TitleAbstractYear(sorted ascending)
exacerbation of latent erythrocytic infections in deer following splenectomy.eight adult deer and 4 fawns, from wild populations, were splenectomized and observed for evidence of hemo-parasitic relapses. the animals were maintained indoors under tick-free conditions and in the absence of known arthropod vectors. following splenectomy 2 adult deer and 2 fawns developed acute eperythrozoon infections, 3 adult deer developed acute theileria infections, 2 adult deer developed a demonstrable anaplasma marginale parasitemia, and 1 adult deer exhibited a low level parasitemia o ...19674229931
characterization of opsonins eluted from erythrocytes of cattle infected with anaplasma marginale. 19715567418
exit of anaplasma marginale from bovine red blood cells.incubation of anaplasma marginale-infected bovine red blood cells in a flow culture system resulted in a decrease of observable marginal bodies. the decrease was twice the degree of hemolysis, indicating that marginal bodies may leave red blood cells without concomitant lysis of the host cell.1975237446
study of an attenuated anaplasma marginale vaccine in mexico natural challenge of immunity in an enzootic evaluation was made of the protection induced by an attenuated anaplasma marginale vaccine in young purebred cattle against the challenge exposure of naturally transmitted anaplasmosis in enzootic areas of mexico. the cattle, which were raised in isolation units free of arthropods, consisted of 10 brown swiss calves (1 to 13 months of age) and 8 holstein calves (5 to 7 months of age). they were paired by breed, age, and body weight, and allotted to 2 equal groups. calves in 1 group were vacci ...19751137209
immunization against anaplasmosis and babesiosis: part i. evaluation of immunization using minimum infective doses under laboratory conditions.a method of immunization against anaplasmosis and babesiosis using minimum infective doses was developed under laboratory conditions. stabilates of anaplasma marginale stored at -60 degrees c were found infective when diluted 10-fold to 10(-3). stabilates of babesia argentina and babesia bigemina stored under the same conditions were infective when diluted 10-fold to 10(-1). intact calves inoculated with the above dilutions of stabilates developed moderate parasitemias and recovered from infecti ...19761006801
cross reactivity between anaplasma marginale and two plasmodium species as demonstrated by passive hemagglutination.two types of antigens were prepared from each of 3 partially purified preparations of anaplasma marginale, plasmodium lophurae, and p berghei. hemagglutination tests were conducted with homologous serums to detect antigenic relationships between these organisms. serums were also absorbed with both homologous and heterologous antigen preparations. cross reactivity between these organisms was observed.1976779540
survey of anaplasmosis in elk of the clearwater national forest (idaho).samples of blood from 27 free-roaming elk (cervus canadensis canadensis) from the clearwater national forest in north central idaho were tested by the rapid card agglutination test and complement-fixation test for the presence of antibodies against anaplasma marginale. the serum card test and complement-fixation test gave incomplete and false-positive reactions; the plasma card test did not give any reactions. anaplasma bodies or other blood parasites were not observed in stained smears of elk b ...19761275349
changes in serum concentration of phagocytosis-stimulating factor in experimentally induced bovine anaplasmosis: preliminary determine whether correlation exists between serum concentration of phagocytosis-stimulating factor (psf) and in vivo phagocytic activity, 2 splenectomized steers were inoculated with anaplasma marginale, and their serum psf concentrations were monitored. at the time of the anemic crisis, serum psf concentrations were elevated five to tenfold.197658572
resistance to anaplasmosis after elimination of latent anaplasma marginale infections.ten 30-month-old cattle (group 2) were inoculated with anaplasma marginale 6 months after the latent a marginale infection was eliminated by oral chlortetracycline therapy. in addition, 4 cattle (group 1) with no record of infection and 4 cattle (group 3) of equivalent age previously vaccinated with a killed antigen were similarly inoculated. moderate to severe clinical signs of acute anaplasmosis occurred in the group 1 (previously uninfected) cattle, whereas only 1 of the chlortetracycline-tre ...1977557302
infectivity of anaplasma marginale after ingestion by potential insect vectors.anaplasma marginale-infected erythrocytes retained viability and infectivity for at least 3 days after ingestion by hippelates pusio loew and up to 2 days after ingestion by species of tabanidae. the organism does not appear to have a developmental sequence in the insect vector.1977931144
influence of dexamethasone on the recrudescence of anaplasma marginale in splenectomized calves.dexamethasone was administered at the dose rate of 0.2 mg/kg of body weight to 11 splenectomized anaplasma-carrier calves (groups 1 and 3) on monday, wednesday, and friday for 3 weeks. observations were made on these calves and on 7 nontreated, comparable calves (group 2) to determine the influence of treatment on carrier infections. dexamethasone treatment was associated in every instance with an exacerbation of the anaplasma parasitemia and a decrease in packed red cell volume. the episode of ...1977921027
detection of antibodies in trypanosome-infected cattle by means of a microplate enzyme-linked immunosorbent assay.a micromodification of the enzyme-linked immunosorbent assay (elisa) was evaluated for its potential application in the immunodiagonsis of bovine trypanosomiasis. serum samples from infected and non-infected zebu cattle and samples from friesian cattle with experimental infections were exmained for the presence of trypanosomal antibodies. there were significant differences between the microelisa values obtained with samples from infected and non-infected cattle. during the course of infection mi ...1977333677
serum levels of conglutinin, complement, and immunoconglutinin in cattle infected with anaplasma marginale.sera from 10 splenectomized yearling cattle given massive doses of anaplasma marginale (peracute cases) were assayed for conglutinin and complement. sera from 5 nonsplenectomized yearling cattle given smaller doses (acute cases) were assayed for conglutinin, immunoconglutinin, and complement. in the peracute cases, conglutinating activity disappeared within 6 days after the cattle inoculated. in the acute cases, conglutining began to disappear at 3 weeks after inoculation and had disappeared at ...1978727576
