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Burden DJ, Bartley DJ, Besier RB, Claerebout E, Elliott TP, Höglund J, Rehbein S, Torres-Acosta JFJ, Van Wyk JA, Yazwinski T. World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.): Third edition of the guideline for evaluating efficacy of anthelmintics in ruminants (bovine, ovine, caprine). Vet Parasitol 2024; 329:110187. [PMID: 38728835 DOI: 10.1016/j.vetpar.2024.110187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 04/15/2024] [Accepted: 04/15/2024] [Indexed: 05/12/2024]
Abstract
This guideline is aimed at those who are involved in the assessment of anthelmintic efficacy in ruminant livestock species (bovine, ovine and caprine). The intent is to provide a framework that can be adopted worldwide for the testing of anthelmintics in ruminants, such that studies carried out in different countries can be compared and thereby unnecessary duplication can be reduced. Recommendations are made for the selection, housing and feeding of study animals, the type of studies required, the method used to conduct those studies, the assessment of results and the standards for defining anthelmintic efficacy.
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Affiliation(s)
- D J Burden
- Duilio Veterinary Parasitology, The Vicarage, Church Lane, Churcham, Gloucester, UK.
| | - D J Bartley
- Disease Control, Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, UK
| | - R B Besier
- College of Environmental and Life Sciences, Murdoch University, Perth, WA, Australia
| | - E Claerebout
- Laboratory for Parasitology, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - T P Elliott
- Centre for Animal Research and Teaching, University of New England, Armidale, NSW, Australia
| | - J Höglund
- Section for Parasitology, Faculty of Veterinary Medicine and Animal Science, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - S Rehbein
- Boehringer Ingelheim Vetmedica GmbH, Kathrinenhof Research Center, Rohrdorf, Germany
| | - J F J Torres-Acosta
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Mérida, Yucatán, Mexico
| | - J A Van Wyk
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
| | - T Yazwinski
- University of Arkansas, Fayetteville, AR, USA
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Morrison AA, Chaudhry U, Andrews L, Melville L, Doyle SR, Sargison ND, Bartley DJ. Phenotypic and genotypic analysis of benzimidazole resistance in reciprocal genetic crosses of Haemonchus contortus. Int J Parasitol Drugs Drug Resist 2022; 18:1-11. [PMID: 34896787 PMCID: PMC8666523 DOI: 10.1016/j.ijpddr.2021.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 11/25/2021] [Accepted: 11/25/2021] [Indexed: 11/12/2022]
Abstract
Haemonchus contortus is arguably one of the most economically important and ubiquitous parasites of livestock globally and commonly involved in cases of anthelmintic resistance. Here, we performed reciprocal genetic crosses using susceptible (MHco3(ISE)) and multiple anthelmintic resistant (MHco18(UGA2004)) H. contortus isolates. Resultant admixed populations were designated MHco3/18 or MHco18/3, where the lead isolate reflects the origin of the females. Three independent filial generations were generated for each cross, which were subjected to bioassays, molecular approaches and population genetic analyses to investigate the phenotypic and genotypic inheritance of benzimidazole (BZ) resistance at each stage. A panel of microsatellite markers confirmed the success of the genetic cross as markers from both parents were seen in the F1 crosses. Egg hatch tests revealed a stark difference between the two F1 crosses with ED50 estimates for MHco18/3 being 9 times greater than those for MHco3/18. Resistance factors based on ED50 estimates ranged from 6 to 57 fold in the filial progeny compared to MHco3(ISE) parents. Molecular analysis of the F167Y and F200Y SNP markers associated with BZ resistance were analysed by pyrosequencing and MiSeq deep amplicon sequencing, which showed that MHco3/18.F1 and MHco18/3.F1 both had similar frequencies of the F200Y resistant allele (45.3% and 44.3%, respectively), whereas for F167Y, MHco18/3.F1 had a two-fold greater frequency of the resistant-allele compared to MHco3/18.F1 (18.2% and 8.8%, respectively). Comparison between pyrosequencing and MiSeq amplicon sequencing revealed that the allele frequencies derived from both methods were concordant at codon 200 (rc = 0.97), but were less comparable for codon 167 (rc = 0.55). The use of controlled reciprocal genetic crosses have revealed a potential difference in BZ resistance phenotype dependent on whether the resistant allele is paternally or maternally inherited. These findings provide new insight and prompt further investigation into the inheritance of BZ resistance in H. contortus.
