| babesia rodhaini, babesia bovis, and babesia bigemina: analysis and sorting of red cells from infected mouse or calf blood by flow fluorimetry using 33258 hoechst. | | 1979 | 92419 |
| kinin, kininogen and kininase levels during acute babesia bovis (= b. argentina) infection of cattle. | 1. kinin levels began rising on day 3 after infection of cattle with babesia bovis (= b. argentina) and attained a maximum value of 98% above preinfection levels by day 7. 2. kininogen levels began falling on day 3 and reached minimum levels of 83% below preinfection levels on day 8. 3. changes in both kinin and kininogen levels on day 3 coincided with the detection of low levels of parasites, and with a fall in packed cell volume. 4. plasma kininase levels rose significantly 6 to 9 days after i ... | 1977 | 202358 |
| bovine babesiosis: vaccination against tick-borne challenge exposure with culture-derived babesia bovis immunogens. | | 1979 | 230765 |
| a note on the transmission of babesia bovis (syn b argentina) by the one-host tick, boophilus microplus. | boophilus microplus infected with babesia bovis were transferred artificially from one splenectomised calf to another during each moult in the parasitic life cycle of the tick. eggs from the engorged female ticks recovered at the end of the cycle were incubated and the resulting larvae used to infest more splenectomised calves. babesia bovis was transmitted only by the original larvae used at the commencement of the experiment and it was concluded that the protozoan parasite did not persist in a ... | 1979 | 262611 |
| babesia bovis (argentina): components of the cryofibrinogen complex and their contribution to pathophysiology of infection in splenectomized calves. | a cryofibrinogen complex, found in the plasma of cattle acutely infected with babesia bovis (argentina), was characterized. the fibrinogen-like proteins of the complex were isolated and the structure of their polypeptide chains analysed. in general, the chain structure was similar to that of soluble non-crosslinked fibrin (fibrinogen) although chains indicating some degree of fibrin crosslinking were often detected. only rarely did the chain structure suggest that fibrinolysis occurred. it was c ... | 1978 | 369166 |
| some aspects of the epidemiology and control of bovine babesiosis in australia. | a short account of the epidemiology and control of babesiosis in australia is presented. epidemiological topics discussed include differences in the transmission of babesia bovis and b. bigemina by the cattle tick, boophilus microplus and the relative prevalence, disease incidence and pathogenicity of b. bovis and b. bigemina. circumstances under which babesiosis occurs in australia are described. in the section on control, only vaccination is discussed. changes in the preparation of babesial va ... | 1979 | 399977 |
| immunity in cattle to babesia bovis after single infections with parasites of various origin. | sixty calves, 3 to 6 months old, were vaccinated once against babesia bovis in groups of 10, by the following methods: (a) tick infestation; (b) inoculation of virulent parasites obtained from the tick-infested animals immediately after infection; (c) inoculation of the parasites used in (b) attenuated by passage through splenectomised calves; (d) inoculation of commercially-available, living, attenuated vaccine; (e) inoculation of virulent parasites obtained from the tick-infested animals in (a ... | 1979 | 435202 |
| an electron microscopic study of intra-erythrocytic stages of babesia bovis in the brain capillaries of infected splenectomized calves. | splenectomized vaccine donor calves undergoing primary reactions to babesia bovis infections may develop cerebral babesiosis which leads to death if not treated in time. a brain biopsy was performed on an artificially-infected animal showing nervous symptoms and the tissue was immediately processed for electron microscopic examination. virtually every erythrocyte in the brain capillaries sectioned was infected with b. bovis. intra-erythrocytic merozoites, trophozoites and dividing trophozoites w ... | 1979 | 460822 |
| the invasion and growth of babesia bovis in tick tissue culture. | erythrocytic forms of babesia bovis inoculated into cell cultures of the tick boophilus microplus invaded the tick cells and showed multiplication for up to 48 h after inoculation. | 1979 | 467577 |
| the immune response of cattle to babesia bovis (syn. b. argentina). studies on the nature and specificity of protection. | | 1979 | 489236 |
| reduction in virulence of babesia bovis due to rapid passage in splenectomized cattle. | | 1979 | 489240 |
| acute babesia bovis infections: renal involvement in the hypotensive syndrome. | splenectomised calves in metabolism cages were infected with babesia bovis. during the infection, urine samples were collected and analysed for electrolytes, proteins, kinin, and urinary kallikrein. during the later stages of the infection there were significant reductions in urinary volume, water intake, urinary kinin, kallikrein, and electrolytes. proteinuria was detected from 3--8 days postinfection of which 15--20% was haemoglobin and most of the remainder was albumin (70--75%). fibrin degra ... | 1979 | 494708 |
| bovine babesiosis: partial purification and characterization of blood culture-derived babesia bovis. | | 1979 | 541171 |
| babesia bovis (argentina): analysis of fibrinogen-like proteins during infection. | fibrinogen and fibrinogen-like proteins (flp) were isolated from plasma and serum of cattle acutely infected with babesia bovis. the sizes and chain structures of these proteins were examined and clotting assays performed. the results indicated that the blood was in a hypercoagulable state due mainly to enhanced production of hydrogen bonded fibrin and offset partly by slight inhibition of chain cross-linking. the latter appeared due to a factor xiii inhibitor. reduction of a alpha chains of pla ... | 1979 | 543211 |
| preliminary observations on the combined use of imidocarb and babesia blood vaccine in cattle. | imidocarb was used by three different methods to control reactions in cattle induced by a babesia blood vaccine produced in south africa. simultaneous administration of 0,15 mg/kg imidocarb and babesia bovis vaccine gave satisfactory control. when the vaccine was given seven days prior to the imidocarb treatment a dose between 0,15 mg/kg and 0,6 mg/kg imidocarb was required for effective control. a combined b. bovis and babesia bigemina vaccine given at 21 and again 61 days after a 3 mg/kg imido ... | 1979 | 553972 |
