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serological evidence of infection with ehrlichia spp. in red foxes (vulpes vulpes) in switzerland.serum samples from 1,550 red foxes in switzerland were tested for antibodies to the agents of canine granulocytic and monocytic ehrlichiosis by an indirect immunofluorescent technique. forty-four (2.8%) of the samples were positive for ehrlichia phagocytophila, which is an antigen marker for granulocytic ehrlichiosis. in contrast, none of the samples had antibodies specific to ehrlichia canis, the agent of monocytic ehrlichiosis.199910074544
comparison of ehrlichia muris strains isolated from wild mice and ticks and serologic survey of humans and animals with e. muris as antigen.in metropolitan tokyo, the ehrlichia muris seropositivity rate of 24 wild mice was 63% in hinohara village, but in the surrounding areas, it was 0 to 5%. this finding suggests that the reservoir of e. muris is focal. among the 15 seropositive mice, ehrlichiae were isolated from 9 apodemus speciosus mice and 1 a. argenteus mouse, respectively. five ehrlichial isolates were obtained from 10 ticks (haemaphysalis flava) collected in asuke town, aichi prefecture, where the e. muris type strain had be ...199910074536
[two cases of spotted fever group rickettsiosis contracted in southern parts of africa].a 40-year-old japanese male stayed in zimbabwe and developed a fever above 38 degrees c during which he noted a typical eschar in the lumbar region and also regional inguinal lymphadenopathy. although not conspicuous, erythematous eruptions accompanied by itching were observed on the face, trunk and lower extremities. after returning to japan and visiting our hospital, he was suspected of rickettsiosis and put on minocycline which gradually led to the improvement of the symptoms. immunofluoresce ...19989916419
rickettsia helvetica in ixodes ricinus ticks in sweden.in the present study further characterization of the amplified sequence of the citrate synthase gene of the spotted fever group rickettsia isolated from ixodes ricinus ticks in sweden showed that it has 100% homology with the deposited sequence of the citrate synthase gene of rickettsia helvetica. the restriction fragment length polymorphism (rflp) pattern of an amplified 382-bp product of the citrate synthase sequence, defined by primers rpcs877 and rpcs1258, yielded fragments for our isolate t ...19999889227
experimental transmission of hepatozoon americanum vincent-johnson et al., 1997 to dogs by the gulf coast tick, amblyomma maculatum koch.experimental transmission of hepatozoon americanum to dogs was attempted with four ixodid ticks, viz., rhipicephalus sanguineus, amblyomma americanum, amblyomma maculatum and dermacentor variabilis. ticks that dogs ingested included some that were laboratory-reared and experimentally fed as nymphs on a dog with naturally occurring hepatozoonosis; other ticks were collected as replete or partially engorged larvae, nymphs and adults from dogs that had hepatozoonosis and natural infestations of tic ...19989877066
mitochondrial gene order is not conserved in arthropods: prostriate and metastriate tick mitochondrial genomes.the entire mitochondrial genome was sequenced in a prostriate tick, ixodes hexagonus, and a metastriate tick, rhipicephalus sanguineus. both genomes encode 22 trnas, 13 proteins, and two ribosomal rnas. prostriate ticks are basal members of ixodidae and have the same gene order as limulus polyphemus. in contrast, in r. sanguineus, a block of genes encoding nadh dehydrogenase subunit 1 (nd1), trna(leu)(uur), trna(leu)(cun), 16s rdna, trna(val), 12s rdna, the control region, and the trna(ile) and ...19989866211
[ehrlichia canis infections of dogs in germany. epidemiology, diagnosis, therapy and prophylaxis].between january and december 1997 infections with ehrlichia canis were detected in 211 dogs in germany. of the 53 epidemiologically evaluable dogs, 19 animals born and raised in germany had travelled with their owners abroad in endemic areas, 30 dogs originated from there and four dogs had never left germany. as regards to the possible location of infection it has been registered that most dogs had been taken to countries of the mediterranean sea (spain, france, italy, greece) or had been import ...19989857421
a molecular and serologic survey of ehrlichia canis, e. chaffeensis, and e. ewingii in dogs and ticks from oklahoma.polymerase chain reaction and southern hybridization were used to survey for the presence of ehrlichia canis, ehrlichia chaffeensis, and ehrlichia ewingii in blood samples of 65 dogs that harbored ticks from northcentral and northeastern oklahoma. dog blood samples were also examined for antibodies against e. canis and e. chaffeensis, using an immunofluorescent antibody test. ten of 65 dogs (15.4%) examined were positive for ehrlichia spp. by pcr. four (6.2%) were positive for e. ewingii, 2 (3.1 ...19989831955
seroprevalence of ehrlichia canis and of canine granulocytic ehrlichia infection in dogs in switzerland.serum samples from 996 dogs in switzerland were examined for antibodies to ehrlichia canis and to the agent causing canine granulocytic ehrlichiosis (cge). ehrlichiosis, borreliosis, and systemic illness not associated with ticks were suspected in 75, 122, and 157 of these dogs, respectively. the remainder of the serum samples were obtained from clinically healthy dogs which resided north (n = 235) or south (n = 407) of the alps. the serum samples were tested by an indirect immunofluorescence te ...19989817854
effects of infestation by rhipicephalus sanguineus on lymphocyte blastogenic responses to mitogens in dogs.mitogen blastogenic responses of lymphocytes from dogs infested with adult rhipicephalus sanguineus and the effects of salivary gland extracts (sge) of the tick on the blastogenic responses of lymphocytes from normal dogs were studied. infestation by r. sanguineus significantly suppressed concanavalin a, phyto-hemagglutinin and pokeweed mitogen responses of lymphocytes from dogs. the inhibition of lymphocyte responses of dogs in the first infestation was greater than that in the second infestati ...19989795902
geographic distribution of ticks (acari: ixodidae) in michigan, with emphasis on ixodes scapularis and borrelia burgdorferi.a 12-yr (1985-1996) passive survey in michigan based upon tick submissions from citizens yielded 4,755 ticks of 21 species, 16 of which were probably indigenous in the state. three species of dermacentor [most common, d. variabilis say and d. albipictus (packard)]; 2 species of amblyomma [most common, a. americanum (l.)]; and 12 species of ixodes (most common, i. cookei packard and i. scapularis say), as well as haemaphysalis leporispalustris (packard), rhipicephalus sanguineus latreille, and th ...19989775623
