Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| an ivermectin-sensitive glutamate-gated chloride channel from the parasitic nematode haemonchus contortus. | nematode glutamate-gated chloride channels are targets of the macrocyclic lactones, the most important group of anthelmintics available. in xenopus laevis oocytes, channels formed by the gluclalpha3b subunit from the parasite haemonchus contortus were more sensitive to l-glutamate (ec(50) = 27.6 +/- 2.7 microm) than those formed by the homologous subunit from caenorhabditis elegans (ec(50) = 2.2 +/- 0.12 mm). ibotenate was a partial agonist (ec(50) = 87.7 +/- 3.5 microm). the h. contortus channe ... | 2009 | 19336526 |
| microarray analysis reveals difference in gene expression profiles of hair and wool sheep infected with haemonchus contortus. | sheep infected with the abomasal parasite, haemonchus contortus, have reduced growth rates, decreased wool production, and anemia, and heavy infections may result in death. anthelmintic treatment can remove worms, but the cost of treatment and prevalence of drug-resistant worms has led to greater focus on genetic resistance of the host to parasitism. variation in parasite resistance exists within and among sheep breeds, and caribbean hair sheep have greater resistance than most conventional wool ... | 2009 | 19346008 |
| the potential to control haemonchus contortus in indigenous south african goats with copper oxide wire particles. | the high prevalence of resistance of haemonchus contortus to all major anthelmintic groups has prompted investigations into alternative control methods in south africa, including the use of copper oxide wire particle (cowp) boluses. to assess the efficacy of cowp against h. contortus in indigenous south african goats, 18 male faecal egg-count-negative goats were each given ca.1200 infective larvae of h. contortus three times per week during weeks 1 and 2 of the experiment. these animals made up ... | 2009 | 19346076 |
| ultraviolet light increases mortality of nematode larvae and can explain patterns of larval availability at pasture. | despite its documented effects on the viability of living organisms, the impact of ultraviolet (uv) light on the survival of parasitic nematode larvae has received surprisingly little attention. infective l3s of the trichostrongyloid nematodes haemonchus contortus, teladorsagia circumcinta and nematodirus battus, suspended in water, were exposed to direct uv irradiation in two experiments. in the first, during 6 days of constant illumination with uva lamps at intensities simulating sunlight at g ... | 2009 | 19358849 |
| haemonchus contortus acetylcholine receptors of the deg-3 subfamily and their role in sensitivity to monepantel. | gastro-intestinal nematodes in ruminants, especially haemonchus contortus, are a global threat to sheep and cattle farming. the emergence of drug resistance, and even multi-drug resistance to the currently available classes of broad spectrum anthelmintics, further stresses the need for new drugs active against gastro-intestinal nematodes. a novel chemical class of synthetic anthelmintics, the amino-acetonitrile derivatives (aads), was recently discovered and the drug candidate aad-1566 (monepant ... | 2009 | 19360096 |
| [the prevalence of gastro-intestinal nematodes in hair goats of the sanliurfa region]. | the aim of this study was to determine the prevalence of gastro-intestinal nematodes in hair goats in sanliurfa region between november 2005 and november 2006. during this period, the alimentary canal from 1 or 2 goats was obtained from the municipal slaughterhouse each week. these were brought into the laboratory and examined for the presence of nematodes. gastro-intestinal tracts of 100 hair goats were examined. of these, 83 (83%) were found infected with nematodes. twenty nematode species wer ... | 2009 | 19367541 |
| anthelmintic resistant haemonchus contortus in a giraffe (giraffa camelopardalis) in florida. | a young male giraffe (giraffa camelopardalis) recently acquired by the lion country safari in loxahatchee, florida, was diagnosed and successfully treated for haemonchus infection while in quarantine. seven weeks after introduction into a group of resident giraffes, this giraffe presented with diarrhea. fecal evaluation revealed an extremely high count of 16,700 eggs/g, with larval identification of the parasite as haemonchus. a larval development assay showed resistance to the three classes of ... | 2009 | 19368252 |
| frequency of treatment and production performance using the famacha method compared with preventive control in ewes. | the rapid escalation of anthelmintic resistance in parasites suggests the adoption of different strategies for parasite control in small ruminants instead of relying only on the use of chemicals. the integrated system of parasite control (sicopa) program uses the famacha method, which is used to separately identify sheep that are resistant/resilient or susceptible to haemonchus contortus, or together with other management practices, such as pasture rotation or the monitoring of drug efficacy. th ... | 2009 | 19369007 |
| impact of rotational grazing on management of gastrointestinal nematodes in weaned lambs. | gastrointestinal nematode (gin) control for 'natural' or organic lamb production is needed, especially where haemonchus contortus is prevalent. the objective was to determine the impact of rotational grazing on gin infection of weaned lambs. in year 1, naturally infected katahdin lambs (120 days of age) were randomly assigned to graze (1) continuous bermudagrass (cb; n=14), (2) rotational bermudagrass moved every 3.5 days and returned to original plot 35 days later for three rotations (rb; n=14) ... | 2009 | 19394147 |
| an ac-5 cathepsin b-like protease purified from haemonchus contortus excretory secretory products shows protective antigen potential for lambs. | the immunogenic properties of cysteine proteases obtained from excretory/secretory products (es) of haemonchus contortus were investigated with a fraction purified with a recombinant h. contortus cystatin affinity column. the enrichment of h. contortus es for cysteine protease was confirmed with substrate sds-page gels since the cystatin-binding fraction activity was three times higher than total es, despite representing only 3% of total es. this activity was inhibited by a specific cysteine pro ... | 2009 | 19401141 |
