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identity and transfer of male reproductive gland proteins of the dengue vector mosquito, aedes aegypti: potential tools for control of female feeding and reproduction.male reproductive gland proteins (mrgps) impact the physiology and/or behavior of mated females in a broad range of organisms. we sought to identify mrgps of the yellow fever mosquito, aedes aegypti, the primary vector of dengue and yellow fever viruses. earlier studies with ae. aegypti demonstrated that "matrone" (a partially purified male reproductive accessory gland substance) or male accessory gland fluid injected into virgin female ae. aegypti affect female sexual refractoriness, blood feed ...200818207079
isolation, cloning and structural characterisation of boophilin, a multifunctional kunitz-type proteinase inhibitor from the cattle tick.inhibitors of coagulation factors from blood-feeding animals display a wide variety of structural motifs and inhibition mechanisms. we have isolated a novel inhibitor from the cattle tick boophilus microplus, one of the most widespread parasites of farm animals. the inhibitor, which we have termed boophilin, has been cloned and overexpressed in escherichia coli. mature boophilin is composed of two canonical kunitz-type domains, and inhibits not only the major procoagulant enzyme, thrombin, but i ...200818286181
prevention of infectious tick-borne diseases in humans: comparative studies of the repellency of different dodecanoic acid-formulations against ixodes ricinus ticks (acari: ixodidae).abstract:200818397516
cellular and molecular characterization of an embryonic cell line (bme26) from the tick rhipicephalus (boophilus) microplus.the cellular and molecular characteristics of a cell line (bme26) derived from embryos of the cattle tick rhipicephalus (boophilus) microplus were studied. the cells contained glycogen inclusions, numerous mitochondria, and vesicles with heterogeneous electron densities dispersed throughout the cytoplasm. vesicles contained lipids and sequestered palladium meso-porphyrin (pd-mp) and rhodamine-hemoglobin, suggesting their involvement in the autophagic and endocytic pathways. the cells phagocytose ...200818405834
amblyomma variegatum in cattle in marie galante, french antilles: prevalence, control measures, and infection by ehrlichia ruminantium.we report marie galante as one of the caribbean islands most heavily infested by the tropical bont tick (tbt) amblyomma variegatum which is associated with two major diseases of ruminants: heartwater and dermatophilosis. in 2005, a survey was undertaken to assess the prevalence of tbt infestation in cattle, the prevalence of ehrlichia ruminantium infection in tbts, and the tick control measures implemented by livestock owners. a random sample of 195 cattle herds out of 1885 recorded on the islan ...200818406061
a quantitative real-time pcr assay for ehrlichia ruminantium using pcs20.heartwater is a tick borne disease that affects ruminants and wild animals in africa south of the sahara. it is caused by ehrlichia ruminantium and transmitted by the tick amblyomma hebraeum. the protocols currently used to detect heartwater take several days to complete. here, we describe the development of a pcs20 quantitative real-time pcr taqman probe assay to detect e. ruminantium in livestock blood and ticks from the field. the assay is based on the conserved pcs20 gene region of e. rumina ...200818511221
identification of two genes essential for sperm development in the male tick amblyomma hebraeum koch (acari: ixodidae).in most ticks of the family ixodidae, gonad maturation and spermatogenesis are stimulated by the taking of a blood meal. previous work from this laboratory identified 35 genes that are up-regulated by feeding [weiss, b.l., stepczynski, j.m., wong, p., kaufman, w.r., 2002. identification and characterization of genes differentially expressed in the testis/vas deferens of the fed male tick, amblyomma hebraeum. insect biochemistry and molecular biology 32, 785-793]. the functions of most of these g ...200818549958
climate extremes promote fatal co-infections during canine distemper epidemics in african lions.extreme climatic conditions may alter historic host-pathogen relationships and synchronize the temporal and spatial convergence of multiple infectious agents, triggering epidemics with far greater mortality than those due to single pathogens. here we present the first data to clearly illustrate how climate extremes can promote a complex interplay between epidemic and endemic pathogens that are normally tolerated in isolation, but with co-infection, result in catastrophic mortality. a 1994 canine ...200818575601
effect of 20-hydroxyecdysone and haemolymph on oogenesis in the ixodid tick amblyomma hebraeum.earlier work from our laboratory indicated that injection of 20-hydroxyecdysone (20e) into non-vitellogenic female amblyomma hebraeum ticks stimulates the synthesis of vitellogenin (vg), but not its uptake into oocytes [friesen, k., kaufman, w.r., 2004. effects of 20-hydroxyecdysone and other hormones on egg development, and identification of a vitellin-binding protein in the ovary of the tick, amblyomma hebraeum. journal of insect physiology 50, 519-529]. in contrast, thompson et al. [thompson, ...200818634796
an insight into the salivary transcriptome and proteome of the soft tick and vector of epizootic bovine abortion, ornithodoros coriaceus.the salivary glands of blood-sucking arthropods contain a redundant 'magic potion' that counteracts their vertebrate host's hemostasis, inflammation, and immunity. we here describe the salivary transcriptome and proteomics (sialome) of the soft tick ornithodoros coriaceus. the resulting analysis helps to consolidate the classification of common proteins found in both soft and hard ticks, such as the lipocalins, kunitz, cystatin, basic tail, hebraein, defensin, til domain, metalloprotease, 5'-nuc ...200818725333
science and popular participation in the investigation of heartwater in south africa, c. 1870-1950.during the late nineteenth century, settler farmers in southern africa identified heartwater as a damaging disease of small stock and cattle. they advanced various explanations of the disease, including the theory that it was caused by the bite of ticks. around 1900, the american entomologist c.p. lousbury demonstrated that heartwater was transmitted by the bont tick. he also worked out the life cycle and life habits of the tick. subsequently, farmers developed methods of controlling ticks by di ...200820055238
ixodid ticks infesting domestic goats in communal land areas of zimbabwe.the purpose of this study was to determine the species spectrum of ticks infesting goats owned by resource-limited farmers in the state-owned communal land areas of zimbabwe. ticks were collected from goats at a single locality within each of 5 communal land areas, and a total of 14 ixodid tick species was recovered. the most numerous tick was rhipicephalus evertsi evertsi, which was present in all areas at each sampling, and a rhipicephalus sp. (near r. punctatus), which was most abundant on go ...200819244819
diversity of ehrlichia ruminantium major antigenic protein 1-2 in field isolates and infected sheep.proteins expressed from the map1 multigene family of ehrlichia ruminantium are strongly recognized by immune t and b cells from infected animals or from animals that were infected and have recovered from heartwater disease (although still remaining infected carriers). analogous multigene clusters also encode the immunodominant outer membrane proteins (omps) in other ehrlichial species. recombinant protein analogs of the expressed genes and dna vaccines based on the multigene clusters have been s ...200919307215