elimination of the carrier state of bovine anaplasmosis with a long-acting oxytetracycline.a long-acting formulation of oxytetracycline (l-200) was injected at a dose level of 20 mg/kg intramuscularly into 12 yearling cattle that had been experimentally inoculated with anaplasma marginale 64 days previously. four cattle were treated twice, 4 were treated 3 times, and 4 were treated 4 times. all injections were given once ever 7 days. previous work (unpublished) with this formulation has revealed prolonged blood values following a single injection. the blood (80 ml) of each calf was in ...1978677530
methods to improve the health of cattle in the tropics: immunisation and chemoprophylaxis against haemoparasitic infections.a study of methods to improve the health of native cattle in tropical areas of colombia showed an advantage using immunisation techniques against haemoparasitic infections in comparison with other control methods. the control of anaplasmosis and babesiosis by immunisation of cattle with fully virulent anaplasma marginale, babesia argentina and b. bigemina is feasible in tropical cattle when the postimmunisation reaction is controlled by appropriate drug therapy. chemoprophylaxis was found less e ...1978664017
serologic and hematologic response of rabbits to anaplasma marginale-infected bovine zeland white rabbits inoculated with anaplasma marginale-infected bovine erythrocytes produced specific humoral antibodies to this parasite. specific antibody production as measured by the card and complement-fixation (cf) tests was maximal in 7 to 21 days after inoculation; however, none of the rabbits became infected. geometric mean cf titers of rabbits inoculated with rbc from cattle with acute anaplasmosis were significantly higher (p less than 0.001) than those of rabbits given rbc from ...1978646203
efficacy of attenuated anaplasma marginale vaccine under laboratory and field conditions in colombia.four-month-old holstein-friesian calves were inoculated with 3 different doses (1, 2, and 3 ml) of attenuated anaplasma marginale vaccine. vaccinated calves showed mild anaplasma parasitemia, slight decrease in packed cell volume, low serologic conversion, and no clinical illness. an artificial challenge exposure of vaccinated and unvaccinated calves with virulent colombian a marginale showed that the vaccine provided protection against clinical signs of the disease, including parasitemia and an ...1978629456
fluorescein diacetate staining of anaplasma marginale as a possible measure of viability.fluorescein diacetate viability-staining technique was applied to anaplasma marginale. marginal bodies took up the stain and became fluorescent. when infected red blood cells were incubated at 55 c, the number of fluorescent anaplasma decreased at a rate similar to the known loss of viability.1978629472
survey of the incidence of anaplasmosis among nigerian zebu trade cattle.sera samples from 573 nigerian zebu trade cattle were evaluated by the rapid card agglutination test for antibodies to anaplasma marginale between may and july 1977. the results showed 34 per cent reactors as against 66 per cent negatives. the above results showed a significant level of exposure to the infection among the fulani cattle managed under a husbandry system in which there is no provision for tick control. the significance of this level of exposure to anaplasma marginale in relation to ...1978664019
methods to improve the health of cattle in the tropics: conclusions and economic appraisal.the results of the immune responses of immunised and chemoprophylactically treated calves to tick-borne (boophilus microplus) challenge indicate that the system of immunisation was effective in protecting cattle against anaplasma marginale, babesia argentina (bovis), and b. bigemina. however, chemoprophylaxis was effective only against babesia spp. but not against a. marginale. both methods showed a substantial advantage over no control system when using native cattle breeds in a zone endemic fo ...1978705891
epidemiology of cattle anaplasmosis in colombia: i. prevalence and distribution of agglutinating antibodies.a survey to detect antibodies against anaplasma marginale, using the card test, was conducted on serum samples collected from cattle of cordoba department and north-eastern region of the department of antioquia in the republic of colombia. the samples were from native cattle of spanish descent (bos taurus), zebu (bos indicus) and various zebu-native crosses. the age range was between three and eight year olds. the results revealed that 90.3% of the samples were positive. all breeds showed a high ...1978705897
comparisons of the complement-fixation, indirect fluorescent antibody, and card agglutination tests for the diagnosis of bovine anaplasmosis.results of complement-fixation (cf), indirect fluorescent antibody (ifa), and card agglutination (ct) tests were statistically compared, using 380 serum samples obtained from 140 cattle which were disease-free or naturally or experimentally infected with anaplasma marginale of colombian origin. the ifa test was significantly the most sensitive for detection of amimals infected with anaplasmosis (97%); the ct test and the cf test were less so (84% and 79%, respectively). however, the most efficie ...1978358874
electron microscope studies of anaplasma marginale in an aedes albopictus culture system.anaplasma marginale was seen by electron microscopy within the cytoplasm of aedes albopictus cells in culture. anaplasma marginale was seen in free bovine rbc as well as in rbc phagocytized by ae albopictus cells. some a marginale organisms, both intracellular and extracellular, remained intact for as long as 60 days in culture, and anaplasma inclusion appendages were seen in free-lysed rbc and in lysed rbc phagocytized by ae albopictus cells. although some a marginale organisms had deteriorated ...1979525907
in vitro cultivation of anaplasma marginale: invasion of and development in noninfected erythrocytes.ovine erythrocytes infected with attenuated anaplasma marginale organisms were cultured in a suspension of normal ovine erythrocytes and normal bovine erythrocytes for 42 days. in each system, the organism showed an initial period of rapid growth followed by a gradual decrease in the percentage of parasitized erythrocytes accompanied by cyclic peaks. the percentage of infection of ovine erythrocytes were not different when normal ovine or bovine erythrocytes were added to the cultures. in vitro ...1979525898
comparative efficacy of drugs in bovine anaplasmosis.calves experimentally infected with anaplasma marginale were subjected to chemotherapeutic treatment in groups, each group receiving one drug only. observations were made on clinical signs, haematological changes, parasitaemias and levels of antibodies as measured by the complement fixation test. the most effective treatment was with imidocarb; other drugs which were apparently effective were steclin, terramycin and aureomycin in that order, while chloroquin diphosphate and camoquin gave little ...1979552672
