Publications

influence of dietary protein supply on resistance to experimental infections with haemonchus contortus in ile de france and santa ines lambs.	the effect of haemonchus contortus infection in sheep fed with a moderate and high protein content diet was evaluated in two breeds of sheep. forty-eight ile de france and santa ines lambs were maintained indoors since birth, in worm-free conditions. the lambs were allocated after weaning in four groups of six animals per breed, which were either infected or remain uninfected and given access to either a moderately or highly metabolizable protein diet. the moderately and highly metabolizable pro ...	2005	16098676
cells, cytokines and other molecules associated with rejection of gastrointestinal nematode parasites.	infections with gastrointestinal nematodes represent a major problem for human health and animal health and production. the physical size of the parasite, its changing life-cycle stages and the relative inaccessibility to host cells pose unique challenges to the immune system, which has evolved specialized strategies for parasite control. this paper reviews the work performed in the authors' laboratories to identify components that are involved in the natural rejection response against ruminant ...	2005	16099054
lack of effects of quebracho and sainfoin hay on incoming third-stage larvae of haemonchus contortus in goats.	the effects of tannins on adult populations of haemonchus contortus, trichostrongylus colubriformis and teladorsagia circumcincta in goats are characterised mainly by a decrease in egg excretion without any significant changes in worm number. in contrast, the impact of tannins on t. colubriformis or t. circumcincta third-stage larvae (l3) is associated with a significant reduction in worm establishment. the objective of the present study was to examine the effects of quebracho extract tannins on ...	2005	16129346
survey of nematophagous fungi in south africa.	three hundred and eighty-four samples of leaf litter, soil, faeces from domestic and game animals, compost and aqueous cultures of infective nematode larvae contaminated with unidentified fungi were plated out on water agar, baited with pure infective larvae of haemonchus contortus, incubated and examined for the presence of nematophagous fungi. duddingtonia flagrans was isolated from five samples, and 73 samples were positive for other nematophagous fungi.	2005	16137137
impact on productivity of peri-parturient rise in fecal egg counts in creole goats in the humid tropics.	the control of gastrointestinal nematodes requires an understanding of their epidemiology so that particular parasite stages can be targeted. dam infection during early lactation is one example of this in ruminant nematode infections. the existence of the peri-parturient relaxation in immunity and its impact on productivity were examined in a creole goat flock from guadeloupe, exposed to mixed natural infection (predominantly haemonchus contortus and trichostrongylus colubriformis). a total of 1 ...	2005	16165278
synthesis and anthelmintic properties of arylquinolines with activity against drug-resistant nematodes.	2,4-disubstituted quinolines with additional substituents in positions 5-8 have been found to have anthelmintic properties. a number of 2,4-dimethoxy-6- or 8-arylquinolines have potent activity against the sheep nematode haemonchus contortus, with ld99 values of the same order of magnitude as levamisole. these arylquinolines maintain their activity against levamisole-, ivermectin- and thiabendazole-resistant strains of h. contortus.	2005	16165359
effect of bioactive compounds from sainfoin ( onobrychis viciifolia scop.) on the in vitro larval migration of haemonchus contortus: role of tannins and flavonol glycosides.	anthelmintic bioactivity against gastrointestinal nematodes has been associated with leguminous forages supporting the hypothesis of a role of condensed tannins. however, the possibility that other compounds might also been involved has received less consideration. using bio-guided fractionation, the current study aimed at characterizing the biochemical nature of the active compounds present in sainfoin (onobrychis viciifolia ), previously identified as an anthelmintic leguminous forage. the eff ...	2005	16174418
haemonchus contortus: molecular cloning, sequencing, and expression analysis of the gene coding for the small subunit of ribonucleotide reductase.	gastro-intestinal (gi) parasites are of great agricultural importance, annually costing the livestock industry vast amounts in resources to control parasitism. one such gi parasite, haemonchus contortus, is principally pathogenic to sheep; with the parasite's blood-feeding behaviour causing effects ranging from mild anaemia to mortality in young animals. current means of control, which are dependent on repeated treatment with anthelmintic chemicals, have led to increasing drug resistance. togeth ...	2005	16183060
the ever-expanding neuropeptide gene families in the nematode caenorhabditis elegans.	neuropeptides act as chemical signals in the nervous system to modulate behaviour. with the ongoing est projects and dna sequence determination of different genomes, the identification of neuropeptide genes has been made easier. despite the relatively 'simple' repertoire of behaviours in the nematode caenorhabditis elegans, this worm contains a surprisingly large and diverse set of neuropeptide genes. at least 109 genes encoding over 250 potential neuropeptides have been identified in c. elegans ...	2005	16569285
resistance as a tool for discovering and understanding targets in parasite neuromusculature.	the problem of anthelmintic resistance prevents efficient control of parasites of livestock and may soon compromise human parasite control. research into the mechanisms of resistance and the quest for diagnostic tools to aid control has required research that focuses on field resistance. on the other hand, resistant worms, including those kept in the laboratory, provide useful tools for studying drug action, especially at neuromuscular targets in worms. while the needs and directions of these re ...	2005	16569289
haemonchus contortus egg excretion and female length reduction in sheep previously infected with oestrus ovis (diptera: oestridae) larvae.	mixed parasitic infection of animals is a common phenomenon in nature. the existence of one species often positively or negatively influences the survival of the other. our experimental study was started with the objectives to demonstrate the interaction of haemonchus contortus and oestrus ovis in relation to cellular and humoral immune responses in sheep. twenty-two sheep of tarasconnais breed (france) were divided into four groups (o, oh, h and c) of five or six animals. group o and oh receive ...	2005	15740864
multiple anthelmintic resistance in haemonchus contortus isolated from south african boer goats in switzerland.	a suspected case of multiple anthelmintic resistance on a farm in the canton of zurich, switzerland, into which south african boer goats had previously been imported, was confirmed in a controlled test. twenty sheep were allocated into one control group and three treatment groups to determine the efficacy of mebendazole, ivermectin and moxidectin applying the faecal egg count reduction test (fecrt). the sheep were slaughtered 1 week later and post-mortem worm counts were performed. benzimidazole ...	2005	15740865