analysis of the rickettsia africae genome reveals that virulence acquisition in rickettsia species may be explained by genome reduction.the rickettsia genus includes 25 validated species, 17 of which are proven human pathogens. among these, the pathogenicity varies greatly, from the highly virulent r. prowazekii, which causes epidemic typhus and kills its arthropod host, to the mild pathogen r. africae, the agent of african tick-bite fever, which does not affect the fitness of its tick vector.200919379498
immunisation with recombinant proteins subolesin and bm86 for the control of dermanyssus gallinae in poultry.dermanyssus gallinae has a worldwide distribution and is considered to be the most serious and economically significant ectoparasite affecting egg-laying poultry in europe. recombinant bm86 and subolesin proteins derived from boophilus microplus ticks and aedes albopictus mosquitoes were used to immunise poultry in an attempt to control d. gallinaein vitro. immunisation with subolesin and bm86 stimulated different profiles of igy response, whilst bm86 but not subolesin was recognized by igy on w ...200919501789
microarray analysis of gene expression changes in feeding female and male lone star ticks, amblyomma americanum (l).a collection of est clones from female tick amblyomma americanum salivary glands was hybridized to rna from different feeding stages of female tick salivary glands and from unfed or feeding adult male ticks. in the female ticks, the expression patterns changed dramatically upon starting feeding, then changed again towards the end of feeding. on beginning feeding, genes possibly involved in survival on the host increased in expression as did many housekeeping genes. as feeding progressed, some of ...200919514082
male engorgement factor: role in stimulating engorgement to repletion in the ixodid tick, dermacentor variabilis.mating in ticks results in profound physiological changes that eventually results in egg production. in the american dog tick, dermacentor variabilis, mating causes partially blood-fed female ticks to commence rapid engorgement to repletion and eventual detachment from the host and egg laying. the peptidic male pheromone (engorgement factor alpha/beta) transferred to the female during mating is known only from a single tick species, amblyomma hebraeum, and was shown to consist of two peptides pr ...200919538967
salivary gland degeneration and vitellogenesis in the ixodid tick amblyomma hebraeum: surpassing a critical weight is the prerequisite and detachment from the host is the trigger.the normal engorged body weight of female ixodid ticks (acari: ixodidae) is about 100x the unfed weight. virgin female amblyomma hebraeum normally do not feed beyond 10x the unfed weight. however, about 10-20% of a population of virgins will feed to perhaps 20x the unfed weight, but not much beyond that. in a. hebraeum, when females surpass about 10x the unfed weight, the following changes in physiology occur if they are removed from the host: (a) they will not reattach if given the opportunity, ...200919555693
cloning and characterization of rhipicephalus appendiculatus voraxinalpha and its effect as anti-tick vaccine.male tick-derived voraxinalpha and voraxinbeta, a pair of testicular proteins, are transferred to female via copulation to stimulate female blood feeding in the tick amblyomma hebraeum (a. hebraeum). immunized animals with recombinant (r-)voraxinalpha and voraxinbeta have been shown as highly resistant to the tick infestation. in this study, we describe the cloning and characterization of voraxinalpha homologue from the tick rhipicephalus appendiculatus (r. appendiculatus), the major vector for ...200919665610
structure and mode of action of microplusin, a copper ii-chelating antimicrobial peptide from the cattle tick rhipicephalus (boophilus) microplus.microplusin, a rhipicephalus (boophilus) microplus antimicrobial peptide (amp) is the first fully characterized member of a new family of cysteine-rich amps with histidine-rich regions at the n and c termini. in the tick, microplusin belongs to the arsenal of innate defense molecules active against bacteria and fungi. here we describe the nmr solution structure of microplusin and demonstrate that the protein binds copper ii and iron ii. structured as a single alpha-helical globular domain, micro ...200919828445
whartonacarus floridensis sp. nov. (acari: trombiculidae), with a taxonomic review and the first record of whartonacarus chiggers in the continental united states.among several unusual species collected during surveillance of ectoparasites on wildlife hosts in the southeastern united states and caribbean region, the larvae of a new species of whartonacarus were encountered in 2003 on a cattle egret, bubulcus ibis (l.), in the florida keys. this is the first record for a member of whartonacarus in the continental united states. the mite is described and named as whartonacarus floridensis mertins, and the possible significance of this discovery with respect ...200919960669
surveys for ectoparasites on wildlife associated with amblyomma variegatum (acari: ixodidae)-infested livestock in st. croix, u.s. virgin islands.surveys in 2001, 2005, and 2006 attempted to determine the role of wildlife in maintenance and dissemination of the tropical bont tick, amblyomma variegatum (f.) (acari: ixodidae), in st. croix, u.s. virgin islands. small mammals; birds; white-tailed deer, odocoileus virginianus (zimmermann); and feral cattle, bos taurus l., were examined at nine premises, in mountainous rain forest, and in surrounding areas in western st. croix, an area including and central to all known bont tick-infested prem ...200919960701
the impact of rna interference of the subolesin and voraxin genes in male amblyomma hebraeum (acari: ixodidae) on female engorgement and oviposition.reducing or replacing the use of chemical pesticides for tick control is a desirable goal. the most promising approach would be to develop vaccines that protect hosts against tick infestation. antigens suitable for the development of anti-tick vaccines will likely be those essential for vital physiological processes, and in particular those directly involved in feeding and reproduction. in this study genes from amblyomma hebraeum koch that encode for subolesin and voraxin were studied in male ti ...200918830675
identification of a complex peptidergic neuroendocrine network in the hard tick, rhipicephalus appendiculatus.neuropeptides are crucial regulators of development and various physiological functions but little is known about their identity, expression and function in vectors of pathogens causing serious diseases, such as ticks. therefore, we have used antibodies against multiple insect and crustacean neuropeptides to reveal the presence of these bioactive molecules in peptidergic neurons and cells of the ixodid tick rhipicephalus appendiculatus. these antibodies have detected 15 different immunoreactive ...200919082627
