nested pcr (npcr) test and an indirect immunofluorescent assay (ifa). the bcelisa was also applied to sera from various species of wild ruminan ... | 2008 | 18272296 |
| comparison of the efficiency of biological transmission of anaplasma marginale (rickettsiales: anaplasmataceae) by dermacentor andersoni stiles (acari: ixodidae) with mechanical transmission by the horse fly, tabanus fuscicostatus hine (diptera: muscidae). | mechanical transmission ofanaplasma marginale by horse flies (tabanidae) is thought to be epidemiologically significant in some areas of the united states. we compared the relative efficiencies of mechanical transmission of anaplasma marginale by the horse fly, tabanus fuscicostatus hine, during acute infection (approximately 10(7) to approximately 10(9) infected erythrocytes [ie]/ml blood) with biological transmission by dermacentor andersoni stiles in the persistent phase of infection (approxi ... | 2008 | 18283950 |
| composition of the surface proteome of anaplasma marginale and its role in protective immunity induced by outer membrane immunization. | surface proteins of tick-borne, intracellular bacterial pathogens mediate functions essential for invasion and colonization. consequently, the surface proteome of these organisms is specifically relevant from two biological perspectives, induction of protective immunity in the mammalian host and understanding the transition from the mammalian host to the tick vector. in this study, the surface proteome of anaplasma marginale, a tick-transmitted bacterial pathogen, was targeted by using surface-s ... | 2008 | 18316389 |
| parasitic infections in dairy cattle around hanoi, northern vietnam. | in northern vietnam, dairy cattle are mainly managed in small-scale farms, where animals are kept confined and feeding occurs by cut and carry methods. in the present study the occurrence of parasitic infections was examined in five provinces around hanoi. a total of 201 farms were visited, and 334 stool and 239 blood samples were collected from calves younger than 3 months, animals between 3 and 24 months and adult cows. furthermore, 254 milk samples were collected from lactating animals. copro ... | 2008 | 18328629 |
| concomitant infection of cattle with the vaccine strain anaplasma marginale ss centrale and field strains of a. marginale. | bovine anaplasmosis, caused by anaplasma marginale, the intraerythrocytic rickettsia, is controlled by vaccination with live anaplasma marginale ss centrale (a. centrale), a subspecies of relatively low pathogenicity. we have experimentally demonstrated that an animal primarily infected with a. marginale, or with the related vaccine subspecies a. centrale can be infected with the heterologous subspecies, and carries both bacteria. the co-infection was detected in experimentally cross-infected ca ... | 2008 | 18387757 |
| igg and igg2 antibodies from cattle naturally infected with anaplasma marginale recognize the recombinant vaccine candidate antigens virb9, virb10, and elongation factor-tu. | anaplasma marginale is an important vector-borne rickettsia of ruminants in tropical and subtropical regions of the world. immunization with purified outer membranes of this organism induces protection against acute anaplasmosis. previous studies, with proteomic and genomic approach identified 21 proteins within the outer membrane immunogen in addition to previously characterized major surface protein1a-5 (msp1a-5). among the newly described proteins were virb9, virb10, and elongation factor-tu ... | 2008 | 18425271 |
| productivity and health effects of anaplasmosis and babesiosis on bos indicus cattle and their crosses, and the effects of differing intensity of tick control in australia. | tick fever is an important disease of cattle where rhipicephalus (boophilus) microplus acts as a vector for the three causal organisms babesia bovis, babesia bigemina and anaplasma marginale. bos indicus cattle and their crosses are more resistant to the clinical effects of infection with b. bovis and b. bigemina than are bos taurus cattle. resistance is not complete, however, and herds of b. indicus-cross cattle are still at risk of babesiosis in environments where exposure to b. bovis is light ... | 2008 | 18472219 |
| molecular identification of anaplasma marginale and rickettsial endosymbionts in blood-sucking flies (diptera: tabanidae, muscidae) and hard ticks (acari: ixodidae). | in an attempt to identify the main vector and possible transmission routes of anaplasma spp. in a region of hungary with high prevalence of ovine and bovine anaplasmosis, dna was extracted from 316 haematophagous arthropods (individually or in pools), including 4 species of ixodid ticks, 6 species of tabanid flies and hornflies. midichloria-like organisms were identified with pcr (amplifying a portion of the 16s rrna gene) and sequencing from dermacentor marginatus and ixodes ricinus. significan ... | 2008 | 18495345 |
| in situ detection of anaplasma spp. by dna target-primed rolling-circle amplification of a padlock probe and intracellular colocalization with immunofluorescently labeled host cell von willebrand factor. | endothelial cell culture and preliminary immunofluorescent staining of anaplasma-infected tissues suggest that endothelial cells may be an in vivo nidus of mammalian infection. to investigate endothelial cells and other potentially cryptic sites of anaplasma sp. infection in mammalian tissues, a sensitive and specific isothermal in situ technique to detect localized anaplasma gene sequences by using rolling-circle amplification of circularizable, linear, oligonucleotide probes (padlock probes) w ... | 2008 | 18495855 |
| induced immune response of dna vaccine encoding an association msp1a, msp1b, and msp5 antigens of anaplasma marginale. | the outer membrane proteins of anaplasma marginale have been the focus of research to obtain an improved vaccine against bovine anaplasmosis. we evaluated the capacity of the recombinant plasmids pcdna-msp1alpha, pcdna-msp1beta, and pcdna-mp5 to express msp1a, msp1b, and msp5 proteins, and to determine the immunogenicity of balb/c mice immunized with these plasmids individually or in association. expression of proteins was confirmed in vero cells by ifa. the combination of recombinant plasmids s ... | 2008 | 18502005 |