[preparation and comparative testing of antigens for the immunodiagnosis of anaplasmosis in cattle].three antigen types were produced by ultra-sound treatment of the initial material (anaplasma marginale theiler infected blood) and its subsequent sedimentional centrifugation from 10 000 to 100 000 g. their specificity and susceptibility to the reaction complement binding (rcb) and to the capillary agglutination (ca) serological tests was comparatively checked up. antigens a and b were very active in rcb, while antigen b--in the ca reaction. by these qualities they meet the requirements and are ...1979545841
evaluation of the anaplasmosis rapid card agglutination test for detecting experimentally-infected elk.anaplasma marginale was experimentally transmitted from cattle to elk to cattle. six intact adult elk (cervus canadensis canadensis) inoculated with freshly collected heparinized blood from cattle chronically infected with a. marginale became asymptomatic carriers. although the elk did not develop clinical or hematologic evidence of infection, they became seropositive by the serum(srca) and plasma rapid card agglutination (prca) tests. blood from the experimentally-infected elk produced disease ...1979501840
a seroepidemiologic survey of three pronghorn (antilocapra americana) populations in southeastern idaho, 1975-1977.sera from 104 adult and 42 fawn pronghorn antelope (antilocapra americana) from southeastern idaho were tested against selected livestock pathogens. the numbers positive/numbers tested (% positive) were as follows: bovine virus diarrhea - adults 2/102 (2), fawns 0/41 (0);; infectious bovine rhinotracheitis - adults 27/101 (27), fawns 9/42 (22); parainfluenza 3 - adults 79/104 (76), fawns 22/42 (52); bovine adenovirus 7 - adults 42/103 (41), fawns 20/48 (48); bovine adenovirus 3 - adults 11/32 (3 ...19806246285
a comparison of direct fluorescent antibody and giemsa staining for the post-mortem diagnosis of fluorescent antibody (dfa) and giemsa staining of anaplasma marginale were compared in smears collected serially at post-mortem (pm) from 11 experimentally infected calves. once smears had been prepared and air-dried they could be held for at least 5 days before staining with either technique with no noticeable change in staining quality. dfa staining was more sensitive in detecting anaplasms in smears than giemsa staining. anaplasma spp could be differentiated from babesia bovis and b. b ...19807002139
identification of anaplasmataceae (haemobartonella) antigen and antibodies in systemic lupus antigen related to anaplasma marginale (am) (haemobartonella) was demonstrated in the glomeruli of one patient with lupus nephritis. indirect fluorescent antibodies against this rickettsia were demonstrated in all of 22 lupus sera tested, with titers ranging from 1:20 to 1:1280. geometric mean titer (gmt) was 116. fifty-eight percent of 102 controls did not react to am by indirect fluorescent antibody technique, and gmt of all controls was 10.7 immunofluorescence was eliminated by neutraliz ...19806153897
susceptibility of bos indicus crossbred and bos taurus cattle to anaplasma marginale infection.the effects of infection with anaplasma marginale in groups of bos indicus-brahman crossbred and bos taurus cattle aged 27 and 48 months were studied using the parameters of body weight change, packed cell volume, parasitaemia and humoral antibody. twenty-six animals (8 bos taurus and 18 bos indicus crosses) of each age group were infected. no significant differences between any of the groups were observed.19807414703
a comparative study of experimental anaplasmosis in bos indicus and bos taurus cattle.comparative studies were carried out on the susceptibility of 8 bos taurus and 10 predominantly bos indicus cross cows aged 48 months to anaplasma marginale infection. measurements were carried out on bodyweight, parasitaemia, haematological factors, humoral antibody response and serum transaminase levels. except for minor differences in reaction bos indicus and bos taurus animals were equally susceptible to infecton with the strain of a. marginale employed. such differences observed were not si ...19807425986
prevalence of antibodies to babesia bovis and anaplasma marginale in dairy cattle in bolivia. 19807368318
cell-mediated immune response in anaplasmosis in cattle.the cell-mediated immune response (cmir) was demonstrated during experimental anaplasma marginale infection in cattle, in vivo by the intradermic skin test and in vitro by the leucocyte migration inhibition test (lmit). the skin test showed a delayed hypersensitivity reaction which reached its maximum after 48-72 hours. histopathological examination of the skin biopsies revealed excessive infiltration by mononuclear cells and accumulation of oedematous fluid in the deeper dermal layers. for lmit ...19817256829
anaplasma ovis in idaho sheep.blood samples from 16 anaplasmosis complement-fixation (cf) positive sheep from a flock near cambridge, idaho, were inoculated into 3 intact sheep and 3 splenectomized calves. the 3 sheep became cf positive, and 2 developed parasitemia. none of the 3 calves had signs of anaplasmosis, but all became ill when they were subsequently challenge exposed with blood from known carriers of anaplasma marginale. after a 75-day observation period, blood from the recipient intact sheep was subinoculated into ...19817258767
clinical chemistry of anaplasmosis: comparative serum protein changes elicited by attenuated and virulent anaplasma marginale a comparative study of the clinical chemical changes during anaplasma marginale infection, 16 intact mature cows were infected with either of 2 virulent isolates. eight others were treated with a live a marginale vaccine (sheep-attenuated) and 7 were maintained as controls. before and during patency, samples of blood from the cows were analyzed for total wbc, parasitemia, card test titer (ctt), total protein, albumin, and globulin fractions. in the cows inoculated with virulent isolates, albu ...19817258784
attempts to transmit anaplasma marginale with hippobosca rufipes and stomoxys calcitrans.three attempts to transmit anaplasmosis with field collections of hippobosca rufipes were unsuccessful, despite the fact that the flies had been fed initially on splenectomized cattle acutely infected with anaplasma marginale. however, 1 out of the 3 attempts, made concurrently with the others, to transmit this organism with stomoxys calcitrans was successful. the prepatent period was 27 days.19817312304
