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staining characteristics of colonies of anaplasma marginale theiler in dermacentor andersoni stiles.colonies of anaplasma marginale theiler were studied in midgut epithelial cells of adult dermacentor andersoni stiles that were infected as nymphs. the colonies were demonstrated in plastic sections (1 micrometer) and frozen sections (6 micrometer) with mallory's stain. colonies were also demonstrated in frozen sections, using direct fluorescent antibody technique. colonies were not observed in plastic or frozen sections stained by the giménez method. in all preparations, the colonies were usual ...19816175257
serologic comparisons of 4 anaplasma isolates as measured by the complement-fixation test.anaplasma marginale isolated from virginia ( vam ), from north texas ( ntam ), from florida (fam), and anaplasma ovis from idaho were used in these trials. complement-fixation antigens from each of the 4 isolates were used to compare complement-fixing antibody titers of 10 cattle infected with vam , 17 with fam, and 6 with ntam . strong cross-reactions occurred with all antigens and sera. the homologous system generally showed higher average antibody titers. the serum antibody titers occurring w ...19846203210
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
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
a case of apparent suppression of anaplasma marginale infection by eperythrozoonosis (eperythrozoon teganodes).the apparent suppression of anaplasma marginale infection by eperythrozoon teganodes in a splenectomized calf has been reported. a splenectomized calf, inoculated with 500 ml of blood having 23% erythrocytes infected with a. marginale, developed eperythrozoonosis on the fourth day post inoculation. a. marginale parasitaemia remained very low during the patent eperythrozoonosis. a. marginale parasites started to increase in number only after e. teganodes infection had been controlled with neoarsp ...19826211820
the effect of anaplasma marginale on the glycolytic pathway in bovine erythrocytes.the glycolytic process in non-infected and a. marginale-infected bovine erythrocytes was studied. the study included four enzymes: hexokinase, phosphofructokinase, pyruvic kinase and lactic dehydrogenase, and the intracellular concentrations of glucose, atp and 2,3 diphosphoglyceric acid (dpg). the activities of phosphofructokinase and lactic dehydrogenase found in non-infected bovine erythrocytes were fifty times greater than the previously reported values. glucose and dpg concentrations, hexok ...19846236033
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
immunocytochemical labeling of anaplasma marginale theiler in dermacentor andersoni stiles with peroxidase- antiperoxidase technique.colonies of anaplasma marginale in midgut epithelial cells of adult ticks that had been infected as nymphs were specifically labeled, using the unlabeled antibody peroxidase-antiperoxidase method of immunocytochemistry. visual comparison of infected and control tissue sections with the electron microscope demonstrated deposition of ring-like peroxidase-antiperoxidase complexes over organisms within the colonies. the intensity of labeling differed among organisms within a single colony, possibly ...19826285774
demonstration of anaplasma marginale in hemolymph of dermacentor andersoni by animal inoculation and by fluorescent-antibody technique.hemolymph was collected from adult dermacentor andersoni stiles that had been infected with anaplasma marginale theiler as nymphs. before hemolymph was collected, the adult ticks were either incubated and unfed at 37 c for 2.5 days or fed for 6 days on sheep. hemolymph collected from groups of 100 ticks was inoculated into susceptible splenectomized calves. smears of hemolymph from the same groups of ticks were prepared for examination by fluorescent antibody technique. hemolymph from incubated ...19836346968
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
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
[distribution of piroplasma and anaplasma marginale in calves in burundi]. 19836419686
observations on blood-borne parasites of domestic livestock in the lower juba region of somalia.the commonest parasite to be found in blood of cattle in the lower juba region is theileria mutans. antibodies against trypanosoma spp. and anaplasma marginale could be detected serologically whereas no antibodies against t. parva and t. annulata were present. a list of ticks collected between 1980 and 1982 in the above mentioned area shows that vectors of t. mutans are common. as the cattle throughout the region are indigenous somali boran it seems that endemic stability is maintained and morta ...19846441324