| functional genomics of hsp-90 in parasitic and free-living nematodes. | heat shock protein 90 (hsp-90) is a highly conserved essential protein in eukaryotes. here we describe the molecular characterisation of hsp-90 from three nematodes, the free-living caenorhabditis elegans (ce) and the parasitic worms brugia pahangi (bp) and haemonchus contortus (hc). these molecules were functionally characterised by rescue of a ce-daf-21 (hsp-90) null mutant. our results show a gradient of rescue: the c. elegans endogenous gene provided full rescue of the daf-21 mutant, while h ... | 2009 | 19401205 |
| a th2 type of immune response is associated with increased resistance to haemonchus contortus in naturally infected gulf coast native lambs. | haemonchus contortus is one of the major nematode parasites causing substantial economic losses in small ruminant farming worldwide. recently, effectiveness of anthelmintic treatment has decreased due to an increasing problem of nematode populations that have developed resistance to anthelmintics. efforts to develop effective vaccines have had limited success. there are certain breeds of sheep that are relatively resistant to the parasite including gulf coast native (native) sheep. understanding ... | 2009 | 19406579 |
| is gastrointestinal strongyle faecal egg count influenced by hour of sample collection and worm burden in goats? | gastrointestinal (gi) strongyle infections remain one of the main constraints to goat production worldwide. although several indicators of gi strongyle infections have been proposed, faecal egg count (fec) techniques are the most common approaches for the estimation of prevalence and intensity of these parasites. however, fec may be subjected to a within-individual variation due to factors such as weather, season, random day-to-day variation and phase of the parasitic infection. a longitudinal s ... | 2009 | 19414222 |
| a survey on meat sheep farms in two regions of morocco on farm structure and the acceptability of the targeted selective treatment approach to worm control. | sheep production is very important in morocco and two regions (chaouia plain and semi-mountainous middle-atlas) play a significant role in this production. ten farms were investigated for nematode species and resistance each region. pooled material from each region provided evidence of benzimidazole resistance in teladorsagia in both regions; haemonchus contortus was resistant in the chaouia only. forty eight farms in chaouia and 27 farms in middle-atlas were given questionnaires in order to cha ... | 2009 | 19419816 |
| mapping the complement c1q binding site in haemonchus contortus calreticulin. | haemonchus contortus is an economically important gastrointestinal parasite of domestic animals. the parasite secretes calreticulin (calr), a ca(++) binding protein which modulates the host immune response. one way by which this protein acts is by inhibiting the classical complement pathway by binding to complement c1q protein. understanding calr-c1q interaction is important to develop methods to enhance host immune response. in this study, we have mapped the regions in the n-domain of calr that ... | 2009 | 19428671 |
| a dopamine-gated ion channel (hcggr3*) from haemonchus contortus is expressed in the cervical papillae and is associated with macrocyclic lactone resistance. | haemonchus contortus, a parasitic nematode of great economic importance, is a major challenge for the livestock industries. the parasite is controlled by nematocidal drugs, several of which target ligand-gated chloride channels (lgccs). in addition, drug resistance has become a major problem in controlling this parasite and other trichostrongylids. therefore, identification of new drug targets may assist in the discovery of novel drugs which is essential for maintaining the level of parasite con ... | 2009 | 19428673 |
| anthelmintic activity of ziziphus nummularia (bark) and acacia nilotica (fruit) against trichostrongylid nematodes of sheep. | ziziphus nummularia (rhamnaceae) and acacia nilotica (fabaceae) are being used as anthelmintics in ethnoveterinary medicinal system of pakistan. | 2009 | 19429379 |
| influence of earthworms on development of the free-living stages of gastrointestinal nematodes in goat faeces. | with the important infection of small ruminants by gastrointestinal nematodes, and in the face of reduced efficacy of anthelminthic treatments, a search for other biological options is necessary. the effect of earthworms on the free-living stages of haemonchus contortus and trichostrongylus colubriformis in faeces from goats naturally infected in tropical pastures was evaluated. two levels (0 vs 14 individuals per container) of indigenous earthworms (50% pontoscolex corethrus and 50% perionyx ex ... | 2009 | 19443123 |
| standardization of the egg hatch test for the detection of benzimidazole resistance in parasitic nematodes. | the ability to reliably detect anthelmintic resistance is a crucial part of resistance management. if data between countries are to be compared, the same test should give the same results in each laboratory. as the egg hatch test for benzimidazole resistance is used for both research and surveys, the ability of different laboratories to obtain similar results was studied through testing of known isolates of cyathostomins, haemonchus contortus, ostertagia ostertagi, and cooperia oncophora in prog ... | 2009 | 19452165 |
| resistance of different fungal structures of duddingtonia flagrans to the digestive process and predatory ability on larvae of haemonchus contortus and strongyloides papillosus in goat feces. | the dynamics of the passage of conidia, chlamydospores, and mycelia of the fungus duddingtonia flagrans through the digestive tracts of goats was evaluated. four groups with five goats each were formed. in the group conidia, each animal received 1 x 10(6) d. flagrans conidia per kilogram of live weight. in the group chlamydospore, each animal received 1 x 10(6) chlamydospores per kilogram of live weight. in the group mycelia, each animal received 1 g of mycelium mass per kilogram of live weight. ... | 2009 | 19471967 |
| mechanical recovery of inhibited cyathostomin larvae from equine intestinal tissue. | the stomacher is very widely used in food and medical research for extracting tissues. to determine whether nematode larvae were disrupted by the stomacher, l3 larvae of haemonchus contortus were homogenised for up to 40 min at full power but no larval disruption occurred. therefore, tissue from the mucosa and submucosa of the caecum of horses collected from a licenced abattoir was treated to determine whether inhibited cyathostomin larvae could be extracted. the optimum time on full power for a ... | 2009 | 19479280 |