infectivity for cattle of anaplasma marginale extracted from boophilus microplus ticks exposed to certain temperatures. 19827082225
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
influence of parasitemia level at feeding on development of anaplasma marginale theiler in dermacentor andersoni stiles.four splenectomized dairy calves were inoculated with a virginia isolate of anaplasma marginale theiler and served as an infective source (donor) for laboratory-reared dermacentor andersoni stiles nymphs. two donor calves developed higher parasitemias during tick feeding than did the 2 other donor calves. one month after molting, adult ticks were incubated at 37 c for 2.5 days to stimulate development of colonies of a marginale, and homogenates of gut were made from ticks fed on each donor calf. ...19836869951
observations on anaplasmosis following field exposure to heavy and light infestations with boophilus microplus.two groups of normandy calves were exposed to heavy (mean half body count = greater than 300) or light (mean half body count = 9) natural infestations with boophilus microplus. all of the calves became infected with anaplasma marginale. despite the difference in tick challenge level, there was no significant difference in the incubation period, increase in body temperature, level or duration of anaplasma parasitemia, decrease in packed cell volume, or complement-fixing antibody response, between ...19836685402
infectivity virulence and immunogenicity of anaplasma centrale live blood vaccine.cross-bred bos taurus calves, aged between 6 and 8 months, were inoculated with the onderstepoort anaplasma centrale live blood vaccine. one group of 15 calves were inoculated once only, while a 2nd group of 15 were revaccinated 6 months later. all the animals were challenged with approximately 1 x 10(10) anaplasma marginale parasites of a known virulent strain 8 months after the first vaccination. the results of blood smear examination and the card agglutination test indicated that only 20 out ...19836348636
effects and use of a modified live anaplasma marginale vaccine in beef heifers in california.eighty-one 11-month-old, nonpregnant, anaplasma marginale-seronegative beef heifers were allotted to 2 groups for evaluation of a modified live a marginale vaccine (n = 50 for vaccinated group and n = 31 for nonvaccinated group). the vaccine induced a mild form of anaplasmosis, as evidenced by a significant (p less than 0.01) decrease in the packed cell volume (pcv) between days 31 and 46 after vaccination. the lowest pcv was 11%, and 3 heifers had a pcv less than 20%. slight lethargy was eviden ...19836874525
comparison of proteins synthesized by two different isolates of anaplasma marginale.we present results on the initial definition of proteins synthesized by two isolates of anaplasma marginale. bovine erythrocytes infected with a. marginale were radioactively labeled with [35s]methionine or a 3h-amino acid mixture during short-term in vitro culture. the labeled proteins were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. this technique revealed protein bands of various apparent molecular weights from less than 14,000 to greater than 200,000. the bands obs ...19836852911
demonstration of colonies of anaplasma marginale in the midgut of rhipicephalus simus.rhipicephalus simus nymphs were allowed to feed on a cow experimentally infected with the bw-strain of anaplasma marginale from republic of south africa, and they were studied as adults. colonies were demonstrated by light microscopy in midgut epithelial cells of adult ticks that were unfed (as adults), incubated, or prefed for 72 hours on a cow. the colonies occurred in 5 different morphologic types (1 to 5) that were similar to those described previously for a virginia isolate of a marginale i ...19836660614
prevalence of antibodies to anaplasma marginale in cattle from various african biotopes in central morocco, north cameroon and southeastern zaïre. 19836650023
response of cattle upon reexposure to anaplasma marginale after elimination of chronic carrier infections.sixteen cattle serotest-negative for anaplasmosis with either no previous exposure (2 animals) or cleared 8 months earlier of their carrier state by chemotherapy (14 animals) were each exposed to anaplasma marginale. anaplasma serotest titers were determined by complement-fixation and rapid card agglutination tests conducted during a 63-day trial period. serologic reactions indicated that all cattle (both groups) were converted to seropositive by the 21st day after exposure. fluctuations in pcv ...19846731981
a rapid staining procedure for anaplasma marginale in bovine erythrocytes.a commercial product that stains cells in less than 1 minute was compared with the giemsa and the wright-giemsa methods for detection of the intraerythrocytic parasite, anaplasma marginale, in bovine blood smears. the total number of a marginale-infected erythrocytes detected in 5 microscope fields of 18 different samples was determined for each staining procedure. in samples where less than 2% to greater than 25% of the rbc were infected, statistical analysis of the data indicated that the rapi ...19846208825
anaplasma infections in wild and domestic ruminants: a review.anaplasma marginale can be transmitted, will grow and can survive in a large number of domestic and wild animals. it is pathogenic in cattle, and usually produces nonapparent or mild infections in other species. anaplasma marginale has been recovered from cattle, sheep, goats, water buffalo (bubalus bubalis), white-tailed deer (odocoileus virginianus), mule deer (odocoileus hemionus hemionus), black-tailed deer (odocoileus hemionus columbianus), pronghorn (antilocapra americana americana), rocky ...19846716555
immune serum against anaplasma marginale initial bodies neutralizes infectivity for cattle.the first demonstration of immune serum-mediated neutralization of anaplasma marginale and identification of the involved surface antigens is presented. anaplasma marginale initial bodies were purified from parasitized erythrocytes by using ultrasonic disruption and differential centrifugation. the initial bodies were morphologically intact, as determined by electron microscopy, were not agglutinated by anti-bovine erythrocyte sera, and were infective. sodium dodecyl sulfate polyacrylamide gel e ...19846736645
demonstration of vaccine-induced immunity to anaplasmosis without induction of persistent postvaccinal complement-fixing and agglutinating antibodies in yearling steers.the protective effect and anti-anaplasma complement-fixing and agglutinating antibody responses induced in yearling steers by vaccination with an inactivated anaplasma marginale vaccine were evaluated by challenge exposure. eleven 12- to 14-month-old hereford x angus steers were randomly allotted into 6 principals and 5 controls. the principals were injected im with 5 ml of vaccine on days 0 and 21. on day 70, the 11 steers were challenge exposed by iv inoculation of a marginale-infected blood. ...19853994127