ticks collected from birds in the northern provinces of south africa, 2004-2006.approximately 3000 birds, mainly passerines, caught in mist nets in the northern provinces of south africa, were examined for ticks. a total of 178 ticks, belonging to 14 species, were recovered from 83 birds of 43 different species. hyalomma rufipes was the most numerous tick, with 26 larvae and 109 nymphs collected, followed by amblyomma marmoreum, with 13 larvae and two nymphs. despite the study being conducted within the distribution range of amblyomma hebraeum, it was not seen on any passer ...200920698437
the comparative prevalence of five ixodid tick species infesting cattle and goats in maputo province, mozambique.this study compares the prevalence of ixodid tick species on cattle and goats in maputo province. adult ticks as well as the nymphs of three species, and only the adults of two species were collected from sets of five cattle at 21 localities throughout the province and compared with those collected from similar sets of goats at the same places. amblyomma hebraeum adults and/or nymphs were present on cattle and on goats at all 21 localities, and 90 cattle and 22 goats were infested with adult tic ...200920698440
tick infestation, and udder and teat damage in selected cattle herds of matabeleland south, zimbabwe.a cross-sectional survey was conducted to determine tick infestation, and udder and teat damage in 286 lactating cows and heifers at six properties in the smallholder and commercial sectors in gwanda district of matabeleland south province, zimbabwe. eight tick species were identified: amblyomma hebraeum, hyalomma truncatum, hyalomma marginatum rufipes, rhipicephalus evertsi evertsi, rhipicephalus (boophilus) decoloratus, rhipicephalus appendiculatus, rhipicephalus zambeziensis and rhipicephalus ...200920698443
species composition and geographic distribution of ticks infesting cattle, goats and dogs in a temperate and in a subtropical region of south-east africa.the species and distribution of ticks infesting cattle, goats and dogs in the eastern region of the eastern cape province, south africa and maputo province, mozambique were determined from collections made from these animals at 72 localities in the former region and 30 in the latter. eleven ixodid and one argasid species were recovered in the eastern cape province and 15 ixodid species in maputo province. the most common ticks infesting cattle and goats in both provinces were amblyomma hebraeum, ...200921105593
a potential role for ixodid (hard) tick vectors in the transmission of lumpy skin disease virus in cattle.lumpy skin disease (lsd) is an economically important cattle disease. the disease is endemic in many african countries, but outbreaks have also been reported in madagascar and the middle east. the aim of this study was to investigate the potential role of ixodid (hard) ticks in the transmission of the disease. cattle were infected with a virulent, south african field isolate of lumpy skin disease virus (lsdv). three common african tick species (genera rhipicephalus, amblyomma and rhipicephalus ( ...201021114790
veterinary extension on sampling techniques related to heartwater research.heartwater, a tick-borne disease caused by ehrlichia ruminantium, is considered to be a significant cause of mortality amongst domestic and wild ruminants in south africa. the main vector is amblyomma hebraeum and although previous epidemiological studies have outlined endemic areas based on mortalities, these have been limited by diagnostic methods which relied mainly on positive brain smears. the indirect fluorescent antibody test (ifa) has a low specificity for heartwater organisms as it cros ...201021247042
progress and obstacles in vaccine development for the ehrlichioses.ehrlichia are tick-borne obligately intracellular bacteria that cause significant diseases in veterinary natural hosts, including livestock and companion animals, and are now considered important zoonotic pathogens in humans. vaccines are needed for these veterinary and zoonotic human pathogens, but many obstacles exist that have impeded their development. these obstacles include understanding genetic and antigenic variability, influence of the host on the pathogen phenotype and immunogenicity, ...201020822349
tick-borne rickettsioses, neglected emerging diseases in rural senegal.rickettsioses are one of the most important causes of systemic febrile illness among travelers from developed countries, but little is known about their incidence in indigenous populations, especially in west africa.201020856858
thrombin inhibitors from different animals.venous and arterial thromboembolic diseases are still the most frequent causes of death and disability in high-income countries. clinical anticoagulants are inhibitors of enzymes involved in the coagulation pathway, such as thrombin and factor x(a). thrombin is a key enzyme of blood coagulation system, activating the platelets, converting the fibrinogen to the fibrin net, and amplifying its self-generation by the activation of factors v, viii, and xi. thrombin has long been a target for the deve ...201020976270
novel isoform of the xenopus tropicalis pka catalytic alpha subunit: an example of alternative splicing.the camp-dependent protein kinase (pka) plays key roles in the control of various aspects of eukaryotic cellular activities by phosphorylating several proteins and is multifunctional in nature. in the case of frog, xenopus tropicalis, a gene encoding the pka catalytic alpha subunit has been identified which encodes a single protein. here we report the occurrence of n-terminal alternative splicing events in x. tropicalis tadpole that, in addition to generating a myristoylatable isoforms, also gen ...201020418193
immortal coils: conserved dimerization motifs of the drosophila ovulation prohormone ovulin.dimerization is an important feature of the function of some proteins, including prohormones. for proteins whose amino acid sequences evolve rapidly, it is unclear how such structural characteristics are retained biochemically. here we address this question by focusing on ovulin, a prohormone that induces ovulation in drosophila melanogaster females after mating. ovulin is known to dimerize, and is one of the most rapidly evolving proteins encoded by the drosophila genome. we show that residues ...201020138215
rhipicephalus (boophilus) microplus: clotting time in tick-infested skin varies according to local inflammation and gene expression patterns in tick salivary glands.ticks deposit saliva at the site of their attachment to a host in order to inhibit haemostasis, inflammation and innate and adaptive immune responses. the anti-haemostatic properties of tick saliva have been described by many studies, but few show that tick infestations or its anti-haemostatic components exert systemic effects in vivo. in the present study, we extended these observations and show that, compared with normal skin, bovine hosts that are genetically susceptible to tick infestations ...201020045690
rickettsia africae, western africa. 201020202453
human ehrlichiosis and anaplasmosis.human ehrlichiosis and anaplasmosis are acute febrile tick-borne diseases caused by various members of the genera ehrlichia and anaplasma (anaplasmataceae). human monocytotropic ehrlichiosis has become one of the most prevalent life-threatening tick-borne disease in the united states. ehrlichiosis and anaplasmosis are becoming more frequently diagnosed as the cause of human infections, as animal reservoirs and tick vectors have increased in number and humans have inhabited areas where reservoir ...201020513551
