The Experts below are selected from a list of 81942 Experts worldwide ranked by ideXlab platform
Peter J Waller - One of the best experts on this subject based on the ideXlab platform.
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towards the implementation of the basket of options approach to helminth Parasite Control of livestock emphasis on the tropics subtropics
Veterinary Parasitology, 2006Co-Authors: R C Krecek, Peter J WallerAbstract:Abstract 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 benefits must outweigh the costs. This is not only in terms of conventional parameters such as reduced mortality and increasing productivity (meat, milk, fibre and traction power) of livestock, but also within the broad framework of helminths of veterinary/human importance, the aim should be a positive impact on reducing the threat of helminth zoonoses. However, understanding the issues involved and education of the end-users (farmers) is of fundamental importance, before any internal Parasite Control program should be promoted. Within the above context, we provide examples of how the “basket of options” approach could be adopted for the Control of three quite disparate helminth problems in the tropics and subtropics, viz.: strongyle nematode infections of donkeys, the Taenia solium cysticercosis/taeniosis problem of pig and man and Haemonchus contortus infections in small ruminants. The “best practice” approaches can be defined as those “basket of options” that are practical, affordable, available and appropriate, whether to the commercial producer, or to the resource-poor farmer. Constraints that may restrict applying such options are accessibility to, and affordability of, suitable remedies and above all, the availability of information needed to make informed decisions in this regard.
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evaluation of gastro intestinal nematode Parasite Control strategies for first season grazing cattle in sweden
Veterinary Parasitology, 2003Co-Authors: S O Dimander, Johan Hoglund, A Uggla, Eva Sporndly, Peter J WallerAbstract:A three-year grazing experiment (1998-2000) was conducted with first-season grazing cattle (FSGC) on improved pastures in central-eastern Sweden. Comparison was made between five groups with 10 calves in each group where four of these were set stocked and either (1) untreated, (2) ivermectin bolus treated, (3) subjected to biological Control with the nematophagous fungus Duddingtonia flagrans, or (4) treated with a copper wire particle bolus. The fifth treatment was an evasive grazing strategy, whereby untreated calves were turned out onto pasture used by older cattle the previous year and then these calves were moved to silage aftermath in mid-July. To introduce low-levels of Parasite infection to the experiment, each animal received a 'priming dose' of approximately 5,000 Ostertagia ostertagi and 5,000 Cooperia oncophora infective third stage larvae immediately prior to the start of the first grazing year of the trial. Results showed that efficient and sustainable Parasite Control of FSGC was possible to achieve without the use of anthelmintics by using turnout pastures that the previous year had been grazed by older cattle, in combination with a mid-July move to aftermath leys. Biological Control also proved beneficial but the efficacy was impaired if high faecal egg counts coincided with rapid dung pat degradation due to heavy rainfall. No indication of Parasite Control was observed with the copper wire particle bolus. It was also demonstrated that the impact of gastrointestinal (GI) parasitism varied between years and that the level of overwintering contamination is important but likewise, is unpredictable. Although faecal egg counts in 1999 were low, due both to a delayed turnout and drought for the major part of the grazing season, deposited eggs successfully developed to infective larvae and overwintered in large numbers. The population of overwintered infective larvae at the time of turnout in early May played an important role in the course of infection in 2000 and resulted in an average 65 kg advantage of the ivermectin treated calves compared with the untreated calves.Thus, this three-year grazing experiment has emphasised the importance of subclinical gastrointestinal nematode infections in FSGC in Sweden. In addition, the study has shown that adequate Parasite Control may be achievable without the use of anthelmintics.
