amblyomma americanum: area control with granules or concentrated sprays of diazinon, propoxur, and chlorpyrifos. 197657127
distribution and prevalence of spotted fever group rickettsiae in ticks from south carolina, with an epidemiological survey of persons bitten by infected ticks removed from human hosts were tested for the presence of spotted fever group rickettsiae from 1974 through 1976. spotted fever group rickettsiae were detected in dermacentor variabilis, amblyomma americanum, amblyomma maculatum, and ixodes scapularis. persons from whom positive ticks were removed in 1974 and 1975 were questioned about ensuing illness. eleven of 51 persons from whom rickettsia-positive d. variabilis were removed reported some unexplained combination of symptoms compati ...1978103448
comparisons of the foveae dorsales in male and female ixodid ticks amblyomma americanum, a. maculatum, dermacentor andersoni and d. variabilis (acari: ixodidae). 1979537001
rocky mountain spotted fever (tick-borne typhus) in south carolina: an educational program and tick/rickettsial survey in 1973 and 1974.because the incidence of spotted fever is increasing in south carolina, campaigns were carried out in 1973 and 1974 to provide the public and medical practitioners, through pamphlets and news media, with information about spotted fever and the ticks which transmit the causative agent, rickettsia rickettsii. people were also invited to save and submit live ticks removed from vegetation, animals and humans, for examination by the hemolymph test. a total of 1,186 ticks consisting of 987 dermacentor ...1975811127
the ecology and behavior of the lone star tick (acarina: ixodidae). x. adult overwintering and survival in woodlots. 1976978696
trypanosomes in amblyomma americanum from oklahoma. 1976978370
control of fluid secretion by isolated salivary glands of the lone star tick. 19751194704
effect of imported fire ant (hymenoptera: formicidae) invasion on lone star tick (acarina: ixodidae) populations. 1977606827
the relationship of phosphodiesterase and cyclic amp to the process of fluid secretion in the salivary glands of the ixodid tick amblyomma americanum.phosphodiesterase (pde) activity in the salivary glands of the female. amblyomma americanum decreased as the tick progressed from a slow to a rapid phase of feeding, while the rate of fluid secretion increased when glands were stimulated with cyclic amp and theophylline. dopamine stimulated pde activity and an 'inhibitory' factor was found in glands obtained from rapidly engorging ticks which decreased pde activity. these findings are discussed as they relate to the process of fluid secretion by ...1978212286
a review of the evidence in retrospect for a rickettsial etiology in bullis fever.the authors have presented evidence through work done 25-30 years ago for the rickettsial etiology of bullis fever, a forgotten epidemic which occurred with over a 1,000 cases among world war ii troops in training at camp bullis, texas. rickettsiae were recovered from blood and lymph nodes of patients and from ticks, amblyomma americanum, collected in the area. all patients gave a history of tick-bites. the human and tick strains of rickettsiae, carried in chick embryo culture and in animal pass ...19751103350
tick (acari: ixodidae) attachment cement and salivary gland cells contain similar immunoreactive polypeptides.a specific antiserum (12c) raised to a 90-kda immunogenic component of salivary glands of the tick rhipicephalus appendiculatus recognized similar 90-kda polypeptides from salivary glands of the american dog tick, dermacentor variabilis, and the lone star tick, amblyomma americanum, as well as 70-kda polypeptides in the cement of d. variabilis, a. americanum, and r. sanguineus (brown dog tick). the reduction in size of the polypeptide for these ticks suggests that it is modified in some way duri ...19921495047
tick sweep: modification of the tick drag-flag method for sampling nymphs of the deer tick (acari: ixodidae).we describe a version of the standard tick drag-flag modified for use in close-growing and tangled vegetation, as well as under ornamental shrubbery and fallen branches. two major features of the sweep are: (1) it allows the user to remain upright with the flag parallel to the ground, thus sampling effectively beneath low and fallen branches and around shrubs, as well as capturing host-seeking ticks in advance of the operator; and (2) the use of a flannel rubberized-laminate fabric (crib sheet) ...19921495058
field evaluation of two formulations of cyfluthrin for control of ixodes dammini and amblyomma americanum (acari: ixodidae).liquid or granular cyfluthrin was applied in the spring and fall to different test plots at a rate of 0.41 (ai) kg/ha to control ixodes dammini spielman, clifford, piesman & corwin and amblyomma americanum (l.). spring application of liquid cyfluthrin showed the most significant decreases of both species. i. dammini nymphs were reduced 97% at 10 d, 100% at 2 mo, and 100% at 1 yr; and a. americanum adults and nymphs were reduced 91-93% at 10 d and 100% at 2 mo posttreatment. granular cyfluthrin a ...19921495073
borrelia sp. in ticks recovered from white-tailed deer in alabama.six hundred sixty-five hunter-killed white-tailed deer (odocoileus virginianus) from 18 counties in alabama (usa) were examined for ticks. most of the collections were made at state-operated wildlife management areas. four species of ticks (n = 4,527) were recovered: the lone star tick amblyomma americanum (n = 482); the gulf coast tick a. maculatum (n = 11); the winter tick dermacentor albipictus (n = 1,242); and the black-legged tick ixodes scapularis (n = 2,792). fifty-six percent of the tick ...19921512879