evaluation of jackrabbits as nonruminant hosts for anaplasma marginale.two black-tailed jackrabbits (lepus californicus), 1 splenectomized and 1 intact, were inoculated with 0.2 ml of a 1:5 dilution of a florida anaplasma marginale stabilate. five months later, both hares were inoculated with 1 ml of whole blood from a calf with acute anaplasmosis. neither hare developed any signs of clinical anaplasmosis. pooled blood (7 ml) from these jackrabbits which was inoculated into 2 anaplasma-susceptible, splenectomized calves failed to induce hematologic or serologic sig ...19853994131
observations on erythrocytic acetylcholinesterase activity in experimentally induced anaplasmosis in calves.erythrocytic acetylcholinesterase (ache) activity was assessed in splenectomized bovine calves inoculated with anaplasma marginale. other parameters, i.e., haematological values (haemoglobin, packed-cell volume, and total erythrocytic count), percentage parasitaemia and the ensuing host reactions during anaplasma infection were also studied in relation to ache activity. there was significant inhibition of red blood cell-ache activity commencing soon after inoculation of infected blood; this prec ...19853992879
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
percutaneous infection of nymphal dermacentor andersoni with anaplasma marginale.newly replete nymphal dermacentor andersoni (principals) were percutaneously exposed to anaplasma marginale by injection of either intact or lysed infected bovine erythrocytes. control nymphs were fed on calves with anaplasmosis. the subsequently molted adults were examined for infection by light microscopy, and companion ticks were tested for infectivity by allowing them to feed on susceptible calves. when they fed as adults, both control ticks and percutaneously inoculated principals transmitt ...19863752672
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
tick infestations on livestock in the yemen arab republic and their potential as vectors of livestock diseases.a survey of ticks on cattle, camels, sheep, goats and donkeys in four different geographical locations of the yemen arab republic (yar) was carried out to provide more information on the possible risk of tick-borne diseases to imported exotic cattle included in the yar's plans for livestock development. the most abundant ticks were hyalomma spp. particularly on camels. ticks found on cattle included hyalomma spp., amblyomma variegatum, boophilus annulatus and rhipicephalus spp. in general with t ...19873603710
vaccination with anaplasma centrale: response after an experimental challenge with anaplasma marginale.the haematological and clinical responses to vaccination with anaplasma centrale and to subsequent challenge with anaplasma marginale were evaluated. twenty holstein steers 14 to 16 months of age were divided into two groups of 12 and eight animals respectively (groups i and ii). group i was inoculated on day zero with 10(7) a. centrale-infected erythrocytes and group ii was kept as a control. on day 125 both groups were challenged with 5 x 10(7) a. marginale-infected erythrocytes. a. centrale i ...19873629722
an enzyme linked immunosorbent assay to diagnose babesia bovis infection in cattle.the optimum gel filtration fraction from lysate of babesia bovis infected erythrocytes was determined for use as an antigen in an elisa to diagnose b. bovis infection in cattle. of four enzyme labels tested, horseradish peroxidase was the most suitable. the assay is both sensitive and specific in detecting antibody for 2-4 years after a single infection. false positive reactions were obtained only with some sera from some anaplasma marginale infected cattle.19873106957
the persistence of colostral anaplasma antibodies and incidence of in utero transmission of anaplasma infections in calves under laboratory conditions.twenty-six calves, born from 25 anaplasma-infected, intact and splenectomized cows, from a herd kept under strict tick-free laboratory conditions, were monitored for the presence of anaplasma antibodies, using the rapid card agglutination test. serum was collected at birth, weekly for 12 weeks, and then monthly for approximately 6 months. specific antibodies passively acquired could be detected in calf sera for an average period of 8 weeks after birth. calves that remained positive for longer th ...19873444609
characterization of an immunoprotective protein complex of anaplasma marginale by cloning and expression of the gene coding for polypeptide am105l.immunization with an anaplasma marginale surface protein complex containing two polypeptides (am105u and am105l), each having a molecular weight of 105,000, protected cattle against challenge with virulent organisms. these polypeptides were immunoprecipitated together from detergent extracts of a. marginale by a neutralizing monoclonal antibody. after surface radioiodination of intact parasites, both am105u and am105l contained the radiolabel. to define the structural and antigenic relationships ...19872443451
characteristics of an attenuated anaplasma marginale of deer origin as an anaplasmosis vaccine.a fully virulent field anaplasma marginale isolate, passaged to a splenectomised white tailed deer, lost virulence for cattle after 18 months in the non-bovine host. this attenuated a. marginale produced a mild response in four 18-month-old holstein steers characterised by an average 2.4% parasitaemia, a 13% drop in pcv and a positive serological response. all vaccinated steers were immune to challenge with a fully virulent, heterologous a. marginale when compared with non-vaccinated controls.19883400115
isolation and restriction endonuclease cleavage of anaplasma marginale dna in situ in agarose.bacterial restriction endonucleases were used to produce dna cleavage patterns that could be useful as tools to study the relatedness among anaplasma marginale isolates. bovine erythrocytes infected with a. marginale were lysed, washed, and embedded in agarose. the embedded erythrocytes and bacterial pathogens were partially digested by sequential infiltration of the agarose with acetone, lysozyme, sodium dodecyl sulfate, and proteinase k. the unfragmented genomic dna was left supported and prot ...19882838504
nucleic acid levels in anaplasma marginale during experimentally induced bovine anaplasmosis.the dna and rna concentrations in uninfected and anaplasma marginale-infected bovine erythrocytes were determined. bovine anaplasmosis was experimentally induced and the nucleic acid levels were followed during the development of the a. marginale infection. two distinct growth stages were found, the "multiplication" stage and the "transfer" stage. based on this hypothetycal developmental cycle, the amount of dna and rna per anaplasma initial body was estimated as 73.1 x 10(-3) pg and 45.7 x 10(- ...19882451913
