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phenotypic and genotypic characterisation of benzimidazole susceptible and resistant isolates of haemonchus contortus.the study was designed to compare the in vitro egg hatch test (eht) and molecular allele-specific polymerase chain reaction pcr (as-pcr) methods as tools for detection of benzimidazole resistance in haemonchus contortus, a nematode parasite of small ruminants. comparisons were made during the course of an experimental infection and changes in eht and as-pcr were monitored to measure the correlation between in vitro and molecular tests. both methods were carried out according to world association ...201020684865
comparison of parasitological and productive traits of criollo lambs native to the central mexican plateau and suffolk lambs experimentally infected with haemonchus contortus.the study compares the parasitological and productive traits of criollo lambs native to the central mexican plateau (cncmp) and suffolk (su) lambs experimentally infected with haemonchus contortus. cncmp lambs (n=20) and su lambs (n=15) were infected with l3 of h. contortus while five lambs of each genotype were kept as controls. fecal egg count (fec), packed cell volume (pcv), blood eosinophil number (ben), ocular mucous membrane color (as measured by the famacha index), changes in body conditi ...201020801736
intra-species variability in its-1 sequences of haemonchus contortus isolated from goats in west bengal, india.this study evaluated the existence of different genotypes of haemonchus contortus prevailing among goats in west bengal, india. these parasites were isolated from the abomasum of goat intestine and the molecular characterization was performed by comparing variation of nucleotide sequences of the internal transcribed spacer 1 (its-1) gene region. single-strand conformation polymorphism (sscp) analysis of its-1 amplified product showed the presence of three distinct conformations both in male and ...201020804642
effects of age and immune suppression of sheep on fecundity, hatching and larval feeding of different strains of haemonchus contortus.the effects of host age and immune suppression on abomasal parasitic infection in sheep were investigated following single experimental oral infections with mhco3 (ise), mhco4 (wrs) and mhco10 (cavr) strains of haemonchus contortus in naïve 5-month-old crossbred lambs (n=1 per group) and 15-month-old greyface sheep treated with methyl prednisolone acetate (n=2 per group) or without corticosteroid treatment (n=2 per group). adult female h. contortus in 5-month-old lambs (n=1 per group) shed on av ...201020822936
phylogenomics of ligand-gated ion channels predicts monepantel effect.the recently launched veterinary anthelmintic drench for sheep (novartis animal health inc., switzerland) containing the nematocide monepantel represents a new class of anthelmintics: the amino-acetonitrile derivatives (aads), much needed in view of widespread resistance to the classical drugs. recently, it was shown that the acr-23 protein in caenorhabditis elegans and a homologous protein, mptl-1 in haemonchus contortus, are potential targets for aad action. both proteins belong to the deg-3 s ...201020838602
a suite of genes expressed during transition to parasitic lifestyle in the trichostrongylid nematode haemonchus contortus encode potentially secreted proteins conserved in teladorsagia circumcincta.the control of gastro-intestinal nematodes remains largely based on anthelminthic treatments, however spreading of anthelmintic resistance has reduced their efficacy. the genes involved in the transition to parasitic lifestyle could constitute targets of interest to develop alternative control strategies. in the trichostrongylid nematode haemonchus contortus, we have used a ssh (suppressive subtractive hybridization) based approach to generate two distinct subtracted cdna libraries specifically ...201020843605
standardization of the larval migration inhibition test for the detection of resistance to ivermectin in gastro intestinal nematodes of ruminants.resistance to anthelmintics is an increasing problem in sheep, goat and cattle industries worldwide. for parasite management on farms reliable methods for the detection of resistance are required and it is important that tests give comparable, reproducible and reliable results in different laboratories. the ability of the larval migration inhibition test (lmit), to detect ivermectin resistance in cattle and sheep nematodes has been evaluated through ring testing in up to six different laboratori ...201020850930
localisation of serotonin and dopamine in haemonchus contortus.serotonin and dopamine play important roles in the biology of nematodes where they exert their effect on feeding, locomotion and reproductive behavior. haemonchus contortus, a parasitic nematode which infects small ruminants, is responsible for considerable economic losses in agriculture. in the current study we have mapped the localisation of these two neurotransmitters in this parasite using immuno-staining. serotonin localised in amphidial and pharyngeal neurons in both adult female and male ...201020887725
multiple resistance to anthelmintics by haemonchus contortus and trichostrongylus colubriformis in sheep in brazil.the objective of this study was to determine the level of resistance of haemonchus contortus and trichostrongylus colubriformis in sheep to levamisole, albendazole, ivermectin, moxidectin, closantel and trichlorfon. the parasites were isolated from sheep naturally infected by gastrointestinal nematodes and were then kept in monospecifically-infected lambs for production of infective larvae (l3) of both species. forty-two lambs, at three months of age, were simultaneously artificially infected wi ...201020887800
seasonal prevalence of gastrointestinal nematode parasites of sheep in northern region of nile delta, egypt.over 1 year, from january to december 1999, a total of 173 slaughtered sheep at al-mahala abattoir were examined for presence of nematode parasites. eighteen sheep (10.4%) were infected with eight different species of nematodes. the prevalence rates of detected nematode parasites were; haemonchus contortus (3.5%), haemonchus placei (1.7%), trichuris ovis (5.8%), parabronema skrjabini (2.9%), ostertagia trifurcata (1.2%), chabertia ovina (0.6%) and strongyloides papillosus (0.6%), and graphidiops ...201020922430
effects of artemisinin and artemisia extracts on haemonchus contortus in gerbils (meriones unguiculatus).haemonchus contortus is a blood-sucking abomasal parasite of small ruminants that is responsible for major losses to producers worldwide. resistance of this nematode to commercial anthelmintics has produced a demand for alternative control methods. plants in the genus artemisia have traditionally been used as anthelmintics and whole plants and plant extracts have demonstrated activity against gastrointestinal nematodes in several studies. in addition, artemisia annua is the sole commercial sourc ...201020943323
efficacy of anthelmintic properties of medicinal plant extracts against haemonchus contortus.the development of anthelmintic resistance has made the search for alternatives to control gastrointestinal nematodes of small ruminants imperative. among these alternatives are several medicinal plants traditionally used as anthelmintics. this present work evaluated the efficacy of ethyl acetate, acetone, and methanol dried leaf and seed extracts of five medicinal plants were tested in vitro ovicidal and larvicidal activities on haemonchus contortus. the in vitro assay was based on egg hatch as ...201020980034