| exploring the anthelmintic properties of australian native shrubs with respect to their potential role in livestock grazing systems. | we measured in vitro anthelmintic activity in extracts from 85 species of australian native shrub, with a view to identifying species able to provide a degree of worm control in grazing systems. approximately 40% of the species showed significant activity in inhibiting development of haemonchus contortus larvae. the most active extracts showed ic50 values of 60-300 microg/ml. pre-incubation with polyvinylpolypyrrolidine removed the activity from some extracts, implicating tannins as the bioactiv ... | 2009 | 19523255 |
| the relationship between the rapid rejection of haemonchus contortus larvae with cells and mediators in abomasal tissues in immune sheep. | rapid rejection or immune exclusion of challenge larvae is a well recognised phenomenon in sheep hypersensitised by repeated infection with gastrointestinal nematodes. while mast cells and globule leukocytes (gls) are typically associated with this rapid rejection response, the exact mechanisms and mediators involved are not known. this study has adapted a recently developed ex vivo tissue explant model to examine in more detail the cells and mediators involved in preventing establishment of hae ... | 2009 | 19540240 |
| p-glycoprotein interfering agents potentiate ivermectin susceptibility in ivermectin sensitive and resistant isolates of teladorsagia circumcincta and haemonchus contortus. | p-glycoprotein (p-gp) homologues, belonging to the atp binding cassette (abc) transporter family, are thought to play an important role in the resistance of gastro-intestinal nematode parasites against macrocyclic lactones. the aim of this study was to investigate the influence of various p-gp interfering compounds on the efficacy of ivermectin (ivm) in sensitive and resistant nematode isolates. the feeding of ivm resistant and sensitive teladorsagia circumcincta and haemonchus contortus first-s ... | 2009 | 19549355 |
| sheep helminth parasitic disease in south eastern scotland arising as a possible consequence of climate change. | the climate in the uk is changing, with a trend towards increased rainfall in the autumn and winter and warmer average temperatures throughout the year. there has also been a 4-week extension of the herbage growing season over the past 40 years. these changes may have implications for the epidemiology of sheep helminth parasites. here, we describe production-limiting disease outbreaks caused by haemonchus contortus, nematodirus battus, teladorsagia circumcincta and fasciola hepatica in sheep flo ... | 2009 | 19556065 |
| 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 ... | 2009 | 18825413 |
| 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 ... | 2009 | 18830629 |
| 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 ... | 2009 | 19003904 |
| 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 ... | 2009 | 19007821 |
| 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 ... | 2009 | 19027020 |
| 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 ... | 2009 | 18950633 |
| 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 ... | 2009 | 18516697 |
| 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 ... | 2009 | 18704740 |
| immunoproteomic analysis of whole proteins from male and female adult haemonchus contortus. | whole proteins of male and female adult haemonchus contortus were analysed by immunoproteomic techniques. approximately 662 and 680 spots were detected on proteome maps of male and female nematodes, respectively, stained with coomassie brilliant blue g-250. there were 609 shared spots. approximately 193 and 196 spots were recognised on western blot maps of male and female nematodes, respectively, using antiserum from naturally infected goats as the source of primary antibodies. there were 129 ge ... | 2010 | 19560953 |
| structural and functional characterisation of the fork head transcription factor-encoding gene, hc-daf-16, from the parasitic nematode haemonchus contortus (strongylida). | despite their phylogenetic diversity, parasitic nematodes share attributes of longevity and developmental arrest (=hypobiosis) with free-living nematodes at key points in their life cycles, particularly in larval stages responsible for establishing infection in the host. insulin-like signalling plays crucial roles in the regulation of life span and arrest (=dauer formation) in the free-living nematode, caenorhabditis elegans. insulin-like signalling in c. elegans negatively regulates the fork he ... | 2010 | 19796644 |
| expression of genes in gastrointestinal and lymphatic tissues during parasite infection in sheep genetically resistant or susceptible to trichostrongylus colubriformis and haemonchus contortus. | resistance to an acute gastrointestinal nematode (gin) infection is dependent on the ability of the host to recognise the parasite and mount a protective th2 response. it is hypothesised that lambs which are genetically susceptible to gin will differentially up-regulate th1-type genes and therefore remain susceptible to chronic parasitism compared with genetically resistant lambs which will differentially up-regulate th2-type genes and clear the parasite infection. two selection flocks, in which ... | 2010 | 19825375 |
| the use of dna markers to map anthelmintic resistance loci in an intraspecific cross of haemonchus contortus. | the use of dna markers to track the development of anthelmintic resistance in parasites of livestock would allow informed choices for the management of this important problem. we describe a genetic mapping approach for the discovery of dna markers for anthelmintic resistance in haemonchus contortus. we crossed a multi-drug resistant field isolate of h. contortus with a well-characterized laboratory strain susceptible to 4 drug classes. the f2 were separately selected with 5 anthelmintics from 4 ... | 2010 | 19835651 |
| elucidating ants in worms using genomic and bioinformatic tools--biotechnological prospects? | adenine nucleotide translocators (ants) belong to the mitochondrial carrier family (mcf) of proteins. atp production and consumption are tightly linked to ants, the kinetics of which have been proposed to play a key regulatory role in mitochondrial oxidative phosphorylation. ants are also recognized as a central component of the mitochondrial permeability transition pore associated with apoptosis. although ants have been investigated in a range of vertebrates, including human, mouse and cattle, ... | 2010 | 19770033 |