cuticular plasticization in the tick, amblyomma hebraeum (acari: ixodidae): possible roles of monoamines and cuticular ph.the degree of plasticization of the alloscutal cuticle of a 'hard' (ixodid) tick, amblyomma hebraeum, and a 'soft' (argasid) tick, ornithodoros moubata, was assessed throughout the blood-feeding period. cuticle viscosity was calculated from rate of creep of cuticle under constant load using a maxwell model. feeding-related plasticization (i.e. increased rate of extension under a constant load) occurred in a. hebraeum but not in o. moubata. maxwell viscosity of unfed a. hebraeum cuticle was relat ...201020675552
analysis of amblyomma surveillance data in the caribbean: lessons for future control programmes.amblyomma variegatum, the tropical bont tick (tbt), is the principal vector of heartwater and is associated with dermatophilosis, major causes of losses in animal production and mortality in caribbean livestock. from 1995 to 2007, the caribbean amblyomma programme (cap) supported treatment and surveillance activities in 11 islands of the eastern caribbean with an initial objective of eradicating tbt. in addition to control activities, surveillance data were collected between 1997 and 2006 in a u ...201019833441
the dynamics of questing ticks collected for 164 consecutive months off the vegetation of two landscape zones in the kruger national park (1988-2002). part i. total ticks, amblyomma hebraeum and rhipicephalus decoloratus.despite a large number of studies on tick biology, there is limited information on long- term changes in tick populations. this study thus aimed to assess the long-term population dynamics of questing ixodid ticks in two landscape zones of the kruger national park (knp). questing ixodid ticks were collected in the knp from august 1988 to march 2002 by monthly dragging of the vegetation in three habitats (grassland, woodland and gully) at two sites (nhlowa road and skukuza). findings pertaining t ...201123327204
female ixodid ticks grow endocuticle during the rapid phase of engorgement.lees (proc zool soc lond 121:759-772, 1952) concluded that the ixodid tick ixodes ricinus grows endocuticle during the slow but not during the rapid, phase of engorgement, a conclusion supported by andersen and roepstorff (insect biochem mol biol 35:1181-1188, 2005) for the same species. in this study analysis of dimensional data and cuticle weight measurements from female ixodid ticks (amblyomma hebraeum) were used to test this hypothesis. both approaches showed that endocuticle growth continue ...201120711799
rna interference in ticks.ticks are obligate hematophagous ectoparasites of wild and domestic animals and humans, and are considered to be second worldwide to mosquitoes as vectors of human diseases(1) and the most important vectors affecting cattle industry worldwide(2). ticks are classified in the subclass acari, order parasitiformes, suborder ixodida and are distributed worldwide from arctic to tropical regions(3). despite efforts to control tick infestations, these ectoparasites remain a serious problem for human and ...201121304465
a further insight into the sialome of the tropical bont tick, amblyomma variegatum.ticks--vectors of medical and veterinary importance--are themselves also significant pests. tick salivary proteins are the result of adaptation to blood feeding and contain inhibitors of blood clotting, platelet aggregation, and angiogenesis, as well as vasodilators and immunomodulators. a previous analysis of the sialotranscriptome (from the greek sialo, saliva) of amblyomma variegatum is revisited in light of recent advances in tick sialomes and provides a database to perform a proteomic study ...201121362191
molecular characterization of novel sulfotransferases from the tick, ixodes scapularis.ixodes scapularis, commonly known as the blacklegged or deer tick, is the main vector of lyme disease in the united states. recent progress in transcriptome research has uncovered hundreds of different proteins expressed in the salivary glands of hard ticks, the majority of which have no known function, and include many novel protein families. we recently identified transcripts coding for two putative cytosolic sulfotransferases in these ticks which recognized phenolic monoamines as their substr ...201121708020
crystal structure of thrombin in complex with s-variegin: insights of a novel mechanism of inhibition and design of tunable thrombin inhibitors.the inhibition of thrombin is one of the important treatments of pathological blood clot formation. variegin, isolated from the tropical bont tick, is a novel molecule exhibiting a unique 'two-modes' inhibitory property on thrombin active site (competitive before cleavage, noncompetitive after cleavage). for the better understanding of its function, we have determined the crystal structure of the human α-thrombin:synthetic-variegin complex at 2.4 å resolution. the structure reveals a new mechani ...201122053189
relationships between tick counts and coat characteristics in nguni and bonsmara cattle reared on semiarid rangelands in south africa.indigenous nguni cattle are adapted to the semiarid rangeland and appear to be resistant to ticks; however, the mechanism for tick resistance is yet to be established. to understand tick resistance in cattle, relationships among skin thickness, hair length, coat score, and tick counts were estimated in nguni (n=12) and bonsmara (n=12) heifers on semiarid rangelands of south africa. the tick species observed to infest the heifers were rhipicephalus (boophilus) decoloratus (frequency: 76%), rhipic ...201121890073
First transcriptome of the testis-vas deferens-male accessory gland and proteome of the spermatophore from Dermacentor variabilis (Acari: Ixodidae).Ticks are important vectors of numerous human diseases and animal diseases. Feeding stimulates spermatogenesis, mating and insemination of male factors that trigger female reproduction. The physiology of male reproduction and its regulation of female development are essentially a black box. Several transcriptomes have catalogued expression of tick genes in the salivary glands, synganglion and midgut but no comprehensive investigation has addressed male reproduction and mating. Consequently, a ne ...201121949745
a deep insight into the sialotranscriptome of the gulf coast tick, amblyomma maculatum.saliva of blood sucking arthropods contains compounds that antagonize their hosts' hemostasis, which include platelet aggregation, vasoconstriction and blood clotting; saliva of these organisms also has anti-inflammatory and immunomodullatory properties. perhaps because hosts mount an active immune response against these compounds, the diversity of these compounds is large even among related blood sucking species. because of these properties, saliva helps blood feeding as well as help the establ ...201122216098
identification, phylogenetic analysis and expression profile of an anionic insect defensin gene, with antibacterial activity, from bacterial-challenged cotton leafworm, spodoptera littoralis.defensins are a well known family of cationic antibacterial peptides (amps) isolated from fungi, plants, insects, mussels, birds, and various mammals. they are predominantly active against gram (+) bacteria, and a few of them are also active against gram (-) bacteria and fungi. all insect defensins belonging to the invertebrate class have a consensus motif, c-x₅₋₁₆-c-x₃-c-x₉₋₁₀-c-x₄₋₇-cx₁-c. only seven amps have already been found in different lepidopteran species. no report was published on the ...201122067477