effect of ivermectin on feeding by haemonchus contortus in vivo.	while several in vitro studies have shown that the anthelmintic ivermectin inhibits feeding by parasites, the relevance of this putative site of action in vivo has not been demonstrated. for this study, techniques to measure feeding by haemonchus contortus in vivo relied on the blood feeding characteristics of the worm, and utilised tritiated inulin administered to sheep intravenously and subsequently measured in worms recovered from abomasa. nematodes recovered from sheep treated with ivermecti ...	2005	15740872
in vivo effects of fagara leaves on sheep infected with gastrointestinal nematodes.	infections of the gastrointestinal tract with parasitic nematodes, and particularly haemonchus contortus, represent one of the main pathological constraints on the breeding of small ruminants in tropical countries. owing to the constant development of anthelmintic resistance in worm populations, alternative control methods are being evaluated, including an assessment of the value of the traditional plants. the effect of the consumption of fagara leaves on sheep infected with gastrointestinal nem ...	2005	15747857
investigations on the seasonal patterns of strongyle infections in grazing lambs, and the occurrence of anthelmintic resistance on sheep and goat farms in western anatolia, turkey.	the seasonal patterns of strongyle infections in untreated, weaned lambs were determined on four governmental farms during a grazing season. in three farms, the infection level (predominantly teladorsagia spp. and trichostrongylus spp.) measured by egg counts or worm burdens remained low throughout the study; higher egg counts mainly caused by haemonchus contortus were transiently recorded on the fourth farm. significant body weight gains were observed in all groups, but they varied between farm ...	2005	15765247
isolation and characterisation of a beta tubulin isotype 2 gene from two species of cyathostomin.	this study describes the isolation and characterisation of beta tubulin isotype 2 cdna sequences from two common species of cyathostomin, cylicocyclus nassatus and cyathostomum catinatum. the full-length cdnas for these species were 1709 and 1753 bp in length, respectively, including 1350 bp of sequence inferred to encode 450 amino acids of peptide sequence. they had greatest identity with previously characterised isotype 2 sequences from trichostrongylus colubriformis, cooperia oncophora and ha ...	2005	15777911
efficacy of two cyclooctadepsipeptides, pf1022a and emodepside, against anthelmintic-resistant nematodes in sheep and cattle.	resistance against the major currently available anthelmintics has reached a critical level in many small ruminant herds world-wide, and is increasingly becoming a problem in horses and cattle. therefore, new products with different modes of action are urgently needed. recently, such a new class of compounds, the anthelmintically active cyclooctadepsipeptides, was described. here, the effects of cyclooctadepsipeptides on benzimidazole-, levamisole- and ivermectin-resistant populations of haemonc ...	2005	15796017
presence of the ldnf glycan on the host-protective h-gal-gp fraction from haemonchus contortus.	immunization of sheep with the gut membrane-associated protein complex h-gal-gp of adult haemonchus contortus induces high levels of protection against a homologous challenge infection. protection is correlated with a systemic igg response against the antigen. analysis of the antibody response showed that the majority of the antigen-specific igg was of the igg2 isotype. a substantial proportion (74%) of this response was directed against the glycan component of h-gal-gp. the high immunogenicity ...	2005	15813723
the possibilities and limitations of evasive grazing as a control measure for parasitic gastroenteritis in small ruminants in temperate climates.	between 1999 and 2003 studies were done at utrecht university on the population dynamics of gastrointestinal nematodes and the potential to use evasive grazing for the control of nematode infections in small ruminants. on most pastures grazed in may and june it took at least 3 weeks before high pasture infectivity levels for haemonchus contortus developed while it took at least 2 weeks on pastures grazed in july, august and september. occasionally, larvae emerged earlier on pasture when high tem ...	2005	15817209
characterisation of the two most abundant genes in the haemonchus contortus expressed sequence tag dataset.	analysis of the haemonchus contortus expressed sequence tag (est) dataset revealed that almost 10% of all ests (1719 ests) belong to a family of related genes. close analysis of the ests suggests that these represent two genes (called here hc-nim-1 and hc-nim-2) with multiple alleles of each. these genes show significant similarity to two genes from caenorhabditis elegans, f54d5.3 (wormbase accession wbgene00010049, corresponding protein wp:ce28033) and f54d5.4 (wbgene00010050, wp:ce03409) of un ...	2005	15826643
persistent efficacy of doramectin against haemonchus contortus in goats.		2005	15828727
molecular and biochemical characterization of a protein cyclophilin from the nematode haemonchus contortus( p ).	we have cloned, sequenced and expressed a gene of haemonchus contortus that encodes a protein (termed hccyp) consisting of a cyclophilin domain and an rna recognition motif (rrm). an antiserum raised against the recombinant protein showed that hccyp was present in the insoluble fraction (mostly nuclear) of the parasite homogenate. the recombinant protein possessed the typical cis-trans peptidyl-prolyl isomerase activity of cyclophilins and this activity was inhibited by the immunosuppressant cyc ...	2005	15830208
characterization of proteinases in different isolates of adult haemonchus contortus.	a high degree of intra- and inter-geographical variation has been demonstrated previously in the excretory/secretory proteinases released by adult haemonchus contortus. proteinase activity has also been associated with host-protective 'hidden' antigens isolated from the gut of adult h. contortus. if similar geographical strain variation also exists within the gut-associated proteinases, this will have important implications for the development of a globally effective vaccine. the proteinases act ...	2005	15830817
synthesis and anthelmintic activity of 7-substituted 3,4a-dimethyl-4a,5a,8a,8b-tetrahydro-6h-pyrrolo[3',4':4,5]furo[3,2-b]pyridine-6,8(7h)-diones.	the racemic 7-substituted 3,4a-dimethyl-4a,5a,8a,8b-tetrahydro-6h-pyrrolo[3',4':4,5]furo[3,2-b]pyridine-6,8(7h)-diones represent novel tricyclic compounds with strong in vivo efficacy against the parasitic nematode haemonchus contortus rudolphi in sheep. here we report on the synthesis of tricyclic endo-2,3-dihydro[3,2-b]pyridine-type cycloadducts and describe the separation of the racemic 3,4a-dimethyl-7-ethyl-4a,5a,8a,8b-tetrahydro-6h-pyrrolo[3',4':4,5]furo[3,2]pyridine-6,8(7h)-dione into the ...	2005	15837328
real time pcr for the diagnosis of benzimidazole resistance in trichostrongylids of sheep.	this report describes a new molecular method for the diagnosis of benzimidazole susceptibility or resistance in three main species of trichostrongylids of sheep (haemonchus contortus, teladorsagia circumcincta and trichostrongylus vitrinus). this assay is based on the use of real time polymerase chain reaction (pcr) to detect mutations of residue 200 on isotype 1 of beta-tubulin. the technique allows calculation of the proportion of each allelic variant as it combines kinetic (real time quantita ...	2005	15845285
