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expression of nicotinic acetylcholine receptor subunits from parasitic nematodes in caenorhabditis elegans.the levamisole-sensitive nicotinic acetylcholine receptor present at nematode neuromuscular junctions is composed of multiple different subunits, with the exact composition varying between species. we tested the ability of two well-conserved nicotinic receptor subunits, unc-38 and unc-29, from haemonchus contortus and ascaris suum to rescue the levamisole-resistance and locomotion defects of caenorhabditis elegans strains with null deletion mutations in the unc-38 and unc-29 genes. the parasite ...201526747395
examination of commercially available copper oxide wire particles in combination with albendazole for control of gastrointestinal nematodes in lambs.control of gastrointestinal nematodes (gin) remains a critical issue due to the prevalence of anthelmintic resistance. the objective of the experiment was to determine the efficacy of copper oxide wire particles (cowp) from three commercial sources and a combination of cowp and albendazole to control gin and/or haemonchus contortus in lambs. naturally infected katahdin lambs in early june 2014 and 2015 were randomly assigned to receive no cowp (con; n=9 and 12) or 2g cowp in a gel capsule as cop ...201626790729
identification of differentially expressed proteins between free-living and activated third-stage larvae of haemonchus contortus.the disease caused by haemonchus contortus, a blood-feeding nematode of small ruminants, is of major economic importance worldwide. the infective third-stage larva (l3) of this nematode is enclosed in a second cuticle. once the l3 is ingested by the host, the outer cuticle undergoes an exsheathment process that marks the transition from the free-living stage to the parasitic stage. this study explored the changes in protein expression relative to this transition. proteins extracted from free liv ...201626790740
lack of efficacy of monepantel against trichostrongylus colubriformis in sheep in brazil.multiple drug resistance of nematodes against anthelmintics has become one of the most important economic problems in sheep production worldwide. the aim of this experiment was to evaluate the efficacy of monepantel (2.5mg/kg) against gastrointestinal nematodes in fecal egg count reduction test (fecrt) and controlled efficacy test (ct) in naturally infected sheep. we used 30 sheep for the fecrt and 20 sheep for the ct, equally divided into control and treated groups. in the fecrt, the reduction ...201626801587
chemical structures of plant hydrolyzable tannins reveal their in vitro activity against egg hatching and motility of haemonchus contortus nematodes.the use of synthetic drugs against gastrointestinal nematodes of ruminants has led to a situation where resistance to anthelmintics is widespread, and there is an urgent need for alternative solutions for parasite control. one promising approach is to use polyphenol-rich bioactive plants in animal feeds as natural anthelmintics. in the present work, the in vitro activity of a series of 33 hydrolyzable tannins (hts) and their hydrolysis product, gallic acid, against egg hatching and motility of l ...201626807485
in vitro and in vivo nematocidal activity of allium sativum and tagetes erecta extracts against haemonchus contortus.in the mexican ethno-medicine, a number of plants have shown a successful anthelmintic activity. this fact could be crucial to identify possible green anti-parasitic strategies against nematodes affecting animal production. this research evaluated the in vitro and in vivo nematocidal effects of two single and combined plant extracts: bulbs of allium sativum (n-hexane) and flowers of tagetes erecta (acetone). the in vivo assay evaluated the administration of extracts either individually or combin ...201526809911
characterisation of p-glycoprotein-9.1 in haemonchus contortus.the existence nematodes of veterinary importance such as haemonchus contortus resistant to anthelmintic drugs, including the macrocyclic lactones, has become a major concern in animal health. macrocyclic lactone resistance in h. contortus seems to be multigenic including the active efflux of these drugs by p-glycoproteins, members of the abc transporter family, present in this parasite. the goals of the present work were to determine the activity of h. contortus p-glycoprotein 9.1 (hco-pgp-9.1) ...201626822677
experimental infection of calves with haemonchus placei and haemonchus contortus: assessment of parasitological parameters.the present study evaluated the viability and possible effects of haemonchus contortus infections in experimentally prime infected calves, comparing them to infections by haemonchus placei. ten male holstein newborns were used. all calves were individually weighed for subsequent group formation, in which two animals were kept as a control group, inoculated with water (gi); four animals were inoculated with 10,000 third stage (l3) haemonchus contortus larvae (gii); and the remaining four calves w ...201626827856
in vitro susceptibility of ten haemonchus contortus isolates from different geographical origins towards acetone:water extracts of two tannin rich plants.the aim of the study was to examine the variation in the in vitro susceptibility of ten haemonchus contortus isolates from different geographical origins using respective egg hatch assays (eha) with acetone:water extracts of two tannin containing plants, chimay (acacia pennatula) and sainfoin (onobrychis viciifolia). fresh eggs were incubated in pbs with different concentrations of each extract (0, 600, 1200, 2400, 3600, 5000 and 8000 μg/ml pbs). additional concentrations were tested for o. vici ...201626827861
use of fluorescent lectin binding to distinguish eggs of gastrointestinal nematode parasites of sheep.the binding of a panel of 19 lectins to carbohydrates on the eggs of economically important nematode parasites of sheep has been assessed as the basis of a rapid test to distinguish parasite eggs, at least at the genus level. a total of six lectins can be used to identify eggs of six nematode parasites: peanut agglutinin (pna) for haemonchus contortus; lens culinaris agglutinin (lca) for teladorsagia sp; aleuria aurantia agglutinin (aal) for trichostrongylus sp; psophocarpus tetragonolobus‑ii (p ...201626827865
reconstruction of the insulin-like signalling pathway of haemonchus contortus.in the present study, we reconstructed the insulin/insulin-like growth factor 1 signalling (iis) pathway for haemonchus contortus, which is one of the most important eukaryotic pathogens of livestock worldwide and is related to the free-living nematode caenorhabditis elegans.201626842675
molecular characterization of the haemonchus contortus phosphoinositide-dependent protein kinase-1 gene (hc-pdk-1).phosphoinositide-dependent protein kinase-1 (pdk-1), which functions downstream of phosphoinositide 3-kinase (age-1) and activates protein kinases of the agc family, plays critical roles in regulating biology processes, such as metabolism, growth, development and survival. in the free-living nematode caenorhabditis elegans, pdk-1 is a key component of the insulin-like signalling pathway, regulating the entry into and exit from dauer (arrested development). although it is proposed that similar mo ...201626842781