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nematode Parasite Control of livestock in the tropics subtropics the need for novel approaches
International Journal for Parasitology, 1997Co-Authors: Peter J WallerAbstract:Because Parasites are more abundant, small ruminants in the tropical/subtropical regions of the world experience much greater ravages from internal parasitic disease than those in the temperate regions. In the tropics/subtropics, the limiting ecological factor influencing the severity of parasitism is rainfall, as temperatures almost always favour hatching and development of the free-living stages. Attempts to expand sheep and goat production by replacing traditional village production systems, which rarely involve anthelmintic treatment, with large-scale intensive commercial enterprises invariably induce complete reliance on anthelmintics to Control nematode Parasites. This has led to the widespread development of high level, multiple anthelmintic resistance throughout the tropics/subtropics, and in certain regions this has reached the ultimate disastrous scenario of total chemotherapeutic failure. Immediate concerted efforts are needed to resolve this crisis. Significant benefits are likely to emerge from research into non-chemotherapeutic approaches to nematode Parasite Control, such as grazing management, worm vaccines, breed selection and biological Control. However, it is likely that none, in isolation or collectively, will completely replace the need for effective anthelmintics. What is needed is the integration of all methods of Parasite Control as they come to hand, with the underlying aim of reducing the use and thus preserving the effectiveness of anthelmintics. Although cheap and simple procedures, based on sound epidemiological principles, can achieve dramatic benefits in worm Control, they have been poorly adopted by livestock owners. Clearly then, the greatest need is for technology transfer and education programmes, but these activities are generally found to be chronically under-resourced.
P J Waller - One of the best experts on this subject based on the ideXlab platform.
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Parasite Control practices on swedish horse farms
Acta Veterinaria Scandinavica, 2007Co-Authors: Eva Osterman Lind, P J Waller, A Uggla, Erik Rautalinko, David A Morrison, Johan HoglundAbstract:Virtually all horses are infected with helminth Parasites. For some decades, the Control of Parasites of Swedish horses has been based on routine treatments with anthelmintics, often several times per year. Since anthelmintic resistance is becoming an increasing problem it is essential to develop more sustainable Control strategies, which are adapted to different types of horse management. The aim of this study was to obtain information on practices used by Swedish horse owners for the Control of endoParasites. A questionnaire with 26 questions about management practices and Parasite Control routines was posted to 627 randomly selected horse establishments covering most types of horse management in Sweden. The response rate was good in all categories of respondents (66–78%). A total of 444 questionnaires were used in the analyses. It was found that virtually all horses had access to grazing areas, usually permanent. Generally, pasture hygiene was infrequently practiced. Thirty-six percent of the respondents clipped or chain harrowed their pastures, whereas weekly removal of faeces from the grazing areas was performed by 6% of the respondents, and mixed or rotational grazing with other livestock by 10%. The number of anthelmintic treatments per year varied from 1–8 with an average of 3.2. Thirty-eight percent considered late autumn (Oct-Dec) to be the most important time for deworming. This finding, and an increased use of macrocyclic lactones in the autumn, suggests a concern about bot flies, Gasterophilus intestinalis. Only 1% of the respondents stated that faecal egg counts (FEC) were performed on a regular basis. The relatively high cost of FEC analyses compared to purchase of anthelmintics was thought to contribute to the preference of deworming without a previous FEC. From the study it was evident that all categories of horse owners took advice mainly from veterinarians. The results show that routines for endoParasite Control can be improved in many horse establishments. To increase the knowledge of equine endoParasite Control and follow the recommendations for how to reduce the spread of anthelmintic resistance, a closer collaboration between parasitologists and veterinary practitioners is desirable.
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sustainable nematode Parasite Control strategies for ruminant livestock by grazing management and biological Control
Animal Feed Science and Technology, 2006Co-Authors: P J WallerAbstract:Internal parasitism constitutes one of the greatest disease problems in grazing livestock worldwide. Control of these Parasites is now becoming a serious concern, particularly in the small ruminant industries, due to the widespread and rapid development of resistance to chemotherapy. The broad-spectrum drugs (anthelmintics) used in the Control of nematode Parasites fall into just three classes viz. the benzimidazoles, imidothiazoles and macrocyclic lactones. Resistance to all three drug classes now occurs in the major nematode Parasites of sheep and goats throughout the world. This is largely the result of a more-or-less complete reliance on anthelmintics for worm Control. By analogy then, any specific Parasite Control method may be unsustainable when used in isolation. The more choices and the greater variety of Controls used in combination, rather than relying almost solely on anthelmintics, the longer effective worm Control can be expected. Grazing management strategies and biological Control offer two non-chemical methods of Parasite Control, which have proven effectiveness. These should form part of integrated nematode Parasite Control programmes for grazing livestock with the objective of maintaining long-term sustainability.