| epidemiology and control of bovine babesiosis in south africa. | babesiosis is the cause of serious economic losses in south africa and involves most areas with an annual rainfall of more than 400 mm. both babesia bigemina and babesia bovis are present and both are considered to be important. the vectors, distribution and factors influencing enzootic stability of both species are discussed. except in some areas only marginally suitable for ticks, and where tick control alone may be adequate, control by immunisation is recommended. short term prevention can be ... | 1979 | 576018 |
| failure of vaccine strains of babesia bovis to regain infectivity for ticks during long-standing infections in cattle. | two strains of babesia bovis that were known to have lost infectivity for the normal tick vector, boophilus microplus, due to repeated blood passaging in cattle, were studied to determine whether the strains would regain infectivity for ticks during longstanding infections. parasitaemias were monitored in 4 chronically infected calves that were regularly infested with ticks. two strains of ticks known to be susceptible to infection with unmodified strains of b. bovis were used. adult female tick ... | 1977 | 588177 |
| hypotension in acute babesia bovis (=b. argentina ) infections of splenectomized calves. | | 1977 | 591652 |
| babesia bovis (argentina): observations of coagulation parameters, fibrinogen catabolism and fibrinolysis in intact and splenectomized cattle. | the results of this paper indicate that cattle infected with b. bovis (argentina) have a markedly altered and activated coagulation system. a degree of thrombin activation occurs due partly to release of thromboplastin-like substances from lysed erythrocytes but due primarily to activation of kallikrein by babesial proteases. this produces a hyperfibrinogenaemia, particularly in intact cattle, with soluble fibrin complexes constituting up to one-third of the total fibrinogen concentration. high ... | 1977 | 602370 |
| immunosuppression by babesia bovis against its tick vector, boophilus microplus. | | 1978 | 643072 |
| babesia bovis (= argentina): changes in erythrophylic and associated proteins during acute infection of splenectomized and intact calves. | saline eluates were prepared from sucrose-washed erythrocytes of cattle infected with b. bovis (= argentina). fibrinogen, plasminogen and igg2 were constituent proteins of the eluates and all three proteins increased in concentration during infection. the significance of the protein changes and their contribution to coagulation and fibrinolysis during infection are discussed. | 1978 | 654424 |
| bovine babesiosis: severity and reproducibility of babesia bovis infections induced by boophilus microplus under laboratory conditions. | a total of 61 intact holstein-friesian calves were exposed to babesia bovis (= b argentina) by the injection of infected blood or the application of infected boophilus microplus larvae. tick-induced infections were uniformly severe, even when induced by relatively small numbers of infected ticks. in contrast, calves infected with carrier blood experienced mild, subclinical reactions despite detectable parasitaemia. the greater severity of tick-induced reactions appeared to be due to the large nu ... | 1978 | 674841 |
| the effect of age on resistance of cattle to babesia bovis. | susceptible hereford cattle of different ages were inoculated with 2 x 10(8) babesia bovis organisms. experiment i consisted of cows aged 6 to 7 years, steers aged 17 to 18 months and calves aged 5 to 6 months, while experiment 2 consisted of cows aged 6.5 to 7.5 years, steers aged 23 to 24 months and yearlings aged 11 to 12 months. daily measurements of temperature, parasitaemia and packed cell volume were made in order to determine susceptibility of the different ages. twenty-four of the 36 an ... | 1978 | 687298 |
| the presence of babesia bovis (b. argentina) in paraguay. | | 1978 | 705899 |
| immunogenicity and pathogenicity of three south african strains of babesia bovis in bos indicus cattle. | a strain of babesia bovis, which has been routinely used in the locally produced babesiosis vaccine for two decades and maintained by needle passage, was of low virulence and therefore safe, but it induced poor protection to challenge with two field isolates. animals infected with this attenuated strain and subsequently challenged heterologously with a field strain were solidly immune when challenged later with a 2nd field strain. the two field strains, though more virulent, conferred a high deg ... | 1978 | 714391 |
| growth of babesia bovis in bovine erythrocyte cultures. | babesia bovis was cultured in a suspension of bovine erythrocytes incubated at 37 degrees c in medium 199 with 50% bovine serum. the cells in culture were kept in suspension by slow stirring in spinner flasks and the medium was replaced at 24-hour intervals. persistent multiplication of the parasite in a short series of subcultures suggests the feasibility of this approach for continuous culture. | 1978 | 717633 |
| differences in the life cycles between a vaccine strain and an unmodified strain of babesia bovis (babes, 1889) in the tick boophilus microplus (canestrini). | developmental forms of 2 strains of babesia bovis (babes) were studied in the tick vector boophilus microplus (canestrini). one strain (designated t) was shown to be infective for the tick, and the other (nt) to have lost infectivity for the tick, because of repeated blood passaging in cattle. parasites of the 2 strains in gut contents of adult female ticks were similar during the first 16 h post-repletion (pr), but thereafter their structure differed. from 16-64 h pr, the majority of t strain p ... | 1978 | 739414 |
| the extraction of infective babesia bovis and babesia bigemina from tick eggs and b. bigemina from unfed larval ticks. | | 1978 | 743062 |
| the protamine sulphate test as a screening test for intravascular coagulation in experimental babesia bovis infections. | the protamine sulphate test (pst) was studied as a screening test for intravascular coagulation in experimental babesia bovis infections. the test became positive in 39 of 42 splenectomised calves and two of six intact cattle tested during acute infections. haematological studies during the course of infection in two splenectomised and six intact cattle indicated that a positive pst was reliable evidence for intravascular coagulation. of four splenectomised and one intact cattle that were positi ... | 1977 | 905640 |