the effect of helminth infection on the microbial composition and structure of the caprine abomasal microbiome.haemonchus contortus is arguably the most injurious helminth parasite for small ruminants. we characterized the impact of h. contortus infection on the caprine abomasal microbiome. fourteen parasite naive goats were inoculated with 5,000 h. contortus infective larvae and followed for 50 days. six age-matched naïve goats served as uninfected controls. reduced bodyweight gain and a significant increase in the abosamal ph was observed in infected goats compared to uninfected controls. infection als ...201626853110
first report of multiple anthelmintic resistance in nematodes of sheep in colombia.this study aimed to report the presence of parasites resistant to the most used anthelmintic drugs in sheep in colombia. four farms (denominated farm 1, 2, 3 and 4) were selected where the animals were not treated with anthelmintics for two months before the trial. animals with faecal egg count (fec) above 150 and of different ages were allocated into six groups, each consisting of at least 5 animals. the drugs and dosages used were: ivermectin 1% (0.2 mg/kg), albendazole 25% (5 mg/kg), fenbenda ...201626871489
comparative efficacy and toxic effects of carvacryl acetate and carvacrol on sheep gastrointestinal nematodes and mice.carvacrol is a compound isolated from some essential oils. it has been reported to possess anthelmintic activity. acetylation of this monoterpene has been proposed as a potential way to reduce the toxicity and enhance the pharmacological effects of carvacrol. this study aimed to evaluate the effect of carvacryl acetate (ca) using in vitro and in vivo assays with gastrointestinal nematodes of small ruminants. the egg hatching test (eht), larval development test (ldt) and adult worm motility (awm) ...201626872928
impact of the post-weaning nutritional history on the response to an experimental haemonchus contortus infection in creole goats and black belly sheep.in small ruminants, the response against gastrointestinal nematode (gin) infections is influenced not only by the host genotype and the physiological stage but also by environmental factors, particularly the nutritional status at the time of infection. in this study we evaluated the long-term effect and the interaction between the host species and the nutritional history on the response to gin infection in two animal models differing in their phenotypic growth and their level of gin resistance: ...201626872933
famacha(©) scores history of sheep characterized as resistant/resilient or susceptible to h. contortus in artificial infection challenge.with the aim of validating the famacha(©) as a method for phenotypic selection of sheep resistant/resilient to gastrointestinal nematodes, 27 suffolk ewes with known famacha(©) score histories were experimentally infected with 25,000 larvae of haemonchus contortus. from the day of infection (day 0) to 60 days post-infection, at intervals of 7-15 days, ewes were evaluated for packed cell volume (pcv) and fecal egg counts (fec). a statistically significant increase (p<0.05) in fec occurred between ...201626872936
in vitro assessment of the anthelmintic activity of hedysarum carnosum desf. at different phenological stages and from six locations in tunisia.gastrointestinal nematodes are compromising productivity of grazing sheep and goats. therefore, scientists have been looking for cost-effective alternative options. forage legumes (fabacea family) contain tannins that could improve livestock performance and their health as well. the present study aimed to (i) determine the in vitro anthelmintic (ah) activity of 19 acetonic extracts of hedysarum carnosum desf on haemonchus contortus by a larval exsheathment assay (lea); (ii) test the anthelmintic ...201626935783
evaluation of recombinant multi-epitope proteins for diagnosis of goat schistosomiasis by enzyme-linked immunosorbent assay.schistosomiasis is a huge threat to human and animal health. apart from bovines, goats play an important role in the transmission of schistosomiasis in some endemic areas of china. an accessible, quality-assured goat schistosomiasis diagnostic technique is needed. recently, our laboratory identified two recombinant diagnostic antigens, sjpgm and sjrad23 via an immuno-proteomic method. the application of these two recombinant antigens to develop a higher sensitivity and specificity technique for ...201626955957
pathology of haemonchus contortus in new world camelids in the southeastern united states: a retrospective review.most small ruminant farms in tropical climates are plagued by haemonchus contortus, a hematophagous, abomasal parasite. heavy burdens of this parasite can cause anemia, hypoproteinemia, weight loss, and mortality in susceptible animals. haemonchus contortus is becoming a major health concern in new world camelids as well, namely llamas (llama glama) and alpacas (vicugna pacos), yet little research has been conducted regarding its prevalence or pathology in these species. herein, we present a ret ...201626965230
larval development assays reveal the presence of sub-populations showing high- and low-level resistance in a monepantel (zolvix®)-resistant isolate of haemonchus contortus.resistance to the amino-acetonitrile derivative monepantel has been reported in several species of gastrointestinal nematodes over recent years. we were interested in the use of in vitro assays with free-living worm life-stages to detect resistance to this drug. we therefore used larval development and larval migration assays to examine dose response relationships for the drug against two susceptible and one resistant isolate of haemonchus contortus. the resistant isolate was established by labo ...201626995725
phenotypic assessment of the ovicidal activity of monepantel and monepantel sulfone on gastro-intestinal nematode eggs.the in vitro ovicidal activity of the amino acetonitrile derivative, monepantel (mptl) and its active metabolite monepantel sulfone (mptl-so2) were assessed against a number of commercially important nematode species of ruminants, namely teladorsagia circumcincta, haemonchus contortus and trichostrongylus axei. an egg hatch test (eht) was used to make the assessment of both drug sensitive and drug resistant isolates. both mptl and mptl-so2 showed moderate ovicidal activity in vitro against all o ...201626995727
the 'toolbox' of strategies for managing haemonchus contortus in goats: what's in and what's out.a dynamic and innovative approach to managing the blood-consuming nematode haemonchus contortus in goats is critical to crack dependence on veterinary anthelmintics. h. contortus management strategies have been the subject of intense research for decades, and must be selected to create a tailored, individualized program for goat farms. through the selection and combination of strategies from the toolbox, an effective management program for h. contortus can be designed according to the unique con ...201626995728
albendazole in environment: faecal concentrations in lambs and impact on lower development stages of helminths and seed germination.albendazole (abz), widely used benzimidazole anthelmintic, administered to animals enters via excrements into environment and may impact non-target organisms. moreover, exposure of lower development stages of helminths to anthelmintics may also encourage the development of drug-resistant strains of helminths. in present project, the kinetics of abz (10 mg kg(-1) p.o.) and its metabolite (abz.so, abzso2) elimination in faeces from treated texel lambs were studied using uhplc/ms/ms with the aim to ...201626996913