monthly incidence of theileria cervi and seroconversion to babesia odocoilei in white-tailed deer (odocoileus virginianus) in texas.monthly monitoring of fawns collected from an area in texas endemic for theileria cervi and babesia odocoilei showed that transmission of t. cervi occurred during july and august, a time period consistent with the occurrence of amblyomma americanum. seroconversion to b. odocoilei occurred during october to december and possibly continued through january and february. the time of seroconversion was more suggestive of transmission of b. odocoilei by ixodes scapularis than by amblyomma americanum.19921512881
the ecology and behavior of the lone star tick (acarina: ixodidae). vi. response of unfed adults to certain environmental parameters. 19751223301
the ecology and behavior of the lone star tick (acarina: ixodidae). vii. pre- and post-molt behavior of engorged nymphs and larvae. 19751223302
parasites of cottontail rabbits of southern illinois.fifteen species of parasites including haemaphysalis leporispalustris, ixodes dentatus, amblyomma americanum, cediopsylla simplex, odontopsyllus multispinosus, cuterebra sp., obeliscoides cuniculi, trichostrongylus calcaratus, trichostrongylus affinis, longistriata noviberiae, dermatoxys veligera, trichuris sp., mosgovoyia sp., taenia pisiformis, and hasstilesia tricolor as well as coccidia oocysts were collected from 96 cottontail rabbits (sylvilagus floridanus) confined to a pen in southern il ...19921491303
quantitative evaluation of sampling methods for ixodes dammini and amblyomma americanum (acari: ixodidae).three tick-sampling methods (dry ice-baited tick traps, cloth drags, and ambulatory human host) were evaluated to determine which technique yielded the greatest capture of host-seeking stages of ixodes dammini spielman, clifford, piesman & corwin and amblyomma americanum (l.). the most reliable method, catching more stages and significantly more numbers of i. dammini and a. americanum; was dry ice-baited tick traps. there were no significant differences between the drag and human-host methods fo ...19921625293
inability of ixodes cookei and amblyomma americanum nymphs (acari: ixodidae) to transmit borrelia burgdorferi.the vector competency of ixodes cookei packard and amblyomma americanum (l.) for borrelia burgdorferi was studied using syrian hamsters. ixodes dammini spielman, clifford, piesman & corwin were used as controls. darkfield and immunofluorescent examinations of midgut diverticula revealed b. burgdorferi spirochetes in 32 of 36 (88.9%) i. dammini larvae, 5 of 36 (13.9%) i. cookei larvae, and 7 of 36 (19.4%) a. americanum larvae within 48 h after feeding on infected syrian hamsters. b. burgdorferi w ...19921625302
oral secretion elicited by effectors of signal transduction pathways in the salivary glands of amblyomma americanum (acari: ixodidae).the abilities of various effectors of signal pathways in tick salivary glands to stimulate oral secretions in partially fed amblyomma americanum (l.) female ticks were compared. pilocarpine stimulated secretion the most rapidly following tick stimulation, but its effectiveness declined with time and subsequent injections. secretion rates induced by dopamine and theophylline increased with time of collection and additional injections and were as effective as pilocarpine after 60 min. activators o ...19921552527
distribution, density, and lyme disease spirochete infection in ixodes dammini (acari: ixodidae) on white-tailed deer in maryland.a statewide survey of ticks parasitizing white-tailed deer was carried out in maryland during november 1989 to assess the status of the deer tick, ixodes dammini spielman, clifford, piesman & corwin, the major vector of lyme disease in the northeastern united states. ticks were collected from deer carcasses brought in by hunters at 23 check stations (one per county). a total of 3,437 i. dammini were collected from 538 of 1,281 deer (42%), together with 2,013 dermacentor albipictus (packard) and ...19921552529
amblyomma americanum: characterization of salivary prostaglandins e2 and f2 alpha by rp-hplc/bioassay and gas chromatography-mass spectrometry.secretagogue-induced saliva of the tick, amblyomma americanum (l.) was fractionated by reversed-phase-high-performance liquid chromatography (rp-hplc) and bioassayed in smooth muscle preparations. material with retention times of authentic prostaglandin e2 (pge2) and prostaglandin f2 alpha (pgf2 alpha) were found to cause contraction of preparations of rat colon and rat stomach strips. gas chromatography-mass spectra of selected ions of both hplc-purified fractions confirmed the existence of pge ...19921730268
tick infestations of white-tailed deer in alabama.four species of ticks were collected from 537 white-tailed deer (odocoileus virginianus), examined during the hunting seasons (november to january) of 1988-89 and 1989-90 at selected locations in alabama (usa). ixodes scapularis was the most common tick recovered (2,060 specimens) and infested 54% of the deer. dermacentor albipictus was the second most frequent tick (1,253 specimens) and infested 15% of the deer. amblyomma americanum was the third most frequent tick (315 specimens) and infested ...19911758026
effect of ivermectin on the volume of blood ingested by two species of ticks (acari: ixodidae) feeding on cattle.females of the lone star tick, amblyomma americanum (l.), and the american dog tick, dermacentor variabilis (say), were fed on ivermectin (ivomec)-treated and untreated bovines to determine the effect of the acaricide on volume of blood ingested and to compare the weight differences between the treatment and control groups at various time intervals after attachment. adult females from each genus were collected from bos tarus hosts and subjected to hematin assays on three collection dates to esti ...19911875376
manifestations of immunity in sheep repeatedly infested with amblyomma americanum ticks.three sheep were infested 4 times with 100 amblyomma americanum tick pairs and kept indoors until the natural termination of the infestations. characteristics of the tick populations that show efficiency of feeding, fertility, and offspring development, and elisa antibodies to tick salivary gland extracts were studied at each infestation. on average, female ticks fed on tick-naive sheep detached at 12.1 +/- 0.2 (mean +/- standard error) days, weighed 492 +/- 16.8 mg, engorged 40.7 mg per day, an ...19911919917