comparison of gloxazone, an effective but toxic anaplasmacide, with imidocarb dihydrochloride.eight calves and 15 steers were artificially infected with anaplasma marginale. when parasitaemia reached 15 per cent, groups of animals were treated with either gloxazone (356c61), or imidocarb dihydrochloride or left untreated as controls. both compounds were highly effective in the therapy of anaplasmosis. toxicological studies showed that gloxazone was unacceptably toxic in lactating cattle and also caused nephrotoxicity in rats. development work with gloxazone as an anaplasmacide has, there ...19806451008
serological evidence of exposure to anaplasma marginale in nigerian one-humped camels. 19846464312
epidemiology of tick-borne diseases of cattle in zimbabwe. ii. anaplasmosis.a survey on the incidence of antibodies to anaplasma marginale in one- to three-year-old cattle was carried out in zimbabwe using the capillary tube agglutination test. antibodies were detected in all but one of 118 batches of sera collected from different localities throughout the country. there was no clear relationship between the frequency of occurrence of positive serological reactors, which was similar in both commercial and communal farming areas, and the incidence of clinical anaplasmosi ...19846485099
demonstration of the inclusion appendage of anaplasma marginale in nymphal dermacentor andersoni.dermacentor andersoni nymphs were placed in stockinettes and allowed to feed on a splenectomized calf with experimentally induced anaplasmosis when the parasitemia was 3%-5%. nymphs were selected on each of the 6 days of feeding and every 5 days from repletion through molting to the adult stage (25 days postrepletion); they were killed and midgut tissues were processed and examined by light and electron microscopies. no stages of a marginale were seen in tissues of feeding ticks. visualization o ...19846497136
the elimination of anaplasma marginale from carrier cattle by treatment with long acting oxytetracycline. 19846517790
studies on ticks of veterinary importance in nigeria. xi. observations on the biology of ticks detached from the red-flanked duiker (cephamophys rufulatus) and parasites encountered in their blood.some aspects of the biology of amblyomma variegatum and boophilus decorolatus detached from red-flanked duikers were studied. smears were also made from the blood of the duikers and examined for the presence of parasites. anaplasma marginale was the only blood parasite found in the blood smears. compared with ticks detached from cattle, duiker ticks produced a greater number of eggs. the lengths and breadths of eggs produced by duiker ticks were greater than those of cattle ticks and unlike a. v ...19846538723
acquired cellular responsiveness in cattle cleared of anaplasma marginale 28 months earlier.the leukocyte migration inhibition test (lmit) was used to assess cell-mediated immune responses of cattle against anaplasma marginale. leukocytes from 7 of 11 cows that had been cleared of the carrier state by antibiotic therapy 28 months earlier were inhibited from their normal migration by a. marginale antigens (p less than 0.001). after reexposure to virulent organisms, all animals were positive to the lmit. there was not a significant relationship (r = 0.49) between lmit values before and a ...19836612989
development of colonies of anaplasma marginale in the gut of incubated dermacentor andersoni. 19836625314
prevalence of antibodies to anaplasma marginale in cattle from various african biotopes in central morocco, north cameroon and southeastern zaïre. 19836650023
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
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
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
immune responses of calves antigenically stimulated and challenge exposed with anaplasma marginale during tick infestation or treatment with dexamethasone.similar anamnestic antibody responses to a 2nd injection of a anaplasma marginale vaccinal antigen were observed in calves infested with the tick dermacentor albipictus and in tick-free calves. when challenge exposure of these calves to virulent a marginale was done, infestation with the tick boophilus microplus increased anemia (p less than 0.01), but did not suppress antibody production to a marginale or increase parasitemia. none of the vaccinated calves, regardless of infestation, experience ...19846711969
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
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
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
clinical and serological evidence of bovine babesiosis and anaplasmosis in st. lucia.one hundred fifty-nine holstein calves were imported into st. lucia from the u.s.a. an outbreak of babesiosis occurred 17 days post-arrival, and an outbreak of anaplasmosis occurred 5 months after importation. sera obtained 3, 6, and 12 months post-importation revealed a high prevalence of ifa titres to babesia bovis and b. bigemina 3 months after arrival and an increase in titres to anaplasma marginale 6 months after arrival. sera obtained from native cattle from several places on the island in ...19826753317