antibodies from sheep immunized against haemonchus contortus with h-gal-gp inhibit the haemoglobinase activity of this protease complex.highly protective intestinal cell membrane antigens have been prepared from haemonchus contortus, an important blood feeding nematode which parasitizes sheep and goats. one such antigen, h-gal-gp, is a glycoprotein complex containing predominantly digestive proteases. this study showed that h-gal-gp readily digested ovine haemoglobin and albumin, the two most abundant proteins in the parasite's blood meal. it was found that adding protective antibodies from h-gal-gp immunized sheep to the h-gal- ...201021039613
arginine metabolism in the sheep abomasal nematode parasites haemonchus contortus and teladorsagia circumcincta.the ornithine urea cycle, polyamine synthesis, nitric oxide synthesis and metabolism of arginine to putrescine have been investigated in l3 and adult haemonchus contortus and teladorsagia circumcincta. neither parasite had a detectable arginine deiminase/dihydrolase pathway nor a functional ornithine urea cycle. nitric oxide synthase was present in central and peripheral nerves, but was not detected in whole parasite homogenates. both arginase (e.c. 3.5.3.1) and agmatinase (e.c. 3.5.3.11) activi ...201021055403
systems biology of ovine intestinal parasite resistance: disease gene modules and biomarkers.this study reports on the molecular systems biology of gastrointestinal nematode (gin) infection and potential biomarkers for gin resistance in sheep. microarray gene expression data were obtained for 3 different tissues at 4 time points from sheep artificially challenged with two types of nematodes, haemonchus contortus (hc) and trichostrongylus colubriformis (tc). we employed an integrated systems biology approach, integrating 3 main methods: standard differential gene expression analyses, wei ...201021072409
the activity and hydrogen peroxide sensitivity of the peroxiredoxins from the parasitic nematode haemonchus contortus.the requirement of aerobic organisms to control damage caused by reactive oxygen species has led to the evolution of the antioxidant systems. peroxiredoxins are a large family of peroxidases which detoxify hydrogen peroxide at the expense of thiols. the parasitic nematode haemonchus contortus contains two peroxiredoxins, hcprx1 a mitochondrial protein and hcprx2 a cytoplasmic protein. although both peroxiredoxins contain the conserved eukaryotic motifs 'gglg' and 'yf', identified as critical for ...201021075149
anthelminthic activity of acetone extract and fractions of vernonia amygdalina against haemonchus contortus eggs and larvae.the current control of parasitic nematodes in small ruminants relies on the use of chemical anthelminthics, but the development of resistance and the problem of drug residues require research into alternatives. acetone extract and solvent-solvent fractions of vernonia amygdalina del. (compositae) were evaluated in vitro for potential anti-parasitic effects against the eggs and larvae of haemonchus contortus. significant effects were obtained with the extract and fractions but differences were ob ...201021088894
a novel high throughput assay for anthelmintic drug screening and resistance diagnosis by real-time monitoring of parasite motility.helminth parasites cause untold morbidity and mortality to billions of people and livestock. anthelmintic drugs are available but resistance is a problem in livestock parasites, and is a looming threat for human helminths. testing the efficacy of available anthelmintic drugs and development of new drugs is hindered by the lack of objective high-throughput screening methods. currently, drug effect is assessed by observing motility or development of parasites using laborious, subjective, low-throu ...201021103363
a modified in vitro larvae migration inhibition assay using rumen fluid to evaluate haemonchus contortus viability.anthelmintic effects of plant secondary compounds may be occurring in the rumen, but in vitro larvae migration inhibition (lmi) methods using rumen fluid and forage material have not been widely used. forage material added to an in vitro system can affect rumen ph, ammonia n, and volatile fatty acids, which may affect larvae viability (lv). validating a lmi assay using rumen fluid and a known anthelmintic drug (ivermectin) and a known anthelmintic plant extract (quebracho tannins; qt) is importa ...201021109354
in vivo anthelmintic activity of an aqueous extract from sisal waste (agave sisalana perr.) against gastrointestinal nematodes in goats.the resistance of gastrointestinal nematodes (gins) of small ruminants to anthelmintics has required the investigation of new alternatives. the aim of the present study was to evaluate the in vivo anthelmintic activity of an aqueous extract from sisal waste (agave sisalana) (aesw) against gins in goats and to observe the animals for toxic effects. thirty animals that were naturally infected with gins were distributed into three groups: group i, was treated with daily doses of aesw (1.7 g/kg) for ...201021156340
albendazole failure to control resistant nematodes in lambs: lack of effect of fasting-induced improvement on drug absorption.enhanced plasma availability of albendazole sulphoxide (abzso), the active metabolite of albendazole (abz), has been described in feed-restricted sheep. the aim of the present work was to determine if the absorption-related pharmacokinetic changes derived from fasting animals prior to drug treatment would modify the clinical efficacy of abz against resistant gastrointestinal nematodes in lambs. forty corriedale lambs, naturally infected with resistant gastrointestinal nematodes, were divided int ...201021158637
anthelmintic activity of botanical extracts against sheep gastrointestinal nematodes, haemonchus contortus.the source of chemical anthelmintics (levamisole, flubendazole, and thiabendazole) had limited the success of gastrointestinal nematodiasis control in sheep and goats and thus awakened interest in the study of medicinal plant extracts as alternative sources of anthelmintics. the egg hatching and larvicidal effect of indigenous plant extracts were investigated against the sheep parasite, haemonchus contortus. the purpose of the present study was to assess the efficacy of leaf, bark, and seed ethy ...201021161270
differences in efficacy of monepantel, derquantel and abamectin against multi-resistant nematodes of sheep.drug resistance has become a global phenomenon in gastrointestinal nematodes of sheep, particularly resistance to macrocyclic lactones. new anthelmintics are urgently needed for both the control of infections with multi-resistant nematodes in areas where classical anthelmintics are no longer effective, and the prevention of the spread of resistance in areas where the problem is not as severe. recently, two new active ingredients became commercially available for the treatment of nematode infecti ...201021161271
persistence of the efficacy of copper oxide wire particles against haemonchus contortus in sheep.the aim was to determine the persistent efficacy of copper oxide wire particles (cowp) against haemonchus contortus in sheep, using the harmonization guidelines protocol. thirty-six male lambs (2 months old) reared free of gastrointestinal nematodes were used (average body weight of 10.8±3.8kg). before and for the duration of the study, lambs were kept in raised cages with slatted floors and were offered ad libitum a complete mixed diet. animals were divided into six groups (n=6): one non-treate ...201021163579
covariate selection in multivariate spatial analysis of ovine parasitic infection.gastrointestinal (gi) strongyle and fluke infections remain one of the main constraints on health and productivity in sheep dairy production. a cross-sectional survey was conducted in 2004-2005 on ovine farms in the campania region of southern italy in order to evaluate the prevalence of haemonchus contortus, fasciola hepatica, dicrocoelium dendriticum and calicophoron daubneyi from among other parasitic infections. in the present work, we focused on the role of the ecological characteristics of ...201021167615