saliva of rhipicephalus sanguineus tick impairs t cell proliferation and ifn-gamma-induced macrophage microbicidal activity.in this study, we investigated tick saliva effects on t cell proliferation, antigen presentation and ifn-gamma-induced macrophage activation, events which are associated with host immune defense mechanisms. mice repeatedly infested with rhipicephalus sanguineus ticks, similarly to dogs, did not develop resistance to further infestations. we determined that r. sanguineus tick saliva inhibited, in a dose-dependent manner, both con-a and specific antigen-induced splenic t cell proliferation. tick s ...19989730222
immune response in rabbits against rhipicephalus sanguineus.rabbits immunised with homogenates of unfed larvae and nymphs of the tick r. sanguineus developed significant level of protective immunity to infestation with all the stages of the species. the acquisition of resistance was based on feeding and developmental performance parameters (rejection, moulting percentages and feeding period) of larvae and nymphs. the acquisition of resistance against adults was also measured by feeding and reproductive performance of female ticks viz., rejection percent, ...19989717464
detection of ehrlichia phagocytophila dna in ixodes ricinus ticks from areas in switzerland where tick-borne fever is endemic.a total of 1,523 adult ixodes ricinus ticks were collected from regions where bovine ehrlichiosis is endemic and were examined for ehrlichia phagocytophila via pcr. of the ticks from cattle with ehrlichiosis, the ticks from healthy cattle, and the free-living ticks, 26.5% (18 of 68), 4.4% (35 of 802), and 0.8% (5 of 653), respectively, were positive.19989705425
interaction of entomopathogenic nematodes (steinernematidae) with selected species of ixodid ticks (acari: ixodidae).entomopathogenic nematodes, currently used for biological control of various insect pests, were tested for their ability to penetrate and kill replete females of several species of ticks including dermacentor variabilis (say), rhipicephalus sanguineus (latreille), amblyomma maculatum koch, and a. cajennense (f.). these species were found to be susceptible to the entomopathogenic nematodes, steinernema feltiae (filipjev) or s. riobravus (cabanillas & poinar), shown in previous studies in our labo ...19989701938
detection of ehrlichia risticii, the agent of potomac horse fever, in freshwater stream snails (pleuroceridae: juga spp.) from northern california.ehrlichia dna was identified by nested pcr in operculate snails (pleuroceridae: juga spp.) collected from stream water in a northern california pasture in which potomac horse fever (phf) is enzootic. sequencing of pcr-amplified dna from a suite of genes (the 16s rrna, groesl heat shock operon, 51-kda major antigen genes) indicated that the source organism closely resembled ehrlichia risticii, the causative agent of phf. the minimum percentage of juga spp. harboring the organism in the population ...19989687446
survey of tick-borne diseases in dogs infested with rhipicephalus sanguineus at a kennel in okayama prefecture, japan.serological tests were performed to investigate extent of tick-borne diseases in dogs infested with rhipicephalus sanguineus at a kennel in okayama prefecture. three of 22 dogs (13.6%) were positive for ehrlichia canis. two of 19 dogs (10.5%) were positive for rickettsia japonica. three of 22 dogs (13.6%) were positive for babesia gibsoni. none of these animals were positive for coxiella burnetii or hepatozoon canis. a microfilaria was detected in a drop smear of hemolymph from an engorged femal ...19989673953
entomopathogenic nematodes as a potential biological control method for ticks.entomopathogenic nematodes have been used for biological control of certain insect pests. in these studies the nematodes were tested as a possible biological control agent for engorged female ticks. five species of infective juveniles (ijs) were tested initially for their ability to penetrate and kill ticks, including steinernema glaseri (sg), s. riobravus (sr), s. carpocapsae (dt), s. feltiae (sf) and heterorhabiditis bacteriophora (hp88). infective juveniles (ijs) of srs and sfs appeared to be ...19989668486
in vitro susceptibilities of 27 rickettsiae to 13 antimicrobials.the mics of 13 antibiotics (doxycycline, thiamphenicol, rifampin, amoxicillin, gentamicin, co-trimoxazole, ciprofloxacin, pefloxacin, ofloxacin, erythromycin, josamycin, clarithromycin, and pristinamycin) were determined for 27 available rickettsial species or strains. we used two in vitro cell culture methods described previously: the plaque assay and the microplaque colorimetric assay. our results confirm the susceptibilities of rickettsiae to doxycycline, thiamphenicol, and fluoroquinolones. ...19989660979
production and characterization of ehrlichia risticii, the agent of potomac horse fever, from snails (pleuroceridae: juga spp.) in aquarium culture and genetic comparison to equine strains.we report on the production and characterization of ehrlichia risticii, the agent of potomac horse fever (phf), from snails (pleuroceridae: juga spp.) maintained in aquarium culture and compare it genetically to equine strains. snails were collected from stream waters on a pasture in siskiyou county, calif., where phf is enzootic and were maintained for several weeks in freshwater aquaria in the laboratory. upon exposure to temperatures above 22 degrees c the snails released trematode cercariae ...19989620368
transmission of tick-borne bunyaviruses by cofeeding ixodid ticks.palma and bhanja bunyaviruses replicated in dermacentor marginatus, d. reticulatus, rhipicephalus sanguineus, r. appendiculatus and ixodes ricinus ticks after parenteral inoculation and appropriate incubation and feeding. palma virus was transmitted to d. marginatus and d. reticulatus males, d. reticulatus and r. sanguineus females, and r. appendiculatus nymphs while cofeeding with infected ticks on laboratory mice. bhanja virus was transmitted to d. marginatus males and r. appendiculatus nymphs ...19979607090
phylogenetic placement of rickettsiae from the ticks amblyomma americanum and ixodes scapularis.a rickettsial isolate (isolate moaa) belonging to the spotted fever group (sfg) was obtained from the lone star tick amblyomma americanum. we used pcr to characterize the genes for the rickettsial outer membrane proteins rompa and rompb. we sequenced the pcr products (domains i of both the rompa gene and the rompb gene) of moaa and wb-8-2, another rickettsial isolate from a. americanum. to place moaa and wb-8-2 and two other nonpathogenic isolates (rickettsia rickettsii hip2 and rickettsia monta ...19989574696
antibody response to hepatozoon canis in experimentally infected dogs.canine hepatozoonosis is a disease caused by the tick-borne protozoan hepatozoon canis. five puppies were inoculated by ingestion of rhipicephalus sanguineus ticks experimentally infected with h. canis, and all became infected with h. canis: gametocytes were detected in blood smears from four dogs and schizonts were observed in the spleen and bone marrow of the fifth. antibodies reactive with h. canis gametocytes were detected by the indirect fluorescent antibody test (ifa), with igm detected in ...19989561714