characterization of immune responses of cattle to erythrocyte stroma, anaplasma antigen, and dodecanoic acid-conjugated anaplasma antigen: humoral immunity.normal erythrocyte antigen (sonically disrupted erythrocyte stroma; ses) and two anaplasma antigens (sonically disrupted anaplasma antigen; saa, and french pressure cell-disrupted anaplasma antigen; faa) were prepared from normal and anaplasma marginale-infected blood. portions of saa and faa antigens were chemically modified by conjugation with dodecanoic acid (saada and faada). eleven cattle were vaccinated with ses, saa, saada, or faada. five weeks later, the 11 cattle, together with 3 contro ...19806768332
ultrastructural aspects of intraerythrocytic development of a venezuelan strain of anaplasma marginale.blood samples from splenectomized calves infected with a venezuelan strain of anaplasma marginale were studied by electron microscope. a. marginale appears to invade erythrocytes by the invagination of the host cell plasma membrane. the parasite reproduces by binary or multiple fission, changing from a rounded to an irregularly polyhedral form during and after division. the mature anaplasma, within the host red cell modifies the erythrocytes cytoplasma and external membrane producing pores throu ...19836845418
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
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
bovine anaplasmosis: elimination of the carrier state with injectable long-acting oxytetracycline.long-acting oxytetracycline was administered intramuscularly (20 mg/kg) at 3-day intervals to each of 16 naturally infected anaplasma marginale carrier beef cows; 8 of the 16 cows were given 3 injections and the other 8 cows were given 4 injections. four cows seropositive for a marginale served as untreated controls. rapid card agglutination and complement fixation tests were performed 5 times during the 130-day posttreatment period. all treated cows became negative to both serologic procedures, ...19836874524
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
chemotherapy to eliminate anaplasma marginale under field and laboratory conditions. 19806947300
demonstration of anaplasma marginale theiler in ticks by tick transmission, animal inoculation, and fluorescent antibody studies.cattle were inoculated with a virginia isolate of anaplasma marginale theiler and served as an infective source for laboratory-reared dermacentor andersoni stiles and d variabilis (say) nymphs. transstadial transmission of a marginale was demonstrated by feeding the newly molted adult ticks of both species on susceptible cattle and by inoculation of gut and salivary gland homogenates collected from adult ticks at postattachment days 5 and 7. oral secretions collected from the same group of ticks ...19806989298
a comparison of direct fluorescent antibody and giemsa staining for the post-mortem diagnosis of anaplasmosis.direct 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
the parasites obtained and bacteria isolated from house rats (rattus rattus linnaeus, 1758) caught in human habitations in ibadan, nigeria.a total of 169 house rats were killed in different households distributed within five localities of ibadan. a wide range of parasites were encountered. the flea, ceratophylus fasciatus was the commonest ectoparasite found. trichostrongylus columbriformis eggs were the commonest nematode and hymenolepis diminuta the only cestode. escherichia coli was the commonest bacterium found. the incidence of helminthiasis, especially h. diminuta, was generally high among rats trapped in the villages and the ...19817037672
morphologic characteristics of colonies of anaplasma marginale theiler in midgut epithelial cells of dermacentor andersoni stiles.colonies of anaplasma marginale theiler were studied in midgut epithelial cells of adult dermacentor andersoni stiles that were infected as nymphs. colonies were categorized by light microscopy into 5 morphologic types that appear to represent stages in a developmental sequence. the mean diameter of the colony types ranged from 5.64 micrometer to type 1 colonies to 10.49 micrometers of type 5 colonies. representatives of each colony type were selected by light microscopy and were sectioned for e ...19827073078
abnormal bovine erythrocyte membrane proteins and glycoproteins during and after infection with anaplasma marginale. 19827073707
infectivity for cattle of anaplasma marginale extracted from boophilus microplus ticks exposed to certain temperatures. 19827082225
the australian brown dog tick rhipicephalus sanguineus as an experimental parasite of cattle and vector of anaplasma marginale.experiments were done to explore the possible relationship between cattle, australian dog ticks (rhipicephalus sanguineus) and anaplasma marginale. calves' ears were exposed to larval, nymphal and adult ticks on 8, 9 and 7 occasions, respectively. the immature instars fed readily, but the adults attached very poorly to calves. transtadial transmission of a. marginale was achieved on 6 occasions from 9 attempts: ticks infected as larvae or nymphs were able to transmit at the subsequent stage or s ...19827082237
