TitleAbstractYear(sorted ascending)
preparation and laboratory testing of a frozen vaccine containing babesia bovis, babesia bigemina and anaplasma centrale.procedures used to prepare and test frozen vaccine against bovine tick fever are described. blood from splenectomised calves infected separately with babesia bovis, babesia bigemina and anaplasma centrale was diluted in the ratio of 3:1 with 8 m dimethyl sulphoxide in phosphate buffered saline and cooled at rates between 5 degrees c and 110 degrees c per minute to -196 degrees c. after varying periods of storage up to 369 days, blood was thawed by immersing containers in a 40 degrees c water bat ...19827079601
the effects of the piroplasm babesia bigemina on the survival and reproduction of the blue, tick, boophilus decoloratus. 19827086165
anaplasmosis and babesiosis in el salvador.a serological survey was carried out in the central american state of el salvador to determine the distribution and prevalence of anaplasma marginale, babesia bigemina and babesia bovis. the results suggest that the parasites are widely distributed throughout the country and prevalence rates of 78.5% for a. marginale, 70.5% for b. bigemina and 73.5% for b. bovis were obtained. tick counts suggest that boophilus microplus is the main blood parasite vector. epidemiological studies showed that init ...19827101466
some effects of time, temperature and feeding on infection rates with babesia bovis and babesia bigemina in boophilus microplus larvae. 19827118375
studies on the infectivity of boophilus decoloratus males and larvae infected with babesia bigemina. 19827122059
babesia bigemina vaccine: comparison of the efficacy and safety of australian and south african strains under experimental conditions in south africa.a babesia bigemina vaccine strain (g strain) of reduced virulence was obtained from australia and tested experimentally for efficacy and virulence. the strain caused mild reactions in 10 animals and afforded good protection to challenge with a virulent south african strain. the virulence of the local vaccine strain was not noticeably reduced after 3 slow passages in intact calves and it was consequently replaced by the australian strain in the onderstepoort babesiosis vaccine.19827177595
babesia, theileria and anaplasma spp. infecting sable antelope, hippotragus niger (harris, 1838), in southern africa.some observations are recorded on blood parasites of sable antelopes. blood smears of 124 of these antelopes from south africa and zimbabwe were examined and 7 were found to be positive for a babesia sp., identified as babesia irvinesmithi martinaglia 1936. a total of 70 of the smears were positive for theilerial piroplasms, while 1 smear had macroschizonts (with cytomeres) and microschizonts of a theileria (= cytauxzoon) sp. one blood smear was positive for an anaplasma sp. attempts to isolate ...19826817250
epidemiology of tick-borne diseases of cattle in zimbabwe. i. babesiosis.a survey on the incidence of antibodies to babesia bigemina and babesia bovis in one to three year old calves at 274 localities in zimbabwe revealed that b. bigemina occurred throughout the country together with its main vector, boophilus decoloratus. the distribution of b. bovis followed closely that of its vector boophilus microplus which is limited to the eastern part of the country. enzootic stability for b. bigemina was recorded in most of the communal tribal areas where regular dipping of ...19836868134
the effect of tick control on the epidemiology of bovine babesiosis.the effect of tick control on the infection rates of babesia bovis and babesia bigemina are reported for 6 geographical regions in south africa. under conditions of poor tick control the situation for b. bovis was one of apparent enzootic instability in the 2 regions where its presence was recorded. under similar conditions the situation for b. bigemina was generally stable. with good tick control b. bovis infection rates were reduced to very low levels, with minimal losses being recorded. in th ...19836877790
serological response of cattle to infection with babesia bigemina and babesia bovis in southern africa.the indirect fluorescent antibody test was used to measure the antibody response of cattle for 8 weeks after infection with either babesia bigemina or babesia bovis, or a combination of both species. serological cross-reactions were observed between the 2 species, but these were most marked when b. bigemina antigen was used. in animals infected with both babesia spp., the b. bigemina reaction appeared to suppress the b. bovis reaction.19836634084
the use of tick transmission by boophilus microplus to isolate pure strains of babesia bovis, babesia bigemina and anaplasma marginale from cattle with mixed infections.pure strains of babesia bovis, babesia bigemina and anaplasma marginale were isolated from cattle infected with all 3 species as well as theileria sp. and eperythrozoon teganodes, using only transmission by the tick, boophilus microplus. unengorged adult ticks transferred to susceptible cattle transmitted a. marginale, but not babesia. engorged adults gave rise to progeny that transmitted babesia, b. bovis by larvae and b. bigemina by male ticks. the theileria and e. teganodes were not transmitt ...19836686384
the enzymes of pyrimidine biosynthesis in babesia bovis and babesia bigemina.all six enzymes of de novo pyrimidine biosynthesis leading to the formation of ump have been demonstrated in whole homogenates from two bovine babesia species, b. bovis and b. bigemina. the specific activities of the respective enzymes were of the same order of magnitude as observed for the related parasite, plasmodium berghei. the results indicate that both these parasites have the potential of obtaining their pyrimidine requirements by de novo synthesis. subcellular fractionation established t ...19836309129
comparison of blood smear and indirect fluorescent antibody techniques in detection of haemoparasite infections in trade cattle in nigeria.the incidence of blood parasites in trade cattle was surveyed with emphasis on tick-borne parasites, using blood smears and immunofluorescent antibody (ifa) techniques. with the blood smear method, about 9 and 8.9% of cattle examined were found positive for babesia bigemina and anaplasma marginale, respectively. percentage infections with other parasites were 3.33, 1.92, 0.75, 0.75 and 0.58, respectively, for babesia bovis, trypanosoma brucei, anaplasma centrale, eperythrozoon and theileria spec ...19846369761
the effect of chemotherapy on babesia bigemina in the tick vector boophilus microplus. 19846469445
chemoprophylaxis with diminazene aceturate in experimental babesia bigemina infection in cattle.four-month-old fully susceptible cross bred calves were immunised against babesia bigemina infection by treating them, during the prepatent period, with one or two doses of diminazene aceturate at 3 mg (kg bodyweight)-1. after 45 days the recovered calves were challenged with the homologous strain of b bigemina infected blood. the ensuing host responses, body temperature, parasitaemia, haemoglobin, packed cell volume, haemoglobinuria, capillary agglutinating antibodies and mortality, were studie ...19846473911