experimental transmission of ehrlichia canis (rickettsiales: ehrlichieae) by dermacentor variabilis (acari: ixodidae).four trials were conducted in which laboratory-reared dermacentor variabilis nymphs were exposed to ehrlichia canis by feeding on experimentally infected dogs as soon as classical morulae were detected in peripheral blood monocytes. after molting 25, 50 or 90 adult tick pairs were permitted to feed on 7 ehrlichia-naive dogs. transmission occurred in trials 1 (1/1 dog), 3 (1/1 dog) and 4 (2/2 dogs) but not in trial 2 (0/3 dogs), with 4 of 7 dogs becoming infected. successful transstadial transmis ...19989561712
taxonomic relationships among spotted fever group rickettsiae as revealed by antigenic analysis with monoclonal antibodies.the spotted fever group (sfg) is made up of more than 20 different rickettsial species and strains. study of the taxonomic relationships among the group has been attempted by phenotypic, genotypic, and phylogenetic analyses. in this study, we determined taxonomic relationships among the sfg rickettsiae by comparative analysis of immunogenic epitopes reactive against a panel of monoclonal antibodies. a total of 98 monoclonal antibodies, which were directed against epitopes on the major immunodomi ...19989542904
[imported arthropod-borne parasites and parasitic arthropods in dogs. species spectrum and epidemiologic analysis of the cases diagnosed in 1995/96].between january 1995 and december 1996 nonendemic or only regionally occurring arthropodborne parasites including ehrlichiae and parasitic arthropods in germany were detected in 484 dogs, whereby at least 15 species were involved. listed in decreasing order, leishmania infections occurred most frequently, followed by infections/infestations with babesia canis, ehrlichia canis, rhipicephalus sanguineus, dirofilaria immitis and dermacentor reticulatus. the other species, namely babesia gibsoni, tr ...19989531673
modifications of general parameters of immune activation in the sera of sicilian patients with boutonneuse fever.the serum levels of beta2-microglobulin (beta2-m), soluble hla class i antigen (shla-i), soluble cd4 (scd4) and cd8 (scd8) were studied in 98 sicilian patients with boutonneuse fever (bf). in different stages of infection all markers were significantly increased in sera from sicilian patients with acute bf compared with healthy controls. scd8 and shla-i reached the peak in the second week after the onset of symptoms, whereas scd4 and beta2-m reached the peak in the first week. afterwards scd8 de ...19989528898
doxycycline hyclate treatment of experimental canine ehrlichiosis followed by challenge inoculation with two ehrlichia canis strains.dogs were experimentally inoculated with ehrlichia canis florida to assess the efficacy of doxycycline hyclate for the treatment of acute ehrlichiosis. treatment with doxycycline eliminated infection in eight of eight dogs. untreated infected control dogs appeared to eliminate the infection or, alternatively, suppress the degree of ehrlichiemia to a level not detectable by tissue culture isolation or pcr or by transfusion of blood into recipient dogs. prior infection did not infer protection aga ...19989527787
distribution of borrelia burgdorferi s.l. spirochaete dna in british ticks (argasidae and ixodidae) since the 19th century, assessed by pcr.the distribution of borrelia burgdorferi sensu lato, the lyme borreliosis agent, was surveyed in british ticks in the collection of the natural history museum, london. alcohol-preserved specimens of eight species of ticks known to attack humans were studied: ixodes ricinus, i. hexagonus, i. uriae, i. trianguliceps, dermacentor reticulatus, haemaphysalis punctata, rhipicephalus sanguineus and argas vespertilionis. the sample comprised all life stages and originated from a wide range of host speci ...19989513944
amplification of ehrlichial dna from dogs 34 months after infection with ehrlichia canis.in order to determine whether dogs in the subclinical phase of canine monocytic ehrlichiosis (cme) are carriers of ehrlichia canis and to determine the significance of persistent indirect immunofluorescent anti-e. canis antibody titers during this phase, pcr was performed with blood, bone marrow, and splenic aspirates collected 34 months postinoculation from six clinically healthy beagle dogs experimentally infected with e. canis. at least one of the three samples (spleen, bone marrow, and blood ...19989431923
effect of infestation with rhipicephalus sanguineus on neutrophil function in dogs. 19979430122
a new hepatozoon species from dogs: description of the causative agent of canine hepatozoonosis in north america.a new species of adeleina, hepatozoon americanum, is described from the skeletal muscle, cardiac muscle, visceral organs, and blood of dogs (canis familiaris) in the southern united states. the organism was previously identified as hepatozoon canis (james, 1905) wenyon, 1926; however, differences in clinical signs, histopathological and serological findings, gamont size, and ultrastructure define the new species of hepatozoon. attempts to transmit the protozoan from infected dogs to nymphal rhip ...19979406796
rickettsiae-infected ticks in an endemic area of spotted fever in the state of minas gerais, brazil.a study on tick-borne rickettsiosis was developed in the county of santa cruz do escalvado, state of minas gerais, brazil, where a clinical case of the disease, confirmed by necropsy, had been reported. of the 1,254 ticks collected, 1,061 belonged to the amblyomma genus, 57 to the rhipicephalus sanguineus species, 81 to boophilus microplus, and 46 to anocentor nitens. the hemolymph test associated with giménez staining showed that 18 of the 221 a. cajennense specimens, 1 of the 16 r. sanguineus, ...19979361740
endosymbionts of ticks and their relationship to wolbachia spp. and tick-borne pathogens of humans and animals.the presence, internal distribution, and phylogenetic position of endosymbiotic bacteria from four species of specific-pathogen-free ticks were studied. these included the hard ticks ixodes scapularis (the black-legged tick), rhipicephalus sanguineus (the brown dog tick), and haemaphysalis longicornis and the african soft tick ornithodoros moubata. pcr assays for bacteria, using two sets of general primers for eubacterial 16s and 23s rrna genes (rdnas) and seven sets of specific primers for wolb ...19979327557
contribution to the knowledge of ixodidae ticks of wild mammals of somalia.this study was based on material collected in 1983-1984 from wild mammals of the middle scebeli. low scebeli and bay regions of somalia. a total of 292 specimens (156 males, 65 females, 70 nymphase, 1 larva) from 13 host species were examined. the following species of ixodidae were identified. amblyomma variegatum (fabricius, 1794); haemaphysalis calcarata neumann, 1902; haemaphysalis spinulosa neumann, 1906; rhipicephalus armatus pocock, 1900; rhipicephalus pravus donitz, 1910; rhipicephalus pu ...19969257347