influence of increased temperature on anaplasma marginale theiler in the gut of dermacentor andersoni stiles.three splenectomized dairy calves were inoculated with a virginia isolate of anaplasma marginale theiler and served as an infective source for laboratory-reared dermacentor andersoni stiles nymphs. one month after molting, groups of adult ticks were incubated at 37 c for 0, 1.5, 2.5, and 7 days. gut homogenates were made from ticks representing each incubation period. twenty-four susceptible, splenectomized dairy calves were each inoculated iv with a gut homogenate extracted from 50 adult ticks ...19827091815
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
bovine anaplasmosis: clinical, hematologic, and serologic manifestations in cows given a long-acting oxytetracycline formulation in the prepatent period.the prophylactic efficacy of a long-acting oxytetracycline formulation was determined in 36 susceptible cows experimentally inoculated with anaplasma marginale. each of 10 cows in 3 treatment groups (t2, t3, t4) were given im injections of 20 mg of oxytetracycline/kg of body weight once, twice, or three times during the prepatent period. the t2 group was treated once at 1 week after experimental inoculation, the t3 group was treated 2 times (at 1 and 2 weeks) after exposure, and the t4 group was ...19827103219
elimination of naturally acquired chronic anaplasma marginale infections with a long-acting oxytetracycline injectable.four injections of a long-acting oxytetracycline (20 mg/kg) were administered at 3-day intervals to 14 naturally infected anaplasmosis carrier cattle. individual anaplasma serology titers were evaluated, using complement-fixation and rapid card-agglutination tests at frequent intervals during a 180-day posttreatment period. serologic results indicated fluctuating complement-fixation titers during the trial period. however, at trial termination, 12 of 14 animals were negative by complement-fixati ...19827165161
serologic evidence of anaplasma marginale infection in illinois white-tailed deer.a total of 175 deer and 54 cattle from crab orchard national wildlife refuge in southern illinois were tested for antibody to anaplasma marginale, using the capillary tube agglutination test. a total of 12 (6.9%) deer and 7 (13%) cattle were serologically positive. serologic prevalence in deer increased from 0 at 6 months of age to 14% at 2 1/2 or more years of age. cattle less than approximately 1 year of age were not seropositive.19827174438
the effect of incubation and prefeeding of infected rhipicephalus simus nymphae and adults on the transmission of anaplasma marginale.two batches of unfed rhipicephalus simus nymphae carrying anaplasma marginale were incubated for 72 h and 96 h respectively at 37 degrees c. fifty ticks were triturated at a time and the homogenates were used to infect susceptible cattle. others were prefed on a bovine host for 72 h before tick suspensions were prepared. the same procedure was followed, using a single batch of infected adult ticks. incubation had no effect on the infectivity of the nymphal homogenates, but prefeeding of nymphae ...19827177588
morphologic alteration of anaplasma marginale in calves treated with a dithiosemicarbazone.blood and clotted blood samples from 3 calves with anaplasmosis were examined by light and electron microscopies before and after the calves were treated twice with alpha-ethoxyethylglyoxal dithiosemicarbazone (given iv). in the treated calves anaplasma bodies were swollen and irregularly shaped and had rough surfaces when viewed by light microscopy. posttreatment electron microscopic examinations revealed swelling and vacuolation of initial bodies of anaplasma bodies, and ballooning of the vesi ...19827181188
serological studies of babesiosis and anaplasmosis of cattle.bos indicus-crossbred calves exposed to natural babesia bovis infection in wet and dry tropical environments in northern queensland were tested for antibodies using the indirect haemagglutination (iha) test. there was evidence of maternal antibodies suggesting endemicity of b. bovis in the 2 environments. within one year 35.3 to 94.6% of the calves had acquired b. bovis infection. the highest titres and most rapid conversion rates were observed just after the wet season when the tick population ...19827181776
ultrastructure of anaplasma marginale theiler in dermacentor andersoni stiles and dermacentor variabilis (say).cattle were inoculated with a virginia isolate of anaplasma marginale theiler and served as an infective source for laboratory-reared dermacentor andersoni stiles and d variabilis (say) nymphs. anaplasma marginale was demonstrated by electron microscopy in gut tissues of replete nymphal ticks and in unfed, incubated, and feeding adult ticks that were exposed to the organism as nymphs when they fed on an infected cow. the a marginale organism in replete nymphs and adult feeding ticks were morphol ...19807212430