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Affiliation(s)
- A A Morrison
- Disease Control, Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian, EH26 0PZ, United Kingdom
| | - U Chaudhry
- University of Edinburgh, Royal (Dick) School of Veterinary Studies, Easter Bush Veterinary Centre, Roslin, Midlothian, EH25 9RG, United Kingdom
| | - L Andrews
- Disease Control, Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian, EH26 0PZ, United Kingdom
| | - L Melville
- Disease Control, Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian, EH26 0PZ, United Kingdom
| | - S R Doyle
- Wellcome Sanger Institute, Hinxton, Cambridgshire, CB10 1SA, United Kingdom
| | - N D Sargison
- University of Edinburgh, Royal (Dick) School of Veterinary Studies, Easter Bush Veterinary Centre, Roslin, Midlothian, EH25 9RG, United Kingdom
| | - D J Bartley
- Disease Control, Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian, EH26 0PZ, United Kingdom.
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Charlier J, Bartley DJ, Sotiraki S, Martinez-Valladares M, Claerebout E, von Samson-Himmelstjerna G, Thamsborg SM, Hoste H, Morgan ER, Rinaldi L. Anthelmintic resistance in ruminants: challenges and solutions. Adv Parasitol 2022; 115:171-227. [PMID: 35249662 DOI: 10.1016/bs.apar.2021.12.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Anthelmintic resistance (AR) is a growing concern for effective parasite control in farmed ruminants globally. Combatting AR will require intensified and integrated research efforts in the development of innovative diagnostic tests to detect helminth infections and AR, sustainable anthelmintic treatment strategies and the development of complementary control approaches such as vaccination and plant-based control. It will also require a better understanding of socio-economic drivers of anthelmintic treatment decisions, in order to support a behavioural shift and develop targeted communication strategies that promote the uptake of evidence-based sustainable solutions. Here, we review the state-of-the-art in these different fields of research activity related to AR in helminths of livestock ruminants in Europe and beyond. We conclude that in the advent of new challenges and solutions emerging from continuing spread of AR and intensified research efforts, respectively, there is a strong need for transnational multi-actor initiatives. These should involve all key stakeholders to develop indicators of infection and sustainable control, set targets and promote good practices to achieve them.
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Affiliation(s)
| | - D J Bartley
- Disease Control, Moredun Research Institute, Penicuik, United Kingdom
| | - S Sotiraki
- Veterinary Research Institute, Hellenic Agricultural Organisation ELGO-DIMITRA, Thessaloniki, Greece
| | - M Martinez-Valladares
- Instituto de Ganadería de Montaña (CSIC-Universidad de León), Departamento de Sanidad Animal, León, Spain
| | - E Claerebout
- Ghent University, Faculty of Veterinary Medicine, Laboratory of Parasitology, Merelbeke, Belgium
| | - G von Samson-Himmelstjerna
- Institute for Parasitology and Tropical Veterinary Medicine, Veterinary Centre for Resistance Research, Freie Universität Berlin, Berlin, Germany
| | - S M Thamsborg
- Veterinary Parasitology, University of Copenhagen, Frederiksberg C, Denmark
| | - H Hoste
- INRAE, UMR 1225 IHAP INRAE/ENVT, Toulouse University, Toulouse, France
| | - E R Morgan
- Institute for Global Food Security, Queen's University Belfast, Belfast, United Kingdom
| | - L Rinaldi
- University of Naples Federico II, Unit of Parasitology and Parasitic Diseases, Department of Veterinary Medicine and Animal Production, CREMOPAR, Napoli, Italy.