rapid selection for ivermectin resistance in haemonchus contortus.	lambs infected with two isolates, one british and one american, of haemonchus contortus were treated with increasing doses of ivermectin. eggs from the highest dose that had not eliminated the infection were cultured and larvae used to infect another lamb. after three generations the h. contortus was resistant to 0.2 mg/kg ivermectin. the results stress the ease with which ivermectin resistance can be selected if high selection pressure is applied.	2005	15845291
increased resistance to anthelmintics of haemonchus contortus eggs associated with changes in membrane fluidity of eggshells during embryonation.	the embryonation of nematode eggs has been shown to increase their resistance to anthelmintics when parasites are submitted to egg hatch assays. nevertheless, no mechanism has been suggested to explain this phenomenon. earlier observations by other authors showed that the biochemical composition of eggshells is altered during the embryonation of eggs. the functional consequences of these changes have not been identified. we studied the changes in membrane environment (eggshells) of haemonchus co ...	2005	15678352
in vitro effects of four tropical plants on three life-cycle stages of the parasitic nematode, haemonchus contortus.	alcoholic extracts of four tropical plants (zanthoxylum zanthoxyloides, newbouldia laevis, morinda lucida and carica papaya) were screened in vitro for potential anti-parasitic effects against eggs, infective larvae and adult haemonchus contortus. significant effects were obtained with all four plants but differences were observed depending on the parasitic stage. the effects of the four plant extracts were similar on egg hatching and were dose dependent. in contrast, no dose-response relationsh ...	2005	15563923
haemonchus contortus: parasite problem no. 1 from tropics - polar circle. problems and prospects for control based on epidemiology.	there is no doubt that on a global basis, haemonchus contortus is by far the most important parasite of small ruminants (sheep and goats). this is particularly more so now, with the development of high levels of resistance to both the broad and narrow spectrum anthelmintic drugs in h. contortus throughout the world. epidemiological studies describe the lower environmental limits for haemonchosis to occur in sheep, as being a mean monthly temperature of 18c and approximately 50mm rainfall. thus i ...	2005	16883278
influence of the cyclooctadepsipeptides pf1022a and pf1022e as natural products on the design of semi-synthetic anthelmintics such as emodepside.	the 24-membered cyclooctadepsipeptide (codp) pf1022a, the active metabolite of the fungus imperfectus mycelia sterilia (rosellinia sp.) isolated from the plant camellia japonica in japan, is described as a powerful broad-spectrum anthelmintic natural product with low toxicity in animals. further codps such as pf1022b, c, d and e have been isolated from the same culture and their structures have been established. both pf1022a and pf1022e serve as valuable starting materials for the synthesis of s ...	2005	16228266
cyclohexadepsipeptides (chdps) with improved anthelmintical efficacy against the gastrointestinal nematode (haemonchus contortus) in sheep.	besides 24-membered cyclooctadepsipeptides (codps) with the most prominent member of this class emodepside, the structurally related 18-membered cyclohexadepsipeptides (chdps) were of interest with regard to their efficacy against the nematode h. contortus in sheep.the chdps prepared by a simple total synthesis represent enniatin derivatives with strong in vivo activity against h. contortus in sheep. the correlation between the nature of the chdp major conformers and their anthelmintic activitie ...	2005	16228271
putative g protein-coupled receptors in parasitic nematodes--potential targets for the new anthelmintic class cyclooctadepsipeptides?	parasitic nematodes cause major problems in livestock animals. resistances to the most commonly used drugs are arising. the cyclooctadepsipeptide emodepside belongs to a new class of anthelmintics. a receptor for emodepside, hc110-r, was previously identified in haemonchus contortus. we have identified the complete coding sequences of putative orthologues in cooperia oncophora and ostertagia ostertagi, tri-chostrongyles in cattle. the putative receptors were named depsiphilins. the deduced amino ...	2005	16228272
the nematode-trapping efficacy of two chlamydospore-forming fungi against haemonchus contortus in sheep.	an in vitro study was carried out to determine efficacy of indian isolates of the nematode-trapping fungi arthrobotrys musiformis and duddingtonia flagrans to capture infective larvae of haemonchus contortus. these fungi have previously been screened and selected for their survival in the gastrointestinal tract of sheep without losing growth and nematode capturing potential. following the feeding of chlamydospores of these two fungi alone or in combination in sheep experimentally infected with h ...	2005	16336714
the development and overwintering survival of free-living larvae of haemonchus contortus in sweden.	five complimentary studies were undertaken with the overall aim to examine the ability of free-living stages of haemonchus contortus to over-winter and tolerate cold stress. two studies deal with the development and long-term survival of eggs and infective larvae of two geographically different isolates (kenya and sweden). eggs and larvae were monitored in climatic chambers at temperatures that fluctuated daily between -1 degrees c and 15 degrees c, or at constant temperatures of 5 degrees c and ...	2005	16336722
[the occurrence of intestinal parasites of roe deer and red deer in the western pomerania voivodeship].	the aim of the study was to establish the parasite prevalence of roe deer and red deer in western pomerania.	2005	16913504
helminths in sympatric populations of mountain reedbuck (redunca fulvorufula) and gray rhebok (pelea capreolus) in south africa.	helminths of mountain reedbuck (redunca fulvorufula fulvorufula) and gray rhebok (pelea capreolus) were investigated in south africa between june 1999 and february 2002. forty-one mountain reedbuck were culled at sterkfontein dam nature reserve over 8 different periods, and 25 mountain reedbuck were culled at tussen die riviere nature reserve over 3 different periods. a total of 17 kinds of helminths were found at the 2 sites, including 15 nematodes, 1 trematode, and 1 cestode. at sterkfontein, ...	2005	17089756
gastrointestinal nematodes of small ruminants: life cycle, anthelmintics, and diagnosis.	strongylid gastrointestinal nematodes are an important cause of disease and economic loss in small ruminants. these parasites are particularly important in the eastern united states where the bloodsucking parasite haemonchus contortus is the predominant species. sheep and goats are infected with gastrointestinal nematodes while grazing and the biology of the infective larvae on the pastures is important in planning effective control programs. fecal egg counts can be used to monitor control progr ...	2006	17071351
effect of sainfoin (onobrychis viciifolia) silage and hay on established populations of haemonchus contortus and cooperia curticei in lambs.	the objective of the study was to examine the effect of dried and ensiled sainfoin (onobrychis viciifolia) on established populations of haemonchus contortus (abomasum) and cooperia curticei (small intestine) in lambs under controlled conditions. twenty-four parasite naïve lambs were inoculated with a single dose of infective larvae of these parasites 28 days prior to the start of the feeding experiment. twenty-four days post-infection, 4 days prior to the start of the feeding experiment, animal ...	2006	16934938