detection of anaplasma-marginale-infected tick vectors by using a cloned dna probe.anaplasmosis is the most widely distributed of several important tick-borne diseases that constrain cattle production throughout much of the world. evaluation of the effectiveness of disease control strategies that integrate vaccination with tick control requires the ability to monitor tick and cattle infection rates. to detect anaplasma marginale in ticks and bovine erythrocytes, a 2-kilobase dna fragment from a cloned a. marginale gene coding for a surface protein having a mr of 105,000 was pr ...19883422471
cloned dna probes identify anaplasma ovis in goats and reveal a high prevalence of infection.anaplasma organisms are observed in erythrocytes from goats with anemia and weight loss in kenya. three anaplasmas have been isolated in nature, anaplasma ovis, anaplasma marginale, and anaplasma centrale. the two recognized species, a. ovis and a. marginale, are known to infect goats. since only a. ovis causes clinical disease in goats, the anaplasma species in goats in kenya were identified. to detect a. ovis, a 9.6-kilobase-pair section of genomic dna was cloned into pbr322 (pao12a) and was u ...19892592538
detection and quantitation of anaplasma marginale in carrier cattle by using a nucleic acid probe.cattle which have recovered from acute infection with anaplasma marginale, a rickettsial hemoparasite of cattle, frequently remain persistently infected with a low-level parasitemia and serve as reservoirs for disease transmission. to fully understand the role of these carriers in disease prevalence and transmission, it is essential that low levels of parasitemia can be accurately detected and quantitated. we have developed a nucleic acid probe, derived from a portion of a gene encoding a 105,00 ...19892915021
seroprevalence of anaplasmosis in the red river plains and south-east areas of louisiana.the indirect fluorescent antibody test was used to detect antibodies to anaplasma marginale in serum samples collected from cattle in the red river plains and south-east areas of louisiana. convenience sampling of herd clusters was used. a reactor rate of 7.8% was found in 11,085 samples. beef cattle had a 11.2% reactor rate compared with 3.8% for dairy cattle. the angus and angus cross-breed group had the highest reactor rate.19892675458
immunodiagnosis of and immunoprophylaxis against the haemoparasites babesia sp. and anaplasma sp. in domestic animals.the haemoparasites babesia bovis and anaplasma marginale are extremely important pathogens of cattle, affecting more than 300 million animals worldwide. species of less importance affect cattle, dogs, horses and sheep. no vaccine is available for widespread usage. this review summarises existing immunodiagnostic and immunoprophylactic methods currently available for these diseases and reports on future immunoprophylactic methods.19902132684
comparison of a dna probe, complement-fixation and indirect immunofluorescence tests for diagnosing anaplasma marginale in suspected carrier cattle.most estimates of the prevalence of anaplasmosis have been based on serologic data using the complement-fixation (cf) and/or card agglutination tests. since these tests are considered to be only about 50 percent reliable for detecting carrier cattle in enzootically stable herds, the need for more sensitive diagnostic tests is widely recognized. the objective in the present study was to compare the sensitivity of the cf test with that of the indirect immunofluorescence (iif) test and a recently d ...19902260275
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
[natural anaplasma marginale infection in 2 cattle herds with different levels of boophilus microplus tick infestation].the dynamics of natural infections by anaplasma marginale was studied in two adjacent dairy farms with different levels of boophilus microplus infestation. the farms were located in the enzootic area of bovine anaplasmosis of the northwest of argentina. the study was carried out in 35 calves from birth in march-august 1985 to march 1986. the infection rate by a. marginale was evaluated by the observation of blood films and by determination of specific antibodies. the degree of infestation by b. ...19902132783
recombinant dna probe detecting eperythrozoon suis in swine blood.a genomic library to eperythrozoon suis dna was constructed in lambda gt11, and from this library, e suis clone ksu-2 was identified as a potential diagnostic probe. in hybridization experiments that used 100-microliters samples of blood collected in chaotropic salt solutions, the ksu-2 probe hybridized strongly with purified e suis organisms and blood samples from splenectomized swine that were parasitized with e suis. however, the probe under stringent conditions did not give radiographic indi ...19902240802
mass screening of cattle sera against 14 infectious disease agents, using an elisa system for monitoring health in livestock.mass screening elisa methods were developed for testing cattle serum for antibodies against 14 common livestock diseases simultaneously. the absorbance values were transformed to a %elisa (spectrophotometric antibody end point) by a computer interfaced with a microplate reader. a histogram indicating a cutoff point and a report for the veterinarian also was generated. the computer program produced a print-out of the antibody profile for each animal tested, the antibody concentration against each ...19911767993
preliminary observations on ticks and tick-borne diseases in the north west province of cameroon. i. babesiosis and anaplasmosis.during a survey on ticks and tick-borne diseases in the north-western cameroon at the bamenda cattle market, the ticks identified were boophilus annulatus (20%) and b. decoloratus (80%). more than 50% of the ticks were collected during the dry season. of 524 blood smears 47.3% were positive for babesia bovis, 31.1% for b. bigemina and 2.2% for anaplasma marginale. 19.4% were negative.19911824132
identification of anaplasma marginale long-term carrier cattle by detection of serum antibody to isolated msp-3.rapid and accurate detection of anaplasma marginale-infected cattle would enhance anaplasmosis control procedures and evaluation of vaccines. current tests based on detection of antibodies in serum are not widely used for several reasons, including the occurrence of either false-positive or false-negative results. we evaluated binding of antibodies in serum to a subunit antigen isolated from a. marginale initial bodies--major surface protein 3 (msp-3). msp-3 was detected in lysates of eight geog ...19911890178