effectiveness of ivermectin and albendazole against haemonchus contortus in sheep in west java, indonesia.administering a half dose of an anthelmintic is a simple method for detecting resistance in parasites infesting small ruminants. when a single anthelmintic fails in native sheep from indonesia, a combination of anthelmintics from different chemical classes with different modes of action are administered as an alternative parasite-control strategy. this study compared the anthelmintic efficacy of ivermectin (ivm) and albendazole (abz) given either separately as a single dose or half dose or co-ad ...201627019686
anthelmintic activity of selected ethno-medicinal plant extracts on parasitic stages of haemonchus contortus.parasitic roundworms (nematodes) cause substantial morbidity and mortality in livestock animals globally, and considerable productivity losses to farmers. the control of these nematodes has relied largely on the use of a limited number of anthelmintics. however, resistance to many of these these anthelmintics is now widespread, and, therefore, there is a need to find new drugs to ensure sustained and effective treatment and control into the future.201627036205
explaining premunition with kin selection using haemonchus contortus.premunition is the state in a disease where an existing infection protects the host from reinfection with the same species. the cause of premunition is not clearly understood. in this study, we hypothesized that kin-selection might be a contributing factor in premunition. to test this theory, sheep were infected either once with a linguiform or smooth vulval morphotype of haemonchos contortus, twice with the same morphotype or twice with different morphotypes. all infections resulted in a simila ...201627045365
clinicopathological studies of gastrointestinal tract disorders in sheep with parasitic infection.this study was envisaged to elucidate the parasitological aspects of gastrointestinal tract (git) disorders of sheep.201527046991
cross antigenicity of immunodominant polypeptides of somatic antigen of oesophagostomum columbianum with other helminths by western blotting.oesophagostomum columbianum in small ruminants in india is found as mixed infection commonly in sheep and goat. haemonchus contortus, an abomasal nematode is found as concurrent infection with it. eggs of haemonchus and o. columbianum cannot be easily distinguished. diagnosis of o. columbianum may only be possible if a non-cross antigenic polypeptide was available for immunodiagnosis.201527047030
effect of tanniferous leaf meal based multi-nutrient blocks on feed intake, hematological profile, immune response, and body weight changes in haemonchus contortus infected goats.the aim was to assess the effect of multi nutrient block (mnb) supplementation with and without tanniferous leaf meal mixture on feed intake, hematological profile, immune response, and body weight changes of goats that were experimentally infected with haemonchus contortus.201527047137
pathomorphological and microbiological studies in sheep with special emphasis on gastrointestinal tract disorders.the present study was envisaged to elucidate the pathomorphological and microbiological aspects of gastrointestinal tract (git) disorders of sheep/lambs.201527047191
in vitro anthelmintic efficacy of inhibitors of phosphoethanolamine methyltransferases in haemonchus contortus.the essential phosphobase methylation pathway for synthesis of phosphocholine is unique to nematodes, protozoa and plants, and thus an attractive antiparasitic molecular target. herein, we screened compounds from the national cancer institute (developmental therapeutics program open chemical repository) for specific inhibitory activity against haemonchus contortus phosphoethanolamine methyltransferases (hcpmt1 and hcpmt2), and tested candidate compounds for anthelmintic activity against adult an ...201627054063
early il-4 gene expression in abomasum is associated with resistance to haemonchus contortus in hair and wool sheep breeds.early immune events associated with reduced larval burden remain unclear in parasite-resistant breeds of sheep. therefore, our objective was to determine breed differences in immune-related gene expression following infection with h. contortus. gene expression in abomasal tissue and mucosa and in abomasal lymph nodes (aln) was measured in 24 st. croix (hair) lambs and 24 dorset x (finn-rambouillet) (wool) lambs at 0 (uninfected), 3, 5 and 7 days after infection with 10 000 l3 h. contortus larvae ...201627059919
effect of condensed tannins supplementation through leaf meal mixture on voluntary feed intake, immune response and worm burden in haemonchus contortus infected sheep.the study was carried out to assess the effect of condensed tannins (ct) supplementation through leaf meal mixture (lmm) on feed intake, humoral [immunoglobulin g (igg)], cell mediated immune response (cmi) and faecal egg counts in haemonchus contortus infected sheep. eighteen sheep were randomly divided into three groups (negative control-nc, infected control-c and infected treatment-t) of six animals in each group in a completely randomized block design for a period of 90 days. twelve h. conto ...201627065606
effect of anthelmintic treatment strategy on strongylid nematode species composition in grazing lambs in scotland.refugia based anthelmintic protocols aim to reduce the rate of development of anthelmintic resistance in gastrointestinal nematodes (gin). previous studies have illustrated the impact of different drenching regimes on drug efficacy and animal growth; however, the impact on nematode populations has yet to be characterised within natural infections. this study investigated the changes in species composition of gin throughout the grazing season, following implementation of four different ivermectin ...201627067011
correlation of polyphenolic content with radical-scavenging capacity and anthelmintic effects of rubus ulmifolius (rosaceae) against haemonchus contortus.phenolic content, antioxidant and anthelmintic activities of herbal extracts are of particular interest to drug industry; plant extracts with significant anthelmintic activity have the potential to be used as alternatives to conventional chemical drugs. in the present study, rubus ulmifolius fruit extracts obtained using solvents of increasing polarity (water, methanol, chloroform and hexane) were examined for their antioxidant and anthelmintic activities in correlation with their polyphenolic c ...201627084470
excretory/secretory products of adult haemonchus contortus and teladorsagia circumcincta which increase the permeability of caco-2 cell monolayers are neutralised by antibodies from immune hosts.the onset of abomasal pathophysiology due to parasitism coincides with the presence of adult worms in the lumen, implicating worm excretory/secretory (es) products acting on the surface mucosa. caco-2 cell monolayers were grown to confluence on transwell plates and exposed on the apical side to es products of adult haemonchus contortus and teladorsagia circumcincta. es products of both species significantly (p<0.001) reduced transepithelial electrical resistance after 2h to 81.1±1.0% and 82.9±1. ...201627084480
potential anthelmintic activity of pelargonium endlicherianum fenzl.the decoction prepared from the roots of pelargonium endlicherianum fenzl. has been used for the treatment of gastrointestinal parasitism in small ruminants in turkish folk medicine.201627130640
effects of in vitro exposure to ivermectin and levamisole on the expression patterns of abc transporters in haemonchus contortus larvae.this study investigated the interaction of atp binding cassette (abc) transport proteins with ivermectin (ivm) and levamisole (lev) in larvae of susceptible and resistant isolates of haemonchus contortus in vitro by measuring transcription patterns following exposure to these anthelmintics. furthermore, we studied the consequences of drug exposure by measuring the sensitivity of l3 to subsequent exposure to higher drug concentrations using larval migration assays. the most highly transcribed tra ...201627164439