global patterns reveal strong population structure in haemonchus contortus, a nematode parasite of domesticated ruminants.	we have examined the global population genetic structure of haemonchus contortus. the genetic variability was studied using both amplified fragment length polymorphism (aflp) and nad4 sequences of the mitochondrial genome. to examine the performance and information content of the two different marker systems, comparative assessment of population genetic diversity was undertaken in 19 isolates of h. contortus, a parasitic nematode of small ruminants. a total of 150 individual adult worms represen ...	2006	16950266
rnai in haemonchus contortus: a potential method for target validation.	rna interference (rnai) is a method for the functional analysis of specific genes, and is particularly well developed in the free-living nematode caenorhabditis elegans. there have been several attempts to apply this method to parasitic nematodes. in a recent study undertaken in haemonchus contortus, geldhof and colleagues concluded that, although a mechanism for rnai existed, the methods developed for rnai in c. elegans had variable efficacy in this parasitic nematode. the potential benefits of ...	2006	16971180
endomesoderm specification in caenorhabditis elegans and other nematodes.	the endomesoderm gene regulatory network (grn) of c. elegans is a rich resource for studying the properties of cell-fate-specification pathways. this grn contains both cell-autonomous and cell non-autonomous mechanisms, includes network motifs found in other grns, and ties maternal factors to terminal differentiation genes through a regulatory cascade. in most cases, upstream regulators and their direct downstream targets are known. with the availability of resources to study close and distant r ...	2006	16998834
[experiences with the famacha-eye-colour-chart for identifying sheep and goats for targeted anthelmintic treatment].	the bloodsuckling abomasal parasite haemonchus contortus is the most pathogenic worm in sheep and goats. high prevalences of anthelmintic-resistant isolates make h. contortus difficult to control. detecting the most anaemic animals could support a targeted selective treatment approach. leaving the rest of the flock untreated would generate a refuge for anthelmintic-sensitive parasites. south-african researchers tried the famacha-eye-colour-chart for anaemic sheep and goats with good success. fie ...	2006	17007472
ivermectin selection on beta-tubulin: evidence in onchocerca volvulus and haemonchus contortus.	ivermectin resistance is common in trichostrongylid nematodes of livestock, such as haemonchus contortus. this anthelmintic is the only drug approved for mass administration to control onchocerciasis caused by the nematode parasite, onchocerca volvulus. in parts of west africa up to 18 rounds of ivermectin treatment have been administered to communities and there are reports of poor parasitological responses to treatment. understanding ivermectin resistance and ivermectin selection is an importa ...	2006	17007942
feasibility of genus-specific real-time pcr for the differentiation of larvae from gastrointestinal nematodes of naturally infected sheep.	results of real-time pcr analysis of coproculture third stage larvae (l3) using genus specific taqman minor groove binder probes were compared with the results of morphological differentiation of l3 after coprocultured and direct morphological worm differentiation from gastrointestinal samples of eight sheep with naturally acquired nematodes infections. faecal egg counts prior to postmortem confirmed infections with trichostrongyles with a geometric mean count of 4828 eggs per gram for all sheep ...	2006	17009713
ecology of the free-living stages of major trichostrongylid parasites of sheep.	significant developments over recent decades make it timely to review the ecology of the major gastrointestinal nematode (gin) species of sheep. these include the relentless development and spread of anthelmintic resistance in all of the major sheep production regions of the world, and the consequent drive towards integrated parasite management (ipm) systems incorporating non-chemotherapeutic strategies such as grazing management. the success of such programs is dependent on a detailed understan ...	2006	17011129
[a new control method for haemonchus contortus: famacha].	famacha is a method that has been developed against haemonchus contortus which causes anemia in sheep and goats especially in tropical and subtropical areas. the basic principle of the method is the detection of the color changes in the mucous membrane of the eye that is caused by anemia. according to the famacha anemia guide, (fag), the mucous membranes of the eyes of animals are inspected for color differences at two or three week intervals. the criteria are used for treating the animals. thus ...	2006	17106855
evaluation of broad-spectrum anthelmintic activity in a novel assay against haemonchus contortus, trichostrongylus colubriformis and t. sigmodontis in the gerbil meriones unguiculatus.	the gerbil meriones unguiculatus, infected with three species of nematodes, each located in a separate part of the gastrointestinal tract, provided a reliable laboratory assay for the evaluation of broad-spectrum anthelmintic activity. gerbils harbouring 6-day-old infections of haemonchus contortus, trichostrongylus colubriformis and t. sigmodontis were given selected broad-spectrum anthelmintics by gavage. three benzimidazoles, thiabendazole, oxfendazole and albendazole, a tetrahydropyrimidine, ...	2006	17125549
use of bacillus thuringiensis toxin as an alternative method of control against haemonchus contortus.	the biocide activity of bacillus thuringiensis (b. thuringiensis) ib-16 strain was evaluated against the blood-feeding nematode haemonchus contortus (h. contortus) in vitro and in vivo assays. twenty experimental jirds (meriones unguiculatus) and 32 sheep were infected with h. contortus by oral route. fourteen days post infection 10 jirds were treated with 0.2 mg per ml of ib-16 soluble toxin by intraperitoneal (i.p.) route and 8 sheep were treated with 0.5 mg of toxin per kg of body weight by i ...	2006	17135537
selective and on-demand drenching of lambs: impact on parasite populations and performance of lambs.	to determine whether drenching regimes for lambs by which a proportion (10%) of the heaviest animals was selectively left untreated, or animals are only drenched 'on demand' when faecal nematode egg counts (fec) exceeded a threshold level, would result in measurable increases in parasite larval challenge in the autumn and/or decreases in the performance of lambs.	2006	17151729
abomasal nematode community in an alpine chamois (rupicapra r. rupicapra) population before and after a die-off.	abomasa of 185 chamois shot during 5 consecutive hunting seasons were collected as part of a health monitoring program in an alpine area of italy and examined for nematodes. the data were obtained during both the preceding period and that following a severe die-off caused by a pneumonia outbreak. prevalence, mean abundance, mean intensity, and thul importance index were consistently high, in particular for haemonchus contortus, having a low host specificity and high pathogenic potential. species ...	2006	17152929
anhydrobiosis increases survival of trichostrongyle nematodes.	this study demonstrates that infective-stage larvae of 2 trichostrongyle ruminant gastrointestinal nematodes, haemonchus contortus and trichostrongylus colubriformis, can enter into anhydrobiotic states when completely desiccated. larvae of control trichostrongyle species, heligmosomoides polygyrus and nippostrongylus brasiliensis, that infect mice were unable to survive desiccation or to enter into anhydrobiosis. ruminant larvae were able to survive up to 7 desiccation/rehydration cycles, and, ...	2006	17152941