16s ribosomal dna amplification for phylogenetic study.a set of oligonucleotide primers capable of initiating enzymatic amplification (polymerase chain reaction) on a phylogenetically and taxonomically wide range of bacteria is described along with methods for their use and examples. one pair of primers is capable of amplifying nearly full-length 16s ribosomal dna (rdna) from many bacterial genera; the additional primers are useful for various exceptional sequences. methods for purification of amplified material, direct sequencing, cloning, sequenci ...19911987160
efficacy of purified anaplasma marginale initial bodies as a vaccine against anaplasmosis.anaplasma marginale initial bodies of the florida strain were purified from infected erythrocytes using a combination of ultrasonic disruption, nonionic detergent and differential centrifugation. immunochemical analysis revealed at least 12 a. marginale proteins in the molecular mass (m) range 81-15 kda with a prominent band at 38 kda. several of these proteins remained insoluble in the presence of nonionic detergent. preparations of purified anaplasma initial bodies contained negligible erythro ...19912027888
identification of immunodominant polypeptides common between anaplasma centrale and anaplasma marginale.high titered antibody from rabbits immunized with anaplasma centrale or from cattle recovered from a. centrale infection bound predominantly to several 33-36 kda polypeptides present in both a. centrale and the israel-nt isolate of anaplasma marginale. high titered bovine antibody against the israel-nt isolate of a. marginale also reacted predominantly with a. centrale polypeptides in this size range. the immunodominance of the 33-36 kda polypeptides and their cross-reactivity indicate that thes ...19911949581
detection of anaplasma marginale rickettsemia prior to onset of clinical signs by using an antigen capture enzyme-linked immunosorbent antigen capture enzyme-linked immunosorbent assay was developed by using monoclonal antibodies to conserved epitopes on the anaplasma marginale msp1a surface protein. the assay sensitivity was 1.1 (+/- 0.5)% parasitized erythrocytes, and all infected cattle were detected prior to development of 2.0%-parasitized erythrocytes. positive tests preceded the onset of anemia by a mean of 2 days. the assay was specific for anaplasmosis, as demonstrated by nonreactivity with another common hemoparasit ...19911885753
analysis of protein compositions and surface protein epitopes of anaplasma centrale and anaplasma marginale.protein composition was compared and epitopes were analyzed among the isolates of anaplasma centrale and a. marginale by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoblotting using bovine antisera and monoclonal antibodies, and enzyme-linked immunosorbent assay. common and unique proteins were found among the isolates. all isolates tested had a major surface protein with an apparent molecular weight of 38 to 40 kilodalton which had slight molecular size variations between spe ...19911713792
seroprevalence survey for anaplasma marginale-infection of austrian cattle.a serologic survey study of 5,076 austrian cattle farming herds was carried out in the period of december 1988 till march 1990. one animal was randomly selected from each herd and the antibody titer against anaplasma marginale in blood serum samples was evaluated by means of the complement fixation test. the number of these tested blood samples was 3.6% of 140,081 cattle herd farms of austria. 109 (2.1%) of the tested animals showed positive titers (1:10) against anaplasma marginale, in relation ...19921621479
prevalence of babesia bovis and anaplasma marginale at selected localities in sri lanka.sera were collected from a minimum of 20 cattle aged nine to 36 months at each of 14 localities in five climatic zones of sri lanka. sera were tested for antibodies to babesia bovis and anaplasma by an indirect fluorescent antibody test and a card agglutination test, respectively. antibodies to b. bovis and anaplasma were detected in all samples tested from each of 14 and 12 localities respectively. in general, prevalences were consistently high among localities below 1,200 m and lower and more ...19921306921
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
a cloned dna probe for cowdria ruminantium hybridizes with eight heartwater strains and detects infected sheep.the dna probe pcs20, which was cloned from the dna of the crystal springs heartwater strain from zimbabwe, cross-reacted with dnas of heartwater strains from all endemic areas, including four heartwater strains from zimbabwe, two strains from south africa, one strain from nigeria, and the gardel strain from the caribbean island of guadeloupe. by nucleic acid hybridization, the pcs20 dna probe detected cowdria ruminantium dna in all dna preparations made from plasma samples from infected sheep be ...19921572987
single-step technique for staining anaplasma marginale in bovine blood smears.three available differential stains, camco-quik, diff-quik, and wright-giesma were compared for detection of intraerythrocytic anaplasma marginale in bovine blood smears. in samples where < 1% to more than 51% of the rbc were infected, statistical analysis of the data indicated no significant difference in the detection of a marginale with camco-quik or diff-quik stains. however, a significantly lower percentage of infected rbc were detected when blood smears were stained with the wright-giemsa ...19921280925
a clinical trial of buparvaquone in the treatment of east coast fever.a clinical trial was conducted to test buparvaquone (butalex; coopers pitman-moore) in the treatment of east coast fever under field conditions in kenya. data from 229 cases were analysed following treatment with one (69), two (142) or three (18) doses at 2.5 mg/kg. the majority of cattle (95.2 per cent) were exotic (bos taurus) or improved (bos taurus cross bos indicus) and 39.3 per cent were infected with anaplasma marginale. there was an overall recovery rate of 85.6 per cent, with 90.1 per c ...19921441098
anaplasma marginale: failure of sera from immune cattle to confer protection in passive-transfer experiments.high levels of immunity to anaplasma marginale were induced in cattle either by vaccination using sonically disrupted a. marginale-infected erythrocytes or by repeated infection with different strains of the rickettsia. in both instances, high levels of anti-a. marginale antibody were detected in the sera of the immune cattle by immunoblotting. serum from one animal that had been made immune by repeated infection was transferred intravenously to a. marginale-susceptible calves (three non-splenec ...19921495919