abc-b transporter genes in dirofilaria immitis.dirofilaria immitis is a filarial nematode causing infection and heartworm disease in dogs and other canids, cats, and occasionally in humans. prevention with macrocyclic lactones (ml) is recommended during the mosquito transmission season. recently, ml resistance has been reported. abc-b transporter genes are thought to be involved in the mechanism of ml resistance in other nematodes. this study aimed to identify all the abc-b transporter genes in d. immitis using as a reference the ndi.2.2 d. ...201627164440
analysis of putative resistance gene loci in uk field populations of haemonchus contortus after 6years of macrocyclic lactone use.sheep farmers in the uk rely on strategic anthelmintic use to treat and control gastrointestinal roundworms in their flocks. however, resistance to these drugs is now widespread and threatens the sustainability of sheep production. the mechanisms underlying resistance to the most commonly used class, the macrocyclic lactones, are not known and sensitive diagnostic tools based on molecular markers are not currently available. this prohibits accurate surveillance of resistance or assessment of str ...201627179994
possible mechanisms of host resistance to haemonchus contortus infection in sheep breeds native to the canary islands.haemonchus contortus appears to be the most economically important helminth parasite for small ruminant production in many regions of the world. the two sheep breeds native to the canary islands display distinctly different resistant phenotypes under both natural and experimental infections. canaria hair breed (chb) tends to have significantly lower worm burden and delayed and reduced egg production than the susceptible canaria sheep (cs). to understand molecular mechanisms underlying host resis ...201627197554
knockdown of phosphoethanolamine transmethylation enzymes decreases viability of haemonchus contortus.the phosphobase methylation pathway, in which phosphoethanolamine n-methyltransferases (pmts) successively catalyze the methylation of phosphoethanolamine to phosphocholine, is essential in the free-living nematode caenorhabditis elegans. two pmt-encoding genes (hcpmt1 and hcpmt2) cloned from haemonchus contortus have been shown, by in vitro assays, to possess enzymatic characteristics similar to those of c. elegans pmts, but their physiological significance in h. contortus is yet to be elucidat ...201627198768
in vitro and in vivo action of piptadenia viridiflora (kunth) benth against haemonchus contortus in sheep.anthelminthic resistant populations of haemonchus contortus are a major problem in sheep rearing, but plant extracts may offer viable alternative treatments. in our preliminary studies, piptadenia viridiflora was frequently selected by sheep grazing in the cerrado. the present research evaluated its in vitro and in vivo anthelmintic activity. the hplc chromatograms of p. viridiflora aqueous extract (ae) and ethanolic extract (ee) showed the presence of flavonoids. the total condensed tannin (pro ...201627198776
potential role for mucosal iga in modulating haemonchus contortus adult worm infection in sheep.haemonchus contortus (h. contortus) is a haematophagous parasite which causes important economic losses in small ruminants. on the island of gran canaria, two sheep breeds coexist which differ in their susceptibility to the infection with h. contortus; the resistant canaria hair breed (chb) sheep and the susceptible canaria sheep (cs) breed. the major target of resistance mechanisms in chb sheep are directed to the adult parasite stage, reducing the worm burden, and decreased length and fecundit ...201627198794
evidence from two independent backcross experiments supports genetic linkage of microsatellite hcms8a20, but not other candidate loci, to a major ivermectin resistance locus in haemonchus contortus.haemonchus contortus is the leading parasitic nematode species used to study anthelmintic drug resistance. a variety of candidate loci have been implicated as being associated with ivermectin resistance in this parasite but definitive evidence of their importance is still lacking. we have previously performed two independent serial backcross experiments to introgress ivermectin resistance loci from two h. contortus ivermectin-resistant strains - mhco4(wrs) and mhco10(cavr) - into the genetic bac ...201627216082
haemonchus contortus excretory and secretory proteins (hcesps) suppress functions of goat pbmcs in vitro.excretory and secretory products (esps) of nematode contain various proteins which are capable of inducing the instigation or depression of the host immune response and are involved in the pathogenesis of the worms. in the present study, haemonchus contortus excretory and secretory products (hcesps) were collected from the adult worms. binding of hcesps to goat peripheral blood mononuclear cells (pbmcs) was confirmed by immune-fluorescence assay. effects of the hcesps on cytokine production, cel ...201627229536
evolution and biogeography of haemonchus contortus: linking faunal dynamics in space and time.history is the foundation that informs about the nuances of faunal assembly that are essential in understanding the dynamic nature of the host-parasite interface. all of our knowledge begins and ends with evolution, ecology and biogeography, as these interacting facets determine the history of biodiverse systems. these components, relating to haemonchus, can inform about the complex history of geographical distribution, host association and the intricacies of host-parasite associations that are ...201627238001
genetic diversity and population structure of haemonchus contortus.haemonchus contortus is one of the most successful and problematic livestock parasites worldwide. from its apparent evolutionary origins in sub-saharan africa, it is now found in small ruminants in almost all regions of the globe, and can infect a range of different domestic and wildlife artiodactyl hosts. it has a remarkably high propensity to develop resistance to anthelmintic drugs, making control increasingly difficult. the success of this parasite is, at least in part, due to its extremely ...201627238002
the biochemistry of haemonchus contortus and other parasitic nematodes.different life cycle stages of haemonchus contortus adapt to different ecosystems. this adaptation is accompanied by alterations in gene transcription and expression associated with the energy, amino acid, nitrogen, lipid and/or nucleic acid metabolism of the respective stages. for example, the aerobic metabolism of larvae depends on an efficient citric acid cycle, whereas the anaerobic metabolism of adults requires glycolysis, resulting in the production of volatile fatty acids, such as acetic ...201627238003
the pathophysiology, ecology and epidemiology of haemonchus contortus infection in small ruminants.the parasitic nematode haemonchus contortus occurs commonly in small ruminants, and it is an especially significant threat to the health and production of sheep and goats in tropical and warm temperate zones. the main signs of disease (haemonchosis) relate to its blood-feeding activity, leading to anaemia, weakness and frequently to deaths, unless treatment is provided. due to the high biotic potential, large burdens of h. contortus may develop rapidly when environmental conditions favour the fr ...201627238004