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Charlier J, Rinaldi L, Musella V, Ploeger HW, Chartier C, Rose Vineer H, Hinney B, von Samson-Himmelstjerna G, Băcescu B, Mickiewicz M, Mateus TL, Martinez-Valladares M, Quealy S, Azaizeh H, Sekovska B, Akkari H, Petkevicius S, Hektoen L, Höglund J, Morgan ER, Bartley DJ, Claerebout E. Corrigendum to "Initial assessment of the economic burden of major parasitic helminth infections to the ruminant livestock industry in Europe" [Prev. Vet. Med. 182 (2020) 105103]. Prev Vet Med 2020; 188:105213. [PMID: 33261929 DOI: 10.1016/j.prevetmed.2020.105213] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- J Charlier
- Kreavet, H. Mertensstraat 17, 9150 Kruibeke, Belgium.
| | - L Rinaldi
- Department of Veterinary Medicine and Animal Production, CREMOPAR, University of Naples Federico II, 80137 Napoli, Italy
| | - V Musella
- Department of Health Sciences, University of Catanzaro "Magna Græcia", CISVetSUA, 88100 Catanzaro, Italy
| | - H W Ploeger
- Department of Infectious Diseases and Immunology, Clinical Infectiology Division, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands
| | - C Chartier
- INRAE, Oniris, BIOEPAR, 44307, Nantes, France
| | - H Rose Vineer
- Department of Infection Biology and Microbiomes, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst, Neston, Cheshire, CH64 7TE, UK
| | - B Hinney
- Institute of Parasitology, Department of Pathobiology, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210 Wien, Austria
| | - G von Samson-Himmelstjerna
- Freie Universität Berlin, Institute for Parasitology and Tropical Veterinary Medicine, Robert-von-Ostertag-Str. 7-13, 14163 Berlin, Germany
| | - B Băcescu
- Faculty of Veterinary Medicine, Spiru Haret University, Blv. Basarabia 256, Bucharest, Romania
| | - M Mickiewicz
- Division of Veterinary Epidemiology and Economics, Institute of Veterinary Medicine, Warsaw University of Life Sciences, Nowoursynowska 159c, 02-786 Warsaw, Poland
| | - T L Mateus
- CISAS - Center for Research and Development in Agrifood Systems and Sustainability, Escola Superior Agrária, Instituto Politécnico de Viana do Castelo, Rua Escola Industrial e Comercial Nun'Álvares, 4900-347 Viana do Castelo, Portugal; EpiUnit - Instituto de Saúde Pública da Universidade do Porto, Rua das Taipas, 135, 4050-091 Porto, Portugal
| | - M Martinez-Valladares
- Instituto de Ganadería de Montaña (CSIC-Universidad de León), Departamento de Sanidad Animal, 24236 Grulleros, León, Spain
| | - S Quealy
- VirtualVet, Grenan Upper, Kilmacthomas, Co., Waterford, Ireland
| | - H Azaizeh
- Institute of Applied Research, University of Haifa, The Galilee Society P.O. Box 437, Shefa-Amr 20200, Israel; Tel Hai College, Department of Environmental Sciences, Upper Galilee 12210, Israel
| | - B Sekovska
- Faculty of Veterinary Medicine, University St. Cyril and Methodius, Skopje, North Macedonia
| | - H Akkari
- Laboratory of Parasitology, University of Manouba, National School of Veterinary Medicine of Sidi Thabet, 2020 Sidi Thabet, Tunisia
| | - S Petkevicius
- Department of Veterinary Pathobiology, Faculty of Veterinary Medicine, Veterinary Academy, Lithuanian University of Health Sciences, Tilžės 18, LT-47181 Kaunas, Lithuania
| | - L Hektoen
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, P.O. Box 369 Sentrum, 0102 Oslo, Norway
| | - J Höglund
- Swedish University of Agricultural Sciences, Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, P.O. Box 7036, SE-750 07 Uppsala, Sweden
| | - E R Morgan
- Institute for Global Food Security, Queen's University Belfast, 19, Chlorine Gardens, Belfast, BT9 5DL, UK
| | - D J Bartley
- Disease Control, Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, EH26 0PZ, UK
| | - E Claerebout
- Ghent University, Faculty of Veterinary Medicine, Laboratory of Parasitology, Salisburylaan 133, 9820 Merelbeke, Belgium
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Charlier J, Rinaldi L, Musella V, Ploeger HW, Chartier C, Vineer HR, Hinney B, von Samson-Himmelstjerna G, Băcescu B, Mickiewicz M, Mateus TL, Martinez-Valladares M, Quealy S, Azaizeh H, Sekovska B, Akkari H, Petkevicius S, Hektoen L, Höglund J, Morgan ER, Bartley DJ, Claerebout E. Initial assessment of the economic burden of major parasitic helminth infections to the ruminant livestock industry in Europe. Prev Vet Med 2020; 182:105103. [PMID: 32750638 DOI: 10.1016/j.prevetmed.2020.105103] [Citation(s) in RCA: 147] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 06/29/2020] [Accepted: 07/23/2020] [Indexed: 01/16/2023]