enzyme and bilirubin reactions in bovine babesiosis.four white fulani calves were splenectomized and experimentally infected with babesia bigemina by allowing about 2000 freshly hatched infective larvae of boophilus decoloratus to feed on them. blood samples were collected to determine serum glutamate pyruvate transaminase, serum glutamate oxaloacetate transaminase, alkaline phosphatase and bilirubin levels. a significant rise in the level of alkaline phosphatase for up to two weeks was observed. there were also increases in the serum glutamate p ...19846517473
the protective effect of pretreatment with killed corynebacterium parvum against acute babesiosis in calves.yearling calves were pre-treated intravenously (iv) with a 0.20 mg kg-1 dose of corynebacterium parvum and challenged after 30 days by iv inoculation of 3 x 10(9) babesia bigemina. the relatively low 0.20 mg kg-1 dose of c. parvum enhanced resistance as indicated by lower mean babesia parasitemias and less severe decreases in packed-cell volumes than in non-treated calves, but failed to stimulate a significant (p less than or equal to 0.05) level of protection against b. bigemina challenge.19846541833
common and isolate-restricted antigens of anaplasma marginale detected with monoclonal antibodies.anaplasma marginale-infected erythrocytes were examined for the presence of maturation, isolate-restricted, and isolate-common antigens by indirect immunofluorescence with monoclonal antibodies. a panel of 18 monoclonal antibodies was used; none of the antibodies reacted with anaplasma ovis, babesia bigemina, babesia bovis, trypanosoma brucei, trypanosoma congolense, or uninfected bovine erythrocytes. antigens common to all six a. marginale isolates were detected by nine antibodies. single isola ...19846205996
the detection of igm and igg antibodies against babesia bigemina in bovine sera using semi-defined antigens in enzyme immunoassays.soluble extracts prepared from babesia bigemina merozoites were tested for antigenicity in class-specific enzyme immunoassays currently being evaluated for the differential serodiagnosis of bovine babesiosis. intact merozoites were harvested from erythrocytes from an experimentally-infected calf by controlled hypotonic lysis and differential ultra-centrifugation. the merozoites were disrupted by ultrasonication and a crude soluble extract obtained by ultracentrifugation. fractionation of the cru ...19852413610
the effect of babesia bigemina infections caused by cattle ticks on nigerian economy. 19853841960
in vitro cultivation of babesia bigemina.a strain of babesia bigemina was isolated from an infected calf and propagated in vitro. culture conditions included washing of infected and normal bovine erythrocytes in a special solution, and the use of a 5% to 10% (v/v) erythrocyte suspension in medium 199 (with 20% to 50% fresh normal bovine serum) at a depth of 4 mm in a 5% co2, 2% o2, 93% n2 atmosphere. after 36 days in vitro and 9 subcultures, the cultured organism was inoculated into a susceptible calf. this calf developed clinical sign ...19853888009
cryopreservation of babesia bigemina for in vitro cultivation.babesia bigemina-infected rbc and merozoites were cryopreserved and used to initiate in vitro cultures in normal bovine rbc; the cryoprotectant was a final 10% polyvinylpyrrolidone in vega y martinez solution. a cooling rate of 20 c/min until -80 c and then rapid transfer to liquid n2 storage was satisfactory. samples for culture initiation were rapidly thawed at 37 c, washed in vega y martinez solution and resuspended in complete culture media containing 10% normal bovine rbc. the optimum cultu ...19853922260
susceptibility of bos indicus and bos taurus to anaplasma marginale and babesia bigemina infections.the reaction of bos taurus and pure-bred bos indicus heifers to infection with the intraerythrocytic parasites anaplasma marginale and babesia bigemina was studied. b. bigemina infection at 18 months and a. marginale infection at 13 or 24 months resulted in slightly less severe reactions in pure-bred bos indicus cattle than in bos taurus. in both breeds, the reaction to a. marginale infection was more severe in older cattle. the severity of b. bigemina infection was not affected by a previous in ...19853992874
cross-reaction of tick salivary antigens in the boophilus microplus-cattle system.calves were immunized with boophilus microplus saliva, filtered through millipore membranes, in freund's complete adjuvant. serum samples were tested by passive hemagglutination against babesia bigemina, anaplasma marginale, b. microplus larvae extract, stomoxys calcitrans extract and b. microplus saliva. after immunization, titers to saliva, larval tick-extract and to s. calcitrans were increased. the challenge with live tick larvae enhanced the formation of antibodies against larva extract, fl ...19853992881
prevalence of anaplasma marginale, babesia bigemina and b. bovis in nigerian cattle using serological methods.serum samples collected randomly from 500 cattle from the 10 northern states of nigeria were tested for antibodies against anaplasma marginale by indirect fluorescent antibody (ifa), card agglutination (ct) and capillary tube-agglutination (ca) tests. the serum samples were also examined for antibodies to babesia bigemina and b. bovis by the ifa test only. of the serum samples tested, 79.4% had antibodies against a. marginale by the ifa test, 40 and 25% in the ct and ca tests, respectively. the ...19863538640
cloning of in vitro propagated babesia bigemina.the original babesia bigemina culture conditions were modified with regard to infected bovine erythrocyte concentration and atmospheric environment. a procedure was designed which would yield a homogeneous parasite population, beginning with a single infected erythrocyte. calculated dilutions were made in 96-well tissue culture plates to approach one infected erythrocyte per four wells. growth of parasites in wells was detected between 16 and 28 days after cultures were initiated. clones were tr ...19863564325
effect of different methods of maintenance on the development and morphology of babesia bigemina in the gut of boophilus microplus.the development and morphology of babesia bigemina in the gut of boophilus microplus ticks were studied during laboratory maintenance of the babesia by four methods: tick transmission in unsplenectomised (intact) calves; tick transmission in splenectomised calves; syringe passage at intervals of five days or less in splenectomised calves; and syringe passage at intervals of six weeks or more in intact calves. the first method had no apparent effect on the development of b bigemina in ticks compa ...19863704330