antigens of amblyomma americanum ticks recognized by repeatedly infested sheep.sera were taken from 3 sheep that had been infested 5 times with amblyomma americanum and that exhibited manifestations of humoral depression to homologous antigens and anti-tick resistance. proteins extracted from the intestine or salivary glands of unfed ticks or salivary glands from partially (3-day) fed ticks were analyzed by polyacrylamide gel electrophoresis (page) and sodium dodecyl sulfate-page. antigens recognized by the sheep in the same materials before and after each infestation were ...19911919918
selective breeding for photoperiodically induced developmental diapause in laboratory strains of amblyomma americanum (acari: ixodidae).offspring of amblyomma americanum (l.) reared for four generations in a 12:12 (l:d) photoperiod in the laboratory were held in 10:14 (l:d) conditions and bred to select for developmental diapause (dia) or nondiapause (non) characteristics for two additional generations. sequential generations of fed dia nymphs had mean molting times (days from detachment to ecdysis) that were 8.0% (dia1) and 35.7% (dia2) greater than parental ticks, and maximal development time was extended by 20% in dia2 ticks ...19911941917
mechanisms of host-tick contact with special reference to amblyomma americanum (acari: ixodidae) in beef cattle forage least five groups of parameters regulate contact between ticks and host animals. group 1 (seasonal effects) and group 2 (daily effects) comprise abiotic parameters and include daylength, temperature, relative humidity, and interactions thereof. groups 3, 4, and 5 consist of biotic parameters. these pertain to biological processes in ticks (group 3), such as hunger responses and spatial patterns in aphagous tick populations; biological processes in host animals (group 4), such as patterns of h ...19911941920
etiologic agent of lyme disease, borrelia burgdorferi, detected in ticks (acari: ixodidae) collected at a focus in alabama.the study was conducted at sites of known transmission of borrelia burgdorferi in east central alabama. the objectives were to determine species of ticks present at these sites, their host associations, and species of ticks and small mammals naturally infected with b. burgdorferi. a total of 451 hosts were examined for ticks, including cotton mice, peromyscus gossypinus (le conte); cotton rats, sigmodon hispidus say & ord; southern short-tailed shrews, blarina carolinensis (bachman); house mice, ...19911941933
putative new expression of genes in ixodid tick salivary gland development during feeding.poly(a+) mrna-enriched fractions from salivary glands of partially fed amblyomma americanum female ticks were translated in vitro with a rabbit reticulocyte translation system. translated proteins were labeled with [35s]methionine, separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis, and identified by autoradiography. thirty major identifiable polypeptides with molecular weights ranging from 14 to 136 kda were synthesized from mrna isolated from salivary glands of ticks weighi ...19911710268
tick information sheet. the lone star tick. amblyomma americanum. 19912014616
ehrlichiosis in children.tick-borne rickettsiae of the genus ehrlichia have recently been recognized as a cause of human illness in the united states. in the years 1986-1988, 10 cases of ehrlichiosis were diagnosed in children in oklahoma. fever and headache were universal: myalgias, nausea, vomiting, and anorexia were also common. rash was observed in six patients but was a prominent finding in only one. leukopenia, lymphopenia, and thrombocytopenia were common laboratory abnormalities. six patients were treated with t ...19911987531
management of lone star ticks (acari: ixodidae) in recreational areas with acaricide applications, vegetative management, and exclusion of white-tailed deer.a project on management of lone star ticks, amblyomma americanum (l.), at land between the lakes, a tennessee valley authority recreational area in kentucky-tennessee, during 1984-1988, demonstrated the effectiveness and economics of three control technologies. acaricide applications (chlorpyrifos at 0.28 kg [ai]/ha), vegetative management (mowing and removal of 40% overstory and 90-100% of midstory, understory, and leaf litter), and host management (white-tailed deer exclusion from a 71-ha camp ...19901696994
further investigations on the action of ecdysteroids on the salivary glands of the female tick amblyomma americanum.two phytecdysteroids (abutasterone, makisterone a) and five synthetic ecdysteroid analogues, all at 1 microgram/ml, were tested on salivary glands from the female tick, amblyomma americanum l. (acari:ixodidae), held in organ culture for four days. all of these substances caused a significant reduction in fluid secretory competence of salivary glands in vitro. this constitutes further evidence that the structural requirements for causing salivary-gland degeneration in ticks are similar to those g ...19912044433
cattle breed alters reproduction in amblyomma americanum (acari: ixodidae).female amblyomma americanum [l.] that feed on bos taurus cattle weigh significantly (p = 0.05) more (mean = 505.4 mg) than females that feed on b. indicus x b. taurus cattle (mean = 450.7 mg) but not females that feed on b. indicus cattle (mean = 489.7 mg). females that feed on b. taurus cattle lay more eggs (mean = 3492) and produce more larvae (mean = 3243) than females that feed on b. indicus cattle (mean = 3103 eggs; 2925 larvae) or b. indicus x b. taurus cattle (mean = 2961 eggs; 2759 larva ...19902081445