demonstration of anaplasma marginale theiler in dermacentor variabilis (say) by ferritin-conjugated antibody technique.cattle were inoculated with a virginia isolate of anaplasma marginale theiler and served as an infective source for laboratory-reared dermacentor variabilis (say) nymphs. transstadial transmission of a marginale was demonstrated by feeding the newly molted adult ticks on susceptible cattle and by inoculation of gut homogenates collected from adult ticks at postattachment day 6. a similar gut homogenate from the same group of ticks was caused to react with a marginale-bovine antisera that had bee ...19807212431
anaplasma marginale in bovine erythrocyte cultures.bovine erythrocytes infected with anaplasma marginale were standardized with normal bovine erythrocytes at 1.4% and 3.5% parasitemia and cultured under low oxygen pressure at 37 c. the number of erythrocytes infected by a marginale appeared to increase 3.3-fold by day 11 and 4.5-fold by day 3, as determined by microscopic examination of giemsa-stained thin films of the culture suspension. anaplasma parasites in experimental cultures were proven to be viable and pathogenic by calf inoculation for ...19807212442
characterization of anaplasma marginale infection in splenectomized domestic goats.an inoculum of anaplasma marginale was given (iv) to a splenectomized domestic goat and then was serially passed through 4 additional goats. the results indicated that goats can be latent carriers at 75 days after inoculation, but not at 208 days. there was no evidence of serial passage of a marginale in goats.19817224308
transmission of anaplasma marginale theiler by dermacentor andersoni stiles and dermacentor variabilis (say).cattle were inoculated with a virginia isolate of anaplasma marginale theiler and served as an infective source for laboratory-reared dermacentor andersoni stiles and d variabilis (say) nymphs. following a molt and subsequent feeding of adult ticks on susceptible cows, transstadial transmission of a marginale occurred from cattle with parasitemias ranging from undetectable (in a carrier cow) to a peak of 27% (in an acutely ill cow). homogenates of gut tissue from unfed, incubated, and feeding ad ...19817224310
recrudescence of anaplasma marginale induced by immunosuppression with cyclophosphamide.eight doses of cyclophosphamide (5 mg/kg), at 2-day intervals between doses, were administered iv to anaplasma-carrier splenectomized calves. significant decreases in serum immunoglobulins, diminished complement-fixing antibody response, and transitory leukopenia were associated with the treatment. recrudescence of clinical anaplasma infection occurred after the 5th dose of cyclophosphate was given and was characterized by rapid increase in parasitemia, marked decrease in pcv, and mortality. the ...19817224313
isolation of anaplasma marginale from rhipicephalus simus males.approximately 100 adult rhipicephalus simus from a batch known to be infected with anaplasma marginale were used to infest an ox. fifty male ticks were manually removed from the animal's ears 9 days after infestation. these ticks were triturated and a stabilate was prepared which was injected intravenously into 2 susceptible oxen. both these animals became infected with a. marginale. the prepatent periods following inoculation of the tick suspensions before and after freezing in liquid nitrogen ...19807231925
serologic evidence of anaplasma marginale infection in white-tailed deer (odocoileus virginianus) in missouri. 19817253101
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: blood chemical changes in infected mature cows.the clinical chemical changes induced by anaplasma marginale infection were determined in 16 adult, intact cows infected with either of 2 virulent isolates and in 8 others treated with a live sheep-attenuated a marginale vaccine and were compared with the clinical chemical analyses in 7 noninfected controls. blood samples from the cows were analyzed for various serum components and during clinical disease. cows infected with the 2 virulent isolates had maximum erythrocyte parasitemias (0.5% to 6 ...19817258783
clinical chemistry of anaplasmosis: comparative serum protein changes elicited by attenuated and virulent anaplasma marginale isolates.in 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
comparative titration of anaplasma marginale antibodies by card agglutination and complement-fixation tests.the card agglutination test for anaplasmosis was improved so that bovine serum could be titrated for anaplasma antibodies. the modified test was validated when its results on 1 set of serum samples were compared with the results furnished by the complement-fixation test on the same set. the samples tested were from cows inoculated with an anaplasma vaccine or with either 1 of 2 virulent strains of anaplasma marginale. a correlation coefficient of 0.60 was calculated between the values of the tit ...19817283236