| the selection of larvae of boophilus microplus infected with babesia bovis (syn b argentina). | observations on the dynamics of the transovarial transmission of babesia bovis by boophilus microplus showed that, at 28 degrees c and 90--95 per cent relative humidity, a low proportion of the eggs laid during the first five days' incubation of the engorged female ticks were infected with the babesia. however, the eggs laid on the sixth and seventh days of incubation were heavily infected. this was the basis of a method for selecting larval cultures of b microplus which contained up to five tim ... | 1977 | 905646 |
| the fine structure of merozoites of babesia bovis in the gut epithelium of boophilus microplus. | electron microscopic studies on merozoites of babesia bovis in epithelial cells of the gut of boophilus microplus revealed that the pellicle apparently consists of 3 membranes, and an osmiophilic layer intimately associated with microtubules. micropores in the pellicle were often associated with micronemes. an unidentified tubular structure extended from the anterior polar ring to the nuclear region where it appeared to be associated with the nuclear envelope. a golgi complex, typical protozoan ... | 1976 | 940662 |
| light and electron microscopic observations on the development of small merozoites of babesia bovis in boophilus microplus larvae. | the development of small pyriform merozoites of b. bovis in the granule-secreting cells of the salivary glands of b. microplus larvae, studied with a light microscope, showed a close resemblance to that of b. argentina described by riek (1966) in the same tick vector. dvelopment took place through a process of schizogony and resulted in the formation of many merozoites. a study of the ultrastructure of developing merozoites in the schizont revealed the following: a poorly defined outer membrane; ... | 1976 | 1012651 |
| stimulation of the development of infective babesia bovis (= b. argentina) in unfed boophilus microplus larvae. | | 1976 | 1016162 |
| cerebral babesiosis in a new-born calf. | a case of intra-uterine transmission of babesia bovis is reported. the calf was born normally but showed signs of intravascular haemolysis and nervous involvement 24 h after birth. it died shortly afterwards from cerebral babesiosis. the dam was not clinically affected. | 1976 | 1018892 |
| surface epitope localization and gene structure of a babesia bovis 44-kilodalton variable merozoite surface antigen. | variation of babesia bovis merozoite surface antigens occurs among geographic strains of the parasite. in this and a concurrent report, we investigate this variation at the gene and protein level. using a monoclonal antibody (mab 23/70.174), b. bovis gene sequences were identified that encoded a surface epitope of a 44-kda merozoite surface antigen (msa-2). this epitope is variably expressed among geographic isolates of b. bovis. here, we describe the msa-2 protein gene sequence, localize this s ... | 1992 | 1279420 |
| neutralization-sensitive merozoite surface antigens of babesia bovis encoded by members of a polymorphic gene family. | monospecific antibodies against native and recombinant versions of the major merozoite surface antigen (msa-1) of babesia bovis neutralize the infectivity of merozoites from texas and mexico strains in vitro. sequence analysis shows that msa-1 and a related, co-expressed 44 kda merozoite surface protein (msa-2) are encoded by members of a multigene family previously designated babr. babr genes, originally described in australia strains of b. bovis, are notable because their marked polymorphism i ... | 1992 | 1279421 |
| [determination of the protease activity in a cuban strain of babesia bovis]. | the attenuation of a babesia bovis strain depends on its protease content. the present work evaluates this parameter on a virulent strain, before and after attenuation by quick passages on splenectomized calves. the protease activity at different ph values was determined in protein fractions from the blood of calves. the enzymatic test showed marked differences between the protease content of both substrains. | 1992 | 1298023 |
| [current status of bovine haemoparasitic diseases in martinique (french west indies)]. | a serological survey using indirect immunofluorescence (ifat) for bovine babesiosis (babesia bovis and b. bigemina) and card test for anaplasmosis, indicates that these haemoparasites are widespread in martinique. the high prevalences (62% for b. bovis, 52% for b. bigemina and 43% for anaplasma marginale) lead to the hypothesis of an unstable epizootic situation for these three haemoparasitic diseases. however, the number of smears examined was too low to evaluate their clinical incidence. both ... | 1992 | 1298026 |
| prevalence of babesia bovis and anaplasma marginale at selected localities in sri lanka. | sera were collected from a minimum of 20 cattle aged nine to 36 months at each of 14 localities in five climatic zones of sri lanka. sera were tested for antibodies to babesia bovis and anaplasma by an indirect fluorescent antibody test and a card agglutination test, respectively. antibodies to b. bovis and anaplasma were detected in all samples tested from each of 14 and 12 localities respectively. in general, prevalences were consistently high among localities below 1,200 m and lower and more ... | 1992 | 1306921 |
| extrachromosomal nucleic acids in bovine babesia. | two kinds of small extrachromosomal nucleic acid elements were found in the bovine babesias, babesia bovis and b. bigemina. one element with an apparent size of 5.5 kilobase pairs (kbp) is a double stranded rna related to virus like particles. another molecule is a double stranded dna with a molecular size of about 6.2 kbp. southern blot comparison of restriction dna fragments of the latter molecule, which is present in both b. bovis and b. bigemina is described. | 1992 | 1343677 |
| impact of babesia bovis and babesia bigemina on the production of beef cattle in uruguay. | uruguay is situated in a marginal area for the development of boophilus microplus (30 degrees 35 degrees south lat.) with important areas of enzootic instability for babesia bovis and b. bigemina. the livestock products represent 70% of our exports, for which reason it is fundamental to evaluate the losses in the production that these haemoparasites cause as basic information to take future decisions. in the period 1988-1990, several works were carried out by our laboratory to know the incidence ... | 1992 | 1343684 |
| non-immunologic methods of diagnosis of babesiosis. | the diagnosis of tick-borne diseases such as babesiosis still depends on observing the parasite in the infected erythrocyte. microscopic observation is tedious and often problematic in both early and carrier infections. better diagnostic methods are needed to prevent clinical disease, especially when susceptible cattle are being moved into disease enzootic areas. this study evaluates two techniques for early diagnosis of babesia bovis infections in cattle, dna probes specific for the organism an ... | 1992 | 1343690 |
