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
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
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
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
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
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
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
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
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 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
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
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
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
further studies of haemagglutinating antigens of babesia bigemina. 19734120969
the use of a slide agglutination test to demonstrate antigenic differences between babesia bigemina parasites. 19734124696
proteolytic enzyme activity in the intra-erythrocytic parasites babesia argentina and babesia bigemina. 19734129425
the preferential invasion of young erythrocytes in acute babesia bigemina infections of splenectomised calves. 19744134813
fluorescent antibody tests for babesia bigemina and b. berbera. 19724552938
detection of antibodies to babesia bigemina in dried blood samples using the indirect fluorescent antibody test. 19734578938
immunity of cattle to babesia bigemina following its elimination from the host, with observations on antibody levels detected by the indirect fluorescent antibody test. 19744594670
a direct counting technique for estimating high parasitaemias in infections of babesia argentina, babesia bigemina and plasmodium berghei. 19734595621
immunity to babesia bigemina in experimentally infected cattle. 19724629841
effects of low temperature preservation and route of inoculation on infectivity of babesia bigemina in blood diluted with glycerol. 19724630813
susceptibility of non-splenectomized and splenectomized sahiwal cattle to experimental babesia bigemina infection. 19734693430
chemoprophylaxis (imidocarb) against babesia bigemina and babesia argentina infections. 19734747036
osmotic fragility of erythrocytes in acute babesia argentina and babesia bigemina infections in splenectomised bos taurus calves. 19734792009
the isolation, separation and preservation of babesia bigemina. 19734802625
bovine babesiosis: sterile immunity to babesia bigemina and babesia argentina infections. 19734807692
babesia bigemina: immune response of cattle inoculated with irradiated parasites. 19744815017
survival of the parasitic protozoan, babesia bigemina, in blood cooled at widely different rates to -196 degrees c. 19744822484
serological diagnosis of babesia bigemina infection in cattle by the indirect fluorescent antibody test. 19684888101
the chemotherapy of babesia bigemina infection in cattle. 19654955853
circulating antigens in cattle infected with babesia bigemina or b. argentina. 19664961205
[a cytochemical study on merozoites of babesia ovis and babesia bigemina (piroplasmidea) in the hemolymph of ticks]. 19694978490
immunological studies on piroplasmosis of cattle. 3. isolation of soluble antigen of babesia bigemina and its serological properties. 19684979628
the infection of boophilus microplus with babesia bigemina. 19684984380
[fine structure of the merozoites of babesia bigemina in the ovary of boophilus microplus and boophilus decoloratus]. 19694988938
[transfer and persistence of antibodies to babesia bigemina and anaplasma marginale acquired via the colostrum]. 19704992454
dimethyl sulphoxide in the low-temperature preservation of babesia bigemina. 19714999644
[infection susceptability of various strains of boophilus to babesia bigemina as well as the influencing of ticks by host or parasite]. 19715002627
studies on the pathogenesis of babesia argentina and babesia bigemina infections in splenectomised calves. 19725081456
differential diagnosis of babesia argentina and babesia bigemina infections in cattle using thin blood smears and brain smears. 19715106907
[a capillary tube agglutination test for the detection of babesia bigemina antibodies]. 19695380274
the effect of imidocarb against babesia argentina and babesia bigemina infections of cattle. 19705464834
bovine babesiosis: the immunity of calves to babesia bigemina infection. 19685690588
[biological properties and characteristics of babesia bigemina. ionic radiation effects on infectious blood when totally infected]. 19685705119
[contribution to the problem of the natural resistance of calves to babesia bigemina]. 19695814189
sterile immunity, coinfectious immunity and strain differences in babesia bigemina infections. 19676048566
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 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
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
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 prevalence of bovine babesiosis in guyana.the serological prevalence of bovine babesiosis in guyana was determined utilising the indirect fluorescent antibody (ifa) and the complement fixation (cf) tests. babesia bigemina ifa and cf antibody activity was detected in 80% and 40% respectively of the sera from native cattle while ifa and cf antibody activity to babesia bovis was observed in 61% and 16% of the sera. the prevalence of antibody was compared between calves less than 6 months of age and mature cattle. there was little differenc ...19817020193
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
bovine babesiosis: protection of cattle with culture-derived soluble babesia bovis hereford (bos taurus) cattle were protected from severe reactions and death caused by the tick-borne protozoan hemoparasite babesia bovis, 3 months after vaccination with a cell culture--derived immunogen. the immunogen consisted of filtered, freeze-dried supernatant fluid collected from long-term cultures of babesia bovis in vitro. it was reconstituted with saponin adjuvant and injected twice subcutaneously at 2-week intervals. serum collected from vaccinated cattle caused thickening of t ...19817209532
bovine babesiosis: pathogenicity and heterologous species immunity of tick-borne babesia bovis and b bigemina infections.a total of 22 nonsplenectomized hereford, holstein-friesian, and cross-bred 18-month-old cattle were used to assess the degree of protection conferred by previous infection with babesia bovis or b bigemina against infection and disease from tick-borne challenge exposure with the heterologous species. prior infection with b bigemina or b bovis did not significantly (p less than 0.05) reduce the susceptibility of cattle to tick-borne infection and disease caused by the heterologous species. carrie ...19807212429