rapid improvement of immunity to teladorsagia circumcincta is achieved through a reduction in the demand for protein in lactating ewes.	protein supplementation can improve the resistance to parasites of periparturient ewes, as indicated by reduced nematode egg excretion and worm burdens. however, the rate at which this improvement can occur is largely unknown. we investigated the rate of improvement by assessing temporal changes in faecal egg counts after we experimentally reduced nutrient demand. three groups of nine pregnant ewes each were trickle infected with teladorsagia circumcincta from day(-70) to day(16) (parturition is ...	2006	16337633
cloning and characterization of the cu/zn superoxide dismutase of trichinella pseudospiralis.	copper/zinc (cu/zn) superoxide dismutase (sod) activity was identified for the first time in both crude somatic extracts (ce) and excretory/secretory (e/s) products of trichinella pseudospiralis. it was the dominant sod in infective-stage larvae. native polyacrylamide gel electrophoresis of ce and e/s products yielded a prominent band, which was cyanide-sensitive and was partly inhibited by hydrogen peroxide in sod assay. cytosolic cu/zn sod was cloned. the 471-bp full-length cdna sequence conta ...	2006	16341881
an immunogenic cathepsin f secreted by the parasitic stages of teladorsagia circumcincta.	teladorsagia circumcincta is a common, pathogenic abomasal nematode of sheep. in order to improve disease control in parasite isolates resistant to several anthelmintics, alternative methods must be sought. sheep develop acquired immunity to t. circumcincta so vaccination is a valid option for control. for this reason, we are investigating parasite excretory/secretory products for molecules, which have potential to invoke protective immunity against t. circumcincta. here, we describe experiments ...	2006	16387304
effects of four tanniferous plant extracts on the in vitro exsheathment of third-stage larvae of parasitic nematodes.	the anthelmintic properties of tanniferous plants and of their secondary metabolites represent one possible alternative to chemotherapy that is currently being explored as a means of achieving sustainable control of gastrointestinal nematodes in ruminants. previous in vivo and in vitro results suggest that tanniferous plants can have direct anti-parasitic effect against different stages of nematodes. however, the mode of action of the bioactive plant compounds remains obscure. the objectives of ...	2006	16388690
in vitro and in vivo anthelmintic activity of nicotiana tabacum l. leaves against gastrointestinal nematodes of sheep.	the in vitro and in vivo anthelmintic activity of nicotiana tabacum l. leaves was studied to rationalize its traditional use. live haemonchus contortus were used to assess the in vitro anthelmintic effect of a crude aqueous extract (cae) and a methanol extract (cme) of n. tabacum. the in vitro inhibitory effect of both the extracts was evident from the paralysis and/or mortality of worms noted at 6 h post-exposure. for the in vivo studies, cae and cme were administered in increasing doses (1.0-3 ...	2006	16397920
towards the eradication of haemonchus contortus from sheep flocks in sweden.	previous studies have shown that between-year transmission of haemonchus contortus in swedish sheep flocks is almost entirely as over-wintered populations within housed animals, and not on pasture. this suggests that eradication of this parasite is a realistic possibility. thus, two sheep farms with a history of h. contortus infection on the swedish island of oland were selected for study. during the winter housing period of 2003/2004 all ruminants (sheep and cattle) on both farms were treated w ...	2006	16406331
eosinophil interactions with haemonchus contortus larvae in the ovine gastrointestinal tract.	sheep were immunized by weekly oral infections with haemonchus contortus for 9 weeks followed by anthelmintic treatment. they were challenged either 9 or 22 weeks later with pbs (sham controls) or one million exsheathed l3 surgically injected in the abomasum, and killed 24 h or 48 h later. sheep challenged 9 weeks after immunization displayed varying degrees of tissue eosinophilia that showed a significant inverse relationship with the number of intra-epithelial mast cells (globule leucocytes). ...	2006	16441509
testing the efficacy of rna interference in haemonchus contortus.	rna interference (rnai) is widely used in caenorhabditis elegans to identify gene function and has been adapted as a high throughput screening method to identify genes involved in essential processes. we have been examining whether rnai could also be used on the strongylid parasitic nematode haemonchus contortus to study gene function. eleven genes were targeted in l1 and exsheathed l3 h. contortus larvae with rnai methodologies which have been shown to be effective in c. elegans and parasitic n ...	2006	16469321
a modified larval migration assay for detection of resistance to macrocyclic lactones in haemonchus contortus, and drug screening with trichostrongylidae parasites.	we have developed a modified migration assay system in 96-well plate format which is able to detect resistance to the macrocyclic lactone group of drugs in haemonchus contortus. the assay involves exposure of infective stage larvae to drug for a 24 h period, then counting the numbers of larvae that are able to migrate through an agar and filter mesh system over a further 48 h. the agar barrier greatly increased the sensitivity of the assay for resistance detection compared to use of filter mesh ...	2006	16472922
rna interference in haemonchus contortus: suppression of beta-tubulin gene expression in l3, l4 and adult worms in vitro.	we have used rnai to target two beta-tubulin genes in the parasitic stages of haemonchus contortus in vitro. soaking exsheathed-l3, l4 and adult worms in medium containing dsrna resulted in a significant decrease (greater than 1000-fold in some cases) in the expression of the specific beta-tubulin transcript, as measured by quantitative pcr. during the initial 24h exposure to the dsrna, the gene suppression effect was quite specific to the targeted gene. six days after initial exposure to dsrna, ...	2006	16253354
haemonchus contortus and trichostrongylus colubriformis in pen-trials with javanese thin tail sheep and kacang cross etawah goats.	weight gain costs due to infection were higher in sheep than goats, 28 and 17.5%, respectively, for trichostrongylus colubriformis and 48.7 and 32.2%, respectively, for haemonchus contortus. the extent of bodyweight cost attributed to anorexia in sheep infected with h. contortus was higher (13.5 g/day) than in sheep infected with t. colubriformis (2.3 g/day). on the other hand, bodyweight cost due to the other pathogenic effects in sheep infected with t. colubriformis were higher (35.6 g/day) co ...	2006	16310309
synergism of rotenone by piperonyl butoxide in haemonchus contortus and trichostrongylus colubriformis in vitro: potential for drug-synergism through inhibition of nematode oxidative detoxification pathways.	the anthelmintic properties of rotenone and its activity in combination with the cytochrome p450 inhibitor piperonyl butoxide, were examined in in vitro assays with adults and larvae of haemonchus contortus and larvae of trichostrongylus colubriformis. rotenone was toxic to larvae of both species, with lc(50) values in larval development assays of 0.54 and 0.64 microg/ml for h. contortus and t. colubriformis, respectively. the compound also caused complete cessation of movement in adult h. conto ...	2006	16325340