the identification of haemonchus species and diagnosis of haemonchosis.diagnosis is often equated with identification or detection when discussing parasitic diseases. unfortunately, these are not necessarily mutually exclusive activities; diseases and infections are generally diagnosed and organisms are identified. diagnosis is commonly predicated upon some clinical signs; in an effort to determine the causative agent, identification of genera and species is subsequently performed. both identification and diagnosis play critical roles in managing an infection, and ...201627238005
diagnosis, treatment and management of haemonchus contortus in small ruminants.haemonchus contortus is a highly pathogenic, blood-feeding nematode of small ruminants, and a significant cause of mortalities worldwide. haemonchosis is a particularly significant threat in tropical, subtropical and warm temperate regions, where warm and moist conditions favour the free-living stages, but periodic outbreaks occur more widely during periods of transient environmental favourability. the clinical diagnosis of haemonchosis is based mostly on the detection of anaemia in association ...201627238006
interactions between nutrition and infections with haemonchus contortus and related gastrointestinal nematodes in small ruminants.interactions between host nutrition and feeding behaviour are central to understanding the pathophysiological consequences of infections of the digestive tract with parasitic nematodes. the manipulation of host nutrition provides useful options to control gastrointestinal nematodes as a component of an integrated strategy. focussed mainly on the haemonchus contortus infection model in small ruminants, this chapter (1) illustrates the relationship between quantitative (macro- and micro-nutrients) ...201627238007
immunity to haemonchus contortus and vaccine development.sheep are capable of developing protective immunity to haemonchus contortus through repeated exposure to this parasite, although this immune protection is the result of a complex interaction among age, gender, physiological status, pregnancy, lactation, nutrition and innate and adaptive immunity in the host animal. there are multiple effectors of the protective immune response, which differ depending on the developmental stage of the parasite being targeted, and our understanding of the effector ...201627238008
anthelmintic resistance in haemonchus contortus: history, mechanisms and diagnosis.haemonchus contortus has shown a great ability to develop resistance to anthelmintic drugs. in many instances, resistance has appeared less than 10years after the introduction of a new drug class. field populations of this species now show resistance to all major anthelmintic drug classes, including benzimidazoles (bzs), imidazothiazoles and macrocyclic lactones. in addition, resistance to the recently introduced amino-acetonitrile derivative class (monepantel) has already been reported. the exi ...201627238009
haemonchus contortus: applications in drug discovery.haemonchus contortus is an important pathogen of small ruminants and is therefore a crucially important target for anthelmintic chemotherapy. its large size and fecundity have been exploited for the development of in vitro screens for anthelmintic discovery that employ larval and adult stages in several formats. the ability of the parasite to develop to the young adult stage in mongolian jirds (meriones unguiculatus) provides a useful small animal model that can be used to screen compounds prior ...201627238010
gaining insights into the pharmacology of anthelmintics using haemonchus contortus as a model nematode.progress made in understanding pharmacokinetic behaviour and pharmacodynamic mechanisms of drug action/resistance has allowed deep insights into the pharmacology of the main chemical classes, including some of the few recently discovered anthelmintics. the integration of pharmaco-parasitological research approaches has contributed considerably to the optimization of drug activity, which is relevant to preserve existing and novel active compounds for parasite control in livestock. a remarkable am ...201627238011
understanding haemonchus contortus better through genomics and transcriptomics.parasitic roundworms (nematodes) cause substantial mortality and morbidity in animals globally. the barber's pole worm, haemonchus contortus, is one of the most economically significant parasitic nematodes of small ruminants worldwide. although this and related nematodes can be controlled relatively well using anthelmintics, resistance against most drugs in common use has become a major problem. until recently, almost nothing was known about the molecular biology of h. contortus on a global scal ...201627238012
haemonchus contortus: genome structure, organization and comparative genomics.one of the first genome sequencing projects for a parasitic nematode was that for haemonchus contortus. the open access data from the wellcome trust sanger institute provided a valuable early resource for the research community, particularly for the identification of specific genes and genetic markers. later, a second sequencing project was initiated by the university of melbourne, and the two draft genome sequences for h. contortus were published back-to-back in 2013. there is a pressing need f ...201627238013
functional genomics tools for haemonchus contortus and lessons from other helminths.the availability of genome and transcriptome data for parasitic nematodes, including haemonchus contortus, has highlighted the need to develop functional genomics tools. comparative genomic analysis, particularly using data from the free-living nematode caenorhabditis elegans, can help predict gene function. reliable approaches to study function directly in parasitic nematodes are currently lacking. however, gene knockdown by rna interference (rnai) is being successfully used in schistosome and ...201627238014
acquired tolerance to ivermectin and moxidectin after drug selection pressure in the nematode caenorhabditis elegans.ivermectin and moxidectin are the most widely administered anthelmintic macrocyclic lactones (mls) to treat human and animal nematode infections. their widespread and frequent use has led to a high level of resistance to these drugs. although they have the same mode of action, differences in terms of selection for drug resistance have been reported. our objective was to study and compare changes occurring upon ivermectin or moxidectin selection in the model nematode caenorhabditis elegans c. ele ...201627246778
benzimidazole resistance in haemonchus contortus recovered from farmed red deer.thirty haemonchus contortus male worms were collected from farmed red deer yearlings in order to determine whether routine administration of albendazole for a long-term period (17 years) could select anthelmintic resistance. pcr-rflp method based on single-nucleotide polymorphism of codon 200 in isotype 1 ß-tubulin gene (phe200tyr) was applied. the results showed a significant frequency of either the resistant allele (85 %) or the homozygous resistant genotype (70 %). by chi-square test, hardy-w ...201627249966
a hydroalcoholic extract from paullinia pinnata l. roots exerts anthelmintic activity against free-living and parasitic nematodes.paullinia pinnata is a medicinal plant traditionally used in west africa against a wide range of diseases including soil-transmitted helminthiases. in this study, a hydroethanolic root extract was investigated for its phytochemical composition and in vitro activity against the free-living nematode caenorhabditis elegans as well as the larval stages of the parasitic helminths ancylostoma caninum, haemonchus contortus, toxocara cati, and trichuris vulpis.lc-ms analysis of the ethanol-water (1 : 1) ...201627286336