chemoprophylactic activity of imidocarb, diminazene and oxytetracycline against babesia bovis and b. bigemina.splenectomized calves treated with imidocarb, diminazene, and oxytetracycline were exposed to babesia bigemina and b. bovis stabilates at various time intervals following treatment to evaluate prophylactic efficacy. diminazene showed no residual activity against a b. bigemina challenge given 54 days after treatment. oxytetracycline appeared responsible for an increased incubation time when given 2 days prior to b. bigemina exposure. imidocarb showed marked prophylactic efficacy against both b. b ...19863739203
the inability of a south african babesia bovis vaccine strain to infect boophilus microplus.a strain of babesia bovis that had been attenuated by rapid syringe passage through a series of 23 splenectomized calves was unable to infect its vector boophilus microplus. an attempt to transmit the attenuated australian babesia bigemina g strain with a south african strain of b. microplus was likewise unsuccessful. the epidemiological implication of these observations in terms of babesiosis control is discussed.19863763166
concentration and enzyme content of in vitro-cultured babesia bigemina-infected erythrocytes.clones of in vitro-cultured babesia bigemina-infected erythrocytes were concentrated by several density gradient procedures. the density range of infected erythrocytes containing pairs of parasites was 1.077 to 1.089 g/ml, whereas the density range of infected erythrocytes containing single parasites was 1.092 to 1.100 g/ml. three enzymes--lactate dehydrogenase, glucose-phosphate isomerase, and glutamate dehydrogenase--were found associated with infected erythrocytes. the parasite-specific enzym ...19863795142
detection of babesia bovis using dna hybridization.plasmids containing inserts of babesia bovis dna were prepared and clones suitable for use in the diagnosis of b. bovis infections were isolated. dot blot hybridization with dna from these plasmids, which probably contain repetitive sequences, can detect after an overnight exposure 100 pg of b. bovis dna, which corresponds to the amount of dna present in 50 microliters of 0.01% parasitemic erythrocytes. no detectable cross-hybridization was observed with babesia microti, plasmodium falciparum, p ...19863007751
chronic splenitis as a possible complicating factor in calves inoculated with an attenuated redwater two consecutive years a total of 3810 calves were inoculated with the onderstepoort redwater live-blood vaccine, containing attenuated strains of babesia bigemina and babesia bovis. twenty calves died 8-13 days later due to b. bigemina-infection. necropsies were performed on 19 of these animals. in 11 calves the spleen was distinctly smaller than normal and its morphology was distorted, and showed changes of chronic splenitis. histological lesions in the spleens of 6 of the 11 calves are desc ...19873508205
monoclonal antibodies that distinguish trypanosoma congolense, t. vivax and t. brucei.monoclonal antibodies (moabs) were derived against in-vitro-propagated procyclic forms of trypanosoma congolense, t. vivax, t. brucei brucei and t.b. rhodesiense in order to identify antigens for use in immunodiagnosis of african trypanosomiasis. the antibodies have been tested against procyclic and bloodstream form trypanosomes of 13 t. congolense, six t. vivax six t.b. brucei, four t.b. rhodesiense, five t.b. gambiense and three t. simiae isolates from different geographical areas by indirect ...19873306569
detection of culture-derived babesia bovis exoantigen using a two-site enzyme immunoassay.soluble exoantigens in the supernatants of babesia bovis cultures have been shown to be efficient immunogens against bovine babesiosis. we used a two-site enzyme immunoassay to monitor the release of these antigens during in vitro cultivation. bovine immunoglobulin g was isolated from serum of an adult cow previously immunized with culture-derived b. bovis exoantigens and challenged via needle with virulent parasites. the specific immunoglobulin g was used as a capture antibody and as an enzyme- ...19873308949
bovine babesiosis: induction of protective immunity with culture-derived babesia bovis and babesia bigemina immunogens.the comparative protective efficacy of culture-derived babesia bovis and b. bigemina immunogens against challenge exposure of susceptible crossbred cattle to heterologous strains was examined and correlated with the antigenic threshold requirements for induction of protective immunity. strong protection was observed in animals vaccinated with 10 ml-equivalent doses of soluble, b. bovis exoantigen-containing supernatant fluids. similar protective responses to b. bigemina exoantigens were evident ...19873325981
antibodies define multiple proteins with epitopes exposed on the surface of live babesia bigemina merozoites.babesia bigemina is one of several tick-borne hemoparasitic diseases of cattle that are inadequately controlled and cause substantial livestock production losses in tropical and subtropical climates. recovery from acute babesiosis is associated with development of protective immunity against subsequent challenge with both homologous and heterologous parasites. viable and infectious merozoites, the intraerythrocytic stage of b. bigemina responsible for clinical disease, were separated from contam ...19872435796
experimental infections of babesia bigemina in american bison.babesia bigemina was experimentally transmitted from cattle to bison and back to cattle. one spleen-intact and two splenectomized american bison (bison bison) inoculated with a b. bigemina stabilate exhibited clinical and hematological signs of babesiosis within 10 days of exposure. blood from the infected bison produced disease in a splenectomized bovine steer.19873820431
effect of infection by babesia spp. on the development and survival of free-living stages of boophilus annulatus.oviposition, egg hatching and survival of newly-hatched larvae of boophilus annulatus were studied in relation to infection by babesia species and different temperature regimens. infection of female ticks by babesia bigemina or b. bovis had no effect on the time elapsed between engorgement and oviposition. the duration of oviposition was shorter in infected females incubated at 25 degrees c or 35 degrees c and infected females laid fewer eggs than the controls. no larvae hatched at 16 degrees c. ...19873564342
protection of babesia bigemina-immune animals against subsequent challenge with virulent babesia bovis.two groups of cattle, one previously exposed to babesia bigemina and one not, were challenged with babesia bovis. the group previously infected with babesia bigemina was only mildly affected upon challenge with b. bovis, whereas four of five of the other group were severely affected. immunoblotting studies performed in both homologous and heterologous systems showed that there were polypeptides of similar molecular weight in both species, but species-specific polypeptides were demonstrated only ...19873542832