the kinetics of local cytokine and galectin expression after challenge infection with the gastrointestinal nematode, haemonchus contortus.gastrointestinal nematode parasites undergo several developmental stages within their mammalian host, each presenting different antigenic challenges to the immune system. to examine the expression of different immune mediators over time, biopsy samples were collected from the cannulated abomasum (true stomach) of immune sheep at several times after a challenge infection with haemonchus contortus l3s. il-5 and il-13 mrna expression levels were significantly increased above saline-challenged contr ...201021172352
cloning, expression and characterization of nad+-dependent glyceraldehyde-3-phosphate dehydrogenase of adult haemonchus contortus†glyceraldehyde-3-phosphate dehydrogenase (gapdh) regulates a wide range of biological processes, including pathogen evasion. in the present research, the gapdh gene of haemonchus contortus (hcgapdh) was cloned and characterized. specific primers for the rapid amplification of cdna ends (race) were designed based on the expressed sequence tag (est, aw670737) to amplify the 3′ and 5′ ends of hcgapdh. the full length of cdna from this gene was obtained by overlapping the sequences of 3′ and 5 ...201021205411
differences in immune parameters are associated with resistance to haemonchus contortus in caribbean hair sheep.caribbean hair sheep are more resistant to gastrointestinal nematodes than conventional wool breeds, but mechanisms that confer resistance are not fully understood. this study compared immune effector cell populations and antibody concentrations in 12 hair and 12 wool lambs infected with the abomasal parasite haemonchus contortus and sacrificed at 3 or 27 days post-infection (p.i.) and 14 uninfected animals of each breed. faecal egg counts were over 2.5-fold higher (p = 0.12) and packed cell vol ...201020591119
effect of a tropical tannin-rich plant lysiloma latisiliquum on adult populations of haemonchus contortus in sheep.bioactive plants with anthelmintic (ah) properties represent a promising alternative solution to chemical treatments. the ah effect of several mexican tannin-rich (tr) plants has been screened in vitro. the in vivo ah effect of one tr legume, lysiloma latisiliquum (tzalam) on nematode larval establishment was confirmed. the present trial aimed at evaluating the direct and indirect effects of l. latisiliquum fodder consumption on adult haemonchus contortus. twenty-two parasite-naïve hair sheep la ...201020605336
interference with p-glycoprotein improves ivermectin activity against adult resistant nematodes in sheep.the in vivo co-administration of ivermectin (ivm) with p-glycoprotein (p-gp) modulator agents has been shown to enhance its systemic availability. however, there is no sufficient evidence on the impact that this type of drug-drug interaction may have on the in vivo efficacy against resistant nematodes in ruminant species. the current work reports on the effects of loperamide (lpm), a p-gp modulating agent, on both ivm kinetic behaviour and anthelmintic activity in infected lambs. eighteen (18) l ...201020605686
effect of selenium and vitamin e on oxidative stress in lambs experimentally infected with haemonchus contortus.the objective of this study was to evaluate oxidative stress in lambs experimentally infected with haemonchus contortus and supplemented with selenium and vitamin e. twenty male corriedale lambs were divided into four experimental groups with five animals each: g1 consisted of animals infected and supplemented with 0.2 mg/kg of live weight (lw) sodium selenite by intramuscular injection (im); g2 consisted of animals infected with larvae and supplemented with 0.2 mg/kg lw sodium selenite im and 2 ...201020607397
anthelmintic effect of eucalyptus staigeriana essential oil against goat gastrointestinal nematodes.the aim of this study was to evaluate the anthelmintic efficacy of eucalyptus staigeriana essential oil (eseo). the in vitro effects of eseo were determined through the egg hatching test and the inhibition of larval development of haemonchus contortus. the oil was subjected to acute and subacute toxicity rodents. the in vivo effects were determined through fecal egg count reduction test in goats. 1.35 and 5.4 mgml(-1) eseo inhibited 99.27 and 99.20% h. contortus egg hatching and larval developme ...201020609526
immunization against lamb haemonchosis with a recombinant somatic antigen of haemonchus contortus (rhcp26/23).haemonchosis, caused by the abomasal nematode haemonchus contortus, is a common parasitic disease of sheep. our previous results showed that a soluble fraction from adult stages of the nematode (p26/23) induced partial protection against challenge. recombinant dna technology was applied to obtain a synthetic protein (rhcp26/23). immunological assays (elisa, western blotting, and immunolocalization), using sera from lambs immunized with p26/23, confirmed the identity of the recombinant protein an ...201020631899
drug target prediction and prioritization: using orthology to predict essentiality in parasite genomes.new drug targets are urgently needed for parasites of socio-economic importance. genes that are essential for parasite survival are highly desirable targets, but information on these genes is lacking, as gene knockouts or knockdowns are difficult to perform in many species of parasites. we examined the applicability of large-scale essentiality information from four model eukaryotes, caenorhabditis elegans, drosophila melanogaster, mus musculus and saccharomyces cerevisiae, to discover essential ...201020361874
a vacuolar-type proton (h+) translocating atpase alpha subunit encoded by the hc-vha-6 gene of haemonchus contortus.in the present study, a full-length cdna (designated hc-vha-6) inferred to encode an alpha subunit of a vacuolar-type proton translocating adenosine triphosphatase (v-atpase) was isolated from the parasitic nematode haemonchus contortus, and characterized. the transcript for hc-vha-6 was detected in all developmental stages and both sexes of h. contortus. elements, including two tata box (tataa), two inverted caat box (attgg), five e box (canntg) and six gata as well as five inverse gata (ttatc) ...201020362051
biological characterization and pathogenicity of three haemonchus contortus isolates in primary infections in lambs.the biological characterization and differential pathogenicity of three isolates of haemonchus contortus, one autochthonous (aran 99) and two allochthonous (moredun research institute, mri, and merck sharp and dohme, msd) were studied by primary experimental infection of manchego lambs. thus, six female lambs (5.5 months old) were infected with 12,000 l3 larvae of each helminth isolate. parasitological (pre-patent period, parasite egg shedding dynamics), biopathological (packed cell volume (pcv) ...201020363563
resistance and resilience of west african dwarf goats of the nigerian savanna zone exposed to experimental escalating primary and challenge infections with haemonchus contortus.we assessed the resilience and resistance to infection with haemonchus contortus of savanna west african dwarf (wad) goats from northern nigeria. adult male goats (n=32) were given an escalating immunizing infection, comprising 5 weekly infections with increasing numbers of larvae. on day (d) 56 they were segregated into low (lfec) and high (hfec) faecal egg count phenotypes, and within each phenotype 7 goats were treated with anthelmintic and seven received no treatment. four goats were culled ...201020378252