| multiple anthelmintic resistance and the possible contributory factors in beetal goats in an irrigated area (pakistan). | this paper presents the first report of multiple anthelmintic resistance in the gastrointestinal nematodes of goats and its possible contributory factors in an irrigated area (pakistan). a total of 18 privately owned beetal goat flocks were selected in order to determine the anthelmintic resistance against commonly used anthelmintics. forty to 48 animals from each flock were selected according to their weight and egg count. the three anthelmintics viz., oxfendazole, levamisole and ivermectin, we ... | 2010 | 19733870 |
| daf-7-related tgf-beta homologues from trichostrongyloid nematodes show contrasting life-cycle expression patterns. | the transforming growth factor-beta (tgf-beta) gene family regulates critical processes in animal development, and plays a crucial role in regulating the mammalian immune response. we aimed to identify tgf-beta homologues from 2 laboratory model nematodes (heligmosomoides polygyrus and nippostrongylus brasiliensis) and 2 major parasites of ruminant livestock (haemonchus contortus and teladorsagia circumcincta). parasite cdna was used as a template for gene-specific pcr and race. homologues of th ... | 2010 | 19712539 |
| the kunitz domain protein bli-5 plays a functionally conserved role in cuticle formation in a diverse range of nematodes. | the cuticle of parasitic nematodes performs many critical functions and is essential for proper development and for protection from the host immune response. the biosynthesis, assembly, modification and turnover of this exoskeleton have been most extensively studied in the free-living nematode, caenorhabditis elegans, where it represents a complex multi-step process involving a whole suite of enzymes. the biosynthesis of the cuticle has an additional level of complexity, as many of the enzymes a ... | 2010 | 19716386 |
| gastro-intestinal nematode infections in goats relative to season, host sex and age from the kashmir valley, india. | the present study aimed to investigate the seasonal epidemiological prevalence of gastro-intestinal nematodes (gins) of goats with respect to sex and age of the host in the kashmir valley from 1 february 2005 to 31 january 2007. a total of 1267 goats were examined [faecal examination: 938 (year 1: 470; year 2: 468); gastro-intestinal (git) examination: 329 (year 1: 175; year 2: 154)]. the overall prevalence of gin infection in these animals was 54.3% (year 1: 54.8%; year 2: 53.8%; p = 0.842). th ... | 2010 | 19627625 |
| in-vitro anthelminthic activity of crude aqueous extracts of aloe ferox, leonotis leonurus and elephantorrhiza elephantina against haemonchus contortus. | aloe ferox (mill), leonotis leonurus (l) r. br; and elephantorrhiza elephantina (burch.) skeels are plants frequently used by resource-limited farmers in the eastern cape province to control gastrointestinal parasites in goats. a study was conducted to validate their anthelminthic activities in-vitro on the egg and larvae of the nematode parasite haemonchus contortus. the crude aqueous extracts of leaves of a. ferox and l. leonurus; and roots of e. elephantina were used. eggs and larvae of the p ... | 2010 | 19693685 |
| vaccination-induced igg response to galalpha1-3galnac glycan epitopes in lambs protected against haemonchus contortus challenge infection. | lambs vaccinated with haemonchus contortus excretory/secretory (es) glycoproteins in combination with the adjuvant alhydrogel are protected against h. contortus challenge infection. using glycan micro-array analysis we showed that serum from such vaccinated lambs contains igg antibodies that recognise the glycan antigen galalpha1-3galnac-r and galnacbeta1-4(fucalpha1-3)glcnac-r. our studies revealed that h. contortus glycoproteins contain galalpha1-3gal-r as well as significant levels of galalph ... | 2010 | 19695255 |
| anthelmintic effects of prosopis laevigata n-hexanic extract against haemonchus contortus in artificially infected gerbils ( meriones unguiculatus). | the anthelmintic effect of prosopis laevigata (mezquite) n-hexanic extract was evaluated against haemonchus contortus endoparasitic stages in artificially infected gerbils (meriones unguiculatus). prosopis laevigata leaves were collected from the sierra de huautla, ecological reserve of the biosphere, in morelos state, mexico; dehydrated under shade and macerated with n-hexane for 3 days, followed by distillation for 8 h. this procedure was repeated three times and the final extract was kept at ... | 2010 | 19619382 |
| efficacy of copper oxide wire particles against gastrointestinal nematodes in sheep and goats. | profitable sheep and goat production in the usa is severely limited by gastrointestinal nematode (gin) parasitism, particularly by haemonchus contortus. copper oxide wire particles (cowp) have anti-parasitic properties in the diet of small ruminants, but efficacy of cowp may differ between sheep and goats. in a study with weaned kids (kiko x spanish cross, 6 months old) and lambs (katahdin or dorper x blackface crosses, 5 months old), grazing the same pasture area in central georgia, 2g of cowp ... | 2010 | 19931291 |
| cdna-aflp analysis in levamisole-resistant haemonchus contortus reveals alternative splicing in a nicotinic acetylcholine receptor subunit. | the cdna-aflp (cdna-amplified fragment length polymorphism) method comparing transcripts from levamisole-resistant and susceptible haemonchus contortus isolates has led to the successful identification of a number of potentially useful levamisole-resistance markers. in the present study, we report the characterization of the transcript-derived fragment (tdf) named hax which was confirmed to be specifically expressed in three levamisole-resistant isolates by rt-pcr experiments. cloning and sequen ... | 2010 | 19932716 |
| evaluation of three pakistani sheep breeds for their natural resistance to artificial infection of haemonchus contortus. | this study was carried out to evaluate three pakistani sheep breeds (kachhi, lohi and thalli) for their natural resistance against artificial infection of haemonchus contortus. lambs were weaned at 3 months of age, housed in separate pens and treated with avermectin to eliminate gastrointestinal nematode infection. each lamb was infected orally with approximately 10,000 third stage larvae of h. contortus. selected breeds were compared on the basis of parasitological, haematological, biochemical ... | 2010 | 19939567 |