| polypeptides reactive with antibodies eluted from the surface of babesia bovis-infected erythrocytes. | a technique was sought that would enable identification of surface-exposed parasite antigens on babesia bovis-infected erythrocytes (bbie) that are not detectable by surface-specific immunoprecipitations. antibodies which bind to the surface of bbie were recovered from intact cells using a low ph wash procedure. the eluted antibodies were then used in conventional immunoprecipitation assays to identify parasite-synthesized polypeptides carrying epitopes that are exposed on the surface or are cro ... | 1992 | 1343693 |
| a rapid, reliable method of evaluating growth and viability of intraerythrocytic protozoan hemoparasites using fluorescence flow cytometry. | fluorescence flow cytometry was employed to assess the potential of a vital dye, hydroethidine, for use in the detection and monitoring of the viability of hemoparasites in infected erythrocytes, using babesia bovis as a model parasite. the studies demonstrated that hydroethidine is taken up by b. bovis and metabolically converted to the dna binding fluorochrome, ethidium. following uptake of the dye, erythrocytes containing viable parasites were readily distinguished and quantitated. timed stud ... | 1992 | 1343696 |
| prevalence and control of babesiosis in the americas. | this review presents up-to-date information on the distribution and control measures of babesiosis in latin america. bovine babesiosis caused by babesia bovis and b. bigemia will be emphasized. the disease is endemic in most countries and poses a serious economic burden on livestock production in the region (u.s. $1365 million/year, fao, 1989). of the estimated 250 million cattle in central and south america, approximately 175 million (70%) are in tick-infested regions. humid, tropical and subtr ... | 1992 | 1343700 |
| field evaluation of an exoantigen-containing babesia vaccine in venezuela. | bovine babesiosis is endemic in venezuela, causing significant losses in highly susceptible imported cattle. current immunoprophylactic methods include the less desirable use of live parasites. inactivated vaccines derived from exoantigen-containing supernatant fluids of in vitro babesia bovis and b. bigemina cultures have been developed and constitute a major improvement in vaccine safety, stability and ease of handling. vaccination trials conducted under field conditions provide the final eval ... | 1992 | 1343704 |
| successful vaccination against boophilus microplus and babesia bovis using recombinant antigens. | current methods for the control of the cattle tick boophilus microplus and the agent of bovine babesiosis, babesia bovis are unsatisfactory. effective immunological control of both parasites would have great advantages. however, naturally acquired immunity to the tick is generally unable to prevent serious production losses. a vaccine against the tick, based on a novel form of immunization, is being developed. a protective antigen has been isolated from the tick, characterized and produced as an ... | 1992 | 1343705 |
| a study on the pathogenesis of human cerebral malaria and cerebral babesiosis. | cerebral complications are important, but poorly understood pathological features of infections caused by some species of plasmodium and babesia. patients dying from p. falciparum were classified as cerebral or non-cerebral cases according to the cerebral malaria coma scale. light microscopy revealed that cerebral microvessels of cerebral malaria patients were filled with a mixture of parasitized and unparasitized erythrocytes, with 94% of the vessels showing parasitized red blood cell (prbc) se ... | 1992 | 1343706 |
| molecular approaches to malaria and babesiosis diagnosis. | the development of additional methods for detecting and identifying babesia and plasmodium infections may be useful in disease monitoring, management and control efforts. the preliminary evaluate synthetic peptide-based serodiagnosis, a hydrophilic sequence (ddesefdkek) was selected from the published babr gene of b. bovis. immunization of rabbits and cattle with the hemocyanin-conjugated peptide elicited antibody responses that specifically detected both p. falciparum and b. bovis antigens by i ... | 1992 | 1343727 |
| babesia bovis: bovine helper t cell lines reactive with soluble and membrane antigens of merozoites. | babesia bovis-specific t cell lines were established from cattle infected with either tick-derived or cultured parasites by stimulation of peripheral blood mononuclear cells with a crude parasite membrane fraction. induction and enrichment of cd4+ t cells occurred over time. all cell lines responded vigorously and in a dose-dependent, mhc-restricted manner to intact merozoites, and to soluble and membrane fractions derived from merozoites by homogenization and high-speed centrifugation. solubili ... | 1992 | 1371257 |
| a babesia bovis 225-kilodalton protein located on the cytoplasmic side of the erythrocyte membrane has sequence similarity with a region of glycogen phosphorylase. | a babesia bovis gene sequence is described which encodes a geographically conserved epitope (recognized by monoclonal antibody (mab) 23.8.34) of a 225-kda protein located on the surface of merozoites and associated with the infected erythrocyte membrane. the gene sequence, derived from both genomic and cdna copies, is 2044 bp long and has one long open reading frame encoding about one third of the 225-kda protein. the open reading frame is expressed in an approximately 6,400 nucleotide rna trans ... | 1992 | 1377786 |
| bovine helper t cell clones recognize five distinct epitopes on babesia bovis merozoite antigens. | helper t cell clones from two babesia bovis-immune cattle were characterized for use in identification of potentially protective immunogens of b. bovis merozoites. proliferation assays with 11 cd4+ clones revealed a differential pattern of response to soluble cytosolic antigen, membrane-enriched antigen, detergent extracts of the membrane-enriched antigen, soluble culture supernatant exoantigen, and different geographical isolates of b. bovis as well as babesia bigemina parasites. when the data ... | 1992 | 1383149 |