| silencing expression of the defensin, varisin, in male dermacentor variabilis by rna interference results in reduced anaplasma marginale infections. | antimicrobial peptides, including defensins, are components of the innate immune system in ticks that have been shown to provide protection against both gram-negative and gram-positive bacteria. varisin, one of the defensins identified in dermacentor variabilis, was shown to be produced primarily in hemocytes but transcript levels were also expressed in midguts and other tick cells. in this research, we studied the role of varisin in the immunity of ticks to the gram-negative cattle pathogen, an ... | 2008 | 18523848 |
| studies on correlations among parasitaemia and some hemolytic indices in two tropical diseases (theileriosis and anaplasmosis) in fars province of iran. | this study was carried out in two observational clinical studies. study 1 comprised 50 adult crossbred cattle naturally infected by theileria annulata. infected animals were divided into 4 subgroups with different parasitaemia (<1%, 1-3%, 3-5% and >5%). study 2 comprised 20 adult crossbred cattle naturally infected by anaplasma marginale. infected animals were divided into 3 subgroups with different parasitaemia (<10%, 10-20% and 20-30%). in study 1, a significant negative correlation (p<0.001) ... | 2008 | 18551778 |
| cloning, sequencing and antigenic characterization of rvirb9 of anaplasma marginale isolated from paraná state, brazil. | anaplasma marginale, a tick-borne bacterium, causes bovine anaplasmosis responsible for significant economic losses in tropical and subtropical regions worldwide. various major outer membranes have been described, and virb9, a type iv secretion system protein, has been recently indicated as a candidate in vaccine development against anaplasmosis. the virb9 gene of an a. marginale strain isolated in paraná, brazil, was cloned by polymerase chain reaction and sequenced; its cloning into the petsum ... | 2008 | 18561379 |
| tick-borne transmission of two genetically distinct anaplasma marginale strains following superinfection of the mammalian reservoir host. | strain superinfection affects the dynamics of epidemiological spread of pathogens through a host population. superinfection has recently been shown to occur for two genetically distinct strains of the tick-borne pathogen anaplasma marginale that encode distinctly different surface protein variants. superinfected animals could serve as a reservoir for onward transmission of both strains if the tick vector is capable of acquiring and transmitting both strains. whether competition among strains dur ... | 2008 | 18573892 |
| clinical features associated with seroconversion to anaplasma marginale, babesia bigemina and theileria parva infections in african cattle under natural tick challenge. | a longitudinal study was conducted in southeast uganda for 14 months on 640 zebu cattle kept under natural tick challenge, with a view to identifying clinical features for prediction of seroconversion to anaplasma marginale, babesia bigemina and theileria parva infections. physical examination, condition scoring and tick counts were undertaken on all cattle every 4 weeks. in addition, 5300 sera were collected and analysed for antibodies against a. marginale, b. bigemina and t. parva infections u ... | 2008 | 18579313 |
| anaplasma marginale major surface protein 1a directs cell surface display of tick bm95 immunogenic peptides on escherichia coli. | the surface display of heterologous proteins on live escherichia coli using anchoring motifs from outer membranes proteins has impacted on many areas of biochemistry, molecular biology and biotechnology. the anaplasma marginale major surface protein 1a (msp1a) contains n-terminal surface-exposed repeated peptides (28-289 amino acids) that are involved in pathogen interaction with host cell receptors and is surface-displayed when the recombinant protein is expressed in e. coli. therefore, it was ... | 2008 | 18582976 |
| cloning, expression, and characterization of the msp1a and msp1b recombinant proteins from pr1 anaplasma marginale strain, brazil. | the anaplasma marginale is a bacterium that has obligate intraerythrocytic multiplication in cattle causing important economic loss. the a. marginale major surface protein 1 (msp1) complex, heterodimer composed of msp1a and msp1b, has been identified as adhesins for bovine erythrocytes. the objectives of this study were to sequences the msp1beta gene and produce and characterize recombinant msp1a and msp1b from a brazilian strain of a. marginale, pr1. the msp1alpha and msp1beta genes from the pr ... | 2009 | 18603273 |
| distribution and application of elisa for the seroprevalence of tick-borne diseases in central equatoria state, sudan. | this study was carried out to estimate the prevalence of theileria parva, theileria mutans, babesia bigemina and anaplasma marginale antibodies among naturally infected cattle in central equatoria state, southern sudan using indirect enzyme-linked immunosorbent assay (elisa). three locations (khor rumla, nyaing and gumbo) were selected and surveyed every 3 months during the period from january to december 2005. six cattle herds in the three locations were visited four times during the study peri ... | 2008 | 18666971 |
| pcr-based detection of blood parasites in cattle and adult rhipicephalus appendiculatus ticks. | to ascertain the infection rate for tick-borne pathogens in zambia, an epidemiological survey of theileria parva, babesia bigemina and anaplasma marginale in traditionally managed sanga cattle was conducted using pcr. of the 71 native zambian cattle, 28 (39.4%) were positive for t. parva, 16 (22.5%) for b. bigemina and 34 (47.9%) for a. marginale. the mixed infection rate in cattle was 8.5% (6/71), 16.9% (12/71), 7.0% (5/71) and 2.8% (2/71) for t. parva/b. bigemina, t. parva/a. marginale, b. big ... | 2009 | 18700182 |
| evaluation of sequential coinfection with anaplasma phagocytophilum and anaplasma marginale in cattle. | to determine whether sequelae of infection differed among single versus double infection with anaplasma phagocytophilum or anaplasma marginale, with and without tick salivary extract, in cattle. | 2008 | 18764690 |