effect of infestation with rhipicephalus sanguineus on the antibody productivity in dogs. 19979226654
ticks (acari: ixodida) uncommonly found biting humans in north carolina.collection records are presented that document human-biting by otobius megnini, amblyomma maculatum, haemaphysalis leporispalustris, ixodes cookei, ixodes dentatus, and rhipicephalus sanguineus in north carolina. these species are either extremely rare in north carolina or they are normally considered non-human feeders. the record of otobius megnini represents the first collection of this species in north carolina in over 50 years. it is proposed that immature rhipicephalus sanguineus feed on hu ...19979221733
epidemiological aspects of the brazilian spotted fever: seasonal activity of ticks collected in an endemic area in são paulo, brazil.ticks were collected from vegetation and animals at monthly intervals during one year (1993-1994) in an endemic area of brazilian spotted fever in the country of pedreira, state of são paulo. six species of ticks were identified amblyomma cajennense, amblyomma cooperi, amblyomma triste, anocentor nitens, rhipicephalus sanguineus and boophilus microplus. only the first species was sufficiently numerous to permit a quantitative study with seasonal activity, although the distribution and source of ...19979197151
epidemiologic evaluation of the risk factors associated with exposure and seroreactivity to bartonella vinsonii in dogs.to determine seroprevalence to bartonella vinsonii subsp berkhoffii in a population of sick dogs from north carolina and virginia and to evaluate potential risk factors associated with increased likelihood of exposure to the organism.19979140552
relationships between species of the rhipicephalus sanguineus group: a molecular approach.the biosystematic status of species belonging to the rhipicephalus sanguineus group is difficult to determine by phenotypic methods and has been subject to frequent revisions and ongoing debate. yet, the differentiation of species within this complex is of clinical importance especially in veterinary medicine due to different host specificities of the transmitted pathogens. in order to generate quantifiable and comparable data independent of environmental influences, a section of the second inte ...19979105315
[distribution of dog ticks (rhipicephalus sanguineus latreille, 1806) in italy: a public health problem].the dog tick, rhipicephalus sanguineus latreille, 1806 (acari: ixodidae), is a public health problem since it is widely distributed in italy and because of its role in the transmission of many pathogens to man and dog which is its preferred host. this review deals with the main aspects of the biology and ecology of rh. sanguineus habitat, developmental time, distribution and seasonality, behaviour and vector competence. moreover, the preminent role of rh, sanguineus in the transmission of bouton ...19969103161
rhipicephalus sanguineus and r. turanicus (acari:ixodidae): closely related species with different biological characteristics.life cycle parameters of 2 closely related tick species, rhipicephalus sanguineus latreille and r. turanicus pomerantsev, were studied under laboratory conditions. both rhipicephalus, which have small adults, demonstrated the same adaptations as large tick species inhabiting deserts and semideserts: high reproductive rate, decrease in egg size, and an increase in interstage growth to compensate for the smaller size at birth. pronounced quantitative differences between both species were discerned ...19979086715
tick zoonoses in the southern part of switzerland (canton ticino): occurrence of borrelia burgdorferi sensu lato and rickettsia sp.the diversity and the distribution of tick species and their infection rates by the pathogenic micro-organism borrelia burgdorferi sensu lato, the etiologic agent of lyme borreliosis, and rickettsia sp., were studied in canton ticino (the southern part of switzerland). ticks specimens collected from animals and humans were classified and analysed for the presence of both pathogens. in particular, pcr analysis was performed for the detection of borrelia spirochetes in ixodes ricinus and ixodes he ...19979085007
dogs develop resistance to rhipicephalus sanguineus.the capacity of beagle dogs to develop resistance against infestation by adult females of rhipicephalus sanguineus was investigated. the number of successive engorged females recovered from dogs at the second infestation of the tick was significantly less than at the first infestation. however, there were no significant differences in body weight, body length, body width of engorged females, feeding behavior, preoviposition periods or egg weight.19979066074
immunisation of dogs and guinea pigs against rhipicephalus sanguineus ticks using gut extract.tick-bite naive guinea pigs were inoculated three times with rhipicephalus sanguineus gut or salivary gland extracts and saponin as adjuvant. dogs were inoculated three times with gut extract only as this fraction induced a more efficient resistance in guinea pigs (lower tick recovery and lower engorged female weights). freund's adjuvant and saponin were used as adjuvants for the immunisation of dogs. freund's adjuvant was used to enhance cellular immunity. the highest level of resistance in dog ...19979066073
perceptions of veterinary clinics and pest control companies regarding tick-related problems in dogs residing in texas cities.to determine the extent and source of tick-related problems encountered by veterinary clinics and pest control company (pcc) clientele experiencing residential tick infestations in urban/suburban environments and to determine which tick-related diseases in dogs were diagnosed and treated at veterinary clinics.19979057918
prevalence of spotted fever group rickettsiae in ticks from southern israel.the prevalence of spotted fever group rickettsiae was studied in questing ticks collected from southern israel. ticks were examined from an agricultural settlement (kibbutz ze'elim), an endemic site for mediterranean spotted fever, and from another kibbutz (re'im) in an adjacent area where the disease has not been reported. ticks were collected by flagging and co2 traps from vegetation inside and outside the settlements during 1989/1990 and 1994. in ze'elim, 98% of the ticks collected were brown ...19968961650
attempted transmission of ehrlichia canis by rhipicephalus sanguineus after passage in cell culture.to compare the transmissibility by the brown dog tick, rhipicephalus sanguineus, of a recent isolate of ehrlichia canis (ebony) with that of another isolate (oklahoma) that had been passaged in cell culture, and to assess the genetic similarity of the 2 isolates as reflected in the nucleotide (nt) sequence of 16s rdna.19968915436