| serological and immunological studies with a hexane extract of babesia bovis-infected erythrocytes. | antigenic and immunogenic activities of a hexane extract from babesia bovis-infected erythrocytes were investigated. positive elisa and ifat reactions were obtained with bovine antisera to b. bovis and b. bigemina produced by natural infection and rabbit antisera to the hexane extract, respectively. in contrast, negative elisa reactions were obtained with anaplasma marginale antisera indicating that the antigen(s) is specific for the genus babesia. the ifat clearly demonstrated that the antigen ... | 1992 | 1383165 |
| detection of babesia bigemina-infected carriers by polymerase chain reaction amplification. | a spei-avai fragment (0.3 kbp) from pbbi16 (a pbr322 derivative containing a 6.3-kbp babesia bigemina dna insert) was subcloned into the pbluescript phagemid vector and was sequenced by the dideoxy-mediated chain termination method. two sets of primers were designed for the polymerase chain reaction (pcr) assay. primer set ia-ib was used to amplify a 278-bp dna fragment, and primer set ian-ibn was used to prepare a probe directed to a site within the pcr-amplified target dna. digoxigenin-dutp wa ... | 1992 | 1400956 |
| the effect of neutrophils, tumor necrosis factor, and granulocyte macrophage/colony stimulating factor on babesia bovis and babesia bigemina in culture. | bovine neutrophils, human recombinant tumor necrosis factor-alpha (tnf), and bovine recombinant granulocyte macrophage/colony stimulating factor (gm/csf) were added to microaerophilic cultures of babesia bovis and babesia bigemina to determine if those substances could inhibit growth. incorporation of [3h]hypoxanthine by the babesia spp. was utilized as an indirect measure of parasite growth. when neutrophils were added to cultures of b. bovis and b. bigemina, the highest percentage inhibition o ... | 1992 | 1413450 |
| analysis of the composition of samples of babesia bovis and the influence of different environmental conditions on genetically distinct subpopulations. | a recombinant dna probe specific for a tandemly repeated sequence located within the bova1 gene of babesia bovis was used to analyse 10 independent samples of b. bovis. twelve different alleles of the bova1 gene and flanking regions were identified in the 18 different subpopulations analysed. most samples of b. bovis originally derived from single animals contained more than one genetically distinct subpopulation. however, only one population of parasites was identified in samples of the ka line ... | 1992 | 1428506 |
| babesia bovis, babesia bigemina, babesia canis, babesia microti and babesia rodhaini: comparison of ribosomal rna gene organization. | the three ribosomal dna (rdna) units have been cloned from an australian isolate of babesia bigemina. the organization of the units is very similar to that reported for a mexican isolate of b. bigemina. in babesia canis four rdna units have been identified. both babesia rodhaini and babesia microti contain two different rdna units. a small number of different rdna units appears to be a common feature of this group of protozoa. restriction enzyme analysis of the rdna units form these species and ... | 1992 | 1428519 |
| the development of a recombinant babesia vaccine. | crude extracts of babesia bovis parasites were shown to induce levels of protection in susceptible cattle equivalent to that resulting from natural infection. the crude material was systematically fractionated and tested in numerous sequential vaccination/challenge experiments in adult cattle. antigens in protective fractions were then purified by affinity chromatography with monoclonal antibodies. three highly protective (more than 95% reduction in parasitaemias) antigens were thus identified. ... | 1992 | 1441189 |
| characterisation of genes encoding two novel members of the aldo-keto reductase superfamily. | the predicted amino acid sequence of the protein encoded by a cdna clone isolated from the protozoan haemoparasite babesia bovis has approximately 22% amino acid identity with the pichia stipitis xylose reductase. there are similar levels of amino acid identity with other members of the aldo-keto reductase superfamily. the identities include many residues highly conserved in the superfamily. however, the amino acid sequence of the b. bovis protein (akr1) clearly lies outside the cluster of the p ... | 1992 | 1482401 |
| human serum for in vitro cultivation of babesia bovis. | various combinations of human serum (from blood of groups a and rhesus positive) with bovine serum, i.e. 20% + 20% (medium i), 30% + 10% (ii), 40% + 0% (iii) and 0% + 40% (iv) and medium-199 (60%) were used in the propagation of babesia bovis. babesia bovis stabilate revived by inoculation in a bovine calf was used at a level of 6% parasitized erythrocytes (ppe). the medium was replenished every 24 h. the medium changed from bright red to dark-coffee color every 24 h. the increase in ppe was max ... | 1992 | 1485417 |
| computer simulation of babesia bovis (babes) and b. bigemina (smith & kilborne) transmission by boophilus cattle ticks (acari: ixodidae). | a computer model was developed to simulate the processes involved in transmission of the cattle fever parasites babesia bovis (babes) and babesia bigemina (smith & kilborne) between cattle and boophilus ticks. the model of babesia transmission was combined with a dynamic life history model for population dynamics of the tick vectors, boophilus microplus (canestrini) and b. annulatus (say). epidemiological parameters and relationships in the model include the reduction in fecundity of infected ti ... | 1992 | 1495038 |
| a specific dna probe which identifies babesia bovis in whole blood. | a genomic library of babesia bovis dna from the mexican strain m was constructed in plasmid pun121 and cloned in escherichia coli. several recombinants which hybridized strongly to radioactively labeled b. bovis genomic dna in an in situ screening were selected and further analyzed for those which specifically hybridized to b. bovis dna. it was found that pmu-b1 had the highest sensitivity, detecting 25 pg of purified b. bovis dna, and 300 parasites in 10 microliters of whole infected blood, or ... | 1992 | 1496779 |
| investigations of breakdowns in protection provided by living babesia bovis vaccine. | field investigations of protection afforded by live babesia bovis vaccine in australia revealed that a ninefold increase in vaccine failures occurred in the period from 1985 to 1990. laboratory trials using 189 experimental cattle were conducted to evaluate the protection afforded by the babesia bovis strain used in the commercial vaccine during this time. four isolates from clinical cases of babesiosis in vaccinated cattle were assessed. the results showed that the strain used in the vaccine du ... | 1992 | 1496802 |