| duplex real-time polymerase chain reaction for simultaneous detection and quantification of anaplasma marginale and anaplasma centrale. | anaplasma marginale and anaplasma centrale are rickettsial pathogens responsible for acute disease and mild infections, respectively, in cattle herds. a duplex real-time polymerase chain reaction (pcr) assay with probes labeled with different fluorophores was developed for simultaneous detection and quantification of a. marginale and a. centrale dna in bovine blood samples. the assay was able to detect as few as 10(1) and 10(2) dna copies for a. marginale and a. centrale, respectively, with opti ... | 2008 | 18776093 |
| [immune-humoral response of water buffalo (bubalus bubalis) against anaplasma marginale (theiler, 1910)]. | the aim of the present study was to analyze the humoral-immune response of water buffalo (bubalus bubalis) naturally infected against anaplasma marginale. for this work, colostrums/milk and blood samples were sequentially collected from buffalo cows prior and after partum for a period of 335 days and from buffalo calves from birth to 365 days after. the antibodies in the colostrums/milk and serum samples of these animals were determined using an elisa indirect method and the data were analyzed a ... | 2008 | 18823574 |
| frequency of antibodies to babesia bigemina, b. bovis, anaplasma marginale, trypanosoma vivax and borrelia burgdorferi in cattle from the northeastern region of the state of pará, brazil. | babesiosis, anaplasmosis, and trypanosomosis are relevant diseases, potentially causing morbidity in cattle, leading to economic losses. borreliosis is import as a potential zoonosis. the objective of this study was to determine, by indirect enzyme-linked immunosorbent assay (elisa), the frequency of seropositive cattle to babesia bigemina, b. bovis, anaplasma marginale, trypanosoma vivax and borrelia burgdorferi in cattle from the northeastern region of pará, brazil. sera samples from 246 femal ... | 2008 | 18823579 |
| outer membrane protein sequence variation in lambs experimentally infected with anaplasma phagocytophilum. | anaplasma phagocytophilum has long been known to cause tick-borne fever in ruminants and has been identified more recently as the causative agent of the emerging disease human granulocytic anaplasmosis. the related organism anaplasma marginale uses gene conversion of the expression site for two major outer membrane proteins (omps) to generate extensive sequence and antigenic variation in these omps. this is thought to present a continuously varying repertoire of epitopes to the mammalian host an ... | 2008 | 17967854 |
| [detection of antibodies against anaplasma sp. in small ruminants from the semi-arid region against pernambuco state, brazil]. | this paper reports the detection of antibodies against anaplasma sp. in goats and sheep from the semi-arid region from pernambuco state, brazil, using an enzyme-linked immunosorbent assay with recombinant msp5 of anaplasma marginale. sera from 243 goats and 68 sheep from ibimirim municipality were analyzed and frequencies of antibodies of 11.93% (29/243) and 16.17% (11/68) were found for goats and sheep, respectively. the epidemiological relevance of the findings was discussed. | 2008 | 18823582 |
| experimental transmission of field anaplasma marginale and the a. centrale vaccine strain by hyalomma excavatum, rhipicephalus sanguineus and rhipicephalus (boophilus) annulatus ticks. | the cattle rickettsia anaplasma marginale is distributed worldwide and is transmitted by about 20 tick species, but only rhipicephalus simus, a strictly african tick species, has been shown to transmit the vaccine strain of a. centrale. the aim of the present study was to examine transmission of field strains of a. marginale and of the vaccine strain of a. centrale by three tick species -hyalomma excavatum, rhipicephalus sanguineus and rhipicephalus (boophilus) annulatus - to susceptible calves. ... | 2009 | 18823724 |
| genetic diversity of anaplasma marginale strains from an outbreak of bovine anaplasmosis in an endemic area. | anaplasma marginale is a tick-borne pathogen of cattle that causes the disease bovine anaplasmosis worldwide. major surface proteins (msps) are involved in host-pathogen and tick-pathogen interactions and have been used as markers for the genetic characterization of a. marginale strains. a. marginale genotypes are highly variable in endemic areas worldwide. the genetic composition of a. marginale strains during anaplasmosis outbreaks has been characterized in one study only which reported a sing ... | 2008 | 18842342 |
| quantitative differences in salivary pathogen load during tick transmission underlie strain-specific variation in transmission efficiency of anaplasma marginale. | the relative fitness of arthropod-borne pathogens within the vector can be a major determinant of pathogen prevalence within the mammalian host population. strains of the tick-borne rickettsia anaplasma marginale differ markedly in transmission efficiency, with a consequent impact on pathogen strain structure. we have identified two a. marginale strains with significant differences in the transmission phenotype that is effected following infection of the salivary gland. we have proposed competin ... | 2009 | 18955472 |
| prevalence and genotypes of anaplasma species and habitat suitability for ticks in a mediterranean ecosystem. | anaplasma species are tick-transmitted pathogens that impact veterinary and human health. sicily is one of the locations where these pathogens are endemic. sicily represents a typical mediterranean ecosystem to study anaplasma infection and tick habitat suitability. the aims of this study were (i) to characterize by 16s rrna and species-specific msp4 gene pcr the prevalence and genotypes of a. marginale, a. phagocytophilum, and a. ovis in the most abundant host species in sicilian provinces and ... | 2008 | 18978093 |
| rapid deletion of antigen-specific cd4+ t cells following infection represents a strategy of immune evasion and persistence for anaplasma marginale. | acquired t cell immunity is central for protection against infection. however, the immunological consequences of exposing memory t cells to high ag loads during acute and persistent infection with systemic pathogens are poorly understood. we investigated this by using infection with anaplasma marginale, a ruminant pathogen that replicates to levels of 10(9) bacteria per ml of blood during acute infection and maintains mean bacteremia levels of 10(6) per ml during long-term persistent infection. ... | 2008 | 19017965 |