comparative efficacy of the nematode-trapping fungus duddingtonia flagrans against haemonchus contortus, teladorsagia circumcincta and trichostrongylus colubriformis in goat faeces: influence of the duration and of the temperature of coproculture.	amongst the alternative strategies to the use of anthelmintics, the administration of duddingtonia flagrans spores has already proved its efficacy in reducing the number of developing larvae of several nematode species in goat faeces. in this trial, the efficacy of this fungus against the larvae of the three major nematode species of goats was compared in various conditions of coproculture. twelve strongyle free goats were experimentally infected with either trichostrongylus colubriformis, telad ...	2006	16328368
phenotypic characterization of haemonchus contortus: a study of isolates from sweden and kenya in experimentally infected sheep.	the effects of cold storage of infective third-stage larvae (l3) of different isolates of the parasitic nematode haemonchus contortus were studied with respect to infectivity, pre-patent period and propensity for larval arrestment. two complementary experiments were conducted with 2 groups of lambs, each animal being inoculated with 2000 l3 of either swedish or kenyan origin. in a first experiment, l3s were cold treated at 5 degrees c for 9 months prior to infection, whereas in a second experime ...	2006	16332287
isolation and insecticidal/anthelmintic activity of xanthonol, a novel bis-xanthone, from a non-sporulating fungal species.	xanthonol, a novel dimeric xanthone, was isolated from a fermentation broth of a non-sporulating fungal species using sephadex lh20 followed by hplc and the structure elucidated by spectral analysis. xanthonol exhibited insecticidal and anthelmintic activities against larvae of lucilia sericata, aedes aegypti, and haemonchus contortus with ld90 of 33, 8, and 50 microg/ml, respectively.	2006	16883778
understanding anthelmintic resistance: the need for genomics and genetics.	anthelmintic resistance is a major problem for the control of many parasitic nematode species and has become a major constraint to livestock production in many parts of the world. in spite of its increasing importance, there is still a poor understanding of the molecular and genetic basis of resistance. it is unclear which mutations contribute most to the resistance phenotype and how resistance alleles arise, are selected and spread in parasite populations. the main strategy used to identify mut ...	2006	16889782
identification of secreted cysteine proteases from the parasitic nematode haemonchus contortus detected by biotinylated inhibitors.	seven cathepsin b-like cysteine proteases (cbls) were identified from the immunoprotective excretory-secretory products of haemonchus contortus. two-dimensional (2-d) zymography and biotinylated inhibitors were employed to localize active cbls in 2-d protein gels. mass spectrometry provided the identification of ac-4, hmcp1, hmcp2, and gcp7 as well as three novel cbls encoded by clustered expressed sequence tags.	2006	16495580
haemonchus contortus: prokaryotic expression and enzyme activity of recombinant hcstk, a serine/threonine protein kinase.	members of the par-1/mark serine/threonine protein kinase (stk) subfamily are important regulators of the cytoskeleton, and their characterization can provide insights into a number of critical processes relating to the development and survival of an organism. we previously investigated the mrna expression for and organization of a gene (hcstk) representing hcstk, an stk from the parasitic nematode haemonchus contortus. in the present study, a recombinant form of hcstk was expressed and characte ...	2006	16500645
effects of legume forages on ovine gastrointestinal parasite development, migration and survival.	lambs grazing certain legumes have reduced parasite intensities compared to lambs grazing ryegrass swards. eighteen replicates of white clover (cv. aberherald), lucerne (cv. luzelle), red clover (cv. merviot) and perennial ryegrass (cv. abersilo) were sown at equivalent field rates in 25 cm diameter pvc pots and maintained outside for 6 months. on day 0, forage in each pot was cut to 50 mm from soil level and the pots were placed in a glasshouse (at 19-25 degrees c and 70% humidity) in a randomi ...	2006	16516388
effect of cd4+ t lymphocyte depletion on resistance of gulf coast native lambs to haemonchus contortus infection.	it has been reported that cd4(+) t lymphocytes are important in acquired immunity to gastrointestinal nematode infection. whether these lymphocytes are also involved in the immune response of naturally resistant gulf coast native (gcn) sheep to haemonchus contortus infection remains to be defined. the objective of this study was to determine the role of cd4(+) t lymphocytes in this resistance. ten gcn lambs were randomly assigned to a control (n=5) or a treatment (n=5) group. the treatment consi ...	2006	16516389
identification of a 66 kda haemonchus contortus excretory/secretory antigen that inhibits host monocytes.	a 66 kda adult haemonchus contortus excretory/secretory (e/s) antigen was identified in western blot by reaction with sera from the infected goats. the protein was purified from the adult worm extract and e/s products by anion exchange and cona-sepharose chromatography. the purified protein inhibited monocyte function in vitro as judged by decreased production of hydrogen peroxide and nitric oxide in the culture medium. the protein also caused proliferation of peripheral blood mononuclear cells. ...	2006	16517075
caenorhabditis elegans ivermectin receptors regulate locomotor behaviour and are functional orthologues of haemonchus contortus receptors.	the target site for the anthelmintic action of ivermectin is a family of nematode glutamate-gated chloride channel alpha subunits (gluclalpha) that bind the drug with high affinity and mediate its potent paralytic action. whilst the action of ivermectin on the pharyngeal muscle of nematodes is relatively well understood, its effect on locomotor activity is less clear. here we use rnai and gene knockouts to show that four gluclalpha subunits are involved in regulating the pattern of locomotor act ...	2006	16527366
isolation and characterization of class ii myosin genes from haemonchus contortus.	in this study, cdnas encoding myosin from the parasitic nematode haemonchus contortus were isolated and characterized. several exhibited a considerable degree of sequence variation at the nucleotide and limited divergence at the amino acid levels within the various functional domains. the results suggest that the cdnas isolated represented a single myosin heavy chain, which, by comparison with a number of other myosins, is inferred to represent a homologue of a muscle myosin (cemhca) of the free ...	2006	16547732
control of gastrointestinal nematodes in goats on pastures in south africa using nematophagous fungi duddingtonia flagrans and selective anthelmintic treatments.	the effectiveness of selective anthelmintic treatments and use of nematophagous fungi duddingtonia flagrans in reducing levels of gastrointestinal nematodes in goats was investigated at onderstepoort, south africa. nineteen (19) naturally infected indigenous male goats, aged 10 months, were separated into four groups and grazed in separate previously ungrazed paddocks for two worm seasons (february 2002-march 2003). two groups of goats were fed d. flagrans chlamydospores daily and two groups did ...	2006	16563632