a comparison of field tick infestation on n'dama, zebu and n'dama x zebu crossbred cattle.tick burdens, estimated from cumulative tick counts, were determined on n'dama, zebu and f1 n'dama x zebu crossbred cattle. n'dama showed significantly fewer ticks than the zebu and f1 cattle (p < 0.001). a previous trypanosomosis infection did not affect tick burdens on the three genotypes. amblyomma variegatum had a prevalence of 84.8% and hyalomma spp. 15.2%, with the ratio similar on all cattle breeds. trypanosomosis infection increased the serological prevalence of anaplasma marginale in ze ...19938493760
application of enzyme-linked immunosorbent assay for epidemiological studies of diseases of livestock in the tropics of mexico.this study was conducted at the centre for research, teaching and extension in tropical livestock (centro de investigación, enseñanza y extensión en ganadería tropical) of the faculty of veterinary medicine of the national autonomous university of mexico. during the latter part of 1986 and throughout 1988 and 1989, the herd of holstein x zebu cattle at the university was tested for igg antibodies to twenty-one viral, bacterial, rickettsial and parasitic agents. antigens prepared from twenty infe ...19938219327
antigen recognition on anaplasma marginale and bovine erythrocytes: an electron microscopy study.the reactivity of sera from anaplasma marginale-infected bovine with red blood cells and with purified anaplasma bodies was analyzed by electron immunomicroscopy. red blood cells from non-infected and from anaplasma-infected cows and a. marginale bodies separated from parasitized erythrocytes, were incubated with control, pre-immune and immune sera followed by anti-bovine igg-peroxidase. immune sera from cows infected with the venezuelan and florida isolate reacted with red blood cell membranes ...19937504852
expression and immune recognition of the conserved msp4 outer membrane protein of anaplasma marginale.defining conserved, protective epitopes is essential to the design of an effective vaccine against bovine anaplasmosis. msp4, one of six initial body proteins recognized by a neutralizing serum, is conserved among anaplasma marginale isolates at both the protein and the dna levels. sera from cattle immunized with an outer membrane fraction of a. marginale and protected from a virulent challenge bind msp4. the gene for msp4 has been cloned, and the recombinant protein has been expressed, isolated ...19937693596
sheep-adapted anaplasma marginale maintains virulence for cattle. 19938343094
heterologous strain challenge of cattle immunized with anaplasma marginale outer this study, we tested the hypothesis that outer membrane immunization would induce protection against an antigenically variant strain. outer membranes were isolated from the virginia strain of anaplasma marginale using density gradient centrifugation, combined with saponin adjuvant, and used to immunize friesian cattle in zimbabwe. immunized cattle developed high antibody titers (80,000-160,000) against outer membrane polypeptides including msp-2 and msp-5 in both the homologous virginia and ...19947810060
seroprevalence of bovine anaplasmosis in oklahoma from 1977 to 1991.the prevalence of anaplasmosis in oklahoma cattle was determined on the basis of the standardized anaplasma marginale complement fixation test on 20,155 sera submitted to the oklahoma animal disease diagnostic laboratory during a 15-year period. rates of seropositivity ranged from 4.7% to 17.6% on samples submitted for anaplasmosis testing of adult cows. the geographic distribution of recorded cases of anaplasmosis was 35 oklahoma counties in 1977 and 48 oklahoma counties in 1991.19948068752
putative adhesins of anaplasma marginale: major surface polypeptides 1a and 1b.genes for the msp1a and msp1b subunits of the anaplasma marginale surface antigen complex msp1 were previously cloned and expressed in escherichia coli. we report here the localization of msp1a and msp1b polypeptides on the surface of recombinant e. coli by using a live cell indirect immunofluorescent antibody assay. recombinant e. coli cells expressing the msp1 alpha gene or the msp1 beta gene encoding the msp1a and msp1b polypeptide subunits, respectively, were shown by a culture recovery adhe ...19947927726
molecular basis for vaccine development against anaplasmosis and babesiosis.immunization of livestock against the erythroparasitic pathogens anaplasma marginale, babesia bigemina, and babesia bovis with safe and effective killed vaccines is not yet feasible on a practical basis. however, the immune protection afforded by recovery from natural infection and premunition indicates that microbial epitopes capable of inducing immunity exist and that the bovine immune system can be primed appropriately. induction of protection by immunization with killed parasite fractions, e ...19957597787
susceptibility to different tick genera in gambian n'dama and gobra zebu cattle exposed to naturally occurring tick infestations.tick collection on one side of the body and whole tail was performed weekly over one year on 11 gambian n'dama (bos taurus) and 11 gobra zebu (bos indicus) cattle to assess breed susceptibility to naturally occurring ticks. enzyme-linked immunosorbant assay was also performed to assess the serological prevalence of anaplasma marginale antigen and babesia bigemina antibody. packed red cell volume was measured and liveweight gain was recorded. significantly higher numbers of amblyomma variegatum ( ...19957652946
detection of theileria annulata in blood samples of carrier cattle by pcr.we report the detection of theileria annulata, the causative agent of tropical theileriosis, by pcr in blood samples obtained from carrier cattle. the assay employs primers specific for the gene encoding the 30-kda major merozoite surface antigen of t. annulata. a 721-bp fragment was amplified from blood samples taken monthly from calves experimentally infected with one of four different stocks of t. annulata originating in either mauritania, portugal, spain, or turkey. at the end of the experim ...19958567902
detection of anaplasma marginale dna in bovine erythrocytes by slot-blot and in situ hybridization with a pcr-mediated digoxigenin-labeled dna probe.a 409-base pair (bp) dna fragment derived from the msp-1 beta gene of anaplasma marginale was amplified and simultaneously labeled with digoxigenin-11-dutp by a polymerase chain reaction (pcr) assay. the resulting digoxigenin-labeled 409-bp pcr product was used as a probe for slot-blot and in situ hybridization to detect a. marginale dna from experimentally infected bovine erythrocytes. the hybrid formation was detected with alkaline phosphatase-conjugated anti-digoxigenin antibody and substrate ...19958580166
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