| administration of copper oxide wire particles in a capsule or feed for gastrointestinal nematode control in goats. | widespread anthelmintic resistance in small ruminants has necessitated alternative means of gastrointestinal nematode (gin) control. the objective was to determine the effectiveness of copper oxide wire particles (cowp) administered as a gelatin capsule or in a feed supplement to control gin in goats. in four separate experiments, peri-parturient does (n=36), yearling does (n=25), weaned kids (n=72), and yearling bucks (n=16) were randomly assigned to remain untreated or administered 2g cowp in ... | 2010 | 19945224 |
| alterations in the expression level of a putative aspartic protease in the development of angiostrongylus cantonensis. | aspartic proteases are a family of proteinases with catalytic aspartate residues in the active site. these enzymes have been reported to initialize the degradation of host hemoglobin in blood-feeding helminths. after identifying an expressed sequence tag representing an aspartic protease from an angiostrongylus cantonensis young adult dataset, this sequence was found to encode a protein with a predicted molecular mass of 46 kda. it also showed good homologies to aspartic proteases from caenorhab ... | 2010 | 19945419 |
| overcoming macrocyclic lactone resistance in haemonchus contortus with pulse dosing of levamisole. | the in vivo effect of dosing levamisole as a pulse release within an ivermectin (ivm) controlled-release device (crd) was simulated by periodic dosing of levamisole to haemonchus contortus-infected sheep already treated with an ivm crd. the rationale for this treatment combination arises from the need to find alternative approaches to the treatment of gastrointestinal parasites in livestock in the face of increasing levels of anthelmintic resistance which is now widespread in australia. thirty m ... | 2010 | 19959294 |
| anthelmintic activity of some mediterranean browse plants against parasitic nematodes. | the anthelmintic properties of tannin-rich plants are being explored as an alternative to chemical drugs. most data have been acquired on legume forages, but only few on browse plants. the present study aimed to (i) screen the in vitro effects of extracts from 7 mediterranean plants on haemonchus contortus, (ii) verify the role of tannins using an inhibitor, polyvinyl polypyrrolidone (pvpp) and (iii) verify the in vivo effects of extracts from 4 plants. significant inhibition was shown in vitro ... | 2010 | 19961649 |
| in vivo anthelmintic activity of azadirachta indica a. juss seeds against gastrointestinal nematodes of sheep. | this paper describes the in vivo anthelmintic activity of azadirachta indica seeds to justify their use in south-asia by traditional animal healers. seeds of a. indica were administered as crude powder (cp), crude aqueous (cae) and crude methanolic extracts (cme) at the doses of 1 and 3g/kg of body weight to sheep naturally infected with mixed species of gastrointestinal nematodes. the study design also included untreated as well as treated controls. faecal egg count reduction and larval counts ... | 2010 | 19963323 |
| effect of feeding mucuna pruriens on helminth parasite infestation in lambs. | mucuna pruriens is a tropical legume anecdotally reputed to have anthelmintic properties. this study was conducted to examine the validity of such claims. | 2010 | 19969060 |
| design and synthesis of novel insecticides based on the serotonergic ligand 1-[(4-aminophenyl)ethyl]-4-[3-(trifluoromethyl)phenyl]piperazine (papp). | 1-[(4-aminophenyl)ethyl]-4-[3-(trifluoromethyl)phenyl]piperazine (papp) is a 5-ht(1a) agonist and was reported to display high affinity for serotonin (5-ht) receptor from the parasitic nematode haemonchus contortus . the present investigation explored the possibility of using papp as a lead compound of new insecticides with novel mode of action. on the basis of the papp scaffold, a series of 1-arylmethyl-4-[(trifluoromethyl)pyridin-2-yl]piperazine derivatives were designed, synthesized, and eval ... | 2010 | 20000410 |
| nematode challenge induces differential expression of oxidant, antioxidant and mucous genes down the longitudinal axis of the sheep gut. | to characterize the role of a range of oxidant, antioxidant and mucous-related genes in the primary response to gastrointestinal nematodes, groups of genetically resistant sheep were challenged with either haemonchus contortus or trichostrongylus colubriformis and necropsied for retrieval of tissue at days 0, 3, 7, 14 and 21. to determine if the response was localized to the site of parasite infection, four different gut tissues were sampled: the abomasum, proximal and distal jejunum and ileum. ... | 2010 | 20042006 |
| the effect of sheep breed, age, and gender on the pharmacokinetics and efficacy of monepantel, an amino-acetonitrile derivative. | this analysis investigated the influence of breed and gender on the pharmacokinetics of monepantel, and influence of breed, age, and gender on its efficacy against gastrointestinal nematodes of sheep. in a comparison of pharmacokinetic profiles from two studies, merino lambs had significantly greater maximum concentrations of monepantel and monepantel sulfone, and faster times to reach these concentrations than dorset cross lambs. males had a statistically greater area under the curve (0-504 h) ... | 2010 | 19898870 |
| estimates of genetic parameters for faecal egg count of haemonchus contortus infection and relationship with growth traits in avikalin sheep. | genetic parameters for faecal egg count were estimated in naturally challenged avikalin sheep developed and maintained at central sheep & wool research institute, avikanagar, india, over a period of 4 years (2004-2007). the data on faecal egg count for 433 animals descended from 41 sires, and 151 dams were used for the study. genetic analyses were carried out using restricted maximum likelihood, fitting an animal model and ignoring or including maternal genetic or permanent environmental effects ... | 2010 | 19898999 |
| collagen processing and cuticle formation is catalysed by the astacin metalloprotease dpy-31 in free-living and parasitic nematodes. | the exoskeleton or cuticle performs many key roles in the development and survival of all nematodes. this structure is predominantly collagenous in nature and requires numerous enzymes to properly fold, modify, process and cross-link these essential structural proteins. the cuticle structure and its collagen components are conserved throughout the nematode phylum but differ from the collagenous matrices found in vertebrates. this structure, its formation and the enzymology of nematode cuticle co ... | 2010 | 19883650 |