tick infestation patterns in free ranging african buffalo (syncercus caffer): effects of host innate immunity and niche segregation among tick species.ticks are of vast importance to livestock health, and contribute to conflicts between wildlife conservation and agricultural interests; but factors driving tick infestation patterns on wild hosts are not well understood. we studied tick infestation patterns on free-ranging african buffalo (syncercus caffer), asking (i) is there evidence for niche segregation among tick species?; and (ii) how do host characteristics affect variation in tick abundance among hosts? we identified ticks and estimated ...201224533310
simukunin from the salivary glands of the black fly simulium vittatum inhibits enzymes that regulate clotting and inflammatory responses.black flies (diptera: simuliidae) feed on blood, and are important vectors of onchocerca volvulus, the etiolytic agent of river blindness. blood feeding depends on pharmacological properties of saliva, including anticoagulation, but the molecules responsible for this activity have not been well characterized.201222383955
phylogeography and demographic history of amblyomma variegatum (fabricius) (acari: ixodidae), the tropical bont tick.the genetic diversity of amblyomma variegatum (fabricius) from four caribbean islands and five african countries was compared by analyzing the sequences of three gene fragments, two mitochondrial (12srdna and d-loop-dl), and one nuclear (intergenic transcribed spacer 2 [its2]). genetic variability of the its2 dna fragment consisted of only uninformative single nucleotide mutations, and therefore this gene was excluded from further analyses. mitochondrial gene divergences among african population ...201222448720
antiviral effect of the egg wax of amblyomma cajennense (acari: ixodidae).the control of viral infections, especially those caused by influenza viruses, is of great interest in public health. bio prospection has shown the presence of active principles in the hemolymph of arthropods, and in the salivary gland of ticks, and some of these are of interest for the development of new pharmacological drugs. ticks lay their eggs in the environment, and to protect them from desiccation and microbial attack they involve the eggs in a waxy layer produced by an organ known as gen ...201222441939
tick salivary secretion as a source of antihemostatics.ticks are mostly obligatory blood feeding ectoparasites that have an impact on human and animal health. in addition to direct damage due to feeding, some tick species serve as the vectors for the causative agents of several diseases, such as the spirochetes of the genus borrelia causing lyme disease, the virus of tick-borne encephalitis, various rickettsial pathogens or even protozoan parasites like babesia spp. hard ticks are unique among bloodfeeders because of their prolonged feeding period t ...201222564820
the role of nuclear technologies in the diagnosis and control of livestock diseases--a review.nuclear and nuclear-related technologies have played an important role in animal health, particularly in relation to disease diagnosis and characterization of pathogenic organisms. this review focuses primarily on how and where nuclear technologies, both non-isotopic and isotopic methods, have made their impact in the past and where it might be expected they could have an impact in the future. the review outlines the extensive use of radiation attenuation in attempts to create vaccines for a mul ...201222286376
antimicrobial activity in the egg wax of the tick amblyomma hebraeum (acari: ixodidae) is associated with free fatty acids c16:1 and c18:2.untreated eggs of the tick amblyomma hebraeum koch (acari: ixodidae) exhibited antimicrobial activity (ama) against gram-negative but not gram-positive bacteria; eggs denuded of wax by solvent extraction showed no ama. the unfractionated egg wax extract, however, showed ama against gram-positive but not gram-negative bacteria, as also shown by arrieta et al. (exp appl acarol 39: 297-313, 2006). in this study we partitioned the egg wax into various fractions, using a variety of techniques, analyz ...201222692850
molecular characterization of the vitellogenin receptor from the tick, amblyomma hebraeum (acari: ixodidae).we have identified the full-length cdna encoding a vitellogenin receptor (vgr) from the african bont tick amblyomma hebraeum koch (1844). vgrs are members of the low-density lipoprotein receptor superfamily that promote the uptake of the yolk protein vitellogenin (vg), from the haemolymph. the ahvgr (genbank accession no. jx846592) is 5703 bp, and encodes an 1801 aa protein with a 196.5 kda molecular mass following cleavage of a 22 aa signal peptide. phylogenetic analysis indicates that ahvgr is ...201324128609
a comparison between tick species collected in a controlled and control free area on a game ranch in south africa.despite the large number of collection records, there are no recent collections of ixodid ticks of this magnitude in the waterberg area, limpopo province, south africa. free-living ticks on a commercial game farm were obtained by a total of 432 drag-samples in eight sample sites from september 2003 to august 2008. the ticks were collected to establish the difference between tick species and densities associated with acaricide-controlled (semi-intensive) and control-free areas on a game farm in t ...201323718159
detection of lumpy skin disease virus in saliva of ticks fed on lumpy skin disease virus-infected cattle.lumpy skin disease is an economically important disease of cattle that is caused by the lumpy skin disease virus (lsdv), which belongs to the genus capripoxvirus. it is endemic in africa and outbreaks have also been reported in the middle-east. transmission has mostly been associated with blood-feeding insects but recently, the authors have demonstrated mechanical transmission by rhipicephalus appendiculatus as well as mechanical/intrastadial and transstadial transmission by amblyomma hebraeum. ...201323456606
host specialization in ticks and transmission of tick-borne diseases: a review.determining patterns of host use, and the frequency at which these patterns change, are of key importance if we are to understand tick population dynamics, the evolution of tick biodiversity, and the circulation and evolution of associated pathogens. the question of whether ticks are typically host specialists or host generalists has been subject to much debate over the last half-century. indeed, early research proposed that morphological diversity in ticks was linked to host specific adaptation ...201324109592
the influence of interspecific competition and host preference on the phylogeography of two african ixodid tick species.a comparative phylogeographic study on two economically important african tick species, amblyomma hebraeum and hyalomma rufipes was performed to test the influence of host specificity and host movement on dispersion. pairwise amova analyses of 277 mtdna coi sequences supported significant population differentiation among the majority of sampling sites. the geographic mitochondrial structure was not supported by nuclear its-2 sequencing, probably attributed to a recent divergence. the three-host ...201324130813