experimental transmission of babesia bigemina and anaplasma marginale to calves with the larvae of boophilus decoloratus. 19817293560
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
effect of anaplasma marginale infection upon blood gases and electrolytes in splenectomized calves. 19817328469
freeze-drying of anaplasma marginale.heparinized whole blood, heavily parasitized with anaplasma marginale, was collected from 3 splenectomized oxen. buffered lactose peptone (blp) was added to equal volumes as a stabilizer and the mixture lyophilized in 2 ml aliquots after rapid freezing. the dried material was reconstituted with 2 ml sterile water and inoculated without delay. the product remained infective for at least 6 months when stored in an ordinary household deep-freeze unit.19817335334
chemoprophylaxis of vector-borne anaplasmosis with sustained-release boluses.sustained-release oxytetracycline boluses (20%) delivering 145 to 150 mg/bolus/day were administered to complement-fixation test-negative cattle at dosages of 2.0, 2.5, and 3.0 mg/kg of body weight. subsequent challenge exposure of cattle with dermacentor andersoni stiles infected with anaplasma marginale theiler indicated that treatment with the dosage of 2.5 mg/kg prevented clinical anaplasmosis and that treatment with the dosage of 3.0 mg/kg prevented disease infection.19817340579
infection of splenectomized calves with anaplasma ovis.an anaplasma was not recovered from 2 splenectomized calves at 17 days after a ovis inoculation, but was recovered from 1 of the calves at 177 days after inoculation. in a 3rd calf exposed to a ovis, an anaplasma was recovered at 177 and 262 days after inoculation. the anaplasma recovered from these calves was determined to be a ovis on the basis of cross-infectivity trials, using anaplasma marginale.19817340580
antibody formation to babesia bovis and anaplasma marginale in calves in bolivia. 19817344191
prevalence of antibodies to babesia bovis and anaplasma marginale in dairy cattle in bolivia. 19807368318
characterization of immune responses of cattle to erythrocyte stroma, anaplasma antigen, and dodecanoic acid-conjugated anaplasma antigen: cell-mediated immunity.sonically disrupted normal erythrocyte stroma (ses) and two anaplasma antigens (sonically disrupted anaplasma antigen; saa, and french pressure cell disrupted anaplasma antigen; faa) were prepared from normal and anaplasma marginale-infected blood. the saa and faa antigens were chemically modified by conjugation with dodecanoic acid (saada and faada). significant (p less than or equal to 0.05) anti-anaplasma lymphocyte-transformation responses were obtained from all cattle given saa, saada, or f ...19807369609
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
epidemiology of bovine anaplasmosis in beef calves in northern queensland.natural infection of calves with anaplasma marginale was studied in two endemic areas of tropical north queensland. infection, assessed by a micro-complement fixation test, occurred throughout the year but was most frequent just after the summer wet season. infection was clinically inapparent. calves vaccinated with a. centrale did not show improved growth rate when compared with non-vaccinated calves. the complement fixation test was shown to be most effective in the detection of recent infecti ...19807425987
comparison of three methods of immunization against bovine anaplasmosis: an examination of postvaccinal effects.normandy calves ranging in age from 7 to 11 months were immunized against bovine anaplasmosis, using a diluted virulent anaplasma marginale stabilate of colombian origin, diluted bovine blood containing an apparently mild strain of a marginale isolated in colombia, or an attenuated a marginale vaccine of ovine origin from the united states. calves given the stabilate generally showed a moderate degree of parasitemia and reduction in packed cell volume (pcv). calves given the apparently mild colo ...19807436099
comparison of three methods of immunization against bovine anaplasmosis: evaluation of protection afforded against field challenge exposure.the efficacy of three immunization methods for bovine anaplasmosis was tested on 88 yearling normandy cattle which were challenge-exposed under field conditions in an enzootic zone in colombia, south american. a total of 30 cattle were immunized (premunized) with a presumed mild colombian isolate of anaplasma marginale; 29 calves were vaccinated with an attenuated a marginale of ovine origin; and 29 were exposed to a virulent a marginale stabilate of colombian origin. twenty-nine nonvaccinated c ...19807436100