| ribosomal dna sequence comparison of babesia and theileria. | previous studies on the taxonomy of babesia spp. (phylum apicomplexa) using morphological and life cycle characteristics have resulted in their classification into 3 subgenera, with the genus theileria being most closely related to them. using a strategy based on the direct sequence analysis of products derived by asymmetric pcr to determine the nucleotide sequences, we have tested the validity of this classification by sequencing the small subunit ribosomal rna genes amplified from 2 babesia sp ... | 1992 | 1518535 |
| lyophilised bovine serum as a substitute for frozen serum in the cultivation of babesia bigemina and b bovis. | lyophilised serum offers significant advantages over frozen serum when it comes to shipping such material over long distances. babesia bigemina and b bovis were cultured in medium supplemented by either frozen-thawed or lyophilised-rehydrated serum. there were no significant differences between the two types of medium in the growth of parasites and percentage of infected cells during subcultivation for 18 days. | 1992 | 1553430 |
| characterization of a cdna clone from the haemoparasite babesia bovis encoding a protein containing an "hmg-box". | the complete nucleotide sequence of a babesia bovis cdna clone encoding a protein containing an hmg-box has been determined. the predicted protein of 97 amino acids has a molecular weight of 11,116. it exhibits approximately 45% overall amino acid identity with the saccharomyces cerevisiae non-histone protein 6a (nhp6a) and approximately 57% identity in the hmg-box. the b. bovis protein has been designated nhp1. like hnp6a, and unlike most other hmg1 homologues, nhp1 does not have a basic or an ... | 1992 | 1567437 |
| mitochondrial function in babesia bovis. | a variety of anti-mitochondrial drugs that had previously been found to inhibit the growth of the malarial parasite plasmodium falciparum were tested on babesia bovis in vitro. several of these drugs were found to be non-toxic towards b. bovis. however, those drugs that were found to inhibit babesial growth included compounds (shown in parentheses) that have the following putative mitochondrial targets in the parasite: atp synthetase complex (rhodamine 123, oligomycin, janus green); atp-adp tran ... | 1992 | 1587679 |
| identification of l10e/l12e ribosomal protein genes in babesia bovis. | | 1992 | 1594456 |
| detection of babesia bovis carrier cattle by using polymerase chain reaction amplification of parasite dna. | carrier cattle infected with babesia bovis are difficult to detect because of the low numbers of parasites that occur in peripheral blood. however, diagnosis of low-level infections with the parasite is important for evaluating the efficacies of vaccines and in transmission and epidemiological studies. we used the polymerase chain reaction (pcr) to amplify a portion of the apocytochrome b gene from the parasite and tested the ability of this method to detect carrier cattle. the target sequence i ... | 1992 | 1624551 |
| chromosomes of babesia bovis and babesia bigemina. | | 1992 | 1625699 |
| immunization of cattle with an inactivated polyvalent vaccine against anaplasmosis and babesiosis. | | 1992 | 1626861 |
| rrna-based method for sensitive detection of babesia bigemina in bovine blood. | three synthetic oligonucleotide probes complementary to unique regions of babesia bigemina small-subunit rrna were developed for detecting the parasite in bovine blood. these probes specifically detected a parasitemia of 2 x 10(-5)% by autoradiography in less than 24 h by using a 200-microliters sample of bovine blood. these probes did not bind to total rna or genomic dna isolated from another closely related species, babesia bovis, or to bovine leukocyte rna. this method detected b. bigemina in ... | 1992 | 1629339 |
| bovine babesiosis: failure to induce interferon gamma production in response to babesia bovis antigens in cattle. | the immune response to babesia bovis infection or vaccination was evaluated by measuring antibody and interferon gamma (ifn-gamma) production to protective recombinant and crude native b. bovis antigens. cells from vaccinated or infected cattle failed to produce detectable ifn-gamma when stimulated with b. bovis antigens in vitro. in contrast, antibody was induced by protective recombinant b. bovis antigens. these findings are consistent with the argument that immunity to b. bovis infection is c ... | 1992 | 1639576 |
| babesia bovis: dextran sulphate as an adjuvant for and precipitant of protective immunogens. | dextran sulphate, a chemical with some specificity for lipoproteins, was used to precipitate a fraction from a soluble extract of babesia bovis-infected erythrocytes. the precipitate, in combination with dextran sulphate as an adjuvant, was used to vaccinate naive calves. the vaccinates and a group of control calves were challenged with virulent homologous b. bovis. the vaccinates showed delayed and decreased parasitaemias comparative to the controls. the antibody response to vaccination was pri ... | 1992 | 1644521 |
| babesia bovis: analysis of and preliminary vaccination studies with a defined infected erythrocyte membrane binding antigen. | murine monoclonal antibodies (mab) were produced against the 'beta' fraction of babesia bovis. a mab, w11c5, selected on the criterion of its staining of erythrocytes infected with b. bovis, was purified. the antigen identified by mab w11c5 was extracted from b. bovis infected erythrocytes by affinity chromatography and used in a vaccination trial to test its vaccine efficacy against homologous b. bovis infection in splenectomized calves. the vaccinated group showed significantly different paras ... | 1992 | 1644530 |
| purine salvage and metabolism in babesia bovis. | studies of the incorporation of radio-labelled purine precursors into the erythrocytic forms of babesia bovis under tissue-culture conditions have confirmed the presence in the parasite of enzymatic activities responsible for the salvage of preformed purines. the results also revealed that the parasite was capable of a variety of nucleotide interconversions, such that exogenous hypoxanthine and adenosine were incorporated into both adenine and guanine nucleotides followed by the incorporation of ... | 1990 | 1690419 |