| seroprevalence of tick-borne diseases among cattle in the sudan. | this study was carried out to determine the prevalence of theileria annulata, theileria mutans, babesia bigemina, and anaplasma marginale antibodies among cattle in the sudan. a total of 600 serum samples were collected from indigenous (zebu) and crossbred cattle (zebu x friesian) of both sex and different age groups. indirect enzyme-linked immunosorbent assay was used to assess antibodies against tick-borne diseases in apparently healthy cattle. the overall prevalence rates of t. annulata, t. m ... | 2009 | 19030878 |
| detection of anaplasma antibodies in wildlife and domestic species in wildlife-livestock interface areas of kenya by major surface protein 5 competitive inhibition enzyme-linked immunosorbent assay. | the seroprevalence of anaplasma antibodies in wildlife (eland, blue wildebeest, kongoni, impala, thomson's gazelle, grant's gazelle, giraffe and plains zebra) and domestic animal (cattle, sheep and goat) populations was studied in wildlife/livestock interface areas of kenya. serum samples were analyzed by competitive inhibition enzyme-linked immunosorbent assay (ci-elisa), using a recombinant antigen (msp-5) from anaplasma marginale surface membrane. a monoclonal antibody, fc-16, was used as the ... | 2008 | 19040134 |
| ultrastructural and fluorochromatic changes of anaplasma marginale exposed to oxytetracycline, imidocarb and enrofloxacin in short-term erythrocyte cultures. | anaplasma marginale causes mild to severe hemoparasitic disease resulting in significant morbidity and mortality in cattle worldwide. in the absence of universally efficacious vaccines, antimicrobial therapy combined with biocontainment and biosecurity strategies are critical to control anaplasmosis. herein, we compared the effect of oxytetracycline, imidocarb and enrofloxacin on a. marginale isolates in short-term erythrocyte cultures. electron micrographs detailing antimicrobial-induced change ... | 2009 | 19054634 |
| characterization of 'candidatus neoehrlichia lotoris' (family anaplasmataceae) from raccoons (procyon lotor). | recently, a novel ehrlichial organism was isolated from a raccoon (procyon lotor) and the isolate (rac413) was infectious to two naïve raccoons but not laboratory mice, rats or rabbits. in this study, amplification and sequencing of four gene targets (16s rrna gene, groesl, glta and rpob) confirmed that the novel ehrlichial organism was a member of the family anaplasmataceae and was most closely related to, but distinct from, 'candidatus neoehrlichia mikurensis' tk4456(r) and is58. rac413 shared ... | 2008 | 19060060 |
| genetic diversity of major surface protein 1a of anaplasma marginale in beef cattle. | the present study was aimed to demonstrate genotypic diversity of anaplama marginale in infected beef herds grazing within anaplasmosis endemic regions. the genotypic diversity was identified among different herds, within each herd, and also within single animals. the israeli strains revealed unique characteristics of msp1a repeats and, in addition to the published repeats, six new tandem repeats designated is1-5, and is9 were identified. the superinfections of individual anaplama centrale vacci ... | 2009 | 19081688 |
| differential expression of the tick protective antigen subolesin in anaplasma marginale- and a. phagocytophilum-infected host cells. | subolesin was recently shown in vaccine and rna interference (rnai) studies to protect against tick infestations and to affect tick feeding, reproduction, and development as well as infection of host cells by anaplasma marginale and a. phagocytophilum. recent experiments provided evidence that infection of both tick and vertebrate host cells with these two pathogens modified gene expression. we therefore hypothesized that infection of host cells with a. marginale and a. phagocytophilum affects e ... | 2008 | 19120168 |
| characterization of anaplasma infections in sicily, italy. | this study aimed to characterize infection with anaplasma marginale, a. phagocytophilum, a. ovis, and a. platys in humans, animals, and ticks in sicily, italy, during 2003-2006. serologic (competitive elisa [celisa]) and indirect immunofluorescence antibody [ifa]; n= 1990) and dna (polymerase chain reaction [pcr]; n= 2788) tests were conducted on horse, donkey, cattle, sheep, goat, pig, dog, cat, roe deer, wild boar, human, and tick samples. the results reported herein suggested that in sicily c ... | 2008 | 19120181 |
| anaplasma marginale yucatan (mexico) strain. assessment of low virulence and potential use as a live vaccine. | anaplasma marginale yucatan strain was found to have low virulence in cattle. we studied the virulence of this isolate by experimental inoculation of 113 susceptible cattle at increasing doses, after which only one animal required treatment for clinical disease. subsequently, 104 cattle received a live vaccine of this strain by inoculation, which induced immunoprotection after heterologous challenged exposure with a different a. marginale isolate. in this study 14% of the immunized cattle requir ... | 2008 | 19120183 |
| first report of bovine anaplasmosis caused by anaplasma centrale in europe. | anaplasma centrale (rickettsiales: anaplasmataceae) is used as a live vaccine for cattle against the pathogenic anaplasma marginale in tropical and subtropical areas. herein we report a clinical case of bovine anaplasmosis associated with a. centrale infection in italy, together with the first molecular identification and phylogenetic analysis of this anaplasma species or subspecies in europe. | 2008 | 19120185 |
| flow cytometry to evaluate anaplasma marginale parasitemia using a fluorescent nucleic acid stain. | in this work we describe a flow cytometry-based method using syto16 (a dna intercalating agent) to quantify anaplasma marginale-infected erythrocytes in blood from bovine animals. the linearity and reproducibility of the results obtained with syto16 labeling followed by flow cytometry analysis make it a suitable approach for measurement of parasitemia in a. marginale infections. | 2008 | 19120186 |