detection of quantitative trait loci for internal parasite resistance in sheep. i. linkage analysis in a romney x merino sheep backcross population.this study aimed to identify putative quantitative trait loci (qtl) that significantly affect internal parasite resistance in a backcross sheep population. a romney x merino backcross (to merino) flock was challenged in 3 separate infections with trichostrongylus colubriformis (primary and secondary) and haemonchus contortus (tertiary). haematological parameters were measured and faecal worm egg counts (fwec) were established to estimate parasite burden. qtl mapping was conducted for fwec and fo ...201020388239
effect of route of administration on the efficacy and pharmacokinetics of an experimental formulation of the amino-acetonitrile derivative monepantel in sheep.the effect of the route of administration (oral, intraruminal and intra-abomasal) on the efficacy and pharmacokinetics of the new anthelmintic monepantel in sheep was investigated. the target nematodes were fourth-stage haemonchus contortus, teladorsagia circumcincta, trichostrongylus colubriformis and cooperia curticei. a clear difference in efficacy was identified between the routes of administration, although the difference did not consistently reach statistical significance; oral treatment w ...201020400740
[red stomach worm]. 201020419878
differences in transcription between free-living and co2-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 gastric nematode is enclosed in a cuticle (sheath) and, once ingested with herbage by the host, undergoes an exsheathment process that marks the transition from the free-living (l3) to the parasitic (xl3) stage. this study explored changes in gene transcription associated with this transition and predicted, based on compa ...201020420710
the gene structure and promoter region of the vaccine target aminopeptidase h11 from the blood-sucking nematode parasite of ruminants, haemonchus contortus.aminopeptidase h11, an integral membrane glycoprotein present only in the gut of haemonchus contortus, could provide substantial protection as shown by 90% reduction in fecal egg counts, while its recombinant version expressed in e. coli induced little. to investigate the characteristics further, we amplified mrna of h11 gene via reverse transcriptase polymerase chain reaction, followed by isolation of its 1,517-bp 5'-flanking region and determination of its genomic organization. the h11 gene co ...201020437190
flubendazole metabolism and biotransformation enzymes activities in healthy sheep and sheep with haemonchosis.the aim of this project was to study the influence of haemonchosis, a common parasitic infection of small ruminants caused by haemonchus contortus, on the activity of biotransformation enzymes and on in vitro flubendazole (flu) biotransformation in liver and small intestine of lambs (ovis aries). twelve lambs were divided into three groups: non-infected animals, animals orally infected with larvae of h. contortus ise strain for 7 weeks and for 11 weeks. at the end of the experiment, hepatic and ...201020444026
efficacy of an orange oil emulsion as an anthelmintic against haemonchus contortus in gerbils (meriones unguiculatus) and in sheep.haemonchus contortus is a blood-sucking abomasal parasite responsible for major losses to small ruminant producers worldwide. the recent increase in populations of anthelmintic resistant parasites has produced a demand for alternative control methods. an orange oil emulsion that has shown activity against plant parasitic nematodes and h. contortus in vitro was assessed for activity against h. contortus in a gerbil model and in the natural ovine host. in gerbil experiments, animals were infected ...201020452126
characterization of a novel tyramine-gated chloride channel from haemonchus contortus.tyramine (ta), a trace amine, is becoming accepted as a main stream neurotransmitter in invertebrates. recent evidence indicates that part of the function of ta in nematodes involves a novel receptor (cel-lgc-55) from the ligand-gated chloride channel class of ionotropic receptors. however, the role of ta or its receptors in the biology of nematode parasites is limited. haemonchus contortus is a deadly parasitic worm which causes significant economic burden in the production of small ruminants i ...201020471431
substrate specificity of the mitochondrial thioredoxin reductase of the parasitic nematode haemonchus contortus.thioredoxin reductase (trxr) is an evolutionary diverse enzyme. in higher eukaryotes, trxr contains a selenocysteine in the active site which confers high activity and a broad substrate range. the parasitic nematode haemonchus contortus contains two trxrs, a cytoplasmic enzyme hctrxr1 with a selenocysteine in the active site (gly-cys-secys-gly), similar to the mammalian trxr, and a mitochondrial enzyme hctrxr2 with a gly-cyc-cys-gly active site which is unique to nematodes. both enzymes were clo ...201020495929
attempts to immunize sheep against haemonchus contortus using a cocktail of recombinant proteases derived from the protective antigen, h-gal-gp.the objective of this study was to determine whether an antigen cocktail containing recombinantly expressed versions of most of the protective proteases of h-gal-gp, a known protective antigen from haemonchus contortus, would confer any protection to lambs in a vaccine-challenge trial. haemonchus contortus metalloendopeptidases, mep1, mep3 and mep4, were expressed as soluble recombinant proteins in insect cells, but attempts to express the h. contortus aspartyl proteases, pep1 and pep2, by the s ...201020500672
genetic diversity of levamisole receptor subunits in parasitic nematode species and abbreviated transcripts associated with resistance.the molecular mechanisms of levamisole (lev) activity and expression of resistance remain largely unknown in parasitic nematodes. in contrast, genetic screens for mutants that survive exposure to lev in the free-living nematode caenorhabditis elegans have led to the identification of five genes (unc-38, unc-63, unc-29, lev-1 and lev-8) that encode a lev-sensitive acetylcholine receptor (l-achr). loss of these genes leads to lev resistance. in this study, orthologues of these genes were identifie ...201020531256
gastrointestinal helminthiasis: prevalence and associated determinants in domestic ruminants of district toba tek singh, punjab, pakistan.the objective of the present study was to determine the prevalence and associated determinants (e.g., sex, age, on-farm management and husbandry) of gastrointestinal (gi) helminths in the domestic animals of district toba tek singh, punjab, pakistan. for this purpose, 1,140 cattle, 1,140 buffaloes, 660 goats, 840 sheep, and 156 camels were randomly selected and their fecal samples were screened every other week for a year using a modified floatation technique. the samples positive for strongyle- ...201020532913
biochemical characterization of two purified proteins of the ib-16 bacillus thuringiensis strains and their toxicity against the sheep nematode haemonchus contortus in vitro.the aim of this study was to characterize the biochemical composition of two main ib-16 bacillus thuringiensis proteins and to determine their toxicity on the blood-feeder nematode, haemonchus contortus. the soluble toxin of ib-16 strain of b. thuringiensis produces five main bands of proteins, the chemical composition of which might play an important role on the lethal activity. two bands of proteins around 25 and 70 kda were chosen and purified by hplc using a hydrogel column and sephadex-bead ...201020537121
neutrophil oxidative metabolism and haemogram of sheep experimentally infected with haemonchus contortus and supplemented with selenium and vitamin e.the objective of this study was to evaluate neutrophil oxidative metabolism and haemogram in sheep experimentally infected with haemonchus contortus and supplemented with selenium and vitamin e. twenty male corriedale sheep were utilised and distributed into four experimental groups each with five animals infected with larvae: g1--supplemented with sodium selenite, 0.2 mg/kg body weight (bw) given intramuscularly (im); g2--supplemented with sodium selenite and vitamin e, 0.2 mg/kg bw and 2000 iu ...201020546075