Abstract
We report a European wide assessment of the economic burden of gastrointestinal nematodes, Fasciola hepatica (common liver fluke) and Dictyocaulus viviparus (bovine lungworm) infections to the ruminant livestock industry. The economic impact of these parasitic helminth infections was estimated by a deterministic spreadsheet model as a function of the proportion of the ruminant population exposed to grazing, the infection frequency and intensity, the effect of the infection on animal productivity and mortality and anthelmintic treatment costs. In addition, we estimated the costs of anthelmintic resistant nematode infections and collected information on public research budgets addressing helminth infections in ruminant livestock. The epidemiologic and economic input data were collected from international databases and via expert opinion of the Working Group members of the European Co-operation in Science and Technology (COST) action COMbatting Anthelmintic Resistance in ruminants (COMBAR). In order to reflect the effects of uncertainty in the input data, low and high cost estimates were obtained by varying uncertain input data arbitrarily in both directions by 20 %. The combined annual cost [low estimate-high estimate] of the three helminth infections in 18 participating countries was estimated at € 1.8 billion [€ 1.0-2.7 billion]. Eighty-one percent of this cost was due to lost production and 19 % was attributed to treatment costs. The cost of gastrointestinal nematode infections with resistance against macrocyclic lactones was estimated to be € 38 million [€ 11-87 million] annually. The annual estimated costs of helminth infections per sector were € 941 million [€ 488 - 1442 million] in dairy cattle, € 423 million [€ 205-663 million] in beef cattle, € 151million [€ 90-213 million] in dairy sheep, € 206 million [€ 132-248 million] in meat sheep and € 86 million [€ 67-107 million] in dairy goats. Important data gaps were present in all phases of the calculations which lead to large uncertainties around the estimates. Accessibility of more granular animal population datasets at EU level, deeper knowledge of the effects of infection on production, levels of infection and livestock grazing exposure across Europe would make the largest contribution to improved burden assessments. The known current public investment in research on helminth control was 0.15 % of the estimated annual costs for the considered parasitic diseases. Our data suggest that the costs of enzootic helminth infections which usually occur at high prevalence annually in ruminants, are similar or higher than reported costs of epizootic diseases. Our data can support decision making in research and policy to mitigate the negative impacts of helminth infections and anthelmintic resistance in Europe, and provide a baseline against which to measure future changes.
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Affiliation(s)
- J Charlier
- Kreavet, H. Mertensstraat 17, 9150, Kruibeke, Belgium.
| | - L Rinaldi
- Department of Veterinary Medicine and Animal Production, CREMOPAR, University of Naples Federico II, 80137, Napoli, Italy
| | - V Musella
- Department of Health Sciences, University of Catanzaro "Magna Græcia", CISVetSUA, 88100, Catanzaro, Italy
| | - H W Ploeger
- Department of Infectious Diseases and Immunology, Clinical Infectiology Division, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL, Utrecht, the Netherlands
| | - C Chartier
- INRAE, Oniris, BIOEPAR, 44307, Nantes, France
| | - H Rose Vineer
- Department of Infection Biology and Microbiomes, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst, Neston, Cheshire, CH64 7TE, UK
| | - B Hinney
- Institute of Parasitology, Department of Pathobiology, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210, Wien, Austria
| | - G von Samson-Himmelstjerna
- Freie Universität Berlin, Institute for Parasitology and Tropical Veterinary Medicine, Robert