| conservation in the face of diversity: multistrain analysis of an intracellular bacterium. | with the recent completion of numerous sequenced bacterial genomes, notable advances have been made in understanding the level of conservation between various species. however, relatively little is known about the genomic diversity among strains. we determined the complete genome sequence of the florida strain of anaplasma marginale, and near complete (>96%) sequences for an additional three strains, for comparative analysis with the previously fully sequenced st. maries strain genome. | 2009 | 19134224 |
| anaplasma marginale infection in a japanese black cow 13 years after eradication of rhipicephalus (boophilus) microplus in okinawa, japan. | in october 2007, a 15-year-old japanese black cow on ishigaki island, okinawa, japan, was diagnosed with anaplasma marginale infection based on clinical symptoms, blood examination, smear observation, 16s rrna and groel gene sequence analysis, and the result of a cf test. the cow was introduced into the farm from mainland japan as a calf in 1993, one year before the eradication of rhipicephalus (boophilus) microplus, the main vector of a. marginale in okinawa prefecture. it is possible that the ... | 2009 | 19135309 |
| propagation of a brazilian isolate of anaplasma marginale with appendage in a tick cell line (bme26) derived from rhipicephalus (boophilus) microplus. | anaplasma marginale is a tick-borne pathogen of cattle responsible for the disease anaplasmosis. data suggest that rhipicephalus (boophilus) microplus and r. annulatus may be the major tick vectors of a. marginale in tropical and subtropical regions of the world. in this work we demonstrated the first infection and propagation of a brazilian isolate of a. marginale (ufmg1) in the bme26 cell line derived originally from embryos of r. (boophilus) microplus. the establishment of a. marginale infect ... | 2009 | 19150177 |
| independence of anaplasma marginale strains with high and low transmission efficiencies in the tick vector following simultaneous acquisition by feeding on a superinfected mammalian reservoir host. | strain superinfection occurs when a second pathogen strain infects a host already carrying a primary strain. anaplasma marginale superinfection occurs when the second strain carries a variant repertoire different from that of the primary strain, and the epidemiologic consequences depend on the relative efficiencies of tick-borne transmission of the two strains. following strain superinfection in the reservoir host, we tested whether the presence of two a. marginale (sensu lato) strains that diff ... | 2009 | 19188360 |
| prevalence of anaplasma marginale in different tick species from ngorongoro crater, tanzania. | in 2001, ngorongoro crater was infested with high density of ticks on grassland, livestock and wildlife which was also associated with high mortality. adult ticks were collected, identified, processed for nucleic acids extraction and a molecular analysis was performed to determine the range of tick species harboring anaplasma marginale. the real-time pcr was used in the amplification of rickettsia dna in tick pools (n=527) from 11 identified tick species. six tick species were detected with a. m ... | 2009 | 19201099 |
| genetic diversity of anaplasma marginale in argentina. | bovine anaplasmosis caused by anaplasma marginale is a worldwide major constraint to cattle production. the a. marginale major surface protein 1 alpha (msp1alpha) gene contains a variable number of tandem repeats in the amino terminal region and has been used for the characterization of pathogen genetic diversity. this study reports the first characterization of a. marginale genetic diversity in argentina based on msp1alpha genotypes and its putative relationship with rhipicephalus (boophilus) m ... | 2009 | 19285808 |
| comparative moleculo-immunological analysis of swamp- and riverine-type water buffaloes responses. | this moleculo-epidemiological and immunological study through cytokine response assessment was done to know the dynamics of cytokines in the initiation, persistence and association to physiological changes of a particular pathogen in water buffaloes. this is important to understand the magnitude and behavior of disease progression. water buffalo blood samples gathered from different places in the philippines revealed a 9.4%, 27.6%, 10.3% and 4.4% prevalence of bovine viral diarrhea virus (bvdv), ... | 2009 | 19285880 |
| seroprevalence estimation and management factors associated with high herd seropositivity for anaplasma marginale in commercial dairy farms of puerto rico. | a cross-sectional study was conducted to determine individual cow seroprevalence of anaplasma marginale in adult lactating dairy cattle of puerto rico (pr) and to assess the associations of farm management factors on herd seroprevalence. antibody activity against a. marginale was determined using the msp-5 competitive enzyme-linked immunosorbent assay. serum samples were obtained from 2,414 adult lactating dairy cattle from 76 randomly selected commercial dairy farms. herd seroprevalence ranged ... | 2009 | 19337849 |
| ticks and tick-borne pathogens from wildlife in the free state province, south africa. | eight ixodid tick species, associated with 59 free-ranging mammals belonging to 10 species, were collected at five different localities in the free state province, south africa. four of the study areas were nature reserves (willem pretorius, sandveld, tussen-die-riviere, and soetdoring), and one site was a private farm located in senekal district. the collection was performed from march 2006 until june 2006. ticks (n=569) and tissues from animals (n=52) were analyzed by polymerase chain reaction ... | 2009 | 19395753 |
| first report of trypanosoma vivax infection in dairy cattle from costa rica. | an outbreak of haemoparasitoses occurred from october 2007 to july 2008 in cattle from the district of rio cuarto, province of alajuela, costa rica. fifty animals of various ages out of 450 brown swiss were affected. the animals presented fever, severe anemia, jaundice, abortion or premature birth, loss of appetite, decrease milk production and accentuated weight loss in a short period of time. haemoparasites were observed in the blood smears: anaplasma marginale was present in 17 animals (60.7% ... | 2009 | 19414224 |