seasonal incidence and hemoparasite infection rates of ixodid ticks (acari: ixodidae) detached from cattle in costa rica.to determine the tick species hindering the cattle industry in costa rica and to assess infection rates of ticks with three important hemoparasite species, cattle were monitored during a period of six months (october 1992-march 1993). four farms were located in the dry pacific region of the canton of tilarán and a fifth farm on the slopes of the poás volcano in a cool tropical cloud-forest ecosystem. on each farm 3 to 5 animals of 6 to 24 months of age were selected at random. all ticks were rem ...19947501871
effects of tick infestation and tick-borne disease infections (heartwater, anaplasmosis and babesiosis) on the lactation and weight gain of mashona cattle in south-eastern zimbabwe.the effects of ticks and tick-borne disease infections on the lactation and weight gain of mashona cattle were studied at mbizi quarantine station in the south-eastern lowveld of zimbabwe. twenty-nine mashona cows were allocated to 2 balanced groups and kept in separate paddocks at a stocking rate of one animal per 8 ha. one group received regular acaricide treatment to control bont (amblyomma hebraeum) and other ticks. the other group was left untreated. the cows were artificially inseminated. ...19957502343
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
16s rrna gene sequence of neorickettsia helminthoeca and its phylogenetic alignment with members of the genus ehrlichia.neorickettsia helminthoeca (tribe ehrlichieae, family rickettsiaceae) is the agent of salmon poisoning disease, which affects members of the family canidae. this bacterium is unusual in that it is the only known obligately intracellular bacterium that is transmitted via a helminth vector. the nucleotide sequence of the n. helminthoeca 16s rrna gene was determined and compared with the sequences of intracellular bacteria belonging to the alpha subgroup of the proteobacteria. the n. helminthoeca s ...19957537055
detection of anaplasma ovis infection in goats by major surface protein 5 competitive inhibition enzyme-linked immunosorbent assay.a competitive inhibition enzyme-linked immunosorbent assay (elisa) based on a major surface protein 5 (msp5) b-cell epitope conserved among anaplasma species was used to detect goats infected with anaplasma ovis. we examined strains of a. ovis isolated from goats in kenya and demonstrated that msp5 and the target b-cell epitope, bound by monoclonal antibody anaf16c1, were conserved. sera from 149 goats in four regions of kenya and from 302 goats in six u.s. states were tested for the presence of ...19957538510
epidemiology of babesiosis and anaplasmosis in south and central america.babesiosis (babesia bovis and babesia bigemina) and anaplasmosis (anaplasma marginale) affect native cattle from uruguay and northern argentina to guatemala. the distribution of babesia follows the dissemination of the tick vector. seroepidemiological studies showed that enzootic instability exist in herds in several areas of the region. however, clinical cases occurred less frequently than expected. the babesial tick infection rate is related to the vector abundance which in turn is regulated b ...19957597777
targeting ticks for control of selected hemoparasitic diseases of cattle.development in and transmission of hemoparasites by tick vectors are phenomena closely synchronized with the tick feeding cycle. in all known life cycles, initial infection of tick tissues occurs in midgut epithelial cells and transmission is effected as ticks feed after parasites have developed and multiplied in salivary glands. many factors reviewed affect development and transmission of hemoparasites by ticks including age of ticks, artificial temperature, climate and/or season, tick stage or ...19957597779
strategies for the control of one-host ticks and relationship with tick-borne diseases in south america.a variety of hemoparasites occurs in ruminants of south america (12 degrees 00'n-56 degrees 00's), but there is consensus on the significant economic impact of babesiosis (babesia bovis and babesia bigemina) and anaplasmosis (anaplasma marginale). the tick vector for the babesia spp. for the whole region is boophilus microplus which has been the most important target in control/eradication programs. boophilus microplus and many different hematophagous diptera species are considered vectors of a. ...19957597780
live vaccines against hemoparasitic diseases in livestock.live vaccines against hemoparasitic diseases in livestock are based on parasites derived from culture (theileria annulata), from blood of infected animals (babesia bovis, babesia bigemina, anaplasma centrale, (attenuated) anaplasma marginale and cowdria ruminantium), and from ticks (theileria parva). the t. annulata attenuated cultured schizont vaccine is safe for all varieties of cattle. blood derived vaccines are recommended mainly for young cattle, the age limit varying with the different vac ...19957597786
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