comparative efficiency of flagging and carbon dioxide-baited sticky traps for collecting the lone star tick, amblyomma americanum (acarina: ixodidae).collections of amblyomma americanum (l.) from five habitat types showed that significantly more ticks of all life stages could be collected by co2-baited sticky traps than by the standard flagging technique. the effect of habitat type and season significantly influenced the number of ticks collected by both techniques. traps baited with carbon dioxide revealed adult tick activity in several habitats several weeks earlier than did flagging, because flagging failed to efficiently recover ticks unl ...19902231613
comparative field evaluation of permethrin and deet-treated military uniforms for personal protection against ticks (acari).the effectiveness of permethrin-impregnated (pi) versus permethrin-sprayed (ps) military battle dress uniforms was evaluated in protecting soldiers from tick bite. at the same time, an extended-duration formulation of n,n-diethyl-m-toluamide (deet), when applied to clothing only, was evaluated and compared with the permethrin-treated uniforms. testing consisted of exposing subjects, clothed in either untreated or the variously treated uniforms, to field populations of ticks during a series of 30 ...19902231620
geographic occurrence of ixodes scapularis and amblyomma americanum (acari: ixodidae) infesting white-tailed deer in north carolina.a state-wide survey to determine the occurrence and comparative numbers of ticks infecting white-tailed deer (odocoileus virginianus) was conducted in north carolina (usa). one thousand six hundred twenty nine deer were examined in 60 of 100 counties; with the exception of one county in the piedmont region, all tick-infested deer occurred in the coastal plain. ixodes scapularis (46%) and amblyomma americanum (53%) were the most prevalent species encountered and accounted for more than 98% of the ...19902250335
amblyomma americanum (l.): protein kinase c-independent fluid secretion by isolated salivary glands.protein kinase c activity was partially purified from tick salivary glands by fast protein liquid chromatography anion-exchange chromatography. enzyme activity was stimulated by ca2+, phosphatidylserine, and diacylglycerol with the highest activity observed in the presence of all three modulators. enzyme activity was inhibited by a synthetic pseudosubstrate peptide with an amino acid sequence resembling the protein kinase c substrate phosphorylation site. the protein kinase c activator, 1-oleoyl ...19921582485
experimental transmission of a granulocytic form of the tribe ehrlichieae by dermacentor variabilis and amblyomma americanum to dogs.transstadial transmission of granulocytic ehrlichieae in dogs was attempted using ticks, amblyomma americanum and dermacentor variabilis. ticks were exposed by feeding as nymphs on acutely infected pups; adult ticks then fed to repletion on susceptible adult dogs that were monitored daily for signs of infection. evidence of transmission was not observed in control dogs or in those exposed to d variabilis. in contrast, dogs exposed to a americanum developed serologic or clinical evidence of infec ...19902368951
rickettsia in texas.since the first reported case in 1941, rocky mountain spotted fever in humans has been reported from many areas of texas, with two major foci, one located in the north-central region and the other in the eastern region of the state. during the period 1979-1988, 421 cases of rmsf were reported, reaching 108 cases in 1983 and declining in subsequent years. statewide surveillance programs to detect spotted fever group rickettsiae in tick populations were initiated in 1976. in recent years, the sfg ...19902378448
hyperosmotic oral fluid secretion during active water vapour absorption and during desiccation-induced storage-excretion by the unfed female tick amblyomma americanum. 19912061709
effects of sequential infestations of dermacentor albipictus and amblyomma americanum (acari: ixodidae) on overwintering beef cows in west-central texas.infestations of winter ticks, dermacentor albipictus (packard), observed on mature black angus cows, reached peak levels in january and diminished through march. infestations of adult lone star ticks, amblyomma americanum (l.), began in mid-january and increased through may. cows receiving ectrin, taktic, or deltox treatments on 13 december and 21 february experienced significantly less weight loss and entered the subsequent breeding season with higher average body weight than untreated cows. in ...19902388237
intrinsic competence of three ixodid ticks (acari) as vectors of the lyme disease spirochete.we compared the intrinsic vector competence of ixodes dammini spielman et al., dermacentor variabilis (say), and amblyomma americanum (l.) for the lyme disease spirochete (borrelia burgdorferi johnson et al.) on prudence island, rhode island, a lyme disease-endemic site where all three ticks occur together. natural and experimental spirochete infection rates were determined in those ticks and their degree of contact with white-footed mice (peromyscus leucopus), the principal reservoir host, was ...19902388239
western blot analysis of amblyomma americanum-derived stage-specific and shared antigens using serum from guinea pigs expressing resistance.serum from guinea pigs expressing resistance to larval, nymphal and adult amblyomma americanum ticks was used in western blot analyses to identify potential antigens from egg, larval and nymphal, and female salivary gland extract preparations. the results demonstrate multiple antigens unique to each life stage, as well as several shared proteins between the three life stages. however, it appears as if two particular proteins of 25 and 38 kda may be more important than others, based upon their pr ...19882455376
experimental infection of six species of ixodid ticks with dugbe virus (family bunyaviridae, genus nairovirus).the vector potential of each of 6 species of colonized north american and african ixodid ticks was assessed by intracoelomic inoculation with dugbe virus (ibar 1792, 14th passage in suckling mouse brain) and viral titers were monitored after selected incubation periods. persistence of dugbe virus for greater than or equal to 53 days in 5 species (dermacentor andersoni, d. variabilis, amblyomma americanum, rhipicephalus appendiculatus, and r. sanguineus) indicates that infection occurred. viral t ...19892496609