| genetic variability of haemonchus contortus (nematoda: trichostrongyloidea) in alpine ruminant host species. | genetic variability of the ovine parasite haemonchus contortus from the alpine area was investigated using mitochondrial dna (nd4 gene), internal transcribed spacers 1 and 2 and microsatellites, in order to assess whether cross-transmission between domestic and wild ruminants occurs. the dataset was composed of 78 individual adult male h. contortus collected from chamois (rupicapra r. rupicapra), roe deer (capreolus capreolus), alpine ibex (capra ibex ibex), domestic goat (capra hircus) and shee ... | 2010 | 19889245 |
| modification and further evaluation of a fluorescein-labeled peanut agglutinin test for identification of haemonchus contortus eggs. | gastrointestinal nematodes of the family trichostrongylidae are the most important parasites of sheep, goats and other ruminants worldwide. of this group, haemonchus contortus is usually the most damaging species, particularly in warmer climates or during the summer. it is therefore useful to be able to rapidly differentiate infections with this nematode from other, less pathogenic, species. however, aside from nematodirus spp., there are only subtle differences between the egg morphology within ... | 2010 | 20060646 |
| protein acyltransferase function of purified calreticulin. part 1: characterization of propionylation of protein utilizing propoxycoumarin as the propionyl group donor. | we have earlier reported that an endoplasmic reticulum luminal protein calreticulin (cr) mediated the acetylation of certain receptor proteins such as glutathione s-transferase (gst) by polyphenolic acetates, leading to irreversible inhibition. this function of calreticulin was termed calreticulin transacetylase. in this communication, we have demonstrated for the first time the ability of the purified recombinant calreticulin of a parasitic nematode haemonchus contortus to transfer propionyl gr ... | 2010 | 20071373 |
| effect of repeated wattle tannin drenches on worm burdens, faecal egg counts and egg hatchability during naturally acquired nematode infections in sheep and goats. | in vivo and in vitro experiments were carried out to investigate the effect of repeated wattle tannin (wt) drenches on faecal egg counts (fec), worm burdens and egg hatchability during a naturally acquired worm infection in sheep and goats. for the in vivo experiment, nematode-infected sheep and goats were orally drenched with wt at a dose of 1.3g and 1.6gwt/kg bodyweight per day for three consecutive days respectively while a control group received a placebo. fec and other worm infection parame ... | 2010 | 20083356 |
| acetate formation in the energy metabolism of parasitic helminths and protists. | formation and excretion of acetate as a metabolic end product of energy metabolism occurs in many protist and helminth parasites, such as the parasitic helminths fasciola hepatica, haemonchus contortus and ascaris suum, and the protist parasites, giardia lamblia, entamoeba histolytica, trichomonas vaginalis as well as trypanosoma and leishmania spp. in all of these parasites acetate is a main end product of their energy metabolism, whereas acetate formation does not occur in their mammalian host ... | 2010 | 20085767 |
| in vitro anthelmintic activity of combretum molle (r. br. ex g. don) (combretaceae) against haemonchus contortus ova and larvae. | parasitic nematodes, especially haemonchus contortus (rudolphi), are among the most common and economically important causes of disease in sheep and goats owned by pastoralists and small holder farmers in africa. the control of these infections relies mainly on the use of anthelmintic drugs. however, herbal preparations are widely used by pastoralists and small holder farmers for the treatment of their livestock against helminth parasites. the anthelmintic effect of acetone leaf extract and frac ... | 2010 | 20097010 |
| lysine-scanning mutagenesis reveals an amendable face of the cyclotide kalata b1 for the optimization of nematocidal activity. | cyclotides are a family of macrocyclic peptides that combine the unique features of a head-to-tail cyclic backbone and a cystine knot motif, the combination of which imparts them with extraordinary stability. the prototypic cyclotide kalata b1 is toxic against two economically important gastrointestinal nematode parasites of sheep, haemonchus contortus and trichostrongylus colubriformis. a lysine scan was conducted to examine the effect of the incorporation of positive charges into the kalata b1 ... | 2010 | 20103593 |
| calreticulin transacylase: genesis, mechanism of action and biological applications. | our earlier investigations have identified a unique enzyme in the endoplasmic reticulum (er) termed acetoxy drug: protein transacetylase (taase) catalyzing the transfer of acetyl group from polyphenolic acetates (pa) to certain receptor proteins (rp). an elegant assay procedure for taase was developed based on the inhibition of glutathione s-transferase (gst) due to acetylation by a model acetoxycoumarin, 7, 8-diacetoxy-4-methylcoumarin (damc). taase purified from various mammalian tissue micros ... | 2010 | 20109516 |
| in vitro effects of tabernaemontana citrifolia extracts on haemonchus contortus. | tabernaemontana citrifolia (apocynaceae) is traditionally used as an anthelmintic preparation for ruminants in guadeloupe (french west indies). this study was carried out to evaluate the in vitro effect of this plant against the parasitic nematode of small ruminants haemonchus contortus. three extracts (aqueous, methanolic and dichloromethane) of t. citrifolia fruit, leaf and root were tested on four developmental stages of the parasite, using egg hatch assay (eha), larval development assay (lda ... | 2010 | 20117808 |
| vertical migration of haemonchus contortus infective larvae on cynodon dactylon and paspalum notatum pastures in response to climatic conditions. | observations were made on vertical migration patterns of haemonchus contortus infective larvae on cynodon dactylon (bermudagrass) and paspalum notatum (bahiagrass) pastures under summer climatic conditions typical of east texas. ten thousand h. contortus infective larvae (l3) were introduced to 100 cm(2) subplots of each pasture species within a plot area of 1m(2). subplots were inoculated with larvae by applying them in an aqueous medium to the soil or mat beneath the vegetation. herbage from t ... | 2010 | 20149541 |