effect of feeding bioactive forages on infection and subsequent development of haemonchus contortus in lamb faeces.contrasting dried herbage diets were offered to lambs to evaluate their effects on haemonchus contortus infection and on subsequent development of larvae in faeces. artificially infected lambs (n=24, 4 months old) were allocated to one of four treatment groups (n=6) and fed on hay of lucerne (medicago sativa; lu), sulla (hedysarum coronarium; su), sainfoin (onobrychis viciifolia; sa) or wormwood (artemisia absinthium; wo) included as 20% in ground lucerne pellets. while voluntary intake was simi ...201020554118
drug resistance is affected by colocalization of p-glycoproteins in raft-like structures unexpected in eggshells of the nematode haemonchus contortus.in nematodes as in other eukaryotes, there is increasing evidence that drug resistance depends on both changes in the drug cellular targets and in nonspecific mechanisms, involving cellular detoxification by efflux pumps. in vertebrates, p-glycoproteins (pgp) are membrane efflux pumps responsible for the elimination of xenobiotic agents, especially drugs. we previously reported the presence of pgp pumps in eggshells and cuticles of the nematode haemonchus contortus. eggshells and cuticles are di ...201020555388
decrease in establishment of haemonchus contortus caused by inoculation of a taenia hydatigena larvae vesicular concentrate.the effect of taenia hydatigena larvae vesicular concentrate (thlvc) on the establishment of an experimental infection by haemonchus contortus was evaluated. the lambs that received thlvc showed a greater (p<0.05) average of blood eosinophils (be) than the lambs that did not receive thlvc. lambs that were only infected with h. contortus larvae showed a fecal egg count (fec) and an adult phase (ap) number greater (p<0.05) than lambs that received thlvc prior to infection. no effect was observed i ...201021216105
effect of feeding sericea lespedeza leaf meal in goats experimentally infected with haemonchus contortus.effect of sericea lespedeza [sl; lespedeza cuneata (dum-cours.) g. don.] leaf meal feeding was evaluated in two experiments in indoor reared goats with experimental infection of haemonchus contortus larvae. in the first experiment, ten 8-10 month old male spanish and alpine cross kids pair matched for body weight and age were fed sl or bermudagrass [bg; cynodon dactylon (l.) pers.] hay one week before infection and were infected with 5000 h. contortus l(3). the animals were maintained on the sam ...201021232867
contrasting genetic structures of two parasitic nematodes, determined on the basis of neutral microsatellite markers and selected anthelmintic resistance markers.for the first time, the neutral genetic relatedness of natural populations of trichostrongylid nematodes was investigated in relation to polymorphism of the beta-tubulin gene, which is selected for anthelminthic treatments. the aim of the study was to assess the contribution of several evolutionary processes: migration and genetic drift by neutral genetic markers and selection by anthelminthic treatments on the presence of resistance alleles at beta-tubulin. we studied two nematode species (tela ...200919900171
anthelminthic resistance of haemonchus contortus in small ruminants in switzerland and southern germany.two goat and two sheep flocks have been found to be suspicious of a clinically evident reduced anthelmintic efficacy, i.e. lacking improvement of gastrointestinal disorders, insufficient weight gain and continuing inappetence after anthelmintic treatments. in order to conduct an appropriate evaluation of the efficacy the following trials were performed: the faecal egg count reduction test on the studied goats of the two herds revealed a reduction of the egg-excretion after the eprinomectin-treat ...200919915817
[ovicidal and larvicidal activity in vitro of eucalyptus globulus essential oils on haemonchus contortus].the objective of this work was to evaluate ovicidal and larvicidal effects of eucalyptus globulus essential oil (egeo) on haemonchus contortus. the chemical composition determination of egeo was through gas chromatography and mass spectrometry. egg hatch test (eht) was performed in concentrations 21.75; 17.4; 8.7; 5.43 e 2.71 mg x ml(-1). in larval development test (ldt) were used the concentrations 43.5; 21.75; 10.87; 5.43 e 2.71 mg x ml(-1). each trial was conducted by negative control with tw ...200919772778
adjuvant effect of lps and killed propionibacterium acnes on the development of experimental gastrointestinal nematode infestation in sheep.gastrointestinal helminthic infection is an important worldwide sheep disease. the emergence of anthelminthic resistance has led to drives to seek new means of therapeutic control of helminthiasis in sheep. several data demonstrated the adjuvant effect of propionibacterium acnes on resistance to infection. herein, we evaluate the adjuvant effect of the commercial suspension containing lps and p. acnes on experimental helminthiasis. sheep received three doses of lps and p. acnes commercial suspen ...200919751472
eosinophils in haemonchus contortus-infected resistant and susceptible breeds of sheep: abomasal tissue recruitment and in vitro functional state.a comparative experimental study was performed between barbados black belly (resistant) and inra-401 (susceptible) breeds of sheep in which primary infection with haemonchus contortus was terminated on day 16. measurements of parasite burden, abomasal tissue eosinophilia, il-4, il-5 and il-13 mrna transcripts in abomasal mucosa, and in vitro larval killing abilities of blood eosinophils were performed. the results show that: (1) worm burden was significantly lower and blood eosinophilia higher i ...200919733438
is the famacha chart suitable for every breed? correlations between famacha scores and different traits of mucosa colour in naturally parasite infected sheep breeds.infections with gastrointestinal nematodes, in particular haemonchus contortus, are worldwide one of the most important factors causing high economic losses in sheep production. different methods for detecting infections with h. contortus have been described, such as, e.g. the famacha system, which categorises the colour of the conjunctivae from red to pale. when h. contortus is not the predominant parasite, the famacha chart might not be suitable to detect nematode infections, because of the la ...200919699035
resistance of santa ines and crossbred ewes to naturally acquired gastrointestinal nematode infections.this trial was carried out in piracicaba, são paulo state, brazil, to comparatively evaluate the degree of resistance to naturally acquired gastrointestinal nematode infections in sheep of the following genetic groups: purebred santa ines (si), si crossbred with dorper (do x si), ile de france (if x si), suffolk (su x si), and texel (te x si). fifteen ewes from each group were raised indoors until 12 months of age. at this age, they were moved to pasture that was naturally contaminated by nemato ...200919656629
parasitological and clinical responses of lambs experimentally infected with haemonchus contortus (l3) with and without ivermectin treatment.haemonchus contortus is one of the most important parasites that infects sheep and exerts its pathogenic effects by sucking blood, causing disturbances of organ-functions and thus inducing alterations in various normal physiological parameters. changes in live body weight, faecal egg count, kinetics of circulating eosinophils and pcv value were studied at weekly interval for a period of 84 days in 18 lambs of local breed after infection with a single dose of 5000 h. contortus (l(3)). in the two ...200919683874