selenophene and thiophene-core estrogen receptor ligands that inhibit motility and development of parasitic stages of haemonchus contortus.parasitic worms represent a substantial disease burden in animals and humans worldwide. the control of parasitic roundworms (nematodes) relies heavily on the use of anthelmintic drugs. however, widespread drug resistance in nematodes seriously compromises the effectiveness of many anthelmintics around the world. thus, there is a need to discover new drugs, with unique modes of action, against parasites.201627306029
microsatellite marker analysis of haemonchus contortus populations from pakistan suggests that frequent benzimidazole drug treatment does not result in a reduction of overall genetic diversity.the impact of drug selection pressure on the overall genetic diversity of parasitic nematode populations in the field is poorly understood. in this study, we address this issue for the small ruminant parasite haemonchus contortus in the punjab, pakistan. this region provides an opportunity to compare h. contortus populations that have been subjected to a prolonged period of frequent benzimidazole drug treatments on government farms with parasite populations that have been exposed to little or no ...201627316714
transmembrane protein 147 (tmem147): another partner protein of haemonchus contortus galectin on the goat peripheral blood mononuclear cells (pbmc).recombinant galectins of male and female haemonchus contortus (rhco-gal-m/f) have been recognized as significant regulators of the functions of goat peripheral blood mononuclear cells (pbmc). in previous research, transmembrane protein 63a (tmem63a) was identified as a partner protein in the regulation associated with h. contortus infection. however, in the identification of binding partners for galectins of male and female h. contortus (hco-gal-m/f) by yeast two-hybrid (yth) screening, it was f ...201627337943
evaluation of anthelmintic activity of biologically synthesized silver nanoparticles against the gastrointestinal nematode, haemonchus contortus.the present study focuses on the in vitro anthelmintic activity of silver nanoparticles (agnps) synthesized using the aqueous extract of azadirachta indica against haemonchus contortus. the synthesized agnps were characterized by ultraviolet-visible (uv-vis) spectrophotometry, scanning electron microscopy (sem), transmission electron microscopy (tem) and x-ray diffraction (xrd) studies. the uv-vis spectrum exhibited a sharp peak at 420 nm, which was validated by electron microscopy, indicating t ...201627374616
histochemical study of the effects on abomasal mucins of haemonchus contortus or teladorsagia circumcincta infection in lambs.previously, chemical analysis of gastric fundic mucin showed that infection of sheep with haemonchus contortus or teladorsagia circumcincta changed the proportions of monosaccharides and decreased terminal mucin fucosylation and sialylation. to identify the effects of these parasites on the two mucin-secreting cell lineages, fundic and antral tissues were collected for histochemistry from 69 lambs aged from 3-4 to 9-10 months-of-age which had received a single infection of either h. contortus or ...201627387375
in vitro and in vivo anthelmintic activity of murraya koenigii against gastro-intestinal nematodes of sheep.the present study have been conducted to evaluate the anthelmintic activity of crude aqueous and crude methanolic leaf extracts of murraya koenigii. infection of ruminants with gastro-intestinal (gi) parasite has become a worldwide problem. the parasite causes economic losses in a variety of ways. previously sheep producers relied heavily on anti-parasitic drugs to control gastro-intestinal parasites of the flocks. but due to misuse of these drugs the parasites become resistant to drugs. thus cr ...201627413305
sero-prevalence of haemonchus contortus infection in sheep by indirect-elisa using somatic antigen.the present work was carried out to study the sero-prevalence of haemonchus contortus infection in sheep by indirect-enzyme linked immuno sorbent assay (indirect-elisa) using somatic antigen. out of 100 abomasums screened, 57 found positive for h. contortus adult worms. a total of 250 serum samples which includes, 100 serum samples from local abattoir in and around shimoga region from the animals from which the abomasums were collected and 150 serum samples from migratory sheep were used to dete ...201627413322
epizootological study of small ruminant gastrointestinal strongyles in gamo-gofa zone, southern ethiopia.the study was conducted with the objective to estimate the prevalence of gastrointestinal strongyles and identifying the prevailing strongyle species gamo-gofa zone. a total of 598 animals (241 sheep and 357 goats) and 45 animals (20 sheep and 25 goats) were examined coproscopically and by post mortem, respectively. the overall coproscopic prevalence of strongylosis in the study area was 51.4 %. strongyles were more prevalent in sheep than goats (95 % ci is 74.6-84.8 % and 58.6-68.6 % for sheep ...201627413323
anthelmintic efficacy of aqueous extract of zanthoxylum armatum dc. seeds against haemonchus contortus of small ruminants.haemonchus contortus infection is the major hurdle in growth and productivity in small ruminants especially in tropical countries. indiscriminate and long term use of currently available chemotherapeutic agents lead to development of resistance in microorganisms and residual problems in population. therefore, present study was undertaken to evaluate the anthelmintic efficacy of aqueous extract of zanthoxylum armatum dc. seeds against adult h. contortus worms of small ruminants. proximate analysi ...201627413333
evaluation of kumaon hill goats for resistance to natural infection with gastrointestinal nematodes.the present study deals with the investigation of different degrees of genetic resistance/resilience of uttarakhand hill goats to natural infection with gastrointestinal nematodes in order to introduce into breeding schemes. animals were naturally infected with haemonchus contortus, teladorsagia circumcincta, oesophagostomum spp. and trichostrongylus spp. faecal egg counts (fec) were carried out every month for a period of 1 year and blood samples were collected every third month for the determi ...201627413336
recent duplication and functional divergence in parasitic nematode levamisole-sensitive acetylcholine receptors.helminth parasites rely on fast-synaptic transmission in their neuromusculature to experience the outside world and respond to it. acetylcholine plays a pivotal role in this and its receptors are targeted by a wide variety of both natural and synthetic compounds used in human health and for the control of parasitic disease. the model, caenorhabditis elegans is characterized by a large number of acetylcholine receptor subunit genes, a feature shared across the nematodes. this dynamic family is ch ...201627415016
proteomic analysis of the excretory and secretory proteins of haemonchus contortus (hcesp) binding to goat pbmcs in vivo revealed stage-specific binding profiles.haemonchus contortus is a parasitic gastrointestinal nematode, and its excretory and secretory products (hcesps) interact extensively with the host cells. in this study, we report the interaction of proteins from hcesps at different developmental stages to goat peripheral blood mononuclear cells (pbmcs) in vivo using liquid chromatography-tandem mass spectrometry. a total of 407 hcesps that interacted with goat pbmcs at different time points were identified from a h. contortus protein database u ...201627467391