identification of babesia bigemina and babesia bovis merozoite proteins with isolate- and species-common epitopes recognized by antibodies in bovine immune sera.immunoprecipitation of radiolabeled antigens with bovine antisera indicated that many babesia bigemina and babesia bovis merozoite proteins contain isolate-common epitopes, while at least 16 b. bigemina and 8 b. bovis proteins contain species-cross-reactive epitopes. one immunogenic, isolate-common, and species-specific candidate diagnostic protein from each species was identified.19882453470
effect of temperature on transovarial transmission of babesia bigemina (smith and kilborne, 1893) in boophilus annulatus (say, 1821).the effect of the temperature on the transovarial passage of babesia bigemina has been studied in female boophilus annulatus during their oviposition. kinetes of babesia were present in eggs laid at the temperatures of 16, 20, 26, 28, 30 and 35 degrees c. the rate of infection was temperature dependent. it reached at least 50%, even at low temperatures. the average infection level at 26 and 30 degrees c was 270 kinetes per egg. however, between 20 and 35 degrees c the eggs laid during the first ...19883347984
ticks parasitising the indian buffalo (bubalus bubalis) and their possible role in disease transmission.a total of 13 ixodid tick species, boophilus microplus, haemaphysalis bispinosa, haemaphysalis cornupunctata, haemaphysalis himalaya, heamaphysalis montgomeryi, hyalomma anatolicum anatolicum, hyalomma dromedarii, hyalomma marginatum isaaci, hyalomma (hyalommina) brevipunctata, hyalomma (hyalommina) hussaini, nosomma monstrosum, rhipicephalus haemaphysaloides, and r. turanicus were collected off 424 buffaloes from the northwestern states of india. ten tick species, amblyomma testudinarium, b. mi ...19883369083
the infection of various tick species with babesia bigemina, its transmission and identification.strains of boophilus decoloratus and b. microplus were easily infected with a single stock of babesia bigemina; boophilus annulatus could be infected less easily, and it was difficult to infect rhipicephalus evertsi. two strains of r. appendiculatus and one strain each of r. bursa and hyalomma anatolicum excavatum were refractory. the same stock of b. bigemina was transmitted by nymphs and adults of b. decoloratus but only by nymphs of r. evertsi. vertical infection was not observed in r. everts ...19883387405
epidemiology of bovine babesiosis and anaplasmosis in zambia.the serological prevalence of bovine babesiosis and anaplasmosis in the traditional farming sector of six provinces of zambia was determined using the indirect fluorescent antibody test (ifat) for babesiosis and the card agglutination test (cat) for anaplasmosis. antibodies to babesia bigemina occurred throughout the country whereas the prevalence of b. bovis followed the distribution of its tick vector boophilus microplus which is limited to the north-eastern part of the country. low numbers of ...19883070875
enzyme-linked immunosorbent assay using solubilised antigen for detection of antibodies to anaplasma enzyme-linked immunosorbent assay (elisa) was used to detect antibodies against anaplasma marginale. a marginale bodies were separated from parasitised erythrocytes by a modified nitrogen decompression method, sonicated, then solubilised with triton x-100 and used as the elisa antigen. in this elisa system the required amount of antigen protein was 16.2 ng for each well. in the course of experimental infections, of calves, significant antibody levels were detected by elisa and the complement ...19883238774
prevalence of anaplasmosis and babesiosis in n'dama cattle of the gambia.sera from 184 n'dama cattle randomly selected and averaging 2-7 years of age were tested for the presence of specific antibodies to anaplasma marginale, babesia bovis and b. bigemina, using one or more serological tests including complement fixation, rapid card agglutination and indirect fluorescent antibody (ifa). tests for a. marginale and b. bovis were essentially negative. utilising the ifa test 65% of the sera tested were positive for b. bigemina. three randomly selected two-year-old n'dama ...19883281338
concentration of babesia bigemina-infected erythrocytes using a dextran sulphate affinity column.babesia bigemina-infected erythrocytes preferentially bind to dextran sulphate affinity columns. subsequent elution yields suspensions containing up to 95% infected erythrocytes. preliminary immunoblotting studies indicate a parasite antigen of 35,000 mol. wt might be implicated in the binding.19892483954
[ticks and hemoparasitoses of livestock in senegal. iii. the northern sudan area].the authors describe the results of a study on ticks and hemoparasitoses of cattle and small ruminants in the senegalese north-sudanian area. for 15 months, 40 bovine, 40 sheep and 40 goats received a routine dipping treatment, aimed at the determination of the tick population dynamics together with an accurate localization of the preferential sites for the different species. the following parasites were collected from the animals: hyalomma marginatum rufipes, h. truncatum, rhipicephalus lunulat ...19892485548
comparison of immunogenicity and virulence between babesia bigemina parasites from continuous culture and from a splenectomised calf. 19892619652
bovine babesia bigemina seroreactors in jamaica. 19892694549
effect of different methods of maintenance on the pathogenicity and infectivity of babesia bigemina for the vector boophilus microplus.observations were made on the effects of five different methods of laboratory maintenance on the infectivity and virulence of babesia bigemina for the tick boophilus microplus. the original isolate was highly infective and virulent, causing premature death of engorged female ticks and reduced egg production. maintenance of the strain by syringe passage in unsplenectomised calves at six to 10 week intervals reduced both its infectivity and virulence for ticks. when slow passages were preceded by ...19892704879
repetitive dna probes for the detection of babesia equi.this report describes dna probes for the identification of babesia equi. a genomic library of b. equi was constructed in puc13. several clones were identified that hybridized strongly to b. equi dna. clone pbe33 hybridized specifically to b. equi dna and did not hybridize to horse dna nor to dna from babesia caballi, babesia bovis or babesia bigemina. two subclones of pbe33 (psb20 and peh21) containing b. equi repetitive sequences, could detect 0.49 ng and 0.97 ng b. equi dna, respectively.19892710167
development of a prophylactic regime using long-acting tetracycline for the control of redwater and heartwater in susceptible cattle moved into an endemic area.thirty young crossbred steers were purchased from a tick-borne disease-free farm in south africa, shown to be serologically negative to babesia bigemina/bovis and cowdria ruminantium, and moved to an experimental farm where babesiosis and heartwater were known to be endemic. the animals were allowed to graze as a herd on tick-infested areas of the farm for 90 days from the beginning of april but were separated into three groups of 10 for treatment. one group received a prophylactic regime of two ...19892711456