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global perspectives on nematode Parasite Control in ruminant livestock the need to adopt alternatives to chemotherapy with emphasis on biological Control
Animal Health Research Reviews, 2003Co-Authors: P J WallerAbstract:Effective, sustainable Control of nematode Parasites of grazing livestock is becoming evermore challenging and difficult. This is largely due to two contrasting issues. One is the rapid escalation of resistance to anthelmintic drugs, which is arguably the greatest problem now facing the small ruminant industries worldwide. Secondly, there is the increasing trend towards organic farming, in which there is prohibition of the prophylactic use of all chemical compounds. Livestock producers urgently need non-chemotherapeutic alternatives in Parasite Control. Researchers have responded to this challenge and a variety of quite different approaches have been the subject of intense investigation in many countries for several decades now. These vary in relation to their stage of development for on-farm use, their utility, and their applicability across the spectrum of grazing livestock enterprises throughout the world. One relatively recent innovation is the biological Control approach to nematode Parasites. This has now reached the stage of commercialization. This review focuses on these issues and provides an overview of the possible ways in which the biological Control of nematode Parasites could be employed in grazing ruminant livestock systems worldwide.
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towards sustainable nematode Parasite Control of livestock
Veterinary Parasitology, 1993Co-Authors: P J WallerAbstract:Farmers worldwide have come to expect, and rely almost exclusively on, broad-spectrum anthelmintics to effectively Control nematode Parasites amongst their livestock. However, the threats of resistance, residues and ecotoxicity are of increasing concern to the future of chemotherapy. It is imperative that sustainable Parasite Control schemes be developed and implemented which will integrate a range of techniques to minimise anthelmintic use and still maintain high levels of profitability of the farming enterprise. At present, these need to focus on the better use of existing drugs to maximise their effectiveness and minimise the selection for resistance and impact on the environment. New drugs should also be used according to these principles. In the future it is expected that other non-chemotherapeutic options will become available, e.g. helminth vaccines, resistant hosts, biological Control, nematode growth regulators, which will revolutionize the current thinking on nematode Parasite Control of livestock.
Ray M. Kaplan - One of the best experts on this subject based on the ideXlab platform.
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equine Parasite Control and the role of national legislation a multinational questionnaire survey
Veterinary Parasitology, 2018Co-Authors: A M Becher, Ray M. Kaplan, D C K Van Doorn, Kurt Pfister, Martin Reist, Martin K. NielsenAbstract:Abstract Experts recommend a change in the Control of equine Parasites across the world in order to adopt a surveillance-based approach utilizing Parasite faecal egg counts (FEC). Several European countries have implemented prescription-only restrictions of anthelmintic usage by law, which is in stark contrast to US, where all anthelmintic products continue to be available over the counter. This study aimed to describe and compare equine Parasite Control strategies employed in Germany, Austria, the Netherlands, US, and Denmark. An invitation to participate in an online questionnaire survey was published on a large equine news website in each of the participating countries. The main focus of the study was on usage of FEC and anthelmintic treatment intensity in three different equine age groups; foals, 1–3 year-olds and >3 years old. A total of 3092 respondents participated in the study. Danish respondents used significantly more faecal analyses in their Parasite Control strategies than participants from the other four countries (p
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equine Parasite Control under prescription only conditions in denmark awareness knowledge perception and strategies applied
Veterinary Parasitology, 2014Co-Authors: Martin K. Nielsen, Ray M. Kaplan, D C K Van Doorn, Kurt Pfister, Martin Reist, A M BecherAbstract:Due to widespread development of anthelmintic resistance in equine Parasites, recommendations for their Control are currently undergoing marked changes with a shift of emphasis toward more coprological surveillance and reduced treatment intensity. Denmark was the first nation to introduce prescription-only restrictions of anthelmintic drugs in 1999, but other European countries have implemented similar legislations over recent years. A questionnaire survey was performed in 2008 among Danish horse owners to provide a current status of practices and perceptions with relation to Parasite Control. Questions aimed at describing the current use of coprological surveillance and resulting anthelmintic treatment intensities, evaluating knowledge and perceptions about the importance of various attributes of Parasite Control, and assessing respondents' willingness to pay for advice and Parasite surveillance services from their veterinarians. A total of 1060 respondents completed the questionnaire. A large majority of respondents (71.9%) were familiar with the concept of selective therapy. Results illustrated that the respondents' self-evaluation of their knowledge about Parasites and their Control associated significantly with their level of interest in the topic and their type of education (P<0.0001). The large majority of respondents either dewormed their horses twice a year and/or performed two fecal egg counts per horse per year. This approach was almost equally pronounced in foals, horses aged 1-3 years old, and adult horses. The respondents rated prevention of parasitic disease and prevention of drug resistance as the most important attributes, while cost and frequent fecal testing were rated least important. Respondents' actual spending on Parasite Control per horse in the previous year correlated significantly with the amount they declared themselves willing to spend (P<0.0001). However, 44.4% declared themselves willing to pay more than what they were spending. Altogether, results indicate that respondents were generally familiar with equine Parasites and the concept of selective therapy, although there was some confusion over the terms small and large strongyles. They used a large degree of fecal surveillance in all age groups, with a majority of respondents sampling and/or treating around twice a year. Finally, respondents appeared willing to spend money on Parasite Control for their horses. It is of concern that the survey suggested that foals and young horses are treated in a manner very similar to adult horses, which is against current recommendations. Thus, the survey illustrates the importance of clear communication of guidelines for equine Parasite Control.