structural and functional characterization of a novel gene, hc-daf-22, from the strongylid nematode haemonchus contortus.the strongylid nematode haemonchus contortus is a parasite of major concern for modern livestock husbandry because hostile environmental conditions may induce diapause in the early fourth-stage larvae.201627472920
influence of sustained deworming pressure on the anthelmintic resistance status in strongyles of sheep under field conditions.anthelmintic resistance (ar) status in madras red sheep from selected field flocks of a government funded scheme, covered by regular, sustained anthelmintic treatment for more than 10 years was determined. parameters such as fecal egg count reduction test (fecrt), larval paralysis assay (lpa), and allele-specific-pcr (as-pcr) were used to test the efficacy of fenbendazole, tetramisole, and ivermectin at recommended doses, in two seasons. sheep belonging to non-beneficiary farmers were used as co ...201627509876
chemical composition and in vitro activity of calotropis procera (ait.) latex on haemonchus contortus.calotropis procera is among the species of medicinal plants that have traditionally been used for the treatment of parasites in small ruminants, stimulating the scientific validation of anthelmintic effects. this study aimed to investigate the chemical composition of ethyl acetate extract of calotropis procera latex (eaecpl), assess the in vitro effect against haemonchus contortus and the structural changes caused in the adult worm. the latex was collected, lyophilized and subjected to washing w ...201627514877
f200y polymorphism of the β-tubulin isotype 1 gene in haemonchus contortus and sheep flock management practices related to anthelmintic resistance in eastern amazon.the objective of the present study was to determine the frequency of the f200y polymorphism in the β-tubulin isotype 1 gene of haemonchus contortus from various sheep flocks in eastern amazon, and to identify management practices that may favor the emergence of resistance to anthelmintic drugs in the same area. in total, 305 specimens of h. contortus were collected from sheep at 12 farms located in the state of pará. an allele-specific pcr was performed to detect the f200y polymorphism, and ques ...201627514894
gastrointestinal nematode species diversity in soay sheep kept in a natural environment without active parasite control.molecular methods based on its2 sequence analysis were used to identify strongylid parasites and describe their diversity in a management intervention and anthelmintic drug treatment-free sheep flock. fourteen different nematode parasite species were identified in the flock and the results showed a greater level of nematode species diversity than is normally reported in managed farmed flocks, with the presence of parasites such as bunostomum trigonocephalum, ostertagia leptospicularis, spiculopt ...201627523929
synergism between ivermectin and the tyrosine kinase/p-glycoprotein inhibitor crizotinib against haemonchus contortus larvae in vitro.anthelmintic resistance is a major problem in parasitic nematodes of livestock worldwide. one means to counter resistance is to use synergists that specifically inhibit resistance mechanisms in order to restore the toxicity, and hence preserve the usefulness, of currently available anthelmintics. p-glycoproteins (p-gps) eliminate a wide variety of structurally unrelated xenobiotics from cells, and have been implicated in anthelmintic resistance. crizotinib is a tyrosine kinase inhibitor under de ...201627523939
efficacy of sainfoin (onobrychis viciifolia) pellets against multi resistant haemonchus contortus and interaction with oral ivermectin: implications for on-farm control.the worldwide spread of resistance to anthelmintic (ah) drugs in gastrointestinal nematodes (gins) imposes to explore alternative solutions. amongst those, the possible use of tannin-containing nutraceuticals appears as a relevant option to replace (or decrease the frequency of) chemical-based treatments. our objectives were to test the ah efficacy of sainfoin pellets against a multiresistant strain of haemonchus contortus in experimentally infected lambs and to examine possible interaction betw ...201627523948
screening of the 'pathogen box' identifies an approved pesticide with major anthelmintic activity against the barber's pole worm.there is a substantial need to develop new medicines against parasitic diseases via public-private partnerships. based on high throughput phenotypic screens of largely protozoal pathogens and bacteria, the medicines for malaria venture (mmv) has recently assembled an open-access 'pathogen box' containing 400 well-curated chemical compounds. in the present study, we tested these compounds for activity against parasitic stages of the nematode haemonchus contortus (barber's pole worm). in an optimi ...201627524698
anthelmintic activity of acetone extracts from south african plants used on egg hatching of <i>haemonchus contortus</i>.the nematode, haemonchus contortus, is responsible for major economic losses in the livestock industry. the management of parasites such as h. contortus has been through the use of synthetic parasiticides. this has resulted in the presence of residues in meat and milk, which affects food safety. the development of resistance to available anthelmintics coupled with their high cost has further complicated matters. this has led to the investigation of alternative methods to manage nematodes, includ ...201627543148
larvicidal activity of bacillus thuringiensis var. israelensis cry11aa toxin against haemonchus contortus.effective control of gastrointestinal parasites is necessary in sheep production. the development of anthelmintics resistance is causing the available chemically based anthelmintics to become less effective. biological control strategies present an alternative to this problem. in the current study, we tested the larvicidal effects of bacillus thuringiensis var. israelensis cry11aa toxin against haemonchus contortus larvae. bacterial suspensions [2 × 108 colony-forming units (cfu) g-1 of the fece ...201627573677
a field survey on the status of gastrointestinal helminth parasites in hangul (cervus elaphus hanglu) in dachigam national park of kashmir.one year crossectional survey was carried out to determine and describe the prevalence and intensity of gastrointestinal parasite infections in hangul (cervus elaphus hanglu) in dachigam national park of kashmir through faecal examinations. out of 153 faecal samples examined, 82 (53.59 %) were found infected with git helminthes. in present study seven helminth species were found, including five nematode [haemonchus contortus (55.39 %), trichuris ovis (39.75 %), dictyocaulus viviparus (28.4.00 %) ...201627605778
sex dependent alterations in the protein characterization patterns of haemonchus contortus.the aim of the study was to highlight the sex dependent differences in the electrophoretic protein patterns of male and female haemonchus contortus worms sds based polyacrylamide gels of both male and female worms were run side by side for comparison. a total of 33 and 35 polypeptides were detected in polyacrylamide gels stained with coomassie brilliant blue r-250, respectively. besides many of the fundamental homologies in protein profile, some of the polypeptides specific to either sex were al ...201627605828