detection of babesia bigemina in cattle by a radioimmunoassay incorporating specifically depleted was observed that mild acidification (ph less than 4.0) together with solvent extraction of the soluble sonicate of a crude preparation of babesia bigemina infected cattle erythrocytes caused a quantitative loss of b. bigemina-specific antigen. cross-reacting antigen activities with babesia bovis remained intact. these properties were utilized in an assay system wherein antibody response to the specifically depleted antigen preparation was subtracted from the response to the initial crude pre ...19892763443
infectivity of cryopreserved babesia bovis, babesia bigemina and anaplasma centrale for cattle after thawing, dilution and incubation at 30 degrees c.blood containing either babesia bovis, babesia bigemina or anaplasma centrale was mixed with an equal volume of 3 m glycerol in phosphate-buffered saline with or without glucose and then stored in liquid nitrogen for 2-30 days. after being thawed, the parasitized blood was subjected to various procedures, including dilution up to 1000-fold followed by incubation at 30 or 4 degrees c for 8 h, before infectivity of the parasites was tested in a total of 70 cattle. the results showed that the blood ...19892763444
immunization of cattle against theileria parva bovis and their exposure to natural challenge.theileria parva bovis isolates were tested for their immunizing capacity under natural field challenge on willsbridge farm in the highveld of zimbabwe. fifteen susceptible sussex yearlings were immunized with the boleni stock and 15 with a mixture of three isolates from the farm, using tick-derived sporozoite stabilates. no chemoprophylaxis was used. a dose of 0.1 ml of stabilate appeared to be safe in preliminary laboratory experiments, but the reactions were severe in the sussex cattle and one ...19902125158
tick-borne diseases of cattle in paraguay. ii. immunisation against anaplasmosis and babesiosis.a total of 102 susceptible adult holstein friesian cattle imported into an area of paraguay where anaplasmosis and babesiosis are endemic were immunised by infection with anaplasma centrale and attenuated forms of babesia bigemina and babesia bovis obtained from uruguay. the results indicated that the attenuated forms of both babesia species protected cattle against heterologous field challenge whereas a. centrale did not invariably confer sufficient protection against a field challenge of a. ma ...19902196724
[ticks and hemoparasitic diseases in cattle in senegal. iv. the southern sudan area].the authors report on the results of an investigation on ticks and hemoparasitoses of cattle, sheep and goats in the south sudanian area of senegal. systematic routine dipping against ticks of cattle, 40 sheep and 40 goats was set during 15 months, with a view to determine the population dynamics together with an acurate localization of the different species concerned. the following parasites were collected from these ruminants: amblyomma variegatum, boophilus geigyi, hyalomma truncatum, h. m. r ...19902218038
bovine borreliosis: comparison of simple methods for detection of the spirochaete in the blood.natural borrelia infection occurring in a calf was followed up using stained blood and buffy coat smears and direct observation of blood and buffy coat in order to compare these spirochaete detection methods. direct examination of the platelet-plasma interface of the microhaematocrit capillary tubes after centrifugation allowed detection of two parasitaemias that were not seen in giemsa stained blood smears. an ascending babesia bigemina infection seemed to suppress the borrelia parasitaemia. sp ...19902219454
purification of the erythrocytic stages of babesia bigemina from cultures.exposure of erythrocytes infected with babesia bigemina to glycerol-enhanced osmotic shock yielded preparations containing infected erythrocyte ghosts, free parasites, and some intact erythrocytes. the released parasites were purified and concentrated by centrifugation in percoll gradient. recovered free parasites were shown by the fluorescein acetate technique to be metabolically active, but their infectivity in vitro was low. it was demonstrated by electron microscopy that most of the released ...19902251242
dna probes distinguish geographical isolates and identify a novel dna molecule of babesia bovis.a genomic dna library of babesia bovis was screened to identify dna probe candidates for direct detection of the parasite. two sequences, bo6 and bo25, had the highest sensitivity and further analysis revealed unique characteristics of each of these. neither sequence hybridized detectably to bovine dna. bo6 detected 100 pg of both a mexican and an australian isolate of b. bovis, but bo6 also detected 1.0 ng of babesia bigemina dna under identical conditions. a unique characteristic of bo6 is tha ...19902254817
development of a recombinant anaplasma marginale dna anaplasma marginale dna probe has been developed by using an improved method for the isolation of genomic dna. purified genomic a. marginale dna from the st. croix isolate was partially digested with sau 3a1 into fragments (greater than or equal to 5.0 kb). the restriction fragments were cloned using standard techniques in the pbr322 vector and used to transform e. coli (dh5) host cells. the recombinant a. marginale dna library was screened by the colony lifting procedure. colonies containing ...19902260276
post-thawing viability of vaccines for bovine babesiosis and anaplasmosis cryopreserved with frozen vaccines containing babesia bovis, babesia bigemina or anaplasma centrale were prepared using glycerol as cryoprotectant and stored in liquid nitrogen. the viability of the vaccines was tested inoculating calves 1 h (n = 12), 2 h (n = 12), 12 h (n = 6) and 24 h (n = 6) after thawing. babesia bovis and a. centrale were detected in thin and/or thick blood smears in all vaccinated calves; however, 1 of 12 calves inoculated 1 h after thawing and 3 of 6 calves inoculated 24 h after thawin ...19902267730
in vitro adherence of erythrocytes infected with babesia bigemina and babesia rodhaini to thrombospondin.the adherence of erythrocytes infected with babesia bigemina and babesia rodhaini to thrombospondin (tsp) in vitro is demonstrated. blood with a range of parasitaemias was used and counts of cells which bound to tsp on plastic were significantly different from the controls with both babesia species. these studies indicated that tsp receptors are present on the surface of red blood cells infected with the two babesia species, although these parasites do not alter the membranes of infected erythro ...19902276864
tick-borne diseases of cattle in paraguay. i. seroepidemiological studies on anaplasmosis and babesiosis.a serological survey was carried out in paraguay to determine the prevalence of antibodies to anaplasma marginale, babesia bigemina and babesia bovis. the results suggest that the parasites are widely distributed throughout the country with prevalence rates of 92% for a. marginale, 79% for b. bigemina and 71% for b. bovis. epidemiological studies on calves demonstrated that initial infection with the three blood parasites occurs in most animals within the first nine months of life. it is likely ...19902321261