mediterranean spotted fever: a preliminary tick field study.we studied the prevalence of rickettsialike organisms infection in different tick species (3154 adults) collected in several areas of the ebro valley (spain). the gimenez stain showed a prevalence of rickettsia-like organisms in 38.6% of the studied ticks. using the immunofluorescence assay, only two species, rhipicephalus sanguineus (16.4%) and r. pusillus (19.9%) have shown organisms compatible with spotted fever group rickettsiae.19968905308
phenotypic and genotypic characterization of spotted fever group rickettsiae isolated from catalan rhipicephalus sanguineus ticks.eighty-nine rhipicephalus sanguineus ticks and 21 rhipicephalus bursa ticks collected in catalonia were tested by the hemolymph test to establish their infection rate with spotted fever group rickettsiae. by giménez staining, 11.2% of the r. sanguineus isolates and 0% of the r. bursa isolates were found to contain rickettsia-like organisms. six spotted fever group rickettsial strains (bar29, bar31, gir4, tar1, tar2, and tar3) were isolated from these ticks and were characterized by phenotypic an ...19968897166
isolation of a south african vector-specific strain of babesia canis.a south african strain of babesia canis parasites was isolated and shown to be vector-specific to only one of the two vectors in the region, haemaphysalis leachi. this tick was found to transmit the parasite in its adult instar. when infected as larvae, the ticks would not transmit in the proceeding nymphal instar. the vector-specific strain was named the 'thomas strain' after one of the dogs involved in isolating it. a survey revealed a prevalence of > 50% of this strain in four widely separate ...19968792576
seasonal occurrence of rhipicephalus sanguineus in okayama prefecture, japan and effect of temperature on development of the tick.the seasonal occurrence of rhipicephalus sanguineus on dogs was examined at a kennel in okayama prefecture, japan. the number of ticks suddenly decreased after treatment with an acaricide in late august. small numbers of adults and nymphs were detected in september and october, then ticks were not seen on the dogs early in november, when the mean temperature was below 15 degrees c. then 3 dogs were found to be infested by some adult ticks toward the end of march, when the mean temperature was ab ...19968777229
[the brown dog tick, rhipicephalus sanguineus (ixodidae), in germany: an epidemiologic study and control measures].between january and december 1995 infestations with rhipicephalus sanguineus were established in 22 dogs in germany. out of these 22 animals 2 originated from the endemic area of this tick species, spain and the dominican republic and 11 dogs accompanied their owner to the mediterranean countries, 5 to italy, 3 to france, 2 to spain and 1 animal to greece. six dogs had never left germany and with 3 dogs the way of infestation could not be reconstructed. in 16 cases an abundant occurrence of r. s ...19968765542
[the subspecies specificity of babesia canis].the large babesia species of dogs, babesia canis, is transmitted by different ticks. dermacentor reticulatus, rhipicephalus sanguineus and haemaphysalis leachi are the known main vectors. four b. canis isolates of different geographic origin were investigated for their transmission specificity and pathogenicity in infection trials. r. sanguineus ticks exclusively transmitted the babesia isolate from egypt. d. reticulatus was the vector for isolates from hungary and france. transmission of an sou ...19968765536
morphological keys for the separation of the rhipicephalus sanguineus group of ticks (acarina:ixodidae) in egypt.rhipicephalus sanguineus sensu stricto is the taxonomic baseline for the r. sanguineus group of ticks which consists of four species in egypt. because of the potential confusion in the differentiation of species within the group, particularly in the middle east, there is an urgent need for the development of new diagnostic keys. keys, based on morphological characters, are provided herein for the various stages of r. sanguineus ticks in egypt. an additional plan provides a useful tool for distin ...19968754653
the seasonal occurrence of ticks (acari: ixodidae) on sheep and in the field in the judean area of israel.a 2 year survey of ixodid ticks in the judean area of israel between 1983 and 1985 showed that sheep were parasitized by the following species: rhipicephalus sanguineus group (30.6%), rhipicephalus bursa (25.3%), haemaphysalis cretica (20.5%), haemaphysalis otophila (20.1%) and hyalomma anatolicum excavatum (3.1%). three other species, hyalomma marginatum rufipes, boophilus annulatus and amblyomma lepidum were also present but in very low numbers. a total of 50,816 specimens (78.1% adult ticks) ...19968746133
western blot analysis of tick antigens from a rhipicephalus sanguineus unfed larval extract and identification of antigenic sites in tick sections using immunohistochemistry. a comparative study between resistant and susceptible host species.most parasite-host relationships are characterized by the development of resistance by the host, thus limiting the number of parasites. however, some cases are very unusual. in the relationship of the domestic dog with the brown dog-tick rhipicephalus sanguineus this does not occur, whereas guinea pigs develop efficient resistance. sera from domestic dogs, crab-eating foxes and guinea pigs collected before and after infestation with r. sanguineus ticks, and after immunization with a whole tick a ...19968638389
ticks parasitizing humans in georgia and south carolina.from 1990 through 1995, 913 ticks removed from 460 human patients in georgia or south carolina were identified and recorded. the majority of these specimens (758, 83.0%) were lone star ticks, amblyomma americanum. one hundred and four (11.4%) american dog ticks dermacentor variabilis, 36 (3.9%) blacklegged ticks ixodes scapularis, 9 (1.0%) gulf coast ticks amblyomma maculatum, and 6 (0.7%) brown dog ticks rhipicephalus sanguineus were also recovered. all active stages (larvae, nymphs, and adults ...19968636862
ixodid ticks collected at the faculty of veterinary science, onderstepoort, from dogs diagnosed with babesia canis infection.in an attempt to identify the vectors of babesia canis, ticks were collected over a period of 3 years from a total of 395 dogs diagnosed as infected with this protozoan parasite at the veterinary faculty, onderstepoort. haemaphysalis leachi was the only tick species recovered from 164 of these dogs, and it occurred in mixed infestation on a further 140 of the dogs. rhipicephalus sanguineus was collected in pure infestation from 59 dogs with a further 87 harbouring mixed infestations. sixteen dog ...19958596189
genomic and proteinic characterization of strain s, a rickettsia isolated from rhipicephalus sanguineus ticks in armenia.strain s, a spotted fever group (sfg) rickettsia isolated from rhipicephalus sanguineus ticks collected in armenia, was identified. microimmunofluorescence, sodium dodecyl sulfate-polyacrylamide gel protein electrophoresis and western immunoblotting, pcr and then restriction fragment length polymorphism analysis, pulsed-field gel electrophoresis, and 16s rrna gene sequencing were used to compare strain s with reference isolates. strain s was found to possess proteinic, antigenic, and genomic pat ...19958567916