bioseparation and activity of khaya senegalensis fractions against infective larvae of haemonchus contortus.the anthelmintic constituents of khaya senegalensis (deser.) a. juss (meliaceae) bark extract, previously demonstrated to show both in vitro and in vivo activity against gastrointestinal nematodes of sheep was investigated by chromatographic separation of the crude extract and bioassay of fractions. bioseparation of the crude ethanol (95%) extract was carried out by gradient vacuum liquid chromatographic analysis and thin layer chromatography fingerprinting of eluates. the activity of the fracti ...200919625127
the putative cyclooctadepsipeptide receptor depsiphilin of the canine hookworm ancylostoma caninum.the g-protein-coupled receptor hc110-r of haemonchus contortus and its orthologue in caenorhabditis elegans, the latrophilin-like protein 1 (lat-1), were shown to play a role in the mode of action of the new anthelmintic compound emodepside. c. elegans lat-1 knockout mutants showed a decreased paralysing effect of emodepside on the pharyngeal muscle. in the present study, the lat-1 orthologue in the canine hookworm ancylostoma caninum was identified and named depsiphilin. to obtain more informat ...200919575230
epidemiology and effects of gastrointestinal nematode infection on milk productions of dairy ewes.66 pampinta breed ewes were studied during milking to evaluate the infection and the effect of gastrointestinal nematode on milk production sheep system. naturally infected ewes on pasture were randomly allocated to two groups: tg, suppressively treated group every four weeks with levamisole and ug, untreated group. faecal nematode egg counts and larval differentiation were conducted monthly. successive groups of worm free tracer lambs were grazed with ewes and then slaughtered for worm counts. ...200919585893
effect of fasting sheep for a short period on the efficacy and safety of monepantel.eighteen, six- to seven-month-old lambs were infected experimentally with larvae of haemonchus contortus, teladorsagia circumcincta, trichostrongylus axei, trichostrongylus colubriformis, cooperia curticei and nematodirus spathiger, and allocated to three equal groups. the infections were timed to ensure that fourth-stage larvae were present when groups 1 and 2 were treated orally with monepantel. group 1 was not fed for 24 hours before the treatment, group 2 was fed two hours before the treatme ...200919596676
the complexity of the secreted npa and far lipid-binding protein families of haemonchus contortus revealed by an iterative proteomics-bioinformatics approach.two different classes of small nematode specific lipid-binding proteins, the nematode polyprotein allergens/antigens (npas) and the fatty acid- and retinol-binding (far) proteins, are secreted by helminth parasites. until now, there was no evidence of the expression or secretion of these two families of proteins in haemonchus contortus. in this study, we applied proteomic and bioinformatic tools in an iterative manner to reveal the expression and complexity of these proteins in the excretory/sec ...200919615410
in vitro selection of haemonchus contortus for benzimidazole resistance reveals a mutation at amino acid 198 of beta-tubulin.benzimidazoles were the first broad-spectrum anthelmintics and are still in use today against gastro-intestinal nematodes of ruminants such as haemonchus contortus. benzimidazoles block the polymerization of nematode microtubules. however, their efficacy is jeopardized by the spread of drug-resistant parasites that carry point mutations in beta-tubulin. here we use a novel in vitro selection-in vivo propagation protocol to breed drug-resistant h. contortus. after 8 generations of selection with ...200919616042
fast, automated measurement of nematode swimming (thrashing) without morphometry.the "thrashing assay", in which nematodes are placed in liquid and the frequency of lateral swimming ("thrashing") movements estimated, is a well-established method for measuring motility in the genetic model organism caenorhabditis elegans as well as in parasitic nematodes. it is used as an index of the effects of drugs, chemicals or mutations on motility and has proved useful in identifying mutants affecting behaviour. however, the method is laborious, subject to experimenter error, and theref ...200919619274
development and validation of real-time pcr methods for diagnosis of teladorsagia circumcincta and haemonchus contortus in sheep.parasitic gastroenteritis, a disease caused by parasitic nematodes, is of major concern to the sheep industry and threatens sustainability. traditional methods for diagnosis of the type and level of infection in a sheep flock require laborious laboratory extraction, culture and microscopic examination of eggs or larvae from faecal samples. advances in molecular technology offer the potential for more efficient and reliable methods. this study aimed to develop and test a real-time pcr method for ...200919836895
[sheep trichostrongylidosis in van province].this study was performed in the van municipality slaughterhouse from january to december 2001. abomasums and small intestines from a total of 104 sheep were transported to the parasitology laboratory of the veterinary faculty of yüzüncü yil university for parasitological examination. the abomasums and small intestines of the animals were opened with appropriate technique in the laboratory, and male nematodes were collected from the contents of the abomasums and small intestines using a sampling ...200919851969
further characterization of a cattle nematode population with demonstrated resistance to current anthelmintics.we previously documented the appearance of cattle nematode parasites resistant to avermectins, milbemycin, and a benzimidazole at the end of a grazing season in a backgrounding operation in the upper midwestern us. to further characterize the pattern of drug resistance, we extended the study to (1) monitor the animals over the course of the grazing season; (2) increase the number of animals slaughtered at the end of the season to minimize the effect of potential outlying observations; (3) increa ...200919897305
determination of genomic dna sequences for beta-tubulin isotype 1 from multiple species of cyathostomin and detection of resistance alleles in third-stage larvae from horses with naturally acquired infections.abstract : background : genetic resistance against benzimidazole (bz) anthelmintics is widespread in cyathostomins, the commonest group of intestinal parasitic nematodes of horses. studies of bz-resistant nematodes of sheep, particularly haemonchus contortus, have indicated that an anthelmintic resistance-conferring t/a polymorphism, encoding an f (phenylalanine) to y (tyrosine) substitution, in beta-tubulin isotype 1 is present at two loci, codons 167 and 200 (f167y, f200y). recent studies usin ...200919778467
the efficacy of monepantel, an amino-acetonitrile derivative, against gastrointestinal nematodes of sheep in three countries of southern latin america.the efficacy of the novel anthelmintic, monepantel (an amino-acetonitrile derivative), was investigated in sheep naturally infected with gastrointestinal nematodes in five studies in argentina, brazil, and uruguay. monepantel, administered at 2.5 mg/kg liveweight, was highly effective (>99.7%) against haemonchus contortus, teladorsagia (ostertagia) circumcincta, trichostrongylus axei, trichostrongylus colubriformis, cooperia curticei, cooperia mcmasteri, cooperia oncophora, cooperia pectinata, c ...200919789895