characterization of a repetitive dna probe for babesia bigemina.a plasmid (p16) containing a babesia bigemina dna insert was selected and labeled with 32p. this probe was evaluated for specificity and sensitivity by dot blot hybridization. the probe was specific and hybridized with only babesia bigemina dna, and not dna from babesia bovis, bovine leukocyte, trypanosoma brucei or anaplasma marginale. the dna probe detected as little as 10 pg of babesia bigemina dna. the probe hybridized with babesia bigemina isolates from mexico, the caribbean region and keny ...19902382379
identification of common surface antigens among babesia bigemina isolates by using monoclonal antibodies.a group of monoclonal antibodies (mab) was used to immunochemically characterize babesia bigemina surface components. two surface reactive mab by an ifat test were subsequently shown to bind to epitopes on the external surface of the parasite plasma membrane as evidenced by immunoelectron microscopy. parasite components with relative sizes of 68, 62, 60, 58, 56, 54, 51, 49, 48, 47, 43, 36 kda were identified with the group of mab in at least 6 geographically different b. bigemina isolates. the a ...19901693187
identification of a theileria mutans-specific antigen for use in an antibody and antigen detection elisa.purified piroplasms of theileria mutans were used to immunize balb/c mice to generate monoclonal antibodies (moabs). the moabs recognized an antigen of a relative molecular mass of 32 kda in western blots. this antigen was also recognized by sera from cattle which had recovered naturally from experimental tick-transmission or infections induced by the blood stages of t. mutans. the moabs did not react, in indirect immunofluorescence or enzyme-linked immunosorbent assays (elisa), with the common ...19901698274
seroepidemiological studies of bovine babesiosis on pemba island, tanzania.serological evidence of infection with babesia bovis and babesia bigemina at a number of sites in pemba was obtained using an enzyme-linked immunosorbent assay (elisa) capable of detecting the appropriate parasite-specific antibody. overall, 96% of animals were found to be positive for b. bovis, 88% were positive for b. bigemina and 88% were positive for both babesia species. antibody to b. bovis and b. bigemina was detected early in life in a number of calves born on pemba, and was considered t ...19901702568
characterization of the gene encoding a 60-kilodalton babesia bovis merozoite protein with conserved and surface exposed epitopes.a clone expressing a surface exposed, conserved epitope of a 60-kda merozoite polypeptide was identified in a cdna library constructed from a cloned mexico strain of babesia bovis. sequencing of the 1.9-kb insert (pbv60) revealed an open reading frame encoding a 65-kda polypeptide with a signal peptide and a tandemly repeated region. monoclonal antibody 23/56.156, which binds a surface exposed epitope on the native polypeptide, specifically immunoprecipitated [35s]methionine-labeled polypeptides ...19911712911
sequence conservation among merozoite apical complex proteins of babesia bovis, babesia bigemina and other apicomplexa. 19911775174
development of an in vitro microtest to assess drug susceptibility of babesia bovis and babesia bigemina.continuous cultivation of the bovine hemoparasites babesia bovis and babesia bigemina was developed as an in vitro microtest to assess parasite susceptibility to babesicidal compounds. reproducibility of parasite multiplication rates was independent of culture size, making it possible to use a microscale of 100 microliters for each test sample. inhibitory concentrations (ic50s) of a commonly used babesicide, quinuronium sulfate, evaluated by this in vitro method were found to be 5 x 10(-8) g/ml ...19911779305
sequence microheterogeneity of the three small subunit ribosomal rna genes of babesia bigemina: expression in erythrocyte culture.three distinct ribosomal rna (rrna) transcription units (rdna units), designated a, b and c, were identified in the intraerythrocytic protozoan parasite, babesia bigemina. these rdna units were cloned, and restriction maps were constructed showing the approximate location of the small and large rrna coding regions. the arrangement of the genes in the genome and copy number analysis suggests the presence of a single copy of each rdna unit per haploid genome. the complete nucleotide sequence of th ...19911840661
dna probes for the detection of babesia caballi.a genomic library of babesia caballi dna was constructed in the plasmid vector puc13. the specificity of the clones for b. caballi was established by the lack of hybridization to babesia equi, babesia bovis, babesia bigemina and equine dna. two probes, pbc11 and pbc191, were isolated that could detect 0.25 ng and 0.125 ng of b. caballi dna, corresponding to a parasitaemia of 0.12% and 0.06% respectively. pbc191 could detect b. caballi parasites in the blood of an experimentally infected horse as ...19911866181
immunogenicity and sequence analysis of recombinant p58: a neutralization-sensitive, antigenically conserved babesia bigemina merozoite surface protein.the gene encoding the conserved, neutralization-sensitive surface protein p58 of babesia bigemina was cloned and sequenced. an open reading frame of 1440 bases was found to encode a protein with a predicted size of 54 kda. a transmembrane hydrophobic domain and signal peptide were present at the amino-terminus. the polypeptide encoded by a nearly full length cdna was expressed in bacteria and contained epitope(s) reactive with anti-p58 polyclonal and monoclonal antibodies. serum antibodies from ...19911944417
molecular characterization and immunogenicity of neutralization-sensitive babesia bigemina merozoite surface proteins.monoclonal antibodies binding to the surface of live mexico isolate babesia bigemina merozoites have defined 4 parasite-encoded surface antigens (36, 45, 55, and 58 kda) that are potential targets for immune-mediated neutralization of merozoites. in this study, we have characterized the post-translational modification, antigenic polymorphism, and immunogenicity of these 4 proteins. monoclonal antibody immunoaffinity-purified 36- and 55-kda polypeptides were identical in gel electrophoresis to im ...19911944418
cell-mediated immune responses to babesia bovis merozoite antigens in cattle following infection with tick-derived or cultured parasites.peripheral blood mononuclear cells from cattle experimentally infected with babesia bovis were examined for parasite-specific cell-mediated immune responses. unfractionated merozoites and soluble and membrane fractions derived from merozoites were all antigenic for immune cattle, although the membrane fraction was the most stimulatory. cattle responded to different antigenic fractions in a differential manner, and only that animal immunized with autologous cultured parasites responded to parasit ...19912050406