cutaneous hypersensitivity induced in dogs and guinea-pigs by extracts of the tick rhipicephalus sanguineus (acari: ixodidae).the cutaneous hypersensitivity induced by rhipicephalus sanguineus tick extract in dogs (natural host) and guinea-pigs (laboratory host) was evaluated. the left ear of infested and control (tick-bite naive) dogs and guinea-pigs was injected intradermally with an extract from unfed adult ticks and the right ear with phosphate buffered saline (pbs). ear thickness variations were then measured after 10 min and 1, 2, 6, 18, 24, 48, 72 and 96 h post-injection. results were expressed as percentual cha ...19958556961
prevalence of rickettsia-like organisms and spotted fever group rickettsiae in ticks (acari: ixodidae) from zimbabwe.the prevalence of rickettsia-like organisms in ticks from zimbabwe was determined using the hemolymph test. amblyomma hebraeum had the highest prevalence of rickettsia-like organisms. other species with rickettsia-like organisms included amblyomma sparsum, amblyomma variegatum, hyalomma marginatum rufipes, ripicephalus simus, haemaphysalis leachi, amblyomma rhinocerotis, and hyalomma truncatum. ticks with no demonstrable rickettsia-like organisms infection were boophilus decoloratus, haemaphysal ...19958551500
analysis of stage-specific and shared antigens derived from rhipicephalus sanguineus by electrophoresis and western blotting.we carried out an sds-page analysis of antigens of rhipicephalus sanguineus using extracts of eggs (ee), larvae (le), nymphs (ne), male salivary glands (msge), male midguts (mme), female salivary glands (fsge) and female midguts (fme). under non-reducing conditions a common band of about 205 kda was observed. ee, le and ne extracts showed groups of bands between 150 and 75 kda. a protein pattern was observed in fsge extract with a group of bands between 75 and 50 kda and four bands between 15 an ...19958541584
canine ehrlichiosis in egypt: sero-epidemiological survey.a total of 374 dogs, 252 from five military kennels and 122 privately owned, were tested for ehrlichia canis antibody. sera were tested at a 1:20 dilution by indirect fluorescent antibody with the use of e. canis cell-culture antigen slides. the overall prevalence of e. canis antibody was 33%. antibody prevalence among military dogs (29%) was significantly lower than among privately owned dogs (41%; p < 0.05). the e. canis seroprevalence among dogs infested with ticks (rhipicephalus sanguineus) ...19958539033
ecological studies on the brown dog tick rhipicephalus sanguineus (acari: ixodidae) in southern israel and its relationship to spotted fever group rickettsiae.an outbreak of spotted fever group rickettsiae (sfgr) was investigated by studying free-living and parasitic stages of ticks in two settlements of equal size and population located 20 km apart in the negev desert. although high morbidity from sfgr was found in one of the settlements (kibbutz ze'elim), no clinical cases were observed in the second (kibbutz re'im). using flagging and co2-trapping, approximately 9 times more ticks were collected in ze'elim than in re'im. rhipicephalus sanguineus (l ...19938433318
climate and cuticular hydrocarbon variation in rhipicephalus sanguineus ticks (acari: ixodidae).an association between the climate and variation of the cuticular hydrocarbon pattern was found for several populations of rhipicephalus sanguineus ticks. extreme parameters of climate (absolute minimal and maximal temperatures) correlated positively with six compounds (mainly methylalkanes) detected in cuticular hydrocarbon mixtures. in the light of work conducted on cuticular transpiration in arthropods and biochemical phase changes in cuticle lipids, it is suggested that the adaptation of tic ...19938415569
distribution and host-relationship of ticks (ixodoidea) infesting domestic animals and rodents in sinai peninsula.geographical distribution of ticks infesting farm animals in sinai peninsula revealed the presence of 12 tick species namely hyalomma dromedarii, h. impeltatum, h. an anatolicum, h. an. excavatum, h. marginatum rufipes, h. m. turanicum, h. schulzei, rhipicephalus sanguineus, r. turanicus, boophilus annulatus, ornithodors erraticus and argas persicus. the distribution map of those species is given. the areas of sinai could be arranged as regards the number of tick species in the following descend ...19938376863
experimental transmission of dipetalonema dracunculoides (cobbold 1870) by rhipicephalus sanguineus (latreille 1806).a dog naturally infected with dipetalonema dracunculoides and having a microfilaremia of 6050 microfilariae per mm3 of blood was used as source of infection. experimentally cultivated nymphs of rhipicephalus sanguineus were fed on the donor dog. once engorged, ninety-three nymphs were removed and kept at 30 degrees c and rh 90% until they moulted to the adult stage. to study the development of microfilariae in the vector, ten ticks were dissected at day 37 post-infection. adult infected ticks we ...19938333138
[ticks in the region of belgrade].the paper gives a brief introduction concerning the role of ticks in transmission of numerous diseases to both animals and humans. methods of work, research goals and finally, results of tick findings on animals and people in belgrade area are presented. occasional findings of those arthropodes in various urban areas have also been described. the collected ticks belong to the species ixodes ricinus and rhipicephalus sanguineus. the authors conclude that ecologic research of ticks should be conti ...19938262431
ticks (acari: ixodidae) infesting medium-sized wild mammals in southwestern tennessee.seven species of ixodid ticks (n = 2,661) were found on medium-sized wild mammals (n = 295) during a 13-mo study in shelby county, tennessee. the seven tick species collected were dermacentor variabilis (say), amblyomma americanum (l.), rhipicephalus sanguineus (latreille), ixodes texanus (banks), i. cookei (packard), i. scapularis (say), and haemaphysalis leporispalustris (packard). the raccoon had the greatest tick species diversity in all of the aforementioned ticks except h. leporispalustris ...19938254637
geographical distribution, host associations, and vector roles of ticks (acari: ixodidae, argasidae) in sweden.this review covers the geographic distribution and host relationships of the tick species in sweden. ixodes uriae white, i. caledonicus nuttall, i. unicavatus neumann, i. arboricola schulze & schlottke, and i. lividus koch are ornithophagous species. i. trianguliceps birula, i. canisuga johnston, i. hexagonus leach, and argas vespertilionis (latreille) are mammalophagous. i. ricinus (l.) and haemaphysalis punctata canestrini & fanzago feed on both birds and mammals. all these tick species may be ...19948189415