the effect of long-term feeding of fresh and ensiled cassava (manihot esculenta) foliage on gastrointestinal nematode infections in goats.the benefit of long-term feeding of fresh or ensiled cassava foliage on gastrointestinal parasite in goats was evaluated. eighteen male goats (15.15 +/- 2.83 kg and between 4-6 months) were randomly allocated into three treatments supplemented with 200 g of wheat bran head(-1) day(-1). all groups were fed ad-libitum on either grass (co), fresh cassava (caf) or ensiled cassava foliage (cas). at the beginning of the trial, each goat was inoculated with 3000 l3 containing approximately 50% haemonch ...200918516697
prevalence of helminths in water buffaloes in hunan province, china.the prevalence of helminths in the asian water buffaloes (bubalus bubalis) was investigated in hunan province, people's republic of china between april 2005 and october 2007. a total of 359 adult buffaloes slaughtered at local abattoirs in 12 representative geographical locations in hunan province were examined for the presence of helminths. the worms were examined, counted and identified to species according to existing keys and descriptions. a total of 13 helminth species were found representi ...200918704740
effects of sheep and cattle alternate grazing on sheep parasitism and production.production of sheep (nursing ewes) grazing alternately with cattle (growing weaned heifers) was compared to the production of sheep or cattle grazing alone (controls). pasture production and sheep parasitism were also monitored. the herbage allowance was higher for the control heifers than for the alternate heifers, but the leaf to green material ratio (lgmr) was lower, and no difference on heifer growth was revealed (443 vs. 431g.d(-1), p = 0.54). the lgmr was higher for the alternate sheep (+3 ...200918496761
isolation and immunolocalization of a putative protective antigen (p26/23) from adult haemonchus contortus.the putative protective antigen, p26/23, from adult haemonchus contortus was isolated. a soluble extract from adult helminths obtained from the abomasa of hyperinfected (12,000 infective larvae) female manchego lambs and treated with a mixture of protease inhibitors was subjected to affinity chromatography (hexylgluthatione) to eliminate the enzyme gluthatione s-transferase. the eluate was analyzed by electrophoresis under denaturing and reducing conditions (sodium dodecyl sulfate polyacrylamide ...200918825413
immunobiological characterization of graphidium strigosum experimental infection in rabbits (oryctolagus cuniculus).an experimental infection of rabbits with a wild isolate of the gastric nematode graphidium strigosum was carried out. animals (3.5 months age) were infected with 1,000 l3 administered by bucoesophagic catheter (five rabbits) or kept as uninfected control group (five animals). the infection was maintained for 3 months. along the experimental period, some parasitological, hematological and immunological parameters were determined. prepatent period of the infection ranged from 30 to 38 days and, a ...200918830629
determination of the effective dose rate for monepantel (aad 1566) against adult gastro-intestinal nematodes in sheep.monepantel (aad 1566) is the first compound from the recently discovered amino-acetonitrile derivative (aad) class of anthelmintics to be developed for use in sheep. three dose determination studies were conducted in australia and europe to identify the therapeutic dose of monepantel, when formulated for the oral treatment of sheep, to control adult gastro-intestinal nematodes. in each study, sheep infected with various nematode species were treated with either 1.25, 2.5 or 5.0mg monepantel/kg b ...200918950633
three-dimensional reconstruction of the amphid sensilla in the microbial feeding nematode, acrobeles complexus (nematoda: rhabditida).amphid sensilla are the primary olfactory, chemoreceptive, and thermoreceptive organs in nematodes. their function is well described for the model organism caenorhabditis elegans, but it is not clear to what extent we can generalize these findings to distantly related nematodes of medical, economic, and agricultural importance. current detailed descriptions of anatomy and sensory function are limited to nematodes that recent molecular phylogenies would place in the same taxonomic family, the rha ...200919003904
identification of a thrombospondin-like immunodominant and phosphorylcholine-containing glycoprotein (gp300) in dictyocaulus viviparus and related nematodes.gp300 is a high molecular weight glycoprotein of the bovine lungworm dictyocaulus viviparus. the n-linked glycans are substituted with phosphorylcholine (pc) giving it immunomodulatory potential. gp300 is highly immunogenic and its recognition by ige antibodies is correlated with protection against infection. here we identified and characterized the protein backbone of gp300. mass spectrometric analysis on purified gp300 and dna sequencing of the corresponding gene indicated that gp300 is a thro ...200919007821
haemonchus contortus and trichostrongylus colubriformis did not adapt to long-term exposure to sheep that were genetically resistant or susceptible to nematode infections.we tested the hypothesis that haemonchus contortus and trichostrongylus colubriformis would adapt to long-term exposure to sheep that were either genetically resistant or susceptible to h. contortus. sheep genotypes were from lines with 10 years prior selection for low (resistant, r) or high (susceptible, s) faecal worm egg count (wec) following h. contortus infection. long-term exposure of h. contortus and t.colubriformis to r or s genotypes was achieved using serial passage for up to 30 nemato ...200919027020
effect of plant trichomes on the vertical migration of haemonchus contortus infective larvae on five tropical forages.the influence of trichomes on vertical migration and survival of haemonchus contortus infective larvae (l3) on different forages was investigated. four different forages showing different distributions of trichomes (brachiaria brizantha cv. marandu, brachiaria brizantha cv. xaraes, andropogon gayanus, and stylosanthes spp.), and one forage species without trichomes (panicum maximum cv. tanzania), were used. forages cut at the post-grazing height were contaminated with faeces containing l3. sampl ...200918975119
exploring transcriptional conservation between ancylostoma caninum and haemonchus contortus by oligonucleotide microarray and bioinformatic analyses.in this study, we identified, using an established oligonucleotide microarray platform for the parasitic nematode haemonchus contortus, transcripts that are 'conserved' between serum-activated and non-activated l3s of ancylostoma caninum (al3 and l3, respectively) and h. contortus by cross-species hybridization (csh) at high stringency and conducted extensive bioinformatic analyses of the cross-hybridizing expressed sequence tags (ests). the microarray analysis revealed significant differential ...200918977290
anthelmintic activity of cocos nucifera l. against sheep gastrointestinal nematodes.the development of anthelmintic resistance has made the search for alternatives to control gastrointestinal nematodes of small ruminants imperative. among these alternatives are several medicinal plants traditionally used as anthelmintics. this work evaluated the efficacy of cocos nucifera fruit on sheep gastrointestinal parasites. the ethyl acetate extract obtained from the liquid of green coconut husk fiber (lgchf) was submitted to in vitro and in vivo tests. the in vitro assay was based on eg ...200919042088
anthelmintic activity of cyclotides: in vitro studies with canine and human hookworms.hookworm infection is a leading cause of maternal and child morbidity in countries of the tropics and subtropics, as well as being an important parasite in companion-animal medicine. the cyclotides are a novel family of cyclic cystine knot containing peptides from plants that have been shown to possess anthelmintic activity against haemonchus contortus and trichostrongylus colubriformis, two important gastrointestinal nematodes of sheep. in the current study we demonstrated the in vitro effects ...200919059189