sites of attachment and density assessment in amblyomma americanum (acari: ixodidae) on nursing beef calves.primary attachment sites of male, female, and nymphal amblyomma americanum (l.) on nursing beef calves were the axillary, inguinal and perianal areas of the body. about 50% of all larvae fed on the ears. a density assessment method which uses the number of a. americanum on less than or equal to 5 body areas to predict the total number of ticks (tick burden) on the left side of a calf is presented. estimates of tick burden for male, female, nymphal and larval a. americanum each require examinatio ...19892714123
isolation of borrelia burgdorferi from arthropods collected in texas.the texas department of health laboratory cultured arthropods from november 1988 through december 1989 in an attempt to isolate borrelia burgdorferi, the etiologic agent of lyme disease. spirochetes were isolated from eight of 1,093 pools of arthropods cultured. the spirochetal isolates were from several tick and one flea species, including amblyomma americanum, a. maculatum, ixodes scapularis, and ctenocephalides felis. these 8 isolates reacted specifically when treated with monoclonal antibodi ...19912063950
amblyomma americanum: identification of tick salivary gland antigens from unfed and early feeding females with comparisons to ixodes dammini and dermacentor variabilis.salivary gland antigens involved in host resistance to tick feeding by amblyomma americanum (lone star tick) have been identified. gland extracts from unfed and partially fed 12-, 48-, 72-, 96-, and 120-hr females and their corresponding midgut tissues were analyzed by immunoblotting with sera from naturally immune and hyperimmune sheep and rabbits. polypeptides at 90, 75, 58, 45, 33, and 23 kda from the salivary glands of a. americanum females were consistently observed with antibodies from bot ...19902298277
female mediation of feeding time on cattle in adult lone star ticks (acari: ixodidae).the extended feeding time response on cattle of adult lone star ticks, amblyomma americanum (l.), during november through december is facultative and is mediated by the female. mean feeding time (11.8 d) in female ticks taken from the field and held at 14:10 (l:d) photoperiod and 25 degrees c for greater than or equal to 15 d was significantly shorter (p = 0.05) than for females taken directly from the field and fed on cattle (14.6 d). mean feeding times of females from the field paired to males ...19892769719
reduction of the amblyomma americanum (acari: ixodidae) population at fort a.p. hill, virginia, by aerial application of diazinon granules: correlation of percentage control with received dose.habitat (280 ha) of lone star tick, amblyomma americanum (l.), was aerially treated with 14% diazinon granules. concentration of acaricide reaching the forest floor ranged from 0.02 to 1.25 kg (ai)/ha. greater than 85% control was achieved at study plots receiving the highest dose. a positive correlation was shown between dose received at the forest floor and percentage of control of adults (r = 0.91) and nymphs (r = 0.86).19892795622
habitat use by cattle affects host contact with lone star ticks (acari: ixodidae).the location of zebu, british, and zebu x british cattle in tick-infested plots from march through september 1986 was compared with the location of amblyomma americanum l. in the same plots. in april, may, and june, zebu cattle spent less time (9.3-19.4%) in tick-infested quadrats than british (44.4-63.9%) or zebu-british (49.0-69.3%) cattle. in the same months, the probability that a. americanum would contact zebu cattle (1.5-19.6%) was significantly lower than for british (34.7-41.7%) or zebu- ...19892754101
ectoparasitic and phoretic arthropods of virginia opossums (didelphis virginiana) in central tennessee.thirteen species of ectoparasitic (12) or phoretic (1) arthropods were collected from 26 adult virginia opossums, didelphis virginiana, live-trapped from april through september 1987 in davidson county, tennessee. the cat flea ctenocephalides felis and the american dog tick dermacentor variabilis were the predominant species with respect to mean intensity and prevalence. the macronyssid mite ornithonyssus wernecki and the atopomelid mite didelphilichus serrifer, both specific parasites of this h ...19902380870
polyfluoro 1,3-diketones as systemic insecticides.a series of aryl polyfluoro 1,3-diketones were examined for systemic ectoparasiticidal activity in cattle. the compounds demonstrated efficacy against several economically important species of insects and acarina. at dosages of 5 mg/kg x1 or 0.35 mg/kg per day intraruminally, activity was observed against blowfly larvae (phormia regina), adult stable fly (stomoxys calcitrans), and lone star tick (amblyomma americanum). in vivo activity was not directly related to in vitro activity, showing a str ...19892769686
effect of age on cholinesterase activity and protein of unfed larval ticks.the cholinesterase (ache) activity and total protein in homogenates of unfed larvae of amblyomma americanum (l.), a. cajennense (fabricius), a. maculatum koch, anocentor nitens neumann, and boophilus microplus (canestrini) were determined weekly in ticks 1-6 wk of age. there was a considerable variation in total protein, ache, and the ratio of ache to protein as the ticks aged. however, ache activities were constant or increased with age and total protein levels were constant or decreased. no di ...19892918444