immunisation of dogs, hamsters and guinea pigs against rhipicephalus sanguineus using crude unfed adult tick extracts.naive experimental groups of dogs, hamsters and guinea pigs were inoculated three times subcutaneously with unfed adult extract of the tick rhipicephalus sanguineus and challenged with adult r. sanguineus to evaluate resistance. the acquisition of resistance was based on alterations of some reproductive and feeding performance parameters of female ticks such as female and egg mass weights, engorgement, pre-oviposition and incubation periods, larval hatchability rate and efficiency rates of femal ...19948030191
immunological response in rabbits infested with rhipicephalus sanguineus.in order to clarify the importance of humoral antibody in host resistance to ticks, in the present work we studied the immunological response of rabbits infested with larvae, nymphs or adults of rhipicephalus sanguineus, using extracts of eggs (ee), larvae (le), nymphs (ne), male salivary glands (msge), male midguts (mme), female salivary glands (fsge) and female midguts (fme). when serum from rabbits infested with larvae or nymphs was tested using enzyme-linked immunosorbent assay, no reactions ...19947949315
isolation and identification of a rickettsial strain related to rickettsia massiliae in greek ticks.adult ticks were collected in a rural area of central greece in order to isolate and identify rickettsiae. a hemolymph test using gimenez staining was used for detection, while simultaneous isolation was performed using the shell-vial technique. serologic, antigenic, and genomic characterization of the isolates was achieved by microimmunofluorescence, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) and western blotting, the polymerase chain reaction and restriction fragment ...19947908503
rickettsiae and their ecology in the alpine region.two rickettsioses are known to be distributed in the alpine region, the ubiquitous q fever and the so called tick-bite fever (fever boutonneuse) which is due to rickettsia conorii. the latter is only temporarily seen and brought in via dogs by the dog tick rhipicephalus sanguineus from italy and southern france. further, the presence of two apathogenic rickettsiae, r. slovaca (in austria, switzerland, germany) and r. helvetica (switzerland) has been determined. the present paper will discuss eco ...19937905244
genotypic evaluation of rickettsial isolates recovered from various species of ticks in portugal.twelve rickettsial isolates, from rhipicephalus sanguineus, r. turanicus, dermacentor marginatus and hyalomma marginatus, were subjected to genotypic analysis. amplification of specific dna sequences, restriction endonuclease digestion of amplified dna products, and gel electrophoresis were used to identify specific dna fragment-banding patterns. five patterns were resolved. four were homologous with those of previously described rickettsial genotypes, r. conorii, r. slovaca, r. rhipicephali and ...19957867736
stage-specific development of a filarial nematode (dipetalonema dracunculoides) in vector ticks.this paper reports the development of the canid filarial worm, dipetalonema dracunculoides, in the brown dog tick, rhipicephalus sanguineus by determining whether development is similar within larval, nymphal and adult stages of infected ticks. this study demonstrates that only infected nymphal ticks can support the complete development of the filarial worm. infected larval ticks are not suitable intermediate hosts, nor are infected adults. development depends on some stage-specific property of ...19947829843
development of babesia gibsoni in the salivary glands of the larval tick, rhipicephalus sanguineus.the development of babesia gibsoni in the salivary glands of larval rhipicephalus sanguineus ticks was morphologically studied for 4 days of feeding of tick on rabbits. babesia gibsoni showed two forms (sporont and sporozoite) in the budding process. sporozoites were formed in the acinar cells of salivary glands and released from the hollow cytoplasmic area of these cells by day 4 of feeding. the morphology of b. gibsoni in the salivary glands of r. sanguineus shows a close similarity to those o ...19957756402
elisa screening for lyme disease in children with chronic arthritis.one hundred patients, aged 6-15 years and presented to el-shatby university children's hospital with chronic/recurrent arthritis and skin lesions suggestive of erythema chronicum migrans (ecm), were investigated for presence of igg antibodies against borrelia burgdorferi flagellum antigen elisa test. four cases yielded positive serum samples which were true positive cases as they showed negative venereal disease research laboratory (vdrl) test. ticks collected from domestic animals from the hous ...19957665949
[parasitic horse ticks in italy. observations on their distribution and pathogenic role].the following 13 species of ticks, belonging to ixodidae family, were recorded in italy on horse (equus caballus) since 1931: ixodes ricinus, i. gibbosus, haemaphysalis inermis, h. parva, h. punctata, h. sulcata, dermacentor marginatus, rhipicephalus sanguineus, rh. bursa, rh. turanicus, hyalomma marginatum, hy. detritum, boophilus annulatus. the regional distribution and the role of the species in the transmission of pathogens are reported.19947637997
cholesteryl esters on the body surfaces of the camel tick, hyalomma dromedarii (koch, 1844) and the brown dog tick, rhipicephalus sanguineus (latreille, 1806).cholesteryl esters were found to constitute a major component of the lipids coating the body cuticle of females of the camel tick, hyalomma dromedarii and the brown dog tick, rhipicephalus sanguineus. one or more cholesteryl esters, alone or in combination, have been shown to serve as the mounting sex pheromone of several species of ixodid ticks. consequently, knowledge of these compounds is important for an understanding of the mating behavior of these ticks. based on thin layer chromatography, ...19947628247
rhipicephalus sanguineus: observations on the parasitic stage on dogs in the negev desert of israel.sixteen dogs were studied for infestation with r. sanguineus in kibbutz ze'elim in the northwestern part of the negev desert over a period of one year. the mean number of ticks per dog per month was 16.4. the majority of the ticks were adults: males (48.6%) and females (34.4%). the ears and abdomen of the dog were the predilection sites for the ticks. male ticks were more abundant on the ears, whereas female ticks were more abundant on the ears and the abdomen. a strong correlation between tick ...19937628225