| generation of antigenic variants via gene conversion: evidence for recombination fitness selection at the locus level in anaplasma marginale. | multiple bacterial and protozoal pathogens utilize gene conversion to generate antigenically variant surface proteins to evade immune clearance and establish persistent infection. both the donor alleles that encode the variants following recombination into an expression site and the donor loci themselves are under evolutionary selection: the alleles that encode variants that are sufficiently antigenically unique yet retain growth fitness and the loci that allow efficient recombination. we examin ... | 2009 | 19487473 |
| [seroprevalence of anaplasma marginale in cattle from center-south region of paraná state, brazil by a competitive elisa test with recombinant msp5-pr1 protein]. | anaplasma marginale prevalence was determined in 223 sera samples in 2-year old or older cattle, from the center-southern region of the paraná state, including ponta grossa, guarapuava and laranjeiras do sul municipalities. a survey of antibodies igg class against anaplasma marginale was performed through a competitive immune absorbent assay (celisa-pr1). from the 223 sera examined, 130 (58.74%) reacted to celisa-pr1 test, suggesting an region of enzootic instability, with a significant percenta ... | 2009 | 19500456 |
| validation and field assessment of a rapid lateral flow assay for detection of bovine antibody to anaplasma marginale. | the lateral flow assay (lfa) is a rapid diagnostic test which may be performed under most conditions and is especially useful for field applications. this type of assay was applied to the detection of antibody to bovine anaplasma marginale using sera from endemic areas and from areas which have been free from infection for more than 25 years. briefly, the test uses recombinant a. marginale major surface protein 5 peptide (msp5), immobilized on a cellulose acetate membrane. a serum sample is adde ... | 2009 | 19591044 |
| [cloning, expression, molecular characterization of the msp5 protein from pr1 strain of anaplasma marginale and its application in a competitive enzyme-linked immunosorbent test]. | a competitive enzyme-linked immunosorbent test using the pr1 recombinant major surface protein 5 (rmsp5-pr1-elisa) of anaplasma marginale was standardized and validated using sera from anaplasmosis free and endemic regions. the sequencing of the msp5 gene of pr1 isolate showed 98% of identity with the florida and saint maries isolates, 97% with brazil (pernambuco) and havana isolates; and 91% with a. centrale. the celisa-pr1 test was compared to ifi and celisa-usa. for the standardization and va ... | 2009 | 19602309 |
| silencing of genes involved in anaplasma marginale-tick interactions affects the pathogen developmental cycle in dermacentor variabilis. | the cattle pathogen, anaplasma marginale, undergoes a developmental cycle in ticks that begins in gut cells. transmission to cattle occurs from salivary glands during a second tick feeding. at each site of development two forms of a. marginale (reticulated and dense) occur within a parasitophorous vacuole in the host cell cytoplasm. however, the role of tick genes in pathogen development is unknown. four genes, found in previous studies to be differentially expressed in dermacentor variabilis ti ... | 2009 | 19607704 |
| anaplasma phagocytophilum and anaplasma marginale elicit different gene expression responses in cultured tick cells. | the genus anaplasma (rickettsiales: anaplasmataceae) includes obligate tick-transmitted intracellular organisms, anaplasma phagocytophilum and anaplasma marginale that multiply in both vertebrate and tick host cells. recently, we showed that a. marginale affects the expression of tick genes that are involved in tick survival and pathogen infection and multiplication. however, the gene expression profile in a. phagocytophilum-infected tick cells is currently poorly characterized. the objectives o ... | 2009 | 19636428 |
| 'nothing is permanent but change'- antigenic variation in persistent bacterial pathogens. | pathogens persist in immunocompetent mammalian hosts using various strategies, including evasion of immune effectors by antigenic variation. among highly antigenically variant bacteria, gene conversion is used to generate novel expressed variants from otherwise silent donor sequences. recombination using oligonucleotide segments from multiple donors is a combinatorial mechanism that tremendously expands the variant repertoire, allowing thousands of variants to be generated from a relatively smal ... | 2009 | 19709057 |
| phylogeographic analysis reveals association of tick-borne pathogen, anaplasma marginale, msp1a sequences with ecological traits affecting tick vector performance. | the tick-borne pathogen anaplasma marginale, which is endemic worldwide, is the type species of the genus anaplasma (rickettsiales: anaplasmataceae). rhipicephalus (boophilus) microplus is the most important tick vector of a. marginale in tropical and subtropical regions of the world. despite extensive characterization of the genetic diversity in a. marginale geographic strains using major surface protein sequences, little is known about the biogeography and evolution of a. marginale and other a ... | 2009 | 19723295 |
| seroprevalence of tick-borne diseases in communal cattle reared on sweet and sour rangelands in a semi-arid area of south africa. | a survey was conducted to determine the seroprevalence of tick-borne diseases (tbd) in nguni and non-descript cattle on the sweet and sour communal rangelands across seasons. body condition scores, bodyweights, packed cell volume (pcv) and antibodies to b. bovis, b. bigemina, ehrlichiaruminatium and anaplasma marginale were determined seasonally in 144 cattle raised on communal rangelands from august 2007 to april 2008. approximately 45% of the cattle were seropositive for b. bovis, 46% for b. b ... | 2010 | 19733490 |
| thymidylate kinase: the lost chemotherapeutic target. | here we highlight the unusual substrate specificity of plasmodium falciparum thymidylate kinase (pftmk) and the validity of the enzyme as a new drug target. furthermore, we predict that the anaplasma marginale enzyme has attractive domain constituents and may be functionally different from other tmpks. we postulate that thymidylate kinases could have multiple attractive functions in pathogens and may be a new drug target against numerous microorganisms. | 2009 | 19749371 |