in vitro inhibition of multiplication of babesia bigemina by using monoclonal antibodies.a panel of 21 monoclonal antibodies (mab) against the erythrocytic stages of babesia bigemina was produced. the 21 mab could be divided into four distinct immunofluorescence groups on the basis of their patterns of binding to b. bigemina-infected erythrocytes. nine mab positive in the indirect immunofluorescent antibody test with acetone-fixed b. bigemina-infected erythrocytes were selected for purification and further characterization. the mab were species specific, since they did not cross-rea ...19912056067
indigenous and crossbred cattle--a comparison of resistance to ticks and implications for their strategic control in zimbabwe.a comparison of the tick resistance of indigenous mashona and crossbred afrikander x sussex oxen following natural tick infestation indicated that significantly more african blue ticks boophilus decoloratus were found on the crossbred than the indigenous cattle (p < 0.05). the two groups of cattle were exposed to babesia bigemina and theileria taurotragi as indicated by high antibody titres on the indirect fluorescent antibody test, but no antibodies could be demonstrated to anaplasma marginale ...19921305338
impact of babesia bovis and babesia bigemina on the production of beef cattle in uruguay.uruguay is situated in a marginal area for the development of boophilus microplus (30 degrees 35 degrees south lat.) with important areas of enzootic instability for babesia bovis and b. bigemina. the livestock products represent 70% of our exports, for which reason it is fundamental to evaluate the losses in the production that these haemoparasites cause as basic information to take future decisions. in the period 1988-1990, several works were carried out by our laboratory to know the incidence ...19921343684
new methods for the diagnosis of babesia bigemina infection.accurate diagnosis of babesia bigemina infection, an economically important tick-transmitted protozoan parasite of cattle, is essential in the management of disease control and in epidemiological studies. the currently used methods of diagnosis are blood smear examination and serological tests which include agglutination and immunofluorescence tests. these tests have been used in the fild but because they lack sensitivity and specificity, newer and improved methods of diagnosis are being develop ...19921343691
detection of babesia bigemina infection: use of a dna probe--a review.the development of a repetitive dna probe for babesia bigemina was reviewed. the original plasmid (p(bbi)16) contained an insert of b. bigemina dna of approximately 6.3 kb. this probe has been evaluated for specificity and analytical sensitivity by dot blot hybridization with isolates from mexico, the caribbean region and kenya. a partial restriction map has been constructed and insert fragments have been subcloned and utilized as specific dna probes. a comparison of 32p labelled and non-radioac ...19921343692
evaluation of a colorimetric babesia bigemina-dna probe within an epidemiological epidemiological survey was conducted in southeast mexico, in an effort to establish the serological reactivity and carrier status to babesia bigemina of an indigenous cattle population. the prevalence was obtained through the indirect fluorescent antibody test (ifat), using an in vitro culture-derived b. bigemina antigen. a specific, digoxigenin-coupled, approximately 6 kb b. bigemina-dna probe (bbdp), was used to indicate the presence of the parasite. serum samples from 925 animals of all ag ...19921343694
antibody response to babesia bigemina infection in calves measured by elisa and immunoblotting measure the antibody response to babesia bigemina with an elisa test, three groups of cattle were experimentally infected with two isolates of the parasite. it was possible to demonstrate specific antibody binding directed against the parasite as early as the 7 days postinfection (pi). the highest level of antibody was obtained around day 1 to 23 and remained detectable for 260 days. challenge of the animals 260 days pi with a tick-induced b. bigemina infection depicted that homologous strain ...19921345116
babesia bovis: bovine helper t cell lines reactive with soluble and membrane antigens of merozoites.babesia bovis-specific t cell lines were established from cattle infected with either tick-derived or cultured parasites by stimulation of peripheral blood mononuclear cells with a crude parasite membrane fraction. induction and enrichment of cd4+ t cells occurred over time. all cell lines responded vigorously and in a dose-dependent, mhc-restricted manner to intact merozoites, and to soluble and membrane fractions derived from merozoites by homogenization and high-speed centrifugation. solubili ...19921371257
screening of a babesia bigemina cdna library with monoclonal antibodies directed to surface antigens.a babesia bigemina cdna library prepared in lambda zap bacteriophage vector was immunoscreened to detect clones expressing surface-exposed epitopes of b. bigemina. a nonradioactive indirect plaque-lift immunoassay was used to detect the positive clones. the primary antibody consisted of a pooled sample of six monoclonal antibodies (mab) specific for b. bigemina that recognizes various parasite surface antigens of different molecular mass. screening of approximately 300,000 plaque-forming units f ...19921378255
bovine helper t cell clones recognize five distinct epitopes on babesia bovis merozoite antigens.helper t cell clones from two babesia bovis-immune cattle were characterized for use in identification of potentially protective immunogens of b. bovis merozoites. proliferation assays with 11 cd4+ clones revealed a differential pattern of response to soluble cytosolic antigen, membrane-enriched antigen, detergent extracts of the membrane-enriched antigen, soluble culture supernatant exoantigen, and different geographical isolates of b. bovis as well as babesia bigemina parasites. when the data ...19921383149
serological and immunological studies with a hexane extract of babesia bovis-infected erythrocytes.antigenic and immunogenic activities of a hexane extract from babesia bovis-infected erythrocytes were investigated. positive elisa and ifat reactions were obtained with bovine antisera to b. bovis and b. bigemina produced by natural infection and rabbit antisera to the hexane extract, respectively. in contrast, negative elisa reactions were obtained with anaplasma marginale antisera indicating that the antigen(s) is specific for the genus babesia. the ifat clearly demonstrated that the antigen ...19921383165
vaccination of cattle with dextran sulphate-binding babesia bigemina antigens.dextran sulphate-bound babesia bigemina antigens were used in a preliminary vaccination study and were shown to elicit a protective immune response in cattle. a dextran sulphate-binding fraction of b. bigemina was further subfractionated on a phenyl sepharose column to give two fractions--one that strongly bound to the column (bound fraction) and one that did not (unbound fraction). two groups of cattle were each vaccinated with either the bound or the unbound fraction. these two groups of anima ...19921399246