new data regarding distribution of cattle ticks in the south-western indian ocean islands.recent studies have produced new insight into the origin and distribution of some cattle ticks in the south-western indian ocean islands. rhipicephalus appendiculatus, introduced from tanzania in 2002, is now well established on grande comore but has not yet reached the other islands of the archipelago (mohéli, anjouan and mayotte). only one of the two clades identified in africa has settled so far. amblyomma variegatum, which was not supposed to be able to persist in the antananarivo region (13 ...201324016261
relationship between the prevalence of ectoparasites and associated risk factors in free-range pigs in kenya.a cross-sectional study was undertaken to determine the prevalence of ectoparasites and possible risk factors in free-range pigs from 135 farms of busia district, kenya. three hundred and six pigs were examined for presence of external parasites using standard parasitological methods. data on management practices including housing and history of acaricide spraying were also collected. the ectoparasites found in the pigs were haematopinus suis (96.1%), sarcoptes scabiei (63.7%), and ticks (29.7%) ...201323984085
autocrine/paracrine dopamine in the salivary glands of the blacklegged tick ixodes scapularis.dopamine (da) is known to be the most potent activator of tick salivary secretion, which is an essential component of successful tick feeding. we examined the quantitative changes of catecholamines using a method coupling high-pressure liquid chromatography with electrochemical detection (hplc-ecd). we also investigated the levels of catecholamines conjugated to other molecules utilising appropriate methods to hydrolyse the conjugates. three different biological samples, salivary glands, syngang ...201424503219
ticks and tick-borne viruses from livestock hosts in arid and semiarid regions of the eastern and northeastern parts of kenya.biodiversity and relative abundance of ticks and associated arboviruses in garissa (northeastern) and isiolo (eastern) provinces of kenya were evaluated. ticks were collected from livestock, identified to species, pooled, and processed for virus isolation. in garissa, rhipicephalus pulchellus gerstacker (57.8%) and hyalomma truncatum koch (27.8%) were the most abundant species sampled, whereas r. pulchellus (80.4%) and amblyomma gemma donitz (9.6%) were the most abundant in isiolo. forty-four vi ...201424605478
demonstration of lumpy skin disease virus infection in amblyomma hebraeum and rhipicephalus appendiculatus ticks using immunohistochemistry.lumpy skin disease (lsd) is caused by lumpy skin disease virus (lsdv), a member of the genus capripoxvirus. transmission of the virus has been associated with haematophagous insects such as stomoxys calcitrans as well as aedes and culex species of mosquitoes. recent studies have reported the transmission of the virus by amblyomma hebraeum, rhipicephalus appendiculatus, and rhipicephalus decoloratus ticks and the presence of lsdv in saliva of a. hebraeum and r. appendiculatus ticks. the aim of th ...201424287140
transovarial passage and transmission of lsdv by amblyomma hebraeum, rhipicephalus appendiculatus and rhipicephalus decoloratus.lumpy skin disease (lsd), an acute, sub-acute or inapparent disease of cattle, is caused by lumpy skin disease virus (lsdv), a member of the genus capripoxvirus in the family poxviridae. lsd is characterised by high fever, formation of circumscribed skin lesions and ulcerative lesions on the mucous membranes of the mouth, respiratory and digestive tracts. it is an economically important disease due to the permanent damage to hides, the reduction in productivity and trade restrictions imposed on ...201423975564
evidence of lumpy skin disease virus over-wintering by transstadial persistence in amblyomma hebraeum and transovarial persistence in rhipicephalus decoloratus ticks.lumpy skin disease is a debilitating cattle disease caused by the lumpy skin disease virus (lsdv), belonging to the genus capripoxvirus. epidemics of the disease usually occur in summer, when insect activity is high. limited information is available on how lsdv persists during inter-epidemic periods. transmission of lsdv by mosquitoes such as aedes aegypti has been shown to be mechanical, there is no carrier state in cattle and the role of wildlife in the epidemiology of the disease seems to be ...201423975563
lumpy skin disease: attempted propagation in tick cell lines and presence of viral dna in field ticks collected from naturally-infected cattle.lumpy skin disease (lsd) is of substantial economic importance for the cattle industry in africa and the near and middle east. several insect species are thought to transmit the disease mechanically. recent transmission studies have demonstrated the first evidence for a role of hard (ixodid) ticks as vectors of lumpy skin disease virus (lsdv). the aim of this study was to attempt in vitro growth of the virus in rhipicephalus spp. tick cell lines and investigate in vivo the presence of the virus ...201425468765
molecular detection of tick-borne pathogens in captive wild felids, zimbabwe.the populations of wild felids in africa, of especially lions (panthera leo) and cheetahs (acinonyx jubatus), are declining and the species are classified as vulnerable to extinction by the international union for conservation of nature. as infections with tick-borne pathogens (tbp) can become more of a problem in wild felids, there are relatively few studies on tbp in wild felids in africa and on how these infections might influence population numbers.201425404084
in vitro acaricidal activity of atropa belladonna and its components, scopolamine and atropine, against rhipicephalus (boophilus) microplus.in vitro efficacy of methanolic extract of atropa belladonna and its components scopolamine and atropine was assessed against rhipicephalus (boophilus) microplus. five concentrations of the extract (1.25%, 2.5%, 5%, 10%, and 20%) were used whereas scopolamine and atropine were each tested at 0.1%. in adult immersion test, the extract was lethal to ticks at 20% concentration. the lc50 and lc95 values were determined as 6.875% and 17.306%, respectively. the extract caused a significant reduction ( ...201425516877
first molecular detection of rickettsia africae in ticks from the union of the comoros.rickettsia africae is the agent of african tick bite fever, a disease transmitted by ticks in sub-saharan africa. in union of the comoros, a recent study reported the presence of a rickettsia africae vector but no information has been provided on the circulation of the pathogenic agent in this country.201425245895
are ticks venomous animals?as an ecological adaptation venoms have evolved independently in several species of metazoa. as haematophagous arthropods ticks are mainly considered as ectoparasites due to directly feeding on the skin of animal hosts. ticks are of major importance since they serve as vectors for several diseases affecting humans and livestock animals. ticks are rarely considered as venomous animals despite that tick saliva contains several protein families present in venomous taxa and that many ixodida genera ...201425006341
efficacy of slow-release tags impregnated with aggregation-attachment pheromone and deltamethrin for control of amblyomma variegatum on st. kitts, west indies.amblyomma variegatum is an important cause of morbidity, mortality and economic losses in africa and the west indies. attempts to control and/or eradicate the tick from the caribbean have largely been unsuccessful because of difficulties relating to the biology of the three-host tick and problems with applying acaricides on a regular basis to free-ranging domestic ruminants. while plastic collars impregnated with insecticides are widely and effectively used in companion animals to control extern ...201424731252