vaccine development from a commercial point of view.the development of a commercial vaccine comprises distinct stages. initiation of a research project is triggered by demands from the market. if commercial and technical requirements are met, a feasibility study is carried out. research is started, and aimed at formulating the product profile (what the product looks like). the product profile is subject to requirements set by the market (e.g. whether the product will fit into existing vaccination schedules) and very often technical aspects affect ...19957597789
recent developments in the molecular biology of anaplasmosis.recent applications of dna analysis, cloning, sequencing and expression technology have resulted in significant advances in our understanding of the hemoparasite anaplasma marginale. analysis of 16s ribosomal rna has confirmed a phylogenetic position close to ehrlichia sp. and cowdria ruminantium. intact genomic dna of a. marginale digested with sfii separates into bands from 14 to 170 kbp on pulse-field gels, with a total genome size of 1200-1260 kbp and g + c content of 56 mol%. major surface ...19957597790
conserved recombinant antigens of anaplasma marginale and babesia equi for serologic diagnosis.the competitive inhibition elisa (ci-elisa) format overcomes problems associated with antigen purity since the specificity of the ci-elisa depends solely on the monoclonal antibody (mab) used. therefore, the ci-elisa format is well suited for use with recombinant antigens. molecular clones expressing a conserved 19 kda protein of anaplasma marginale and a 34 kda protein of babesia equi were derived and characterized. the 19 kda a. marginale protein, conserved in all recognized anaplasma species, ...19957597796
recent developments in elucidating tick vector relationships for anaplasmosis and equine piroplasmosis.this brief review focuses first on several epidemiologically relevant aspects of anaplasmosis, including: (1) the role of male ticks as intrastadial, biological vectors of anaplasma through interhost transfer; (2) the application of molecular diagnostic assays in assessing tick vector competence and evaluating the role of chronically infected carrier cattle as sources of anaplasma marginale infection in vector ticks; (3) opportunities provided by a recently developed in vitro tick feeding system ...19957597797
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
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
heterologous strain challenge of cattle immunized with anaplasma marginale outer membranes.in 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
molecular and biological characterization of a newly isolated anaplasma marginale strain.anaplasma marginale, a rickettsial hemoparasite of cattle and other ruminants, results in significant economic losses worldwide. distinct strains of a. marginale have been identified based on differences in tick transmissibility, molecular size of surface proteins and dna restriction fragments, and reactivity to a panel of monoclonal antibodies. these different strains vary considerably in their virulence, antigenic composition, and ability to protect against heterologous challenge. in this pape ...19947858023
protein analysis of anaplasma marginale and anaplasma centrale by two-dimensional polyacrylamide gel electrophoresis.protein compositions of anaplasma marginale and a. centrale were analyzed by two-dimensional gel electrophoresis. both species had a major protein which was composed of 3-4 spots. the molecular weights of these two proteins were approximately 39 kda. however, the position of these proteins in the gels were slightly different when 2 gel maps were superimposed. five other protein spots were shared by a. marginale and a. centrale, whereas all the other protein spots were appeared to be unique to ea ...19947865577
analysis of the anaplasma marginale genome by pulsed-field electrophoresis.anaplasma marginale is a rickettsial parasite of bovine erythrocytes causing world-wide economic losses in livestock production. despite its importance, little is known about this rickettsia at a molecular level because it has not been cultured in vitro, and there is no small-animal model. although several genes have been cloned and sequenced, the gross genome structure of the organism has not yet been well characterized. we separated intact bovine erythrocytes from leucocytes, and determined th ...19937902862
molecular epidemiology of bovine anaplasmosis.bovine anaplasmosis presents a worldwide distribution. however, specific models for studying the epidemiology of the disease are not available. epidemiological modeling encounters some difficulties due to a lack of culturing techniques for anaplasma marginale, the causative agent, as well as for the lack of typing techniques to characterize strains. the chronic carrier state and the population dynamics of mechanical and biological vectors also create difficulties. in addition, conventional serol ...19947919822
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