effect of the infection with the nematode <i>haemonchus contortus</i> (strongylida: trichostrongylidae) on the haematological, biochemical, clinical and reproductive traits in rams.this study aimed to investigate the effect of haemonchus contortus infection on rams' haematological, biochemical and clinical parameters and reproductive performances. a total number of 12 barbarine rams (control and infected) were included in the experiment. the infected group received 30 000 h. contortus third-stage larvae orally. each ram's ejaculate was immediately evaluated for volume, sperm cell concentration and mortality rate. at the end of the experiment (day 82 post-infection), which ...201627608504
benzimidazole resistance in the ovine haemonchus contortus from southern poland - coproscopical and molecular findings.anthelmintic resistance within nematodes has become a very common issue, however, the data about its occurrence in the gastrointestinal nematodes of sheep in poland are very limited. this study was carried out in order to evaluate the presence of benzimidazole resistance in highly pathogenic haemonchus contortus by means of parasitological and molecular techniques. the research represents the first polish attempt to confirm the presence of a mutation at codon 200 of the β-tubulin isotype 1 gene ...201727614477
haemonchus contortus: the then and now, and where to from here?haemonchus contortus (barber's pole worm or "bpw") is the nematode "nemesis" of small ruminant production systems in tropical and subtropical regions of the world. its reputation derives from a combination of high fecundity and a short generational interval that provides an enviable developmental plasticity for adaptation or resistance to control measures. this review critically examines the historical and current literature on the host-parasite-environment interaction for h. contortus, particul ...201627620133
metabolic profiling and in vitro assessment of anthelmintic fractions of picria fel-terrae lour.anthelmintic resistance is widespread in gastrointestinal nematode populations, such that there is a consistent need to search for new anthelmintics. however, the cost of screening for new compounds is high and has a very low success rate. using the knowledge of traditional healers from borneo rainforests (sarawak, malaysia), we have previously shown that some traditional medicinal plants are a rich source of potential new anthelmintic drug candidates. in this study, picria fel-terrae lour. plan ...201627639945
melaleuca alternifolia anthelmintic activity in gerbils experimentally infected by haemonchus contortus.gastrointestinal parasites are one of the biggest health problems faced in sheep, mainly due to their pathogenicity and resistance to drugs used to control these parasites. thus, the following study aimed to assess the anthelmintic efficacy of melaleuca alternifolia against haemonchus contortus in gerbils (meriones unguiculatus) experimentally infected. three treatments were tested: m. alternifolia essential oil, popularly known as tea tree oil (tto), a solid lipid nanocarrier made with essentia ...201627646626
increased expression of atp binding cassette transporter genes following exposure of haemonchus contortus larvae to a high concentration of monepantel in vitro.there is some evidence that atp binding cassette (abc) transporters play a role in resistance to anthelmintics, particularly against macrocyclic lactones. some anthelmintics, including ivermectin (ivm), have been shown to induce transcription of multiple abc transporters in nematodes; however, the effects of monepantel (mpl) on transcription of these transporter genes has not been studied.201627682865
first report of the in vitro nematicidal effects of camel milk.antipathogenic properties of camel milk have been investigated to substitute for drugs hence overcome drug resistance. the main objective of this present study was to investigate the anthelmintic activity of camel milk in relationship to its chemical composition. in vitro anthelmintic effects of camel milk against haemonchus contortus from sheep were ascertained by egg hatching and worm motility inhibitions in comparison to milks from cow, ewe and goat as well as a reference drug albendazole. ch ...201627692318
thymus vulgaris l. essential oil and its main component thymol: anthelmintic effects against haemonchus contortus from sheep.haemonchus contortus is an important gastrointestinal parasite on sheep farms in tropical regions. the resistance of the parasite against most anthelmintic drugs represents a great economic problem to sheep farming and is a major challenge that needs to be overcome. the searches for new anthelmintic agents that act on different stages of the parasite's life cycle are necessary for the development of new therapeutic options. the aim of this study was to evaluate the in vitro and in vivo anthelmin ...201627692335
experimental infection of calves with haemonchus placei or haemonchus contortus: assessment of clinical, hematological and biochemical parameters and histopathological characteristics of abomasums.the present study had the primary objective of evaluating clinical, hematological and biochemical parameters, as well as observing anatomical and histopathological characteristics of abomasums, from calves prime-infected with haemonchus contortus or h. placei. ten male holstein newborns were subdivided in three groups (gi placebo; gii infected with h. contortus; giii inoculated with h. placei). eye mucosa staining was evaluated. hematological and biochemical tests were performed on animals. the ...201627693223
organometallic derivatization of the nematocidal drug monepantel leads to promising antiparasitic drug candidates.the discovery of novel drugs against animal parasites is in high demand due to drug-resistance problems encountered around the world. herein, the synthesis and characterization of 27 organic and organometallic derivatives of the recently launched nematocidal drug monepantel (zolvix(®) ) are described. the compounds were isolated as racemates and were characterized by (1) h, (13) c, and (19) f nmr spectroscopy, mass spectrometry, and ir spectroscopy, and their purity was verified by microanalysis ...201627706843
assessment of the nematocidal activity of metallocenyl analogues of monepantel.in this study, we present the design, synthesis, characterization and biological evaluation of structurally new ferrocenyl and ruthenocenyl derivatives of the organic anthelmintic monepantel (zolvix(®)). all seven metallocenyl derivatives prepared (4a/b, 5a/b, 6a/b and 7) were isolated as racemates and characterized by (1)h, (13)c and (19)f nmr spectroscopies, mass spectrometry, ir spectroscopy and elemental microanalysis. the molecular structures of four compounds (4a/b, 6a and 7) were further ...201627748782
recombinant protein of haemonchus contortus 14-3-3 isoform 2 (rhcftt-2) decreased the production of il-4 and suppressed the proliferation of goat pbmcs in vitro.14-3-3 proteins have been found to be an excreted/secreted antigen and assumed to be released into the host-parasite interface and described in several unicellular and multicellular parasites. however, little is known about the immunomodulatory effects of h. controtus 14-3-3 protein on host cell. in present study, 14-3-3 isoform 2 gene, designated as hcftt-2, was amplified by reverse transcription-polymerase chain reaction (rt-pcr) from the adult h. contortus cdna and cloned into expression plas ...201627751769
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