sericea lespedeza hay as a natural deworming agent against gastrointestinal nematode infection in goats.	infection with gastrointestinal nematodes (gin), particularly haemonchus contortus, is the biggest constraint to profitable goat production in the united states (us). due to widespread prevalence of anthelmintic resistance in goat gin, alternative, non-chemical control methodologies are needed to increase profitability of small ruminant industries. a study was designed to test the efficacy of a high condensed tannin (ct) legume, sericea lespedeza [sl, lespedeza cuneata (dum.-cours. g. don)] agai ...	2006	16564132
detection of benzimidazole resistance in haemonchus contortus using rflp-pcr technique.	benzimidazole (bz) resistance in haemonchus contortus is linked primarily with the mutation in the beta-tubulin isotype 1 gene that substitute phenylalanine (phe) to tyrosine (tyr) at 200 codon of the gene. in the present study, a new restriction fragment length polymorphism-polymerase chain reaction (rflp-pcr) technique has been developed for detection of bz resistance in the beta-tubulin isotype 1 gene of h. contortus. the technique utilizes two primers viz. avikaf and avikar to amplify the re ...	2006	16567043
vaccines against blood-feeding nematodes of humans and livestock.	this paper summarises the progress towards vaccine development against the major blood-feeding nematodes of man and livestock, the hookworms and haemonchus contortus, respectively. the impact of the diseases and the drivers for vaccine development are summarized as well as the anticipated impact of the host immune response on vaccine design. the performance requirements are discussed and progress towards these objectives using defined larval and adult antigens, many of these being shared between ...	2006	17274849
helminth parasites of gemsbok (oryx gazella) in the klein karoo.	the number and species of helminth parasites from three gemsbok (oryx gazella) were recorded, and their faecal nematode egg counts and the level of pasture contamination determined. six nematode genera were recovered and four species identified, of which trichostrongylus rugatus was the most prevalent. other nematode species recovered were cooperia sp., agriostomum sp., haemonchus contortus, nematodirus spathiger and ostertagia ostertagi. none of the worms were present in all animals studied, an ...	2006	17283732
evaluation of multiple low doses of copper oxide wire particles compared with levamisole for control of haemonchus contortus in lambs.	high levels of anthelmintic resistance in gastrointestinal nematodes (gin) of small ruminants have created the need for alternative approaches to parasite control. copper oxide wire particles (cowp; 2g) have proven effective in decreasing gin infection in lambs. however, the risk of copper toxicity has limited the usefulness of this approach. recently, smaller doses (0.5 and 1g) have proven effective in gin control, reducing the risk of toxicity. the objective of this study was to examine the ef ...	2006	16574324
immunological aspects of nematode parasite control in sheep.	gastrointestinal nematode parasitism is arguably the most serious constraint affecting sheep production worldwide. economic losses are caused by decreased production, the costs of prophylaxis and treatment, and the death of the infected animals. the nematode of particular concern is haemonchus contortus, which can cause severe blood loss resulting in anemia, anorexia, depression, loss of condition, and eventual death. the control of nematode parasites traditionally relies on anthelmintic treatme ...	2006	16582083
anthelmintic activity of leucaena leucocephala seed extract on haemonchus contortus-infective larvae.		2006	16603554
segregation of natural and experimental gastrointestinal nematode infection in f2 progeny of susceptible suffolk and resistant gulf coast native sheep and its usefulness in assessment of genetic variation.	gastrointestinal nematode parasitism is a concern to small ruminants worldwide. productivity has been compromised because such nematodes, particularly haemonchus contortus, have developed resistance to available anthelmintics. some sheep breeds and lines within breeds are relatively resistant to infection, a trait that may be useful for developing control strategies. suffolk sheep, which are susceptible to infection, were crossed with gulf coast native sheep, which are more resistant to infectio ...	2006	16621290
ovicidal and larvicidal activity of melia azedarach extracts on haemonchus contortus.	haemonchus contortus is responsible for severe economic losses in sheep and goat breeding in the northeast of brazil. however, the effectiveness of control is compromised due to anthelmintic resistance and misuse. in the search for natural anthelmintics, melia azedarach l., a plant indigenous to india but now distributed throughout brazil, was selected due to the reported anthelmintic properties of its seeds. the aim of this study was to evaluate the anthelmintic activity of the seed and leaf ex ...	2006	16621294
further protection studies using recombinant forms of haemonchus contortus cysteine proteinases.	significant levels of protection against haemonchus contortus have been achieved in sheep by vaccination with a cysteine proteinase-enriched fraction (tsbp) isolated from the gut of adult parasites. protection is associated with three cathepsin b-like cysteine proteinases (hmcp 1, 4 & 6). lambs vaccinated with these proteinases, expressed in bacteria as glutathione s-transferase fusion proteins, had significantly reduced (38%) worm burdens compared to challenge controls although, intriguingly, e ...	2006	16629707
identification and characterization of an asparaginyl proteinase (legumain) from the parasitic nematode, haemonchus contortus.	asparaginyl proteinases (or legumains) are a recently identified, novel class of cysteine proteinase which specifically hydrolyse peptide bonds after asparagine residues. legumains have been implicated in the activation of cysteine proteases, particularly cathepsin b-like proteinases which are thought to help degrade the bloodmeal in blood-feeding helminths such as schistosomes, hookworms and other nematode species. an est sequence representing a full-length legumain was identified from the haem ...	2006	16650340
characterisation of teladorsagia circumcincta microsatellites and their development as population genetic markers.	there is a need to develop tools to study the genetics of parasitic nematodes. this is particularly urgent for those species in which anthelmintic resistance is common such as the sheep parasite teladorsagia (ostertagia) circumcincta. the lack of information on the population genetics of such parasites severely limits our ability to study the genetic basis of anthelmintic resistance. this paper presents the results of three approaches used to isolate microsatellite markers from t. circumcincta a ...	2006	16687182
managing anthelmintic resistance in small ruminant livestock of resource-poor farmers in south africa.	gastrointestinal parasitism is one of the most important disease complexes of sheep and goats impacting on the resource-poor livestock farmer. of the responsible nematodes, haemonchus contortus, a blood-sucking worm of the abomasum, poses possibly the greatest threat. over the past several decades, the worm has been controlled through the use of anthelmintics, but the emergence of anthelmintic resistance has threatened this chemotherapeutic approach. in africa, the overall prevalence of anthelmi ...	2006	16700468