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an evidence based approach to equine Parasite Control it ain t the 60s anymore
Equine Veterinary Education, 2010Co-Authors: Ray M. Kaplan, M K NielsenAbstract:Summary Most veterinarians continue to recommend anthelmintic treatment programmes for horses that derive from knowledge and concepts more than 40 years old. However, much has changed since these recommendations were first introduced and current approaches routinely fail to provide optimal or even adequate levels of Parasite Control. There are many reasons for this. Recent studies demonstrate that anthelmintic resistance in equine Parasites is highly prevalent and multiple-drug resistance is common in some countries, but few veterinarians take this into account when making treatment decisions or when recommending rotation of anthelmintics. Furthermore, the current approach of treating all horses at frequent intervals was designed specifically to Control the highly pathogenic large strongyle, Strongylus vulgaris. But this Parasite is now quite uncommon in managed horses in most of the world. Presently, the cyathostomins (small strongyles) are the principal parasitic pathogens of mature horses. The biology and pathogenesis of cyathostomins and S. vulgaris are very different and therefore require an entirely different approach. Furthermore, it is known that Parasites are highly over-dispersed in hosts, such that a small percentage of hosts harbour most of the Parasites. The common practices of recommending the same treatment programme for all horses despite great differences in Parasite burdens, recommending prophylactic treatment of all horses without indication of parasitic disease or knowing what species of Parasites are infecting the horses, recommending use of drugs without knowledge of their efficacy and failing to perform diagnostic (faecal egg count) surveillance for estimating Parasite burdens and determining treatment efficacy, are all incompatible with current standards of veterinary practice. Consequently, it is necessary that attitudes and approaches to Parasite Control in horses undergo a complete overhaul. This is best achieved by following an evidence-based approach that takes into account all of these issues and is based on science, not tradition.
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climatic influences on development and survival of free living stages of equine strongyles implications for worm Control strategies and managing anthelmintic resistance
Veterinary Journal, 2007Co-Authors: M K Nielsen, Ray M. Kaplan, S M Thamsborg, J Monrad, S N OlsenAbstract:Abstract Development of resistance to anthelmintic drugs by horse strongyles constitutes a growing threat to equine health because it is unknown when new drug classes can be expected on the market. Consequently, Parasite Control strategies should attempt to maintain drug efficacy for as long as possible. The proportion of a Parasite population that is not exposed to anthelmintic treatment is described as being “in refugia” and although many factors affect the rate at which resistance develops, levels of refugia are considered the most important as these Parasites are not selected by treatment and so provide a pool of sensitive genes in the population. Accordingly, treatment should be avoided when pasture refugia are small because such treatments will place significant selection pressure for resistance on worm populations. Given this new paradigm for Parasite Control, it has become important to identify seasons and circumstances wherein refugia are diminished. Free-living stages of equine strongyles are highly dependent on climatic influences, and this review summarises studies of strongyle development and survival under laboratory and field conditions in Northern (cool) temperate, Southern (warm) temperate and subtropical/tropical climates. In Northern temperate climates, refugia are smallest during the winter. In contrast, refugia are lowest during the summer in warm temperate and subtropical/tropical climates. Although adverse seasonal changes clearly have significant effects on the ability of free living stages of strongyle nematode Parasites to survive and develop, available data suggest that climatic influences cannot effectively “clean” pastures from one grazing season to the next.