| molecular epidemiology of bovine anaplasmosis with a particular focus in mexico. | bovine anaplasmosis, caused by the rickettsia anaplasma marginale, has a worldwide distribution and is the cause of great economic losses in developing countries where it is highly endemic. transmission is carried mainly by ixodid ticks: dermacentor spp. and rhipicephalus (boophilus) spp. mechanical transmission is important in disseminating the disease within and across herds. the relationship between the rickettsia, the host and the vector is complex. several surface proteins (msps) have been ... | 2009 | 19786123 |
| the natural history of anaplasma marginale. | the intracellular pathogen anaplasma marginale (rickettsiales: anaplasmataceae), described by sir arnold theiler in 1910, is endemic worldwide in tropical and subtropical areas. infection of cattle with a. marginale causes bovine anaplasmosis, a mild to severe hemolytic disease that results in considerable economic loss to both dairy and beef industries. transmission of a. marginale to cattle occurs biologically by ticks and mechanically by biting flies and by blood-contaminated fomites. both ma ... | 2010 | 19811876 |
| transformation of anaplasma marginale. | the tick-borne pathogen, anaplasma marginale, has a complex life cycle involving ruminants and ixodid ticks. it causes bovine anaplasmosis, a disease with significant economic impact on cattle farming worldwide. the obligate intracellular growth requirement of the bacteria poses a challenging obstacle to their genetic manipulation, a problem shared with other prokaryotes in the genera anaplasma, ehrlichia, and rickettsia. following our successful transformation of the human anaplasmosis agent, a ... | 2010 | 19837516 |
| protection in the absence of exclusion between two brazilian isolates of anaplasma marginale in experimentally infected calves. | this study investigated whether a low pathogenicity isolate of anaplasma marginale with an appendage (ufmg1) could protect calves from infection with a pathogenic a. marginale isolate (ufmg2). two groups of five friesian calves were each inoculated with ufmg1 by intravenous injections of either a. marginale-infected tick cell cultures (group 1) or blood stabilates (group 2); a third (control) group was injected with saline. all animals were inoculated with a blood stabilate containing a high pat ... | 2010 | 19837622 |
| complete genome sequence of anaplasma marginale subsp. centrale. | anaplasma marginale subsp. centrale is a naturally attenuated subtype that has been used as a vaccine for a century. we sequenced the genome of this organism and compared it to those of virulent senso stricto a. marginale strains. the comparison markedly narrows the number of outer membrane protein candidates for development of a safer inactivated vaccine and provides insight into the diversity among strains of senso lato a. marginale. | 2010 | 19854912 |
| sir arnold theiler and the discovery of anaplasmosis: a centennial perspective. | sir arnold theiler's research in 1908/09 led to the discovery of the first rickettsial pathogen, anaplasma marginale, and set the stage for his development and implementation of an effective live vaccine based on a less virulent strain, a. marginale ss. centrale. his 1910 report, describing a. marginale, is among the classic monographs in infectious disease research, presenting not only observations in exacting detail but also highlighting the deductive reasoning leading to association of a new ... | 2009 | 19967931 |
| a new pcr-rflp method for detection of anaplasma marginale based on 16s rrna. | species of the genus anaplasma (rickettsiales: anaplasmataceae) are obligate intracellular tick borne pathogens. three species of anaplasma that infect cattle and sheep (a. marginale, a. centrale and a. ovis) are well recognized. of these erythrocytic anaplasma, a. marginale can cause diseases in the livestock with high economical losses. species-specific pcr based on 16s rrna gene is commonly used for detection of anaplasma species but can not differentiate a. marginale, a. centrale and a. ovis ... | 2010 | 20013050 |
| identification of anaplasma centrale major surface protein-2 pseudogenes. | the present study was aimed to identify msp2 pseudogenes and msp2 variants in the vaccine anaplama centrale strain. five msp2 pseudogenes were identified in the a. centrale genome, and multiple msp2 variants that emerged during both acute and persistent infection were detected. the pseudogene copies of msp2 were truncated; they contained a central hypervariable region flanked by short portions of the 5' and 3' conserved regions. alignment of the hypervariable region sequence of the expression si ... | 2010 | 20036077 |
| [effects of the oxitetracycline in the increase of the packed cell volume of cows milk jugs during outbreak of bovine anaplasmosis]. | this research was performed to study the effects of oxytetracicline l.a., in unique dose, in the reconstitution of the packed cell volume (pcv) from animals clinically affected by anaplasmosis. were utilized 152 holstein frisian cows, of first lactation with age group varying between three and four years old. the animals were classified according to the presence of anaplasma marginale in the circulation and percentage of pcv as: chronic infection (pcve24%) and clinical (pcv<23%) constituting gro ... | 2008 | 20059824 |
| anaplasma marginale type iv secretion system proteins virb2, virb7, virb11, and vird4 are immunogenic components of a protective bacterial membrane vaccine. | anaplasma and related ehrlichia spp. are important tick-borne, gram-negative bacterial pathogens of livestock and humans that cause acute infection and disease and can persist. immunization of cattle with an anaplasma marginale fraction enriched in outer membranes (om) can provide complete protection against disease and persistent infection. serological responses of om vaccinees to the om proteome previously identified over 20 antigenic proteins, including three type iv secretion system (t4ss) p ... | 2010 | 20065028 |