failure to detect infection in fallow deer (cervus dama) exposed to theileria cervi from white-tailed deer.a frozen stabilate was produced from theileria cervi sporozoites in salivary glands of adult amblyomma americanum. the stabilate was inoculated into three fallow deer (cervus dama) and two white-tailed deer (odocoileus virginianus). following inoculation, the white-tailed deer developed parasitemias as determined by blood smear examination at 11 and 13 days postexposure. repeat examination of blood from the three fallow deer for 30 days postexposure failed to reveal observable piro-plasms. these ...19873119873
rejection of ticks from guinea pigs by anti-hapten-antibody-mediated degranulation of basophils at cutaneous basophil hypersensitivity sites: role of mediators other than histamine.previous studies have established that recruitment of basophils to sites of tick feeding in guinea pigs is required to effect immune resistance. in the current study, actively sensitized guinea pigs treated three times daily with h-1 (mepyramine) and h-2 (cimetidine) histamine receptor antagonists, during the challenge tick infestation period, expressed normal resistance to amblyomma americanum larvae. similarly, naive guinea pigs treated with anti-histamines four times daily, beginning 7 days b ...19852578152
the ultrastructure of sporogony in theileria cervi (bettencourt et al., 1907) in salivary glands of female amblyomma americanum (l.) ticks.the process of sporogony of theileria cervi in salivary glands of unfed and feeding amblyomma americanum females that were infected as nymphs was studied by light and electron microscopy (sem and tem). sporogony was observed only in granular acini type iii and in cells classified as complex granular. infected acini in salivary glands of both unfed and feeding ticks were enlarged. some stages of parasite development were evident with light microscopy and sem, but the specific events of sporogony ...19873125313
control of lone star ticks (acari: ixodidae) on spanish goats and white-tailed deer with orally administered ivermectin.ivermectin administered orally to spanish goats, capra hircus (l.), or to white-tailed deer, odocoileus virginianus (zimmerman), was highly effective against lone star ticks, amblyomma americanum (l.). for spanish goats, daily oral doses of 20 micrograms/kg resulted in greater than or equal to 2 ppb ivermectin in the blood. this level was sufficient to cause greater than 95% reduction of estimated larvae from feeding ticks. a bioassay with horn flies, haematobia irritans (l.), was developed to e ...19892607030
ability to ixodes scapularis, dermacentor variabilis, and amblyomma americanum (acari: ixodidae) to acquire, maintain, and transmit lyme disease spirochetes (borrelia burgdorferi). 19883193425
role of small mammals in population dynamics and dissemination of amblyomma americanum and dermacentor variabilis (acari: ixodidae) at land between the lakes, tennessee. 19873295243
characterization of tick antigens inducing host immune resistance. ii. description of rabbit-acquired immunity to amblyomma americanum ticks and identification of potential tick antigens by western blot analysis.feeding by adult amblyomma americanum ticks induced a level of immunity in rabbits to subsequent tick feeding that resulted in a significant decrease in tick feeding success and fecundity. histological analysis of tick feeding sites in hosts expressing resistance revealed a predominant eosinophil response, with weak basophil and neutrophil infiltrates. while the basophil was never the dominant granulocyte at the tick feeding sites in resistant hosts, this cell exhibited the greatest increase in ...19883291384
medium-sized mammal hosts of amblyomma americanum and dermacentor variabilis (acari: ixodidae) at land between the lakes, tennessee, and effects of integrated tick management on host infestations. 19883204625
effects of photoperiod on nymphal diapause in amblyomma americanum (acari: ixodidae). 19883204627
the effect of avermectins on feeding, salivary fluid secretion, and fecundity in some ixodid ticks.we tested the effects of the potent acaricides, avermectin b1a (avm) and 22,23-dihydroavermectin b1 (ivermectin; ivm) when injected directly into partially fed and fully engorged female ticks. when injected into small ticks (amblyomma hebraeum koch), neither drug (up to 100 micrograms/kg b.w.) inhibited subsequent engorgement nor affected oviposition latency, weight of total egg mass laid nor viability of laid eggs. at higher concentrations (1000 and 5000 micrograms/kg b.w.), avm and ivm were ma ...19863451859
attempted transmission of ehrlichia risticii, causative agent of potomac horse fever, by the ticks, dermacentor variabilis, rhipicephalus sanguineus, ixodes scapularis and amblyomma americanum.dermacentor variabilis, rhipicephalus sanguineus, amblyomma americanum, and ixodes scapularis ticks were investigated for their ability to transmit potomac horse fever. larval and nymphal ticks were exposed to ehrlichia risticii by feeding on mice inoculated with the organism. molted exposed ticks were then allowed to feed on susceptible ponies or mice. no evidence of transmission, either clinically or by detection of antibodies to e. risticii in mice or ponies, was observed for any tick species ...19902307070
[the taxonomic aspects of the transmission of the causative agent of lyme disease].according to world literature data 17 species of ixodid ticks have been studied for natural infection with the lyme disease agent. analysis of the data on the level of the infection, transovarial and transphase transmission has shown that main biological vectors of borrelia burgdorferi are the species of the subgenus ixodes s. str. - i. ricinus, i. persulcatus (eurasia), i. dammini, i. pacificus (north america). potential vectors are i. scapularis, i. dentatus, amblyomma americanum, dermacentor ...19902259524