availability of gastro-intestinal nematode larvae to sheep following winter contamination of pasture with six nematode species on the northern tablelands of new south wales.this experiment was designed to determine the infective consequences of winter pasture contamination by sheep infected with 6 species of trichostrongylid gastro-intestinal nematode (gin) at armidale in the new england region of nsw. ten helminthologically inert pasture plots were contaminated using 'donor' sheep harbouring artificial infections of haemonchus contortus, trichostrongylus colubriformis, trichostrongylus vitrinus, trichostrongylus axei, nematodirus spathiger and teladorsagia circumc ...200919070435
anthelmintic activity of extracts of artemisia absinthium against ovine nematodes.the increasing prevalence of anthelmintic resistant strains of helminths, drug residues in animal products and high cost of conventional anthelmintics has created an interest in studying medicinal plants as an alternative source of anthelmintics. artemisia absinthium linn. (tethwen) is used traditionally by people as a vermifuge in addition to its other livestock uses. the objective of this study was to evaluate the anthelmintic efficacy of crude aqueous extracts (cae) and crude ethanolic extrac ...200919070963
evaluation of the efficacy of anthelmintics sold on ethiopian markets against haemonchus contortus in experimentally infected sheep.a total of 54 lambs, aged between 6-8 months were experimentally infected with haemonchus contortus to evaluate the efficacy of different anthelmintic brands sold on ethiopian markets using the faecal egg count reduction test (fecrt) and controlled anthelmintic efficacy trial. accordingly four different albendazole (alzole, analgon-300, albenjung_s and ahshialben-300), two tetramisole (tetsole and ashitetra 600) and two tetramisole-oxyclozanide (tetraclozan sheep and tetraclozash 900) brands wer ...200919082869
genotyping of benzimidazole susceptible and resistant alleles in different populations of haemonchus contortus from himalayan and sub-himalayan regions of north-west india.an allele-specific pcr was standardized to diagnose the mutation (phe to try) at residue 200 of the isotype 1 beta tubulin gene responsible for benzimidazole resistance in haemonchus contortus adult and infective larvae. adult and infective larvae of haemonchus contortus were collected from sheep under different managemental practices (intensive and extensive) in temperate himalayan regions (mukteshwar and kedarkhatta), sub-himalayan region (pantnagar) of uttarakhand state and subtropical region ...200919101817
comparison of two versions of larval development test to detect anthelmintic resistance in haemonchus contortus.larval development (ldt) and micro-agar larval development tests (maldt) were used to compare the reliability and sensitivity of two methods for detecting anthelmintic resistance in haemonchus contortus. the tests were conducted using three resistant and four susceptible isolates of h. contortus. both versions of the tests provided comparable results with regard to the characterization of benzimidazole and levamisole susceptibility but neither test was sufficiently sensitive to discrimination be ...200919110379
a unique thioredoxin of the parasitic nematode haemonchus contortus with glutaredoxin activity.the dependency of parasites on the cellular redox systems has led to their investigation as novel drug targets. defence against oxidative damage is through the thioredoxin and glutathione systems. the classic thioredoxin is identified by the active site cys-gly-pro-cys (cgpc). here we describe the identification of a unique thioredoxin in the parasitic nematode, haemonchus contortus. this thioredoxin-related protein, termed hctrx5, has an arginine in its active site (cys-arg-ser-cys; crsc) that ...200919111609
fmrfamide-like neuropeptides as putative ligands of the latrophilin-like hc110-r from haemonchus contortus.the latrophilin-like receptor hc110-r of the parasitic nematode haemonchus contortus has been previously identified as a target for the novel anthelmintic drug emodepside, but the natural ligand(s) remained completely unknown to date. here, we investigate 11 different fmrfamide-like neuropeptides as putative ligands by surface plasmon resonance with an immobilized recombinant 54kda aminoterminal fragment of hc110-r as an interaction partner. af1, af10 and pf2 exhibit binding with low affinities ...200919126419
dose confirmation studies for monepantel, an amino-acetonitrile derivative, against fourth stage gastro-intestinal nematode larvae infecting sheep.monepantel is the first compound from the recently discovered amino-acetonitrile derivative (aad) class of anthelmintics to be developed for use in sheep. nine dose confirmation studies were conducted in australia, new zealand and switzerland to confirm the minimum therapeutic oral dose of monepantel to control fourth stage (l4) gastro-intestinal nematode larvae in sheep (target species were haemonchus contortus, teladorsagia (ostertagia) circumcincta, teladorsagia trifurcata, trichostrongylus a ...200919135310
in vitro effects of cucurbita moschata seed extracts on haemonchus contortus.this study was carried out to evaluate the in vitro effect of cucurbita moschata seed against the parasitic nematode of small ruminants haemonchus contortus. three extracts (aqueous, methanolic and dichloromethane) of c. moschata seed were tested in vitro on four developmental stages of h. contortus using egg hatch assay (eha), larval development assay (lda), l3 migration inhibition (lmi) assay and adult worm motility (awm) assay. the highly significant (p<0.001) ability to stop larval developme ...200919135803
evaluation of the famacha system for detecting the severity of anaemia in sheep from southern italy.since it was first developed in south africa, the famacha system has been successfully tested in different geographic area where haemonchus contortus is the major gastrointestinal (gi) strongyle species of sheep. the present study, the first on the use of the famacha system in italy, was aimed at obtaining a complete haematological profile in sheep with gi strongyle infection, in order to evaluate the validity of the famacha system for detecting the severity of anaemia in sheep from southern ita ...200919153013
molecular detection of benzimidazole resistance in haemonchus contortus using real-time pcr and pyrosequencing.benzimidazoles (bz) are widely used to treat parasitic nematode infections of humans and animals, but resistance is widespread in veterinary parasites. several polymorphisms in beta-tubulin genes have been associated with bz-resistance. in the present study, we investigated beta-tubulin isotype 1 sequences of 18 haemonchus contortus isolates with varying levels of resistance to thiabendazole. the only polymorphism whose frequency was significantly increased in the resistant isolates was ttc to t ...200919154653
anthelmintic resistance in swedish sheep flocks based on a comparison of the results from the faecal egg count reduction test and resistant allele frequencies of the beta-tubulin gene.a faecal egg count reduction test (fecrt) survey was conducted during the grazing season 2006 and 2007 to provide an updated indication of the prevalence of anthelmintic resistance in sheep flocks in sweden. a total of 1330 faecal samples from 90 flocks on 45 farms, with a minimum of 20 ewes each, was collected by local sheep veterinarians. per treatment group, approximately 15 lambs were dewormed either with oral suspensions of ivermectin (ivomec vet.) or albendazole (valbazen vet.). the effica ...200919155135
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