haemonchus contortus (nematoda: trichostrongylidae) infection in lambs elicits an unequivocal th2 immune response.	selection of resistant animals and host immunization have been proposed as alternative methods for the control of gastrointestinal nematode parasites. however, a better knowledge of the mechanisms involved in protective immunity against these parasites is required for the development of optimal strategies. in this study, 3 month old inra 401 lambs (n = 81) were allocated into three groups: uninfected control, challenged either once (primary-infected animals) or twice (previously-infected animals ...	2006	16701066
survey of helminths in adult sheep in heilongjiang province, people's republic of china.	the prevalence of helminths in adult sheep was investigated in heilongjiang province, people's republic of china between january 1999 and september 2003. a total of 326 adult sheep representing local breeds (xingjiang fine wool sheep, dongbei fine wool sheep) as well as introduced breeds (merino and charollais) from representative geographical locations in heilongjiang province were slaughtered and examined for the presence of helminths. the worms were examined, counted and identified to species ...	2006	16713098
effect of biological control through the daily application of spores of duddingtonia flagrans in lambs kept under an evasive grazing system in the netherlands.	in 2004, an experiment was carried out to evaluate the effect of biological control through feeding spores of duddingtonia flagrans on parasitic gastroenteritis in lambs, kept under an evasive grazing system. in total 66 lambs were used. forty naturally infected 3-month old ram lambs were weaned in mid june, and divided into four groups of 10 lambs. on 21 june, g1-g4 were moved to four separate virtually clean plots, they were moved after 4 and 8 weeks to similar plots, and housed after 12 weeks ...	2006	16713679
control of haemonchus contortus in goats with a sustained-release multi-trace element/vitamin ruminal bolus containing copper.	the objective of this study was to determine the effectiveness of a sustained-release multi-trace element/vitamin ruminal bolus (teb) containing copper administered to mature does for control of gastrointestinal nematodes (gin) during summer months and during late gestation. haemonchus contortus was the predominant nematode during these trials. in experiment 1, yearling spanish does were untreated or administered teb (n=11/group) on day 0 (august 2005) prior to breeding. in experiment 2, spanish ...	2006	16716521
in vitro screening of six anthelmintic plant products against larval haemonchus contortus with a modified methyl-thiazolyl-tetrazolium reduction assay.	because of the increasing anthelmintic resistance and the impact of conventional anthelmintics on the environment, it is important to look for alternative strategies against gastrointestinal nematodes. phytotherapy could be one of the major options to control these pathologies. extracts or ingredients of six different plant species were tested against exsheathed infective larvae of haemonchus contortus using a modified methyl-thiazolyl-tetrazolium (mtt) reduction assay. pyrantel tartrate was use ...	2006	16725288
[resistance of teladorsagia circumcincta in goats to ivermectin in the netherlands].	resistance of teladorsagia circumcincta in goats to ivermectin in 2005, suspected ivermectin resistance of gastrointestinal nematodes was investigated in 17 goats on a farm in the netherlands, using a faecal egg count reduction test combined with faecal larval cultures. eight goats were treated orally with 0.2 mg/ kg ivermectin on 1 august 2005 and the other nine goats served as untreated controls. faeces were collected from all goats on 1 august and on 12 august. faecal egg counts were reduced ...	2006	16736643
effect of nutritional status and fat reserves on the periparturient immune response to haemonchus contortus infection in sheep.	a study was made of the effect of body fat stored by ewes in early pregnancy on the subsequent immune response to gastrointestinal parasites around parturition. pregnant ewes were given access to a lucerne pelleted diet either ad libitum (h) or at approximately 0.70 of their maintenance requirements (l) from the 42nd day of pregnancy in order to achieve a clearly differentiated level of body reserves by the 90th day of pregnancy. then, all animals were put on the same plane of nutrition till 3 w ...	2006	16737779
molecular characterization of a family of metalloendopeptidases from the intestinal brush border of haemonchus contortus.	substantial protection against the economically important parasitic nematode haemonchus contortus has been achieved by immunizing sheep with a glycoprotein fraction isolated from the intestinal membranes of the worm (h-gal-gp). previous studies showed that one of the major components of h-gal-gp is a family of at least 4 zinc metalloendopeptidases, designated meps 1-4. this paper describes aspects of the molecular architecture of this protease family, including the proteomic analysis of the mep ...	2006	16740178
prospects for exploring molecular developmental processes in haemonchus contortus.	haemonchus contortus of small ruminants is a parasitic nematode of major socio-economic importance world-wide. while there is considerable knowledge of the morphological changes which take place during the life cycle of h. contortus, very little is understood about the molecular and biochemical processes which govern developmental changes in the parasite. recent technological advances and the imminent genomic sequence for h. contortus provide unique opportunities to investigate the molecular bas ...	2006	16759659
naturally occurring variability in some phenotypic markers and correlates of haemonchotolerance in west african dwarf goats in a subhumid zone of nigeria.	west african dwarf (wad) goats of the nigerian subhumid zone generally show strong resistance and resilience to haemonchus contortus in laboratory experiments, although a relatively small proportion are susceptible to infection. little is known about these extremes of response phenotype in nature. therefore, a survey was carried out of gastrointestinal nematode infections in wad goats, with emphasis on abomasal worms, at three goat markets in southern nigeria during the rainy season. faecal samp ...	2006	16764992
towards the implementation of the "basket of options" approach to helminth parasite control of livestock: emphasis on the tropics/subtropics.	the virtual reliance on anthelmintic drugs alone to control internal parasites of livestock is inappropriate and ultimately unsustainable. in the tropics and subtropics, widespread and high levels of anthelmintic resistance, particularly in nematode parasites of small ruminants, is rife. but more to the point, many farmers in these regions of the world are resource poor and cannot afford, or are reluctant to purchase drugs that may also be of dubious quality. as it is with any intervention, the ...	2006	16764993
abundant variation in microsatellites of the parasitic nematode trichostrongylus tenuis and linkage to a tandem repeat.	an understanding of how genes move between and within populations of parasitic nematodes is important in combating the evolution and spread of anthelmintic resistance. much has been learned by studying mitochondrial dna markers, but autosomal markers such as microsatellites have been applied to only a few nematode species, despite their many advantages for studying gene flow in eukaryotes. here, we describe the isolation of 307 microsatellites from trichostrongylus tenuis, an intestinal nematode ...	2006	16765463