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drug resistance in nematodes of veterinary importance a status report
Trends in Parasitology, 2004Co-Authors: Ray M. KaplanAbstract:Reports of drug resistance have been made in every livestock host and to every anthelmintic class. In some regions of world, the extremely high prevalence of multi-drug resistance (MDR) in nematodes of sheep and goats threatens the viability of small-ruminant industries. Resistance in nematodes of horses and cattle has not yet reached the levels seen in small ruminants, but evidence suggests that the problems of resistance, including MDR worms, are also increasing in these hosts. There is an urgent need to develop both novel non-chemical approaches for Parasite Control and molecular assays capable of detecting resistant worms.
Steven M Singer - One of the best experts on this subject based on the ideXlab platform.
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complement activation by giardia duodenalis Parasites through the lectin pathway contributes to mast cell responses and Parasite Control
Infection and Immunity, 2016Co-Authors: Ernest A Tako, Steven M SingerAbstract:Infection with Giardia duodenalis is one of the most common causes of diarrheal disease in the world. While numerous studies have identified important contributions of adaptive immune responses to Parasite Control, much less work has examined innate immunity and its connections to the adaptive response during this infection. We explored the role of complement in immunity to Giardia using mice deficient in mannose-binding lectin (Mbl2) or complement factor 3a receptor (C3aR). Both strains exhibited delayed clearance of Parasites and a reduced ability to recruit mast cells in the intestinal submucosa. C3aR-deficient mice had normal production of antiParasite IgA, butex vivo T cell recall responses were impaired. These data suggest that complement is a key factor in the innate recognition of Giardia and that recruitment of mast cells and activation of T cell immunity through C3a are important for Parasite Control.
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transcriptomic analysis of the host response to giardia duodenalis infection reveals redundant mechanisms for Parasite Control
Mbio, 2013Co-Authors: Ernest A Tako, Maryam F Hassimi, Steven M SingerAbstract:ABSTRACT The immune system has numerous mechanisms that it can use to combat pathogens and eliminate infections. Nevertheless, studies of immune responses often focus on single pathways required for protective responses. We applied microarray analysis of RNA in order to investigate the types of immune responses produced against infection with the intestinal pathogen Giardia duodenalis. Infection with G. duodenalis is one of the most common causes of diarrheal disease in the world. While several potential antiparasitic effector mechanisms, including complement lysis, nitric oxide (NO), and α-defensin peptides, have been shown to inhibit Parasite growth or kill Giardia in vitro , studies in vivo have thus far shown clear roles only for antibody and mast cell responses in Parasite Control. A total of 96 transcripts were identified as being upregulated or repressed more than 2-fold in the small intestine 10 days following infection. Microarray data were validated using quantitative PCR. The most abundant category of transcripts was antibody genes, while the most highly induced transcripts were all mast cell proteases. Among the other induced transcripts was matrix metalloprotease 7 (Mmp7), the protease responsible for production of mature α-defensins in mice. While infections in Mmp7-deficient mice showed only a small increase in Parasite numbers, combined genetic deletion of Mmp7 and inducible nitric oxide synthase (iNOS, Nos2) or pharmacological blockade of iNOS in Mmp7-deficient mice resulted in significant increases in Parasite loads following infection. Thus, α-defensins and NO are redundant mechanisms for Control of Giardia infections in vivo . IMPORTANCE The immune system has multiple weapons which it uses to help Control infections. Many infections result in activation of several of these response mechanisms, but it is not always clear which responses actually contribute to Control of the pathogen and which are bystander effects. This study used the intestinal Parasite Giardia duodenalis to examine the redundancy in immune responses during infections in mice. Our results showed that at least four distinct mechanisms are activated following infections. Furthermore, by blocking two pathways at the same time, we showed that both mechanisms contribute to Control of the infection, whereas blocking single responses showed no or minimal effect in these cases.
Martin K. Nielsen - One of the best experts on this subject based on the ideXlab platform.