| characterization of a caenorhabditis elegans glc seven-like phosphatase (gsp) orthologue from haemonchus contortus (nematoda). | a full-length complementary dna (cdna; designated hc-stp-1) encoding a serine/threonine phosphatase (hc-stp-1) was isolated from haemonchus contortus, a strongylid nematode parasite of small ruminants. hc-stp-1 was shown to be transcribed in males of both adults and fourth-stage larvae, but not in females, early larval stages or eggs. the full-length gene (2854 bp) contained ten exons and nine introns, and encoded a cdna of 951 bp. comparisons of the conceptually translated protein (316 amino ac ... | 2010 | 20153820 |
| the control of inhibited fourth-stage larvae of haemonchus contortus and teladorsagia spp. in sheep in australia with monepantel. | monepantel is the first molecule from the amino-acetonitrile derivatives to be developed for controlling gastro-intestinal nematodes in sheep. two studies were undertaken to examine the drug's efficacy against inhibited fourth-stage larvae of haemonchus contortus and teladorsagia spp. in sheep when administered as an oral solution at 2.5mg/kg bodyweight. in study 1, efficacy was 99.7% against h. contortus (p<0.0001) and in study 2, 99.8% against teladorsagia spp. (p<0.0001). this population cons ... | 2010 | 20153932 |
| immune cell kinetics in the ovine abomasal mucosa following hyperimmunization and challenge with haemonchus contortus. | sheep were sensitized by repeated infection with haemonchus contortus l3, followed by a 12 week rest period, and an abomasal cannula was surgically implanted in all sheep. seven of the sensitized sheep were subsequently challenged with 50 000 h. contortus l3 while 4 control sheep were challenged with saline. biopsy samples were taken using a fibreoptic endoscope on days 0, 1, 2, 3, 5, 7 and 28 after challenge and leukocyte subpopulations quantified by (immuno)histology. differential blood cell c ... | 2010 | 20167198 |
| ovicidal and larvicidal activity of crude extracts of melia azedarach against haemonchus contortus (strongylida). | the rapid development of anthelmintic resistance, associated with the high cost of the available anthelmintic drugs, has limited the success of gastrointestinal nematodiosis control in sheep and goats and thus created interest in studying medicinal plants as an alternative source of anthelmintics. the aim of this study was carried out to evaluate the anthelmintic activity of the leaves and seed aqueous and hydro-alcoholic extracts of melia azedarach l. (meliaceae) were tested for in vitro ovicid ... | 2010 | 20177909 |
| an unc-49 gaba receptor subunit from the parasitic nematode haemonchus contortus is associated with enhanced gaba sensitivity in nematode heteromeric channels. | we have identified two genes from the parasitic nematode haemonchus contortus, hco-unc-49b and hco-unc-49c that encode two gaba-gated chloride channel subunits. electrophysiological analysis revealed that this channel has properties similar to those of the unc-49 channel from the free-living nematode caenorhabditis elegans. for example, the hco-unc-49b subunit forms a functional homomeric channel that responds to gaba and is highly sensitive to picrotoxin. hco-unc-49c alone does not respond to g ... | 2010 | 20180830 |
| the accuracy of the famacha-method in detecting anaemia and haemonchosis in goat flocks in switzerland under field conditions. | in this study, goats from six farms in central switzerland were examined for the evaluation of the famacha-method under middle european conditions. individual faecal egg counts were determined at a 4-week interval for a period of 6 months and the gastrointestinal nematode (gin) genera were differentiated using larval culture. simultaneously, the goats were bled for packed cell volume (pcv) determination and scored for anaemia of the conjunctiva according to the famacha-method. the three methods ... | 2010 | 20188478 |
| quarantine treatment of sheep with monepantel--rapidity of fecal egg count reduction. | in the presence of multiple anthelmintic resistance, effective quarantine treatment of sheep entering a farm has become a crucial tool in nematode management. in the present work, the use of the amino-acetonitrile derivative, monepantel as a quarantine treatment was investigated. of special interest was the rapidity of decrease in fecal egg counts (fec) compared to other anthelmintics used in sheep. in three different studies, sheep were either infected with haemonchus contortus of known resista ... | 2010 | 20207487 |
| monosaccharide composition of fundic and duodenal mucins in sheep infected with haemonchus contortus or teladorsagia circumcincta. | the effects on the monosaccharide composition of fundic and duodenal mucins of parasitism by haemonchus contortus or teladorsagia circumcincta were investigated in sheep at 4, 6 and 9 months of age. infected sheep were euthanased at days 21 and 28 post-infection respectively, together with uninfected controls. fundic and duodenal mucins were purified by gel filtration and cscl density gradient centrifugation and monosaccharides were released by heating at 95 degrees c for 6h in 2m hcl. thin-laye ... | 2010 | 20211529 |
| association of ion-channel genotype and macrocyclic lactone sensitivity traits in haemonchus contortus. | resistance to macrocyclic lactones in the strongylid parasite of sheep, haemonchus contortus, is associated with specific alleles of several genes, including those encoding ligand-gated chloride-channels. while previous functional studies of the ion-channels encoded by these resistant alleles have revealed alterations in ligand binding and response to the anthelmintics, we still do not know how these alleles are contributing to resistance in vivo. to understand the phenomenon of anthelmintic res ... | 2010 | 20211658 |
| cyclotide interactions with the nematode external surface. | cyclotides are a large family of cyclic cystine knot-containing plant peptides that have anthelminthic activities against haemonchus contortus and trichostrongylus colubriformis, two important gastrointestinal nematodes of sheep. in this study, we investigated the interaction of the prototypic cyclotide kalata b1 with the external surface of h. contortus larvae and adult worms. we show that cyclotides do not need to be ingested by the worms to exert their toxic effects but that an interaction wi ... | 2010 | 20211894 |