history and development of research on wildlife parasites in southern africa, with emphasis on terrestrial mammals, especially ungulates.the history of wildlife parasitology in south africa, and to some extent southern africa, is reviewed, giving a brief overview of the early years and following its development from the founding of the onderstepoort veterinary institute in 1908 until the turn of the century. an emphasis is placed on game species. the main findings on protozoan parasites, including those of carnivores, are presented, starting in the 1890s and leading up to the first decade of the 21st century. important developmen ...201425830101
sensitivity to permethrin in a dermacentor reticulatus population from eastern poland in laboratory study.the action of chemical compounds on the palaearctic tick d. reticulatus (fabricius) (acari: amblyomminae) has been poorly investigated so far. therefore, the effects of application of permethrin on engorged d. reticulatus females have been assessed, and the survival rate for the different developmental stages of the tick species in its non-parasitic phase of the life cycle was determined upon application of the pyrethroid.201424405550
detection and characterization of zoonotic pathogens of free-ranging non-human primates from zambia.wildlife may harbor infectious pathogens that are of zoonotic concern acting as a reservoir of diseases transmissible to humans and domestic animals. this is due to human-wildlife conflicts that have become more frequent and severe over recent decades, competition for the available natural habitats and resources leading to increased human encroachment on previously wild and uninhabited areas.201425358853
spotted fever rickettsia species in hyalomma and ixodes ticks infesting migratory birds in the european mediterranean area.a few billion birds migrate annually between their breeding grounds in europe and their wintering grounds in africa. many bird species are tick-infested, and as a result of their innate migratory behavior, they contribute significantly to the geographic distribution of pathogens, including spotted fever rickettsiae. the aim of the present study was to characterize, in samples from two consecutive years, the potential role of migrant birds captured in europe as disseminators of rickettsia-infecte ...201425011617
gene cloning, expression and immunogenicity of the protective antigen subolesin in dermacentor silvarum.subolesin (4d8), the ortholog of insect akirins, is a highly conserved protective antigen and thus has the potential for development of a broad-spectrum vaccine against ticks and mosquitoes. to date, no protective antigens have been characterized nor tested as candidate vaccines against dermacentor silvarum bites and transmission of associated pathogens. in this study, we cloned the open reading frame (orf) of d. silvarum 4d8 cdna (ds4d8), which consisted of 498 bp encoding 165 amino acid residu ...201424623890
rickettsia africae and candidatus rickettsia barbariae in ticks in israel.dna of several spotted fever group rickettsiae was found in ticks in israel. the findings include evidence for the existence of rickettsia africae and candidatus rickettsia barbariae in ticks in israel. the dna of r. africae was detected in a hyalomma detritum tick from a wild boar and dna of c. rickettsia barbariae was detected in rhipicephalus turanicus and rhipicephalus sanguineus collected from vegetation. the dna of rickettsia massiliae was found in rh. sanguineus and haemaphysalis erinacei ...201424615133
protozoan and bacterial pathogens in tick salivary glands in wild and domestic animal environments in south africa.a total of 7364 ticks belonging to 13 species was collected from 64 game animals (belonging to 11 species) and from 64 livestock animals (cattle and sheep) living in close vicinity at 6 localities in 3 south african provinces (free state, mpumalanga, and limpopo). the geographic distribution of all tick species was congruent with the literature except for haemaphysalis silacea. from each infested host, a maximum of 10 males and 10 females of each tick species were dissected to isolate the saliva ...201424378080
molecular characterization of two vitellogenin genes from the tick, amblyomma hebraeum (acari: ixodidae).we have identified full-length cdnas encoding two vitellogenins (vg) from the african bont tick amblyomma hebraeum koch (1844). vg is a large storage protein that is the precursor to vitellin (vn), the major yolk protein found in eggs. the first vg cdna is 5866 bp long, with a 5715 bp reading frame encoding a 1904 amino acid protein. the second vg cdna is 5963 bp long, with a 5781 open reading frame encoding a 1926 amino acid protein. both proteins possess a short n-terminal signal peptide of 21 ...201425108782
salivary gland degeneration and ovarian development in the rocky mountain wood tick, dermacentor andersoni stiles (acari: ixodidae). i. post-engorgement events.it is well known that female ixodid ticks undergo salivary gland degeneration and the greater part of ovarian development following engorgement. the process has been particularly well studied in amblyomma hebraeum, including the hormonal control of these processes. the purpose of this study, and the second one in this series, is to compare the processes in dermacentor andersoni with those of a. hebraeum. a major difference between the two species is that virgin female d. andersoni feed to a much ...201424973274
salivary gland degeneration and ovary development in the rocky mountain wood tick, dermacentor andersoni stiles (acari: ixodidae). ii. determination of the 'critical weight'.the feeding cycle of female ixodid ticks is divided into preparatory, slow, and rapid feeding phases. when a female amblyomma hebraeum is removed from the host after achieving a minimum size of about 10-13× the unfed weight, various physiological and behavioural changes occur: (a) haemolymph ecdysteroid concentration rises dramatically, (b) the tick does not reattach to the host when given the opportunity, (c) its salivary glands degenerate within about 4 days (if mated) or 8 days (if virgin), a ...201424865927
questing ixodid ticks on the vegetation of sable antelope and multi-herbivore enclosures in thabazimbi.this survey of ixodid ticks was the first to compare the species composition and population dynamics of free-living ticks in intensive, sable antelope breeding enclosures, now commonplace in commercial wildlife ranching in south africa, with those of multi-herbivore enclosures. the species composition, abundance and seasonal abundance of questing ixodid ticks on the vegetation in intensive breeding enclosures for sable antelope (hippotragus niger), on which strategic tick control is practised, w ...201526244584
distribution of endemic and introduced tick species in free state province, south africa.the distributions of endemic tick vector species as well as the presence of species not endemic to free state province, south africa, were determined during surveys or opportunistic collections from livestock, wildlife and vegetation. amongst endemic ticks, the presence of rhipicephalus appendiculatus was confirmed in the north of the province, whilst rhipicephalus decoloratus was collected at 31 localities mostly in the centre and east, and ixodes rubicundus at 11 localities in the south, south ...201526244582