| seroepidemiological studies of bovine babesiosis on pemba island, tanzania. | serological evidence of infection with babesia bovis and babesia bigemina at a number of sites in pemba was obtained using an enzyme-linked immunosorbent assay (elisa) capable of detecting the appropriate parasite-specific antibody. overall, 96% of animals were found to be positive for b. bovis, 88% were positive for b. bigemina and 88% were positive for both babesia species. antibody to b. bovis and b. bigemina was detected early in life in a number of calves born on pemba, and was considered t ... | 1990 | 1702568 |
| characterization of the gene encoding a 60-kilodalton babesia bovis merozoite protein with conserved and surface exposed epitopes. | a clone expressing a surface exposed, conserved epitope of a 60-kda merozoite polypeptide was identified in a cdna library constructed from a cloned mexico strain of babesia bovis. sequencing of the 1.9-kb insert (pbv60) revealed an open reading frame encoding a 65-kda polypeptide with a signal peptide and a tandemly repeated region. monoclonal antibody 23/56.156, which binds a surface exposed epitope on the native polypeptide, specifically immunoprecipitated [35s]methionine-labeled polypeptides ... | 1991 | 1712911 |
| strain variation of babesia bovis merozoite surface-exposed epitopes. | babesia bovis merozoites are exposed to antibodies during the extraerythrocytic phase, and surface polypeptides bearing exposed epitopes are possible immunogens. monoclonal antibodies reactive with the merozoite surface bind either immunodominant epitopes expressed diffusely on the merozoite surface or, alternatively, epitopes expressed in a polar pattern. epitopes expressed diffusely on the immunodominant 42- and 44-kda merozoite polypeptides were not conserved among strains from geographically ... | 1991 | 1715329 |
| induction of proliferative responses of t cells from babesia bovis-immune cattle with a recombinant 77-kilodalton merozoite protein (bb-1). | a major portion of a babesia bovis-specific gene encoding a 77-kda merozoite protein (bb-1) produced during natural infection in cattle and in microaerophilous culture was subcloned into the pgex1n expression vector. recombinant bb-1 protein fused to glutathione s-transferase (bb-1-gst) was used to examine cellular immune responses in b. bovis-immune cattle. sera from rabbits immunized with bb-1-gst reacted with fusion protein and with the native antigen present in crude b. bovis but not with b. ... | 1992 | 1730498 |
| babesia bovis host cell recognition proteins. | babesia bovis enters host erythrocytes by invagination but nothing is known of the proteins involved. by means of metabolic labelling, differential centrifugation in oil and salt elution, a number of babesial proteins have been shown to bind to bovine erythrocytes. strong binding is evidenced only by a 38/19 kda pair. preliminary experiments indicate that these two proteins also bind to human erythrocytes, although apparently to a lesser extent. | 1991 | 1743859 |
| goat serum, a substitute of bovine serum in cultivation of babesia bovis. | babesia bovis (a mexican isolate) was cultivated in masp culture system using goat serum in various concentrations as substitute of bovine serum. it was observed that 20% goat serum + 20% bovine serum + 60% parker's medium 199 supported the growth of the parasite, which was maintained in this medium through 8 subcultures. the soluble exoantigen (vaccine) present in the culture supernatant is to be quantified and tested in vitro. goat serum from slaughterhouses may be utilized for in vitro cultiv ... | 1991 | 1750362 |
| the toxicity of adenosine analogues against babesia bovis in vitro. | the toxicities of 20 analogues of deoxyadenosine or adenosine were tested in vitro against the intraerythrocytic parasite babesia bovis. ic37 values (the concentration of compound required to reduce cell survival to 37%) were determined for each compound. tubercidin (7-deaza-adenosine), 2-bromo-adenosine, 8-bromo-3-ribosyl adenine and 6-phenylamino-deoxyadenosine were shown to be the most toxic towards b. bovis. comparison of the toxicity results for these compounds in b. bovis with those in hum ... | 1991 | 1757207 |
| distribution of boophilus species ticks in swaziland. | recent outbreaks of bovine babesiosis caused by babesia bovis in swaziland had indicated the presence of the vector tick boophilus microplus in the country although it had never before been directly identified. engorged female boophilus ticks were collected from cattle at diptanks in the course of a tick resistance survey and used to map the distribution of the two different species of boophilus. b. decoloratus was found to be widespread throughout the country. b. microplus was identified for th ... | 1991 | 1763439 |
| sequence conservation among merozoite apical complex proteins of babesia bovis, babesia bigemina and other apicomplexa. | | 1991 | 1775174 |
| igm rheumatoid factor in cattle immunized against babesiosis. | polyclonal bovine igm-rheumatoid factors (igm-rfs) were examined in sera of cattle immunized against babesiosis. an enzyme-linked immunosorbent assay (elisa) was used enabling rapid screening of serum samples. results obtained indicate a rise of serum igm-rf levels with age in healthy bovines. however when animals of similar age and pertaining to the same herd were examined, levels of serum igm-rf exhibited a wide distribution range. mean values in 60 sera of 2 yrs old clinically healthy heifers ... | 1991 | 1776376 |
| development of an in vitro microtest to assess drug susceptibility of babesia bovis and babesia bigemina. | continuous cultivation of the bovine hemoparasites babesia bovis and babesia bigemina was developed as an in vitro microtest to assess parasite susceptibility to babesicidal compounds. reproducibility of parasite multiplication rates was independent of culture size, making it possible to use a microscale of 100 microliters for each test sample. inhibitory concentrations (ic50s) of a commonly used babesicide, quinuronium sulfate, evaluated by this in vitro method were found to be 5 x 10(-8) g/ml ... | 1991 | 1779305 |
| new nucleoside transport pathways induced in the host erythrocyte membrane of malaria and babesia infected cells. | | 1991 | 1789200 |
| preliminary observations on ticks and tick-borne diseases in the north west province of cameroon. i. babesiosis and anaplasmosis. | during a survey on ticks and tick-borne diseases in the north-western cameroon at the bamenda cattle market, the ticks identified were boophilus annulatus (20%) and b. decoloratus (80%). more than 50% of the ticks were collected during the dry season. of 524 blood smears 47.3% were positive for babesia bovis, 31.1% for b. bigemina and 2.2% for anaplasma marginale. 19.4% were negative. | 1991 | 1824132 |