horizontal movement of adult ixodes dammini (acari: ixodidae) attracted to co2-baited traps.the ability of male and female deer ticks, ixodes dammini spielman, clifford, piesman, & corwin, to move horizontally was evaluated by performing a mark-recapture study. in each of two experiments, 120 ticks were marked with fluorescent powder and released at predetermined distances from a co2-baited trap. the mean recruitment distance was 1.8 m after 6 d of trap operation. this distance is appreciably lower than those calculated from previous studies of several other species of ixodid ticks, in ...19911941943
estimation and economic implications of lone star tick (acari: ixodidae) infestation on weight gain of cattle, bos taurus and bos taurus x bos indicus. 19873584640
effects of gamma radiation on spermatogenesis and fertility of male amblyomma americanum (acari: ixodidae).amblyomma americanum males were treated with 0.5, 1, 2, 3, 4, 8, and 16 krad of gamma radiation. testes of ticks treated with 2, 3, 4, 8, and 16 krad were smaller than those of ticks irradiated at lower levels and controls. no recognizable alteration in timing of spermatogenesis was noted among the different radiation groups, but severe breakdown and depletion of germinal cells was noted at 4, 8, and 16 krad. percent hatch of larvae from crosses of irradiated males and untreated females decrease ...19873585625
computer simulation of population dynamics of the lone star tick, amblyomma americanum (acari: ixodidae). 19873585931
effects of season and area on ectoparasites of white-tailed deer (odocoileus virginianus) in mississippi.nine species of ectoparasites (4 acari, 2 mallophaga, 1 anoplura, 1 diptera, and 1 siphonaptera) were recovered from 126 white-tailed deer collected in northern, central, and southern mississippi. intensity and prevalence of adults of ixodes scapularis and larvae, nymphs, and adults of amblyomma americanum varied significantly over collection periods, but not between host sexes. lipoptena mazamae occurred on deer from only one study area. although individual deer were heavily parasitized by tric ...19873586204
increased population densities of amblyomma americanum (acari: ixodidae) on long island, new york.lone star ticks, amblyomma americanum comprised a significantly greater proportion of total ticks flagged on eastern long island and fire island, new york, in 1986 and 1990 than in samples reported by other authors from the 1940s (when a. americanum was not collected by flagging or from hosts) and the 1970s. therefore, population densities of a. americanum apparently have increased in recent years on southeastern long island, where this species now is distributed widely.19912040963
computer simulation of area-wide management strategies for the lone star tick, amblyomma americanum (acari: ixodidae). 19873669024
population growth rates for amblyomma americanum (acari: ixodidae) on bos indicus, b. taurus and b. indicus x b. taurus cattle.densities of amblyomma americanum (l.) on bos indicus, b. taurus and b. indicus x b. taurus cattle are compared over a 3-year period, and the growth rate (rate of increase or decrease) of parasitic tick populations on each cattle genotype is estimated. average log10 densities of parasitic a. americanum larvae are significantly (p = 0.05) lower on b. indicus cattle than on b. taurus and b. indicus xb. taurus cattle. average log densities of nymphal and adult ticks on b. taurus cattle are signific ...19902261818
borrelia burgdorferi in ticks (acari: ixodidae) from coastal virginia.ixodid ticks removed from hosts and from vegetation during march-november 1987 at sites in coastal virginia and north carolina were examined for borrelia burgdorferi. b. burgdorferi was evident in nine (22%) ixodes cookei packard removed from rice rats (oryzomys palustris), a white-footed mouse (peromyscus leucopus), and raccoons (procyon lotor); four (6%) amblyomma americanum (l.) removed from raccoons; and two (3%) dermacentor variabilis (say) removed from a raccoon and a rice rat. b. burgdorf ...19911941936
spotted fever group rickettsiae in the lone star tick, amblyomma americanum (acari: ixodidae). 19863772952
survival of the lone star tick (acari: ixodidae) under flooding conditions: a laboratory evaluation. 19863805482
a seed tick infestation of the conjunctiva: amblyomma americanum larva.ticks commonly infest humans but rarely bite the eyes. they are vectors of disease; therefore, rapid and complete removal is important. their attachment can be so secure that removal is difficult or hazardous. we excised a larval form of amblyomma americanum from a woodsman's conjunctiva.19873566026
rickettsia-like organisms in ticks and antibodies to spotted fever-group rickettsiae in mammals from northern mississippi.studies were conducted from april through august during 1974 and 1975 on 30 randomly selected trapping sites in wall doxey state park, holly springs national forest, and 1.6 km south of the park in marshall county, mississippi to provide information on the occurrence of ticks involved in the maintenance and transmission of spotted fever-group rickettsiae in nature. of 365 animals (14 species) collected, 186 (51%) were parasitized by 4,169 ticks. species of ticks collected included: dermacentor v ...19853923212
the development of amblyomma americanum and dermacentor variabilis (acari: ixodidae) fed on rabbits immunized with tick hemolymph.the possibility of interfering with the normal function of tick hemolymph using antihemolymph antibodies taken in with the bloodmeal, was investigated. cell free hemolymph from replete amblyomma americanum and dermacentor variabilis ticks was used to immunize rabbits. immunized rabbits developed high antihemolymph antibody titers (ca. 10(5)) and had no ill side effects. rabbits were simultaneously infested with larvae, nymphs, and adult ticks. the biological performance of ticks fed on immunized ...19873588587
production system-based model for defining economic thresholds in preweaner beef cattle, bos taurus, infested with the lone star tick, amblyomma americanum (acari: ixodidae). 19863950186
intradermal infestation of a red fox (vulpes vulpes) by the lone star tick (amblyomma americanum). 19863951048