mechanical properties of the cuticle of the tick amblyomma hebraeum (acari: ixodidae).female ticks of the family ixodidae increase their mass up to 100-fold during the 7-10 day feeding period. we determined the material properties of the alloscutal cuticle of female amblyomma hebraeum from the time of moulting through to full engorgement. the material properties of the cuticle were evaluated by a kelvin-voigt analysis of compliance determined from the stretch of loops of cuticle under stress. there was a 3-fold increase in cuticle dry mass during the first 3 weeks post-moult, dur ...201526163583
an update on the ecological distribution of the ixodidae ticks in zimbabwe.in total 7657 ticks were collected from 121 dip tanks in 12 districts representative of zimbabwe's five ecological regions between september 2013 and may 2014. based on morphological traits four genera and 13 species of ticks were identified. amblyomma hebraeum (60.3 %), rhipicephalus microplus (58.7 %), rhipicephalus decoloratus (47.1 %), rhipicephalus appendiculatus (56.2 %), rhipicephalus evertsi evertsi (67.8 %), rhipicephalus (near) punctatus (13.2 %), hyalomma truncatum (38 %) and hyalomma ...201525721256
risk factors associated with clinical dermatophilosis in smallholder sector cattle herds of zimbabwe at the amblyomma variegatum and amblyomma hebraeum interface.a cross-sectional study was conducted to investigate factors for clinical dermatophilosis herd-level positivity in smallholder dip tanks from gokwe (chemawororo, gwanyika), kwekwe (koronika) and chegutu (chivero), zimbabwe, between september 2013 and april 2014. a total of 185 herds were clinically examined for disease and tick infestation. data on herd and potential herd level risk factors were collected using a structured questionnaire. a herd was classified as clinically positive if an animal ...201525465222
bacteria associated with amblyomma cajennense tick eggs.ticks represent a large group of pathogen vectors that blood feed on a diversity of hosts. in the americas, the ixodidae ticks amblyomma cajennense are responsible for severe impact on livestock and public health. in the present work, we present the isolation and molecular identification of a group of culturable bacteria associated with a. cajennense eggs from females sampled in distinct geographical sites in southeastern brazil. additional comparative analysis of the culturable bacteria from an ...201526537602
climate change, biodiversity, ticks and tick-borne diseases: the butterfly effect.we have killed wild animals for obtaining food and decimated forests for many reasons. nowadays, we are burning fossil fuels as never before and even exploring petroleum in deep waters. the impact of these activities on our planet is now visible to the naked eye and the debate on climate change is warming up in scientific meetings and becoming a priority on the agenda of both scientists and policy decision makers. on the occasion of the impact of environmental changes on infectious diseases (iec ...201526835253
molecular detection of zoonotic tick-borne pathogens from ticks collected from ruminants in four south african provinces.ticks carry and transmit a remarkable array of pathogens including bacteria, protozoa and viruses, which may be of veterinary and/or of medical significance. with little to no information regarding the presence of tick-borne zoonotic pathogens or their known vectors in southern africa, the aim of our study was to screen for anaplasma phagocytophilum, borrelia burgdorferi, coxiella burnetii, rickettsia species and ehrlichia ruminantium in ticks collected and identified from ruminants in the easte ...201526227797
modulation of host immunity by tick saliva.next generation sequencing and proteomics have helped to comprehensively characterize gene expression in tick salivary glands at both the transcriptome and the proteome level. functional data are, however, lacking. given that tick salivary secretions are critical to the success of the tick transmission lifecycle and, as a consequence, for host colonization by the pathogens they spread, we thoroughly review here the literature on the known interactions between tick saliva (or tick salivary gland ...201526189360
vector potential and population dynamics for amblyomma inornatum.we studied the natural life cycle of amblyomma inornatum and its vector potential in south texas. this tick is distributed throughout south texas and most of central america. a. inornatum represented 1.91% of the ticks collected by carbon dioxide traps during a study of free-living ticks in the tamaulipan biotic province in south texas. the life cycle of a. inornatum in south texas showed a clear seasonal pattern consistent with one generation per year. nymphs emerged in the spring with a peak i ...201525881916
tick-borne infections in human and animal population worldwide.the abundance and activity of ectoparasites and its hosts are affected by various abiotic factors, such as climate and other organisms (predators, pathogens and competitors) presenting thus multiples forms of association (obligate to facultative, permanent to intermittent and superficial to subcutaneous) developed during long co-evolving processes. ticks are ectoparasites widespread globally and its eco epidemiology are closely related to the environmental conditions. they are obligatory hematop ...201527047089
arachnids of medical importance in brazil: main active compounds present in scorpion and spider venoms and tick saliva.arachnida is the largest class among the arthropods, constituting over 60,000 described species (spiders, mites, ticks, scorpions, palpigrades, pseudoscorpions, solpugids and harvestmen). many accidents are caused by arachnids, especially spiders and scorpions, while some diseases can be transmitted by mites and ticks. these animals are widely dispersed in urban centers due to the large availability of shelter and food, increasing the incidence of accidents. several protein and non-protein compo ...201526273285
molecular characterization of a defensin gene from a hard tick, dermacentor silvarum.ticks are distributed worldwide and considered as vectors of many human diseases. tick defensins, a family of antimicrobial peptides, form the first line of defense against pathogens.201525588982
evidence of transstadial and mechanical transmission of lumpy skin disease virus by amblyomma hebraeum ticks.lumpy skin disease (lsd) is an economically important disease caused by lsd virus (lsdv), a capripoxvirus, characterized by fever and circumscribed skin lesions. it is suspected to be transmitted mechanically by biting flies. to assess the vector potential of amblyomma hebraeum in transmission of lsdv, mechanical/intrastadial and transstadial modes of transmission of the virus by this tick species were investigated. two cattle were artificially infected as sources (donors) of infection to ticks. ...201523702314
how egg case proteins can protect cuttlefish offspring?sepia officinalis egg protection is ensured by a complex capsule produced by the female accessory genital glands and the ink bag. our study is focused on the proteins constituting the main egg case. de novo transcriptomes from female genital glands provided essential databases for protein identification. a proteomic approach in sds-page coupled with ms unveiled a new egg case protein family: sepecps, for sepia officinalis egg case proteins. n-glycosylation was demonstrated by pas staining sds-pa ...201526168161
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