| dna probes for the detection of babesia caballi. | a genomic library of babesia caballi dna was constructed in the plasmid vector puc13. the specificity of the clones for b. caballi was established by the lack of hybridization to babesia equi, babesia bovis, babesia bigemina and equine dna. two probes, pbc11 and pbc191, were isolated that could detect 0.25 ng and 0.125 ng of b. caballi dna, corresponding to a parasitaemia of 0.12% and 0.06% respectively. pbc191 could detect b. caballi parasites in the blood of an experimentally infected horse as ... | 1991 | 1866181 |
| an elisa for the diagnosis of babesia ovis infection utilizing a synthetic, babesia bovis-derived antigen. | the development of an enzyme-linked immunosorbent assay (elisa) for the detection of babesia ovis antibodies is described. in an initial study, a crude babesia bovis antigen and a synthetic b. bovis-derived antigen (designated 11c5) were used to screen 46 b. ovis-positive and 55 negative sheep sera. a 95% correlation between the two antigenic preparations was found with the positive sera; no negative sera gave positive reactions. the synthetic antigen was then used in the screening of 1466 sera ... | 1991 | 1957483 |
| cell-mediated immune responses to babesia bovis merozoite antigens in cattle following infection with tick-derived or cultured parasites. | peripheral blood mononuclear cells from cattle experimentally infected with babesia bovis were examined for parasite-specific cell-mediated immune responses. unfractionated merozoites and soluble and membrane fractions derived from merozoites were all antigenic for immune cattle, although the membrane fraction was the most stimulatory. cattle responded to different antigenic fractions in a differential manner, and only that animal immunized with autologous cultured parasites responded to parasit ... | 1991 | 2050406 |
| effect of diamide on nucleoside and glucose transport in plasmodium falciparum and babesia bovis infected erythrocytes. | normal human erythrocytes, preincubated with the oxidizing agent diamide, did not demonstrate any increased permeability, but showed a significant decrease in their ability to transport the nucleoside adenosine. diamide appeared to have little effect on glucose permeation in uninfected and plasmodium falciparum infected cells. the inhibition of adenosine transport in human erythrocytes by diamide pretreatment appeared to be unrelated to the inhibition by the established nucleoside transport inhi ... | 1991 | 2052021 |
| a putative rna virus in babesia bovis. | babesia bovis is an intraerythrocytic protozoan that causes bovine babesiosis. agarose gel electrophoresis of nucleic acids extracted from two isolates of b. bovis reveals, besides bulk dna, an ethidium bromide-stainable band at about 5.5 kb. further characterization of the latter with dnase i, rnase and mung bean nuclease suggested it to be a double-stranded rna. sonicated parasites were fractionated in a cscl buoyant density gradient. a sample containing the 5.5-kb rna was analysed under an el ... | 1991 | 2052034 |
| a flow cytometric method for assessing viability of intraerythrocytic hemoparasites. | we have developed a rapid, reliable method of evaluating growth and viability of intraerythrocytic protozoan hemoparasites. the assay involves the selective uptake and metabolic conversion of hydroethidine to ethidium by live parasites present in intact erythrocytes. the red fluorescence imparted by ethidium intercalated into the dna of the parasite permits the use of flow cytometry to distinguish infected erythrocytes with viable parasites from uninfected erythrocytes and erythrocytes containin ... | 1991 | 2061611 |
| calcium-dependent protein phosphorylation in babesia bovis and its role in growth regulation. | intracellular growth of protozoan parasite babesia bovis has been followed to study the effect of some chemical agents on growth regulation. using an in vitro parasite culture system we present evidence that the normal growth of the parasite is dependent upon available calcium and a ca2(+)-binding protein, calmodulin, because sequestration of either of these 2 components from the culture medium causes inhibition of parasitic growth. further studies demonstrate that the parasite contains a protei ... | 1990 | 2108234 |
| immunodiagnosis of and immunoprophylaxis against the haemoparasites babesia sp. and anaplasma sp. in domestic animals. | the haemoparasites babesia bovis and anaplasma marginale are extremely important pathogens of cattle, affecting more than 300 million animals worldwide. species of less importance affect cattle, dogs, horses and sheep. no vaccine is available for widespread usage. this review summarises existing immunodiagnostic and immunoprophylactic methods currently available for these diseases and reports on future immunoprophylactic methods. | 1990 | 2132684 |
| a slide enzyme-linked immunosorbent assay (selisa) for the diagnosis of babesia bovis infections and for the screening of babesia-specific monoclonal antibodies. | a slide enzyme-linked immunosorbent assay (selisa), a modification of the standard elisa technique, was developed for detection of babesia bovis antibodies in bovine sera. smears of b. bovis-infected blood were used as the source of antigen in the test which was read using a light microscope. monoclonal antibodies to defined b. bovis antigens were used to demonstrate the cellular specificity of the test. the selisa was shown to be as sensitive as existing non-enzyme based serological tests for b ... | 1990 | 2192988 |
| tick-borne diseases of cattle in paraguay. ii. immunisation against anaplasmosis and babesiosis. | a total of 102 susceptible adult holstein friesian cattle imported into an area of paraguay where anaplasmosis and babesiosis are endemic were immunised by infection with anaplasma centrale and attenuated forms of babesia bigemina and babesia bovis obtained from uruguay. the results indicated that the attenuated forms of both babesia species protected cattle against heterologous field challenge whereas a. centrale did not invariably confer sufficient protection against a field challenge of a. ma ... | 1990 | 2196724 |
| babesia bovis: immunity induced by vaccination with a lipid enriched fraction. | a chloroform extract from babesia bovis-infected erythrocytes was used to vaccinate a group of five naive cattle. following vaccination, the vaccinates, along with a group of control cattle, were challenged with a virulent heterologous strain of b. bovis. the vaccinates, comparative to the controls, showed delayed as well as decreased parasitaemias. the serological and initial biochemical studies suggested that the immune response was elicited by lipid of babesial origin. | 1990 | 2228430 |