inhibition of babesia spp. by plastics.five commercially available plastic containers were compared with glass for toxicity toward babesia rodhaini and babesia bigemina. comparisons were made by using infectivity tests in mice (b. rodhaini) and cattle (b. bigemina). low-density polypropylene and polystyrene containers were not toxic, but two of the three polyvinyl chloride containers tested significantly reduced the viability of both species of babesia. plasticizer present in various amounts on the surface of the toxic containers was ...19817224620
development of a highly infective babesia bigemina vaccine of reduced virulence.the virulence of a strain of babesia bigemina was reduced by syringe passaging at 3 to 16-week intervals in a series of 7 calves. the calves were splenectomised 1 to 14 weeks after inoculation to induce the relapse parasitaemias used for passaging. parasites taken at relapse from the last 3 calves in the series were inoculated into splenectomised calves from which highly parasitised blood for vaccine was obtained. the vaccine produced mild infections in 32 recipient cattle. when challenged eithe ...19817236153
erythrocytic na+ and k+ changes during babesia bigemina infection in cattle.the levels of na+ and k+ in whole blood, plasma and erythrocytes were measured during the course of primary babesia bigemina infection in cattle. there were significant changes in the levels of na+ and k+ in erythrocytes, but not in plasma. erythrocytic na+ decreased and k+ increased during the course of infection, returning to normal two to three weeks later. similar ionic changes were produced in animals which were bled to cause packed cell volume depression. it is therefore suggested that the ...19807255896
efficacy of imidocarb diproprionate and primaquine phosphate in the prevention of tick-borne disease in imported hereford heifers in south korea.this paper describes the build-up of tick-borne blood parasites in a group of hereford heifers imported from new zealand to the island of jeju do, south korea. all became infected with theileria sergenti and half with babesia bigemina. an attempt was made to contain the 2 parasites by treatment with either primaquine phosphate or imidocarb diproprionate. both drugs had some prophylactic activity against t. sergenti for at least 26 days and imidocarb dipropionate eliminated b. bigemina. since t. ...19817292606
experimental transmission of babesia bigemina and anaplasma marginale to calves with the larvae of boophilus decoloratus. 19817293560
effect of experimental babesia bigemina infection on the haematological values of splenectomized white fulani calves. 19817335940
experimental transmission of babesia bigemina in sheep using infective larval tick of boophilus decoloratus. 19817342213
increased numbers of strahlenkörper in boophilus microplus ticks ingesting a blood-passaged strain of babesia bigemina.observations were made on the morphology and infectivity of babesia bigemina parasites in the gut of boophilus microplus ticks. the babesia parasites were derived from stabilates of a laboratory strain, prepared at intervals during several years of blood-passaging in cattle. increased numbers of a particular developmental stage of the parasite, considered to be a type of strahlenkörper, were observed in ticks ingesting parasites derived from the latter stages of passaging. the presence of large ...19817342228
studies on a bovine babesia transmitted by hyalomma marginatum rufipes koch, 1844.a babesia sp. was recently observed in hyalomma marginatum rufipes and found to be transmissible to bovines. further observations were carried out on this parasite and a study made of the morphology of stages in both erythrocytes and tick haemolymph. apart from babesia divergens, intra-erythrocytic parasites were not readily distinguishable from bovine babesia spp. merozoites in tick haemolymph morphologically resembled those of babesia bigemina, but they were significantly larger. this babesia ...19817345388
the retention of babesia bigemina infection by boophilus decoloratus exposed to imidocarb dipropionate during engorgement.babesia bigemina was retained in the vector boophilus decoloratus for a complete generation despite the use of the babesicide, imidocarp dipropionate, to prevent reinfection. this drug did not sterilize ticks of the b. bigemina infection as has been suggested for b. bovis.19817345389
[ultrastructure and cytochemistry of the pellicle and apical complexes of the kinete of babesia bigemina and babesia ovis in the hemolymph and oavry of the tick].the term kinete is used in this paper for the cigar-shaped, motile development stages (vermicule") of babesia occurring intra- and extracellularly in hemolymph and overy (including oocytes) of vectors, hard ticks (ixodoidea). the structure of, and cytochemical activities of hydrolases (acid phosphatase, nonspecific esterase) in the pellicle and the apical complex was studied at the fine-structural level in kinetes of babesia bigemina smith & kilborne, in hemolympho of female boophilus microplus ...19807373571
immunization of cattle with a babesia bigemina antigen in freund's complete adjuvant.three adult intact cattle and five splenetomized calves were immunized against babesia bigemina by the subcutaneous injection of an adjuvant-vaccine given twice at 3- and 4-week intervals, respectively. the antigen consisted of b bigemina parasites and erythrocytic stroma. the vaccinated adults plus one control, and the vaccinated splenectomized calves plus four comparable controls were challenge exposed at 67 and 33 days, respectively, after the last vaccine injection. all control animals died ...19807406273
serum carboxypeptidase b levels during acute and mild babesia bovis and acute babesia bigemina infections of cattle.serum carboxypeptidase b (scpb) levels were measured in splenectomised calves and in non-splenectomised cattle infected with three virulent and one avirulent strains of babesia bovis, and in splenectomised calves infected with virulent babesia bigemina parasites. scpb levels commenced falling three days post-infection in animals infected with virulent b. bovis strains and fell significanttly terminally. in animals infected with the avirulent b. bovis strain, the scpb levels were not significantl ...19807456644
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