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ostertagia ostertagi macrophage migration inhibitory factor is present in all developmental stages and may cross-regulate host functions through interaction with the host receptor.macrophage migration inhibitory factor (mif) of ostertagia ostertagi, an abomasal parasite of cattle, was characterised in the present study. phylogenetic analysis identified at least three o. ostertagi mifs (oos-mifs), each encoded by a distinct transcript: oos-mif-1.1, oos-mif-1.2 and oos-mif-2. oos-mif-2 is only distantly related to oos-mif-1s, but has higher sequence similarity with the caenorhabditis elegans mif2. oos-mif-1.1 and oos-mif-1.2 are similar (93%) and thus collectively referred ...201424583184
a stochastic frontier approach to study the relationship between gastrointestinal nematode infections and technical efficiency of dairy farms.the impact of gastrointestinal (gi) nematode infections in dairy farming has traditionally been assessed using partial productivity indicators. but such approaches ignore the impact of infection on the performance of the whole farm. in this study, efficiency analysis was used to study the association of the gi nematode ostertagia ostertagi on the technical efficiency of dairy farms. five years of accountancy data were linked to gi nematode infection data gained from a longitudinal parasitic moni ...201424731629
the usefulness of dna derived from third stage larvae in the detection of ashworthius sidemi infection in european bison, by a simple polymerase chain reaction.ashworthius sidemi, a blood-sucking nematode, is a primary parasite of asiatic cervides, primarily sika deer (cervus nippon). as a. sidemi infections are common in bison, red and roe deer, and gastrointestinal nematodes are often exchanged between animals, it is possible that other farm animals such as cows and sheep that may use the same pastures can be infected. hence, histopathological changes observed in the walls of the abomasa and duodena of infected wildlife caused by a strong parasite pr ...201424886355
analysis of putative inhibitors of anthelmintic resistance mechanisms in cattle gastrointestinal nematodes.effects of the cytochrome p450 inhibitor piperonyl butoxide and the p-glycoprotein inhibitor verapamil on the efficacy of ivermectin and thiabendazole were studied in vitro in susceptible and resistant isolates of the cattle parasitic nematodes cooperia oncophora and ostertagia ostertagi. the effects of combined use of drug and piperonyl butoxide/verapamil, respectively, were investigated in the egg hatch assay, the larval development assay and the larval migration inhibition assay. the effects ...201424907555
parasite control practices on pasture-based dairy farms in the republic of ireland.dictyocaulus viviparus, ostertagia ostertagi (nematode parasites), and fasciola hepatica (trematode parasite) result in productivity losses on dairy farms and impact on animal health through clinical and sub-clinical disease. parasite control in livestock systems is largely based on the use of chemoprophylactic agents (anthelmintics), grazing management, or a combination of both. the objective of this study was to document current parasite control measures employed by irish dairy farmers in a pr ...201424924698
annual variation in serum antibody concentrations against gastrointestinal nematodes in beef calves from semi-arid rangelands of western canada.sera from calves originating on a 17,000 ha ranch in southeastern alberta, were collected over three consecutive years (2008-2010) at weaning and analysed for the presence of anti-ostertagia antibodies using the svanovir(®)ostertagia ostertagi-ab elisa kit. faecal samples taken at the same time were analysed for presence of nematode eggs using the modified wisconsin faecal flotation technique. mean optical density ratio (odr) values for all calves were similar in 2008 and 2010 while the 2009 val ...201425086494
the parasitic phase of ostertagia ostertagi: quantification of the main life history traits through systematic review and meta-analysis.predictive models of parasite life cycles increase our understanding of how parasite epidemiology is influenced by global changes and can be used to support decisions for more targeted worm control. estimates of parasite population dynamics are needed to parameterize such models. the aim of this study was to quantify the main life history traits of ostertagia ostertagi, economically the most important nematode of cattle in temperate regions. the main parameters determining parasite density durin ...201425229178
activity of ivermectin long-acting injectable (ivomec(®) gold) in first-season grazing cattle exposed to natural challenge conditions in germany.the persistent activity of ivermectin long-acting injection (ivm lai; ivomec® gold, merial; 3.15% ivermectin w/v) against nematode infections of cattle was evaluated under natural challenge conditions. seventy nematode-free brown swiss calves were blocked by pre-treatment bodyweight and allocated randomly to seven groups of 10 animals each: saline (control) at 1 ml/50 kg bodyweight once on day 0 or ivm lai at 1 ml/50 kg bodyweight (630 mcg ivm/kg) on either days 0, 7, 14, 21, 28, or 35. after ho ...201525280515
molecular cloning and characterization of a nematode polyprotein antigen/allergen from the human and animal hookworm ancylostoma ceylanicum.nematodes are unable to synthesize fatty acids de novo and must acquire them from the environment or host. it is hypothesized that two unique classes of fatty acid and retinol binding proteins that nematodes produce (fatty acid and retinol binding (far) and nematode polyprotein antigen/allergen (npa)) are used to meet this need. a partial cdna has been cloned corresponding to four subunits of a putative ancylostoma ceylanicum npa (acenpa). the translated amino acid sequence of acenpa shares sequ ...201425481749
anthelmintic resistance in nematodes of beef cattle in south-west western australia.anthelminthic resistance in nematodes of beef cattle is an emerging issue globally with implications for effective parasite control. the prevalence of resistance in beef cattle in the mediterranean-style climatic zone of south-west western australia was assessed on 19 farms, using faecal egg count reduction tests. pre-treatment faecal worm egg counts were compared with counts at 14 days after treatments with ivermectin (injectable), fenbendazole (oral), or levamisole (oral). a separately grazed ...201525541483
gene expression of abc transporters in cooperia oncophora after field and laboratory selection with macrocyclic lactones.the most widespread helminth parasites of grazing cattle in northern europe are the gastrointestinal nematodes ostertagia ostertagi and cooperia oncophora. heavy reliance on the use of macrocyclic lactone (ml) in cattle has led to world-wide emergence of resistance to this drug class in c. oncophora. there is evidence that members of the atp-binding cassette (abc) transporter family, such as p-glycoproteins (p-gp) and multidrug-resistant proteins (mrp), play a role in resistance to ml. in this s ...201425619799
prevalence and seasonality of bulk milk antibodies against dictyocaulus viviparus and ostertagia ostertagi in irish pasture-based dairy herds.infections with dictyocaulus viviparus and ostertagia ostertagi nematode parasites are of importance to bovine health and production in temperate areas across the world. losses due to these parasites in dairy herds can be considerable due to decreased milk productivity and fertility. however, information on current epidemiological patterns in irish dairy herds is limited. bulk milk samples were collected from a total of 319 dairy farms across the republic of ireland. the d. viviparus samples wer ...201525709092
rapid selection for β-tubulin alleles in codon 200 conferring benzimidazole resistance in an ostertagia ostertagi isolate on pasture.resistance to benzimidazoles (bzs) is widespread in sheep nematodes and increasing in those of cattle. several reasons including the predominant use of pour-on anthelmintics and lack of scales in field conditions lead to under-dosing of cattle and therefore to increased selection pressure. in an field experiment the frequency of bz-resistance associated allele (tac) in codon 200 in the β-tubulin isotype 1 gene of ostertagia ostertagi was monitored over one grazing season (approximately 30 weeks) ...201525725546
controlling nematodes in dairy calves using targeted selective treatments.with increasing concerns of anthelmintic resistance in cattle nematode populations worldwide, there is a need to explore alternative approaches to nematode control. one alternative approach is the use of targeted selective treatments (tst) where only individual animals are treated instead of the entire group. this study reports the findings of a tst approach in dairy calves conducted over their first grazing season (fgs) to control both gastrointestinal nematode and lungworm challenge. ninety-si ...201525770853
measuring larval nematode contamination on cattle pastures: comparing two herbage sampling methods.assessing levels of pasture larval contamination is frequently used to study the population dynamics of the free-living stages of parasitic nematodes of livestock. direct quantification of infective larvae (l3) on herbage is the most applied method to measure pasture larval contamination. however, herbage collection remains labour intensive and there is a lack of studies addressing the variation induced by the sampling method and the required sample size. the aim of this study was (1) to compare ...201525913455
development of a multiplex fluorescence immunological assay for the simultaneous detection of antibodies against cooperia oncophora, dictyocaulus viviparus and fasciola hepatica in cattle.a major constraint for the effective control and management of helminth parasites is the lack of rapid, high-throughput, routine diagnostic tests to assess the health status of individual animals and herds and to identify the parasite species responsible for these helminthoses. the capability of a multiplex platform for the simultaneous detection of three pasture associated parasite species was evaluated and compared to existing elisas.201526084663
resistance of gastrointestinal nematodes to the most commonly used anthelmintics in sheep, cattle and horses in spain.the objective of this study was to evaluate the status of anthelmintic resistance (ar) in ruminants and horses in spain. the efficacy of commonly used macrocyclic lactones (mls) - ivermectin (ivm) and moxidectin (mox) - was measured in sheep, cattle and horses. in addition, albendazole (abz) and levamisole (lev) were evaluated in sheep and oxibendazole (oxi) and pyrantel (pyr) in horses. efficacy was evaluated based on the difference between the arithmetic mean pre- and post-treatment faecal egg ...201526112062
applying a kinetic method to an indirect elisa measuring ostertagia ostertagi antibodies in milk.indirect enzyme-linked immunosorbent assays (elisas) are frequently run as endpoint elisas (e-elisas). however, kinetic elisas (k-elisas) have certain advantages over e-elisas. the objective of this study was to understand the relationship between e-elisa and k-elisa results. specifically, to determine whether it was possible to run both k-elisa and e-elisa on the same plate and establish an appropriate time interval for k-elisa measurements. a normalization method for k-elisa slopes (slope rati ...201526130849
association between dictyocaulus viviparus status and milk production parameters in dutch dairy herds.the objective of this study was to estimate the association between dictyocaulus viviparus bulk tank milk (btm) test results and milk production and milk composition parameters in adult dutch dairy cattle herds. bulk tank milk samples were collected in august and november 2013, and elisa tests were performed. two hundred btm positive (btm+) and 200 btm negative (btm-) herds were selected based on their btm test result of november 2013, obtained from a list of farms that participated in the dutch ...201526298745
comment on bloemhoff et al., 2015. prevalence and seasonality of bulk milk antibodies against dictyocaulus viviparus and ostertagia ostertagi in irish pasture-based dairy herds. vet. parasitol. 209, 108-116. 201526391821
anthelmintic resistance to ivermectin and moxidectin in gastrointestinal nematodes of cattle in europe.anthelmintic resistance has been increasingly reported in cattle worldwide over the last decade, although reports from europe are more limited. the objective of the present study was to evaluate the efficacy of injectable formulations of ivermectin and moxidectin at 0.2 mg per kg bodyweight against naturally acquired gastro-intestinal nematodes in cattle. a total of 753 animals on 40 farms were enrolled in germany (12 farms), the uk (10 farms), italy (10 farms), and france (8 farms). animals wer ...201526448902
the relation between input-output transformation and gastrointestinal nematode infections on dairy farms.efficiency analysis is used for assessing links between technical efficiency (te) of livestock farms and animal diseases. however, previous studies often do not make the link with the allocation of inputs and mainly present average effects that ignore the often huge differences among farms. in this paper, we studied the relationship between exposure to gastrointestinal (gi) nematode infections, the te and the input allocation on dairy farms. although the traditional cost allocative efficiency (c ...201626499290
[a comparative analysis of various antigenic proteins found in haemonchus contortus--a review].many innovative researches on the development and introduction of recombinant vaccines against many economically important parasites were carried out in the 20th century. research continues to hold promise with the development of immunological and molecular approaches for control of these parasites and in this regard it has already been seen that blood-sucking parasites such as haemonchus contortus and ostertagia ostertagi are susceptible to control by vaccines containing "novel" or "concealed" ...201526710767
anthelmintic resistance in gastrointestinal nematodes of dairy cattle in the macalister irrigation district of victoria.to report anthelmintic resistance in gastrointestinal nematode parasites of cattle on commercial dairy farms in the macalister irrigation district of gippsland, victoria.201626814160
impact of chemical structure of flavanol monomers and condensed tannins on in vitro anthelmintic activity against bovine nematodes.plants containing condensed tannins (ct) may have potential to control gastrointestinal nematodes (gin) of cattle. the aim was to investigate the anthelmintic activities of four flavan-3-ols, two galloyl derivatives and 14 purified ct fractions, and to define which structural features of ct determine the anti-parasitic effects against the main cattle nematodes. we used in vitro tests targeting l1 larvae (feeding inhibition assay) and adults (motility assay) of ostertagia ostertagi and cooperia o ...201626888630
sesquiterpene lactone containing extracts from two cultivars of forage chicory (cichorium intybus) show distinctive chemical profiles and in vitro activity against ostertagia ostertagi.the study investigated direct anthelmintic effects of sesquiterpene lactones (sl)-containing extracts from forage chicory against free-living and parasitic stages of ostertagia ostertagi. freeze-dried leaves from chicory cultivars 'spadona' and 'puna ii' were extracted using methanol/water. total sl were further fractionated by solid-phase extraction and resulting extracts were characterised by high-performance liquid chromatography (hplc). o. ostertagi eggs from faeces of mono-infected calves w ...201527120066
anthelmintic effects of forage chicory (cichorium intybus) against gastrointestinal nematode parasites in experimentally infected cattle.two experiments studied the effects of dietary chicory against gastrointestinal nematodes in cattle. in experiment (exp.) 1, stabled calves were fed chicory silage (chi1; n = 9) or ryegrass/clover hay (ctl1; n = 6) with balanced protein/energy intakes between groups. after 16 days, all calves received 10 000 ostertagia ostertagi and 66 000 cooperia oncophora third-stage larvae (l3) [day (d) 0 post-infection (p.i.)]. in exp. 2, calves were assigned to pure chicory (chi2; n=10) or ryegrass/clover ...201627173405
anti-parasitic activity of pelleted sainfoin (onobrychis viciifolia) against ostertagia ostertagi and cooperia oncophora in calves.increasing anthelmintic-resistance in nematodes of ruminants emphasises the need for sustainable parasite control. condensed tannin-containing legume forages such as sainfoin (onobrychis viciifolia) have shown promising anthelmintic properties in small ruminants but this has never been explored in cattle. therefore, our aim was to examine the efficacy of sainfoin against cattle nematodes in vivo.201627283323
the level of embryonation influences detection of ostertagia ostertagi eggs by semi-quantitative pcr.the internal transcribed spacer 2 (its2) is a candidate diagnostic marker of the pathogenic cattle nematode ostertagia ostertagi. the aims of this study were: (i) to document and quantify how the development of o. ostertagi eggs affects its2 copies under different storage conditions, and (ii) to suggest optimal storage conditions for faecal samples in a diagnostic pipeline that involves detection and semi-quantification by real-time semi-quantitative polymerase chain reaction (qpcr).201627357701
explaining variability in first grazing season heifer growth combining individually measured parasitological and clinical indicators with exposure to gastrointestinal nematode infection based on grazing management practice.the objective of our study was to explain the variability of average daily weight gain (adwg) due to gastrointestinal nematode (gin) infection for 291 non treated first grazing season (fgs) heifers, from 12 independent groups in the western part of france, by combining parasitological and clinical indicators at individual level and grazing management indicators at group level. parasitological indicators were faecal egg count (fec), anti ostertagia ostertagi antibody level (ostertagia odr), and p ...201627369576
host protective asp-based vaccine against the parasitic nematode ostertagia ostertagi triggers nk cell activation and mixed igg1-igg2 response.the mucus-dwelling parasite ostertagia ostertagi is one of the most important gastrointestinal nematodes in cattle. our group has previously demonstrated the protective capacity of a vaccine against this parasite based on a native activation-associated secreted protein asp1 (nasp) in combination with the saponin adjuvant quila. the aim of the current study was to analyse the effect of both antigen and adjuvant on the cellular and humoral vaccine-induced immune responses by comparing the native a ...201627403891
a simulation model to investigate interactions between first season grazing calves and ostertagia ostertagi.a dynamic, deterministic model was developed to investigate the consequences of parasitism with ostertagia ostertagi, the most prevalent and economically important gastrointestinal parasite of cattle in temperate regions. interactions between host and parasite were considered to predict the level of parasitism and performance of an infected calf. key model inputs included calf intrinsic growth rate, feed quality and mode and level of infection. the effects of these varied inputs were simulated o ...201627514906
the efficacy and plasma profiles of abamectin plus levamisole combination anthelmintics administered as oral and pour-on formulations to cattle.in phase i, faecal egg count reduction tests (fecrt) were conducted on six commercial cattle farms to compare the performance of two pour-on and one oral combination anthelmintic. groups of 12-15 calves were sampled for faecal nematode egg count (fec) before treatment with either abamectin oral, levamisole oral, an abamectin+levamisole oral combination or one of two abamectin+levamisole combination pour-ons. samples were collected again 14days after treatment to calculate the percentage reductio ...201627523943
a stochastic model to investigate the effects of control strategies on calves exposed to ostertagia ostertagi.predicting the effectiveness of parasite control strategies requires accounting for the responses of individual hosts and the epidemiology of parasite supra- and infra-populations. the first objective was to develop a stochastic model that predicted the parasitological interactions within a group of first season grazing calves challenged by ostertagia ostertagi, by considering phenotypic variation amongst the calves and variation in parasite infra-population. model behaviour was assessed using v ...201627573532
climate-driven longitudinal trends in pasture-borne helminth infections of dairy cattle.helminth parasites of grazing ruminants are highly prevalent globally and impact negatively on animal productivity and food security. there is a growing concern that climate change increases helminth disease frequency and intensity. in europe, these concerns stem from case reports and theoretical life cycle models assessing the effects of climate change scenarios on helminth epidemiology. we believe this study is the first to investigate climate-driven trends in helminth infections of cattle on ...201627771256
abomasal mucosal immune responses of cattle with limited or continuous exposure to pasture-borne gastrointestinal nematode parasite infection.it has been well documented that cattle raised on pasture are slow in weight gain when compared to those fed with grain. inflammation in the digestive system commonly caused by pasture-transmitted gastrointestinal (gi) nematode parasites that could negatively impact feed conversion has never been compared in cattle raised with no pasture exposure (npe, uninfected), limited pasture exposure (lpe, exposure until weaning), or continuous pasture exposure (cpe, life time exposure). in the present stu ...201627809966
confirmation of ivermectin resistance in ostertagia ostertagi in cattle in new zealand.six suspected cases of ivermectin resistance in ostertagia spp. in cattle were investigated after routine anthelmintic efficacy testing on commercial farms. on four farms a comprehensive faecal egg count reduction test (fecrt) was undertaken using oral formulations of ivermectin (0.2mg/kg), albendazole (10mg/kg) and levamisole (7.5mg/kg) while on two farms only ivermectin was tested. the proportions of ostertagia spp. in the untreated control and post-treatment larval cultures were used to appor ...201627809969
efficacy of ivermectin against gastrointestinal nematodes of cattle in denmark evaluated by different methods for analysis of faecal egg count reduction.the efficacy of ivermectin (ivm) against gastrointestinal nematodes in danish cattle was assessed by faecal egg count reduction test (fecrt). six cattle farms with history of clinical parasitism and avermectin use were included. on the day of treatment (day 0), 20 naturally infected calves per farm (total n = 120) were stratified by initial faecal egg counts (fec) and randomly allocated to a treatment group dosed with 0.2 mg ivm kg(-1) body weight s.c. (ivm; n = 10) or an untreated control group ...201627835769
climate influences assemblages of abomasal nematodes of sheep on steppe pastures in the east of algeria.it is a common view that assemblages of parasitic nematodes are influenced by climatic conditions; however, there are only a few articles available regarding those that infect farm animals. we investigated the relationship between climate variables and infection with abomasal trichostrongyles in 335 1-year-old rams grazed on steppe pastures in eastern algeria. abomasa were collected from 12 local slaughterhouses located in four climatic areas (from humid to arid) and the worms extracted, identif ...201627905269
modelling the consequences of targeted selective treatment strategies on performance and emergence of anthelmintic resistance amongst grazing calves.the development of anthelmintic resistance by helminths can be slowed by maintaining refugia on pasture or in untreated hosts. targeted selective treatments (tst) may achieve this through the treatment only of individuals that would benefit most from anthelmintic, according to certain criteria. however tst consequences on cattle are uncertain, mainly due to difficulties of comparison between alternative strategies. we developed a mathematical model to compare: 1) the most 'beneficial' indicator ...201627915061
condensed tannins in the gastrointestinal tract of cattle after sainfoin (onobrychis viciifolia) intake and their possible relationship with anthelmintic effects.condensed tannins' (cts) fate along the digestive tract of ruminants may account for the variable efficacy of cts against gastrointestinal nematodes. we analyzed cts in the digesta of cattle fed sainfoin. with the acetone-butanol-hcl assay, the total cts concentrations in the digesta were close to those in the diets (6.3 and 1.5% of dm in experiments 1 and 2, respectively); thus, cts remained potentially largely undegraded/unabsorbed. with the thiolysis assay, cts concentration was much higher i ...201728120611
a multi-country study to assess the effect of a treatment with moxidectin pour-on during the dry period on milk production in dairy cows.a randomized clinical study was conducted in a total of 45 commercial dairy farms in france (14 farms), germany (28 farms) and the uk (3 farms) to evaluate the effect of an anthelmintic treatment on milk yield in the subsequent lactation. a total of 1287 animals with suspected exposure to ostertagia ostertagi were included in the study. animals were treated during the dry period (7-77days before parturition) with moxidectin pour-on (cydectin(®) 0.5% pour-on, zoetis; 638 animals) or left untreate ...201728259556
economic modelling of grazing management against gastrointestinal nematodes in dairy cattle.grazing management (gm) interventions, such as reducing the grazing time or mowing pasture before grazing, have been proposed to limit the exposure to gastrointestinal (gi) nematode infections in grazed livestock. however, the farm-level economic effects of these interventions have not yet been assessed. in this paper, the economic effects of three gm interventions in adult dairy cattle were modelled for a set of flemish farms: later turnout on pasture (gm1), earlier housing near the end of the ...201728288768
characterization of ostertagia ostertagi annexin-like proteins at different developmental stages.ostertagiosis remains an economically important parasitic disease in cattle in the temperate regions of the world. repeated exposures to ostertagia ostertagi in calves cause significant pathology in the abomasum but elicit little protective immunity. the larvae use the host's gastric glands as a niche for development, where the parasite completes its parasitic stages, while in the gastric glands, the larvae must down-regulate the host inflammatory immune responses. annexin (anx) a1, commonly fou ...201728378195
modelling the impacts of pasture contamination and stocking rate for the development of targeted selective treatment strategies for ostertagia ostertagi infection in calves.a simulation study was carried out to assess whether variation in pasture contamination or stocking rate impact upon the optimal design of targeted selective treatment (tst) strategies. two methods of tst implementation were considered: 1) treatment of a fixed percentage of a herd according to a given phenotypic trait, or 2) treatment of individuals that exceeded a threshold value for a given phenotypic trait. four phenotypic traits, on which to base treatment were considered: 1) average daily b ...201728408216
characterization of a novel aspartyl protease inhibitor from haemonchus contortus.aspartyl protease inhibitor (api) was thought to protect intestinal parasitic nematodes from their hostile proteolytic environment. studies on ostertagia ostertagi, ascaris suum and brugia malayi indicated that aspins might play roles in nematode infection. in a recent study, proteins differentially expressed between free-living third-stage larvae (l3) and activated l3 (xl3) of haemonchus contortus were identified by 2d-dige. api was found downregulated in xl3 when compared with l3. however, the ...201728420411
unusual population genetics of a parasitic nematode: mtdna variation within and among populations.very little is known about the distribution of genetic variance within and among populations of parasitic helminths. in this study we used mitochondrial dna (mtdna) restriction fragment analysis to describe the population genetic structure of ostertagia ostertagi, a nematode parasite of cattle, in the united states. estimates of within-population mtdna diversity are 5 to 10 times greater than typical estimates reported for species in other taxa. although populations are genetically differentiate ...199228564029
economic assessment of ostertagia ostertagi and fasciola hepatica infections in dairy cattle herds in germany using paracalc(®).the aim of the current study was to estimate economic costs of ostertagia ostertagi and fasciola hepatica infections in dairy cattle herds in germany using the online calculation programme paracalc(®). following a questionnaire, survey data were available from 464 farms in 14 federal states. on those farms bulk tank milk (btm) samples and additionally up to six serum samples collected from first season grazing calves were analysed, using a commercially available elisa (boehringer ingelheim svano ...201728576343
[anthelmintic resistance in ruminants: development, diagnostics, and procedures].anthelmintic resistance of gastrointestinal nematodes in small ruminants, but also in cattle and horses, is now found worldwide. the reason for increasing anthelmintic resistance is, in particular, the extensive use of all the anthelmintic agents available on the market. a non-targeted use leads to the selection of naturally occurring resistance genes within parasite populations. the most practical method for evaluating the efficacy of an anthelmintic is the fecal egg-count reduction test. to re ...201728765867
the use of nemabiome metabarcoding to explore gastro-intestinal nematode species diversity and anthelmintic treatment effectiveness in beef calves.next-generation deep amplicon sequencing, or metabarcoding, has revolutionized the study of microbial communities in humans, animals and the environment. however, such approaches have yet to be applied to parasitic helminth communities. we recently described the first example of such a method - nemabiome sequencing - based on deep-amplicon sequencing of internal transcribed spacer 2 (its-2) rdna, and validated its ability to quantitatively assess the species composition of cattle gastro-intestin ...201728797791
establishment rate of cattle gastrointestinal nematodes in farmed red deer (cervus elaphus).red deer can be infected with some gastrointestinal nematodes (gin) of cattle but it is unknown to what extent. an indoor study was conducted to determine the establishment rate of cattle gin in young deer. five young calves and 5 young red deer were used. they were effectively treated with anthelmintics when housed and then infected 2 weeks later. after four weeks they were killed for total worm counts. establishment rates were assessed comparing worm counts to the infective dose which were ide ...201728807276
anthelmintic effects of forage chicory (cichorium intybus) against free-living and parasitic stages of cooperia oncophora.chicory shows great promise as an anthelmintic forage for grazing ruminants that can reduce reliance on anti-parasitic drugs. recently, we reported potent anthelmintic effects of chicory-based diets in infected cattle with significant reductions in worm burdens of the abomasal nematode ostertagia ostertagi, whilst no apparent activity was observed against the small intestinal parasite cooperia oncophora. to explore this discrepancy, we investigated direct anthelmintic effects of forage chicory a ...201728807295
herd-level prevalence of selected endemic infectious diseases of dairy cows in great britain.to implement appropriate and effective disease control programs at the national level, up-to-date and unbiased information on disease frequency is needed. the aim of this study was to estimate the prevalence of selected endemic infectious diseases in the population of dairy herds in great britain. bulk milk tank (bmt) samples from 225 randomly selected dairy farms, stratified by region and herd size, were tested for antibodies against bovine viral diarrhea virus (bvdv), bovine herpesvirus type 1 ...201728843682
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