| subolesin expression in response to pathogen infection in ticks. | ticks (acari: ixodidae) are vectors of pathogens worldwide that cause diseases in humans and animals. ticks and pathogens have co-evolved molecular mechanisms that contribute to their mutual development and survival. subolesin was discovered as a tick protective antigen and was subsequently shown to be similar in structure and function to akirins, an evolutionarily conserved group of proteins in insects and vertebrates that controls nf-kb-dependent and independent expression of innate immune res ... | 2010 | 20170494 |
| the immunization-induced antibody response to the anaplasma marginale major surface protein 2 and its association with protective immunity. | many vector-borne pathogens evade clearance via rapid variation in their immunogenic surface expressed proteins. this is exemplified by anaplasma marginale, a tick-borne bacterial pathogen that generates major surface protein 2 (msp2) variants to provide for immune escape and allow long-term pathogen persistence. in contrast to persistence following infection, immunization with a surface protein complex, which includes msp2, induces a response that prevents infection upon challenge. we hypothesi ... | 2010 | 20199762 |
| an indirect elisa for detection of theileria sergenti antibodies in water buffalo using a recombinant major piroplasm surface protein. | in this study we investigated the prevalence and enzootic potential of theileria spp. in water buffalo in the hubei province in china. an indirect elisa based on a recombinant major piroplasma surface protein was developed. the complete orf of the 33-kda major piroplasma surface protein (p33) was obtained from theileria sergenti genomic dna by pcr, cloned into the pet-28(a) vector and expressed in e. coli as a his-fusion protein. then the recombinant p33 (rp33) was purified and used as the antig ... | 2010 | 20207484 |
| diagnostic accuracy of methods for detecting anaplasma marginale infection in lactating dairy cattle of puerto rico. | bovine anaplasmosis (ba) is a hemoparasitic disease of great importance in cattle within the tropical and subtropical regions of the world. control programs for ba require accurate diagnostic assays but validation can be challenging because the true disease status of all animals is frequently not known with certainty. the objective of this study was to estimate the accuracy of assays for detection of anaplasma marginale infection in lactating dairy cattle of puerto rico using bayesian methods wi ... | 2010 | 20224076 |
| differential expression of genes in salivary glands of male rhipicephalus (boophilus)microplus in response to infection with anaplasma marginale. | bovine anaplasmosis, caused by the rickettsial tick-borne pathogen anaplasma marginale (rickettsiales: anaplasmataceae), is vectored by rhipicephalus (boophilus)microplus in many tropical and subtropical regions of the world. a. marginale undergoes a complex developmental cycle in ticks which results in infection of salivary glands from where the pathogen is transmitted to cattle. in previous studies, we reported modification of gene expression in dermacentor variabilis and cultured ixodes scapu ... | 2010 | 20298599 |
| association of pathogen strain-specific gene transcription and transmission efficiency phenotype of anaplasma marginale. | efficient transmission of pathogens by an arthropod vector is influenced by the ability of the pathogen to replicate and develop infectiousness within the arthropod host. while the basic life cycle of development within and transmission from the arthropod vector are known for many bacterial and protozoan pathogens, the determinants of transmission efficiency are largely unknown and represent a significant gap in our knowledge. the st. maries strain of anaplasma marginale is a high-transmission-e ... | 2010 | 20308303 |
| the efficacy of three chlortetracycline regimens in the treatment of persistent anaplasma marginale infection. | chemosterilization is reported in cattle fed chlortetracycline hydrochloride (ctc) at dosages ranging from 1.1mg/kg for 120 days to 11 mg/kg for 30-60 days. the relationship between plasma ctc drug concentration and carrier clearance has not been described. chronic carrier status was established in 21 steers with a virginia isolate of anaplasma marginale and confirmed by celisa and an a. marginale-specific rt-pcr. four negative, splenectomized steers served as active disease transmission sentine ... | 2010 | 20346598 |
| characterization of anaplasma phagocytophilum and a. ovis infection in a naturally infected sheep flock with poor health condition. | anaplasma species are transmitted by ticks and cause diseases in humans and animals. these pathogens infect sheep, an economically important domestic animal worldwide. the current study was designed to characterize in 200 animals the infection with anaplasma phagocytophilum and anaplasma ovis and the genetic diversity of a. ovis strains collected from a naturally infected sheep flock with poor health condition. sheep had 98% seroprevalence to anaplasma spp. antibodies. pcr results confirmed the ... | 2010 | 20405320 |
| estimating seroprevalence and variation to four tick-borne infections and determination of associated risk factors in cattle under traditional mixed farming system in mbeere district, kenya. | a cross-sectional study of serum antibody responses of cattle to tick-borne disease (tbd) parasites (theileria parva, theileria mutans, anaplasma marginale and babesia bigemina) was conducted on traditional smallholder mixed farms in mbeere district in kenya. the objective was to estimate the infections' seroprevalence and variation and identify associated risk factors. a total of 440 cattle in 80 farms, selected by stratified random sampling from the four divisions in the district, were surveye ... | 2010 | 20434227 |
| identification of anaplasma marginale proteins specifically upregulated during colonization of the tick vector. | the transition between infection of the mammalian host and colonization of an arthropod vector is required for the ongoing transmission of a broad array of pathogens, from viruses to protozoa. understanding how this transition is mediated provides opportunities to disrupt transmission through either chemotherapy or immunization. we used an unbiased proteomic screen to identify anaplasma marginale proteins specifically upregulated in the tick compared to the mammalian host. comparative mass spect ... | 2010 | 20439479 |