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equine Parasite Control and the role of national legislation a multinational questionnaire survey
Veterinary Parasitology, 2018Co-Authors: A M Becher, Ray M. Kaplan, D C K Van Doorn, Kurt Pfister, Martin Reist, Martin K. NielsenAbstract:Abstract Experts recommend a change in the Control of equine Parasites across the world in order to adopt a surveillance-based approach utilizing Parasite faecal egg counts (FEC). Several European countries have implemented prescription-only restrictions of anthelmintic usage by law, which is in stark contrast to US, where all anthelmintic products continue to be available over the counter. This study aimed to describe and compare equine Parasite Control strategies employed in Germany, Austria, the Netherlands, US, and Denmark. An invitation to participate in an online questionnaire survey was published on a large equine news website in each of the participating countries. The main focus of the study was on usage of FEC and anthelmintic treatment intensity in three different equine age groups; foals, 1–3 year-olds and >3 years old. A total of 3092 respondents participated in the study. Danish respondents used significantly more faecal analyses in their Parasite Control strategies than participants from the other four countries (p
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Parasite Control strategies used by equine owners in the united states a national survey
Veterinary Parasitology, 2018Co-Authors: Martin K. Nielsen, M A Branan, A M Wiedenheft, R Digianantonio, L P Garber, Christine A Kopral, A M Phillippitaylor, Josie L TraubdargatzAbstract:Abstract The widespread occurrence of anthelmintic resistance in equine Parasites across the world has led to recommendations of fecal egg count-based Parasite programs to reduce treatment intensity and thereby delay further development of resistance as much as possible. The most recent study describing equine Parasite Control in the United States was conducted 20 years ago, and little is known about current strategies employed. This study was part of the National Animal Health Monitoring Systems (NAHMS) Equine 2015 Study, and aimed to describe equine Parasite Control strategies in the U.S. and evaluate to which extent respondents were in compliance with current guidelines. The study was carried out in 28 states, representing 70.9% of all equine operations with at least five equids present. Two questionnaires were administered, either by mail or delivered in person by veterinary medical officers. Participants provided specific details of their operation and were asked questions about strategies for anthelmintic therapy and diagnostic testing. A total of 380 operations provided data regarding their Parasite Control practices. Most respondents dewormed 2–3 times a year with ivermectin being the most commonly used anthelmintic. About 22% of respondents used fecal egg counts (FEC) in some form, with less than 10% using them on a regular basis. Less than 5% made use of fecal egg count reduction tests (FECRT). These results suggest little change since the last nationwide survey was conducted in 1998, as the majority of respondents did not report using FECs. This is in stark contrast to recent European surveys, where 50–60% of respondents were using FECs routinely. However, the anthelmintic treatment intensity appears to have been lowered compared to 1998. Taken together, these results suggest a continuing need for education and outreach regarding sustainable Parasite Control.
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Dynamics of Parascaris and Strongylus spp. Parasites in untreated juvenile horses.
Veterinary parasitology, 2016Co-Authors: J.v. Fabiani, Martin K. NielsenAbstract:Abstract Parasite Control in foals is of utmost importance due to the high susceptibility to parasitic infection and disease in this age group. Foals are commonly co-infected with strongyle and ascarid Parasites, which complicate Parasite Control strategies. The present study retrospectively investigated necropsy records of foals born into a university herd kept without anthelmintic treatment since 1979. The aims were to statistically analyze the relationship between fecal egg counts, worm burdens, foal age, sex, and season with specific focus on Parascaris and Strongylus spp. A total of 83 foals born between 1999 and 2015 were included. Foals were born between January and September within the given year and age at necropsy ranged between 27 and 563 days of age with a mean and median of 202 and 204 days, respectively. One set of multivariate mixed linear models was constructed analyzing strongyle and ascarid fecal egg counts as outcome variables, and another set of analyses investigated the following worm counts as outcome variables: Intestinal Parascaris spp. counts (immatures and adults), S. vulgaris (migrating and intestinal stages), S. edentatus (migrating and intestinal stages). Both ascarid and strongyle egg counts were influenced significantly by differences between study years (p Parascaris spp. (p = 0.034) and adult S. edentatus counts (p = 0.028). Larval counts of S. edentatus were significantly associated with birth month (p = 0.023), whereas counts of migrating S. vulgaris larvae were not statistically associated with any of the investigated covariates. This study provides novel information on the dynamics of important Parasites in naturally infected foals.