detection of babesia bigemina-infected carriers by polymerase chain reaction amplification.a spei-avai fragment (0.3 kbp) from pbbi16 (a pbr322 derivative containing a 6.3-kbp babesia bigemina dna insert) was subcloned into the pbluescript phagemid vector and was sequenced by the dideoxy-mediated chain termination method. two sets of primers were designed for the polymerase chain reaction (pcr) assay. primer set ia-ib was used to amplify a 278-bp dna fragment, and primer set ian-ibn was used to prepare a probe directed to a site within the pcr-amplified target dna. digoxigenin-dutp wa ...19921400956
the effect of neutrophils, tumor necrosis factor, and granulocyte macrophage/colony stimulating factor on babesia bovis and babesia bigemina in culture.bovine neutrophils, human recombinant tumor necrosis factor-alpha (tnf), and bovine recombinant granulocyte macrophage/colony stimulating factor (gm/csf) were added to microaerophilic cultures of babesia bovis and babesia bigemina to determine if those substances could inhibit growth. incorporation of [3h]hypoxanthine by the babesia spp. was utilized as an indirect measure of parasite growth. when neutrophils were added to cultures of b. bovis and b. bigemina, the highest percentage inhibition o ...19921413450
babesia bovis, babesia bigemina, babesia canis, babesia microti and babesia rodhaini: comparison of ribosomal rna gene organization.the three ribosomal dna (rdna) units have been cloned from an australian isolate of babesia bigemina. the organization of the units is very similar to that reported for a mexican isolate of b. bigemina. in babesia canis four rdna units have been identified. both babesia rodhaini and babesia microti contain two different rdna units. a small number of different rdna units appears to be a common feature of this group of protozoa. restriction enzyme analysis of the rdna units form these species and ...19921428519
cloning and characterisation of members of a family of babesia bigemina antigen genes containing repeated sequences.bovine polyclonal antisera to babesia bigemina antigens separated by phenyl-sepharose chromatography were used to screen a b. bigemina lambda gt11 cdna expression library. eleven b. bigemina-specific cdna clones were studied in detail. dna sequencing of 2 representative clones identified open reading frames encoding polypeptides representing the carboxy-termini of 2 different proteins. both polypeptides contained a related central motif of tandem repeats flanked by a highly conserved carboxy-ter ...19921435874
development and persistence of cowdria ruminantium specific antibodies following experimental infection of cattle, as detected by the indirect fluorescent antibody test.different breeds of cattle were experimentally infected with palm river, a zimbabwean isolate, or ball-3, a south african isolate of cowdria ruminantium, derived from tissue culture or tick or blood stabilates. c. ruminantium specific antibody responses were detected by an indirect fluorescent antibody test (ifat) using c. ruminantium-infected bovine aortic endothelial (bae) cell cultures as antigen. the first detection of antibodies to c. ruminantium generally coincided with the peak of the feb ...19921441219
computer simulation of babesia bovis (babes) and b. bigemina (smith & kilborne) transmission by boophilus cattle ticks (acari: ixodidae).a computer model was developed to simulate the processes involved in transmission of the cattle fever parasites babesia bovis (babes) and babesia bigemina (smith & kilborne) between cattle and boophilus ticks. the model of babesia transmission was combined with a dynamic life history model for population dynamics of the tick vectors, boophilus microplus (canestrini) and b. annulatus (say). epidemiological parameters and relationships in the model include the reduction in fecundity of infected ti ...19921495038
growth of babesia bigemina parasites in suspension cultures for vaccine australian babesia bigemina vaccine strain was maintained in suspension culture for 40 days. parasite growth was compared using two tissue-culture flask sizes (25 and 75 cm2), four gas mixes (2%, 2.5%, 3% and 3.5% o2; 5% co2; and the balance n2) and four packed blood cell (pcv) volumes (7%, 9%, 13% and 18%). the best continuous parasite yields were obtained from suspension cultures in 75-cm2 flasks at a pcv of 13% and gas mixtures of 2%-3% o2, 5% co2 and the balance n2. parasite yields per mi ...19921495921
a specific dna probe which identifies babesia bovis in whole blood.a genomic library of babesia bovis dna from the mexican strain m was constructed in plasmid pun121 and cloned in escherichia coli. several recombinants which hybridized strongly to radioactively labeled b. bovis genomic dna in an in situ screening were selected and further analyzed for those which specifically hybridized to b. bovis dna. it was found that pmu-b1 had the highest sensitivity, detecting 25 pg of purified b. bovis dna, and 300 parasites in 10 microliters of whole infected blood, or ...19921496779
immunisation of cattle against theileriosis in nakuru district of kenya by infection and treatment and the introduction of unconventional tick hundred and one cross european-boran cattle (50 cows and 51 calves), on a farm in nakuru district, kenya, were immunised against theileriosis using theileria parva lawrencei and theileria parva parva stocks from another district of kenya. the stabilates used were t.p.lawrencei (mara iii) used at 10(-1.7) dilution and t.p.parva (kilae) used at 10(-1.0) dilution. the stabilates were combined and inoculated simultaneously with a short-acting formulation of oxytetracycline hydrochloride given in ...19921496782
isolation, sequence and differential expression of the p58 gene family of babesia bigemina.four copies of the gene encoding the merozoite surface protein p58 from the protozoan hemoparasite babesia bigemina were amplified from genomic dna by polymerase chain reaction (pcr) techniques, molecularly cloned and subjected to dna sequence analysis. the amplified dna (bbg7, bbg9, bbg13, bbg14) could be placed into 2 classes with respect to its size and the length of the open reading frame (orf). with the exception of a single base substitution, the sequence of bbg13 is identical to the cdna ...19921501634
ribosomal dna sequence comparison of babesia and theileria.previous studies on the taxonomy of babesia spp. (phylum apicomplexa) using morphological and life cycle characteristics have resulted in their classification into 3 subgenera, with the genus theileria being most closely related to them. using a strategy based on the direct sequence analysis of products derived by asymmetric pcr to determine the nucleotide sequences, we have tested the validity of this classification by sequencing the small subunit ribosomal rna genes amplified from 2 babesia sp ...19921518535
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