physiological and biochemical changes in unfed lone star ticks, amblyomma americanum (acari: ixodidae), with increasing age. 19863735326
field method for evaluating the effectiveness of acaricides against lone star ticks (acari: ixodidae) on domestic dogs. 19853973208
apparatus for artificial infestation of pastured beef cattle with the lone star tick (acari: ixodidae). 19853998270
serum basophil-stimulating activity in the guinea-pig during induction of basophilic responses to ovalbumin and tick feeding.we have described functional and biochemical characteristics of a distinct t-cell dependent guinea-pig basophil-stimulating factor (bsf), measured using a sensitive 7-day bone marrow culture assay, standardized with high-activity bsf present in serum-free splenic cell-conditioned medium (cm). in the present studies, the in vivo relevance of bsf was explored during protocols of induction of peripheral blood or tissue basophil responses to ovalbumin (oa) injection or amblyomma americanum tick feed ...19863733145
systemic activity of closantel for control of lone star ticks, amblyomma americanum (l.), on cattle.cattle were treated once at 5 mg/kg orally or subcutaneously or daily at 0.1-5 mg/kg orally or 0.1-1 mg/kg subcutaneously with closantel, n-[5-chloro-4-[(4-chlorophenyl)cyanomethyl]-2-methylphenyl]-2-hydroxy-3, 5-diiodobenzamide, and numbers and weights of engorged females, weights of egg masses and hatch of eggs of lone star ticks, amblyomma americanum, were recorded. effectiveness of treatments on reproduction was determined by comparing total estimated larvae (el) (el = wt. egg mass x est. % ...19853870959
density perturbation in populations of amblyomma americanum (acari: ixodidae) in beef cattle forage areas in response to two regimens of vegetation management. 19863950182
amblyomma americanum: physiochemical isolation of a protein derived from the tick salivary gland that is capable of inducing immune resistance in guinea pigs.crude salivary gland derived proteins from amblyomma americanum ticks were analyzed by physiochemical (gel filtration and ion exchange chromatography) and immunochemical guinea pig igg1 (anti-tick immunoaffinity column) techniques for the presence of antigens responsible for the induction of host immune resistance responses. gel filtration (g-75 sephadex) and ion exchange (diethyl aminoethyl cellulose) chromatography of crude salivary gland antigen yielded multiple fractions, but only one fracti ...19863720900
influence of deer exclusion on populations of lone star ticks and american dog ticks (acari: ixodidae). 19863722591
surveillance of lyme disease in the united states, 1982.lyme disease is a tick-borne illness that has been reported from three regions in the united states--the northeast, midwest, and west--which correspond to the distribution of the recognized vectors of the disease, ixodes dammini and ixodes pacificus. in 1982, a surveillance system designed to define the morbidity and geographic distribution for lyme disease by using a clinical case definition received information on 491 definite cases and 38 probable cases. of the definite cases, 489 were acquir ...19853998509
amblyomma americanum: requirement for host fc receptors in antibody-mediated acquired immune resistance to ticks.guinea pig recipients of anti-tick immune serum or immune peritoneal exudate cells expressed 25 and 30% tick rejection, respectively, when challenged with amblyomma americanum larval ticks. previous studies have shown that igg1 antibodies are responsible for the ability of immune serum to transfer resistance to ticks and to mediate the accompanying, and required, cutaneous basophil response. since igg1 antibodies induce mast cell-mediated passive cutaneous anaphylaxis and cutaneous basophil resp ...19853972060
weight changes in individual feeding amblyomma americanum female ticks. 19854093818
ectoparasites of the blackbuck antelope (antilope cervicapra).fifty-two free-ranging blackbuck antelope (antilope cervicapra) from texas were examined for ectoparasites. two species of sucking lice (anoplura), one species of chewing louse (mallophaga), one species of louse fly (diptera), and three species of ticks (acari) were found. this is the first report of the anoplurans linognathus cervicaprae and l. pithodes from the western hemisphere. the southern deer ked (lipoptena mazamae), the winter tick (dermacentor albipictus), and the rabbit tick (haemaphy ...19921512888
attempted transmission of borrelia burgdorferi (spirochaetales: spirochaetaceae) (jdi strain) by ixodes scapularis (acari: ixodidae), dermacentor variabilis, and amblyomma americanum.laboratory-reared ixodes scapularis say, amblyomma americanum (l.), and dermacentor variabilis (say) were fed on new zealand white rabbits experimentally infected with borrelia burgdorferi (jdi strain). at repletion, spirochetes could be detected by dark-field microscopy only in i. scapularis. acquisition rates were 18 and 21%. when previously exposed nymphs of each species were fed on susceptible rabbits, i. scapularis was the only tick of the three species that transmitted b. burgdorferi. when ...19921495078
role of genital sex pheromones in amblyomma americanum and a. maculatum (acari: ixodidae).amblyomma americanum and a. maculatum were studied to determine if genital sex pheromones were present, as reported in dermacentor species. chemical analysis of methanol extracts of the anterior reproductive tracts (source of the genital sex pheromone) of a. americanum and a. maculatum confirmed the presence of the same fatty acids that act as components of the genital sex pheromone in dermacentor variabilis and d. andersoni. in both amblyomma species, removal of the anterior reproductive-tract ...19911860418
human infestation by amblyomma americanum larvae ("seed ticks"). 19854002011
injury thresholds and production loss functions for the lone star tick, amblyomma americanum (acari: ixodidae), on pastured, preweaner beef cattle, bos taurus. 19854056195
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