incidence of brown dog ticks, rhipicephalus sanguineus, at a kennel in okayama prefecture.twenty two adult dogs suffered from tick infestation at a kennel in okayama prefecture in the summer of 1994. four of them had been introduced from u.s.a. some dogs showed pyoderma, anemia, neutrophilia or eosinophilia. neither babesia gibsoni nor hepatozoon canis was detected on the smear samples of peripheral blood. the ticks detected were morphologically identified as rhipicephalus sanguineus. this case was a rare incidence of the tick in the other areas of japan than okinawa.19957548423
rhipicephalus sanguineus latreille, the causative agent of foreign body in the ear: distribution on the body of dog. 19807420007
[the brown dog tick rhipicephalus sanguineus latreille 1806 in the netherlands, an analysis of imported cases, including their veterinary and medical significance (author's transl)].eighteen cases of infestation with rhipicephalus sanguineus were reported during the past five years. of the cases, six were observed during the first seven months of 1979. of all infestations, four originated from sources within the territory of the netherlands. several cases of infestation with canine babesiosis were reported. there could have been a relationship between some of these cases and infestation with r. sanguineus. populations of this tick can survive and develop in dutch homes. for ...19807368198
a note on attachment sites of rhipicephalus sanguineus (lat.) (acarina) on indian hedgehog hemiechinus auritus collaris (gray) (insectivora : erinacidae). 19817343595
trials on cross-mating between three species of rhipicephalus sanguineus group (ixodoidea : ixodidae). 19817299168
water vapour absorption and transpiration in the brown dog tick rhipicephalus sanguineus latr. (ixodidae, acarina). 19817299145
cutaneous basophil responses and immune resistance of guinea pigs to ticks: passive transfer with peritoneal exudate cells or serum.resistance to infestation by larval amblyomma americanum or rhipicephalus sanguineus ticks was transferred to naive guinea pigs with peritoneal exudate cells (pec) or serum from donors immunized by prior infestation with homologous tick larvae. in the a. americanum system, pec transfer induced 87% tick rejection, which was similar to the level of resistance in actively sensitized hosts. in the r. sanguineus system, pec conferred resistance (39% rejection) that was weaker than in actively sensiti ...19817299125
[characteristics of the "tache noire" of boutonneuse fever].humans show little sensitivity to the bites of healthy rhipicephalus sanguineus and the skin lesion is extremely slight. the "tache noire" - innoculation eschar - corresponding to the infecting bite of the tick with r. conori is discussed and histopathological findings reported. the patient is frequently unaware of the eschar on his body and elements relating to the duration of the infecting bite are deduced. apart from its typical features, the tache noire may be very small, with surrounding hy ...19817254648
observation on the saliva and salivary gland extract of haemaphysalis spinigera and rhipicephalus sanguineus sanguineus.intracutaneous injection of histamine acid phosphate (hap) and salivary gland extract (sge) of haemaphysalis spinigera and rhipicephalus sanguineus sanguineus into sensitized and nonsensitized rabbits previously injected intravenously with evans blue indicated that the ticks' saliva contained a pharmacodynamic substance in addition to having antigenic properties. a primary skin reaction in nonsensitized rabbits produced by this pharmacodynamic substance within 30 min was amplified by a more exte ...19817229815
the temperature and humidity preferences of haemaphysalis longicornis, ixodes holocyclus and rhipicephalus sanguineus (ixodidae): studies on engorged larvae. 19817228486
natural occurrence of coxiella burnetii in the brown dog tick rhipicephalus sanguineus. 19807191407
observations on the epidemiology of house infesting rhipicephalus sanguineus in a household in lagos, nigeria. 19827186809
scavenging dogs and the spread of tick infestation in nigeria.a dog, on whose body ticks were found early in january, 1977, was kept in the household during the night but allowed to scavenge during the day without the ticks being removed throughout the year. weekly counts of the number of different stages of ticks found on the body were made and the behaviour of the engorged dropped ones was studied. the preoviposition, oviposition and preeclosion periods of replete ticks were also studied. rhipicephalus sanguineus and haemaphysalis leachi leachi were the ...19827169311
immune serum transfer of cutaneous basophil-associated resistance to ticks: mediation by 7sigg1 antibodies.guinea pigs acquired resistance to amblyomma americanum larval ticks after one infestation, resulting in 46% tick rejection when challenged. intravenous transfer of immune serum from twice-infested hosts to naive animals conferred a significant level of immunity resulting in 18 to 30% tick rejection. the minimum effective dose of serum was 3 ml per recipient, and heating the serum at 56 degrees c for 4 hr had no effect on serum activity. fractionation of whole immune serum by gel filtration chro ...19827142697
effect of medium supplements on tick cells in culture.the growth of tick cells in leibovitz's l--15 medium supplemented with various concentrations of fetal bovine serum (fbs), tryptose phosphate broth (tpb), and tick egg extract (tee) was evaluated using a protein assay. a continuous cell line from rhipicephalus appendiculatus (ra 243) was compared with young lines of cells isolated from embryos of r. appendiculatus (rae 25) and rhipicephalus sanguineus (rse 8). we found fetal bovine serum and tryptose phosphate broth both to be essential suppleme ...19827131199
prevalence of cattle ticks in morocco.during july 1980 the prevalence of cattle ticks was studied in 4 bioclimatic regions of morocco. all the 24 farms examined were infested. the mean number of ticks per animal varied from 6.5 to 36.3 in different regions. eight species of ticks were identified: hyalomma marginatum, h. detritum, h. lusitanicum, h. anatolicum, boophilus annulatus, rhipicephalus sanguineus, r. turanicus, r. bursa. numerically h. detritum (30.8%) h. marginatum (25.5%) and b. annulatus (29.2%) were most important. the ...19827123663
parasites of domestic and wild animals in south africa. xiv. the seasonal prevalence of rhipicephalus sanguineus and ctenocephalides spp. on kennelled dogs in pretoria north.the seasonal prevalence of rhipicephalus sanguineus and ctenocephalides spp. on kennelled dogs in pretoria north was determined by the regular examination of 3, initially, and later 2 dogs from march 1975--january 1977. once the ticks had become established in the kennel peak burdens of immature ticks (larvae plus nymphae) were present on the dogs during early summer 1975 and from midsummer--late summer 1976 and early midsummer 1976/77. peak numbers of adult ticks were present in midsummer 1975/ ...19827122067
change in weight and mortality rate of adult rhipicephalus sanguineus latreille, 1806 (ixodoidea : ixodidae) conditioned at different relative humidities. 19827086232
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