| haemonchus contortus: cloning and characterization of serpin. | the serpin gene of haemonchus contortus (hc-serpin) was cloned and characterized in this study. specific primers for rapid amplification cdna ends (race) were designed based on the expression sequence tag (est, bm173953) to amplify the 3'- and 5'-ends of hc-serpin. the full length of the cdna of this gene was obtained by overlapping the sequences of 3'- and 5'-extremities and amplification by reverse transcription-pcr. the biochemical activities of the recombinant protein (rhc-serpin), which was ... | 2010 | 20214897 |
| an ortholog of the ecdysone receptor protein (ecr) from the parasitic nematode haemonchus contortus. | high concentrations (> or =4.2mm) of 20e inhibit the development of haemonchus contortus eggs to the l3 larval stage. we report the cloning of cdna encoding an ecr ortholog (hcecr) from h. contortus mrna expressed during l3. phylogenetically, this and the putative ecr from brugia malayi form a separate branch between arthropod ecrs and liver x receptors. two isoforms of hcecr differ in the inclusion/omission of a 3-residue segment in the a/b domain. single nucleotide polymorphisms at 49 position ... | 2010 | 20226216 |
| maternal transference of passive humoral immunity to haemonchus contortus in goats. | this study evaluated the transference of maternal-specific antibodies against haemonchus contortus and the humoral immune response of 32 goat kids to natural infection by the parasite, from birth to 5 months of age. all serum samples collected immediately after birth and before colostrum ingestion were negative for h. contortus antibodies, as demonstrated by elisa. however, 30 and 60 days after colostrum and milk ingestion, antibody detection was positive and faecal egg count (fec) was negative, ... | 2010 | 20236709 |
| prevalence and distribution of gastrointestinal nematodes on 32 organic and conventional commercial sheep farms in ontario and quebec, canada (2006-2008). | in order to characterize the epidemiology of sheep gastrointestinal nematodes in organic and conventional flocks in canada, a longitudinal study was carried out from may 2006 to march 2008 on 32 purposively selected farms in ontario (on) and quebec (qc): 8 certified organic (co), 16 non-certified organic (nco), and 8 conventional (c) farms. on each farm, 10 ewes and 10 female lambs were selected. farm visits were undertaken monthly during the grazing season, and twice in the winter. at each visi ... | 2010 | 20236769 |
| efficacy of duddingtonia flagrans and arthrobotrys robusta in controlling sheep parasitic gastroenteritis. | the aim of this study was to evaluate the efficacy of formulations of sodium alginate matrix (pellets) of the nematode predatory fungi, duddingtonia flagrans (ac001 isolate) and arthrobotrys robusta (i-31 isolate), in the biological control of sheep gastrointestinal nematode infections. thirty young bergamacia ewes were allocated into three groups: in group 1 (control), the animals received 2 g/10 kg of live weight (l.w.) of pellets without fungus; in group 2, each animal received 2 g/10 kg of l ... | 2010 | 20237801 |
| 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 ... | 2010 | 21232867 |
| association between major histocompatibility complex microsatellites, fecal egg count, blood packed cell volume and blood eosinophilia in pelibuey sheep infected with haemonchus contortus. | the objective of this study was to assess the correlation among traits associated with resistance or susceptibility to haemonchus contortus infestation and to evaluate the participation of the ovine major histocompatibility complex (mhc) in pelibuey sheep, a prevalent breed in tropical and sub-tropical regions in mexico and elsewhere. association among the fecal egg count (fec), blood packed cell volume (pcv), antibody (ab) levels, serum proteins (sp) and blood eosinophil count (eos) was assesse ... | 2010 | 21208746 |
| in vitro effects of cassava (manihot esculenta) leaf extracts on four development stages of haemonchus contortus. | three extracts (aqueous, methanolic and dichloromethane) of manihot esculenta (cassava) leaf were tested in vitro on four development stages of haemonchus contortus using egg hatch assay (eha), larval development assay (lda), l3 migration inhibition assay (lmi) and adult worm motility assay (awm). compared to the negative control, significant effects (p<0.0001) were observed for the methanolic extract of leaf against larval development (57.6% +/-7.6), with a dose dependent effect. these results ... | 2010 | 20638799 |
| activity in vitro of fungal conidia of duddingtonia flagrans and monacrosporium thaumasium on haemonchus contortus infective larvae. | the objective of this work was to evaluate the predatory activity of the fungi duddingtonia flagrans (ac001) and monacrosporium thaumasium (nf34a) on haemonchus contortus infective larvae (l3) in two experimental assays (a and b). in assay a, two treatments and one control were formed and kept for 7 days in petri dishes with 2% water-agar. each treatment consisted of 1000 h. contortus l3 and 1000 conidia of only one fungal isolate, and the control group consisted of 1000 l3, without fungus, with ... | 2010 | 20663244 |
| monepantel allosterically activates deg-3/des-2 channels of the gastrointestinal nematode haemonchus contortus. | monepantel is the first drug of a new family of anthelmintics, the amino acetonitrile derivatives (aad), presently used to treat ruminants infected with gastrointestinal nematodes such as haemonchus contortus. monepantel shows an excellent tolerability in mammals and is active against multidrug-resistant parasites, indicating that its molecular target is absent or inaccessible in the host and is different from those of the classic anthelmintics. genetic approaches with mutant nematodes have sugg ... | 2010 | 20679419 |
| 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 ... | 2010 | 20684865 |
| 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- ... | 2010 | 21039613 |
| 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 ... | 2010 | 21055403 |
| 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 ... | 2010 | 21072409 |
| 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 ... | 2010 | 21075149 |
| 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 ... | 2010 | 21088894 |
| 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 ... | 2010 | 21103363 |
| 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 ... | 2010 | 21109354 |
| 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 ... | 2010 | 21156340 |
| 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 ... | 2010 | 21158637 |
| 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 ... | 2010 | 21161270 |