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equine Parasite Control under prescription only conditions in denmark awareness knowledge perception and strategies applied
Veterinary Parasitology, 2014Co-Authors: Martin K. Nielsen, Ray M. Kaplan, D C K Van Doorn, Kurt Pfister, Martin Reist, A M BecherAbstract:Due to widespread development of anthelmintic resistance in equine Parasites, recommendations for their Control are currently undergoing marked changes with a shift of emphasis toward more coprological surveillance and reduced treatment intensity. Denmark was the first nation to introduce prescription-only restrictions of anthelmintic drugs in 1999, but other European countries have implemented similar legislations over recent years. A questionnaire survey was performed in 2008 among Danish horse owners to provide a current status of practices and perceptions with relation to Parasite Control. Questions aimed at describing the current use of coprological surveillance and resulting anthelmintic treatment intensities, evaluating knowledge and perceptions about the importance of various attributes of Parasite Control, and assessing respondents' willingness to pay for advice and Parasite surveillance services from their veterinarians. A total of 1060 respondents completed the questionnaire. A large majority of respondents (71.9%) were familiar with the concept of selective therapy. Results illustrated that the respondents' self-evaluation of their knowledge about Parasites and their Control associated significantly with their level of interest in the topic and their type of education (P<0.0001). The large majority of respondents either dewormed their horses twice a year and/or performed two fecal egg counts per horse per year. This approach was almost equally pronounced in foals, horses aged 1-3 years old, and adult horses. The respondents rated prevention of parasitic disease and prevention of drug resistance as the most important attributes, while cost and frequent fecal testing were rated least important. Respondents' actual spending on Parasite Control per horse in the previous year correlated significantly with the amount they declared themselves willing to spend (P<0.0001). However, 44.4% declared themselves willing to pay more than what they were spending. Altogether, results indicate that respondents were generally familiar with equine Parasites and the concept of selective therapy, although there was some confusion over the terms small and large strongyles. They used a large degree of fecal surveillance in all age groups, with a majority of respondents sampling and/or treating around twice a year. Finally, respondents appeared willing to spend money on Parasite Control for their horses. It is of concern that the survey suggested that foals and young horses are treated in a manner very similar to adult horses, which is against current recommendations. Thus, the survey illustrates the importance of clear communication of guidelines for equine Parasite Control.
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selective therapy in equine Parasite Control application and limitations
Veterinary Parasitology, 2014Co-Authors: Martin K. Nielsen, Kurt Pfister, G Von SamsonhimmelstjernaAbstract:Since the 1960s equine Parasite Control has relied heavily on frequent anthelmintic treatments often applied with frequent intervals year-round. However, increasing levels of anthelmintic resistance in cyathostomins and Parascaris equorum are now forcing the equine industry to change to a more surveillance-based treatment approach to facilitate a reduction in treatment intensity. The principle of selective therapy has been implemented with success in small ruminant Parasite Control, and has also found use in horse populations. Typically, egg counts are performed from all individuals in the population, and those exceeding a predetermined cutoff threshold are treated. Several studies document the applicability of this method in populations of adult horses, where the overall cyathostomin egg shedding can be Controlled by only treating about half the horses. However, selective therapy has not been evaluated in foals and young horses, and it remains unknown whether the principle is adequate to also provide Control over other important Parasites such as tapeworms, ascarids, and large strongyles. One recent study associated selective therapy with increased occurrence of Strongylus vulgaris. Studies are needed to evaluate potential health risks associated with selective therapy, and to assess to which extent development of anthelmintic resistance can be delayed with this approach. The choice of strongyle egg count cutoff value for anthelmintic treatment is currently based more on tradition than science, and a recent publication illustrated that apparently healthy horses with egg counts below 100 eggs per gram (EPG) can harbor cyathostomin burdens in the range of 100,000 luminal worms. It remains unknown whether leaving such horses untreated constitutes a potential threat to equine health. The concept of selective therapy has merit for equine strongyle Control, but several questions remain as it has not been fully scientifically evaluated. There is a great need for new and improved methods for diagnosis and surveillance to supplement or replace the fecal egg counts, and equine health parameters need to be included in studies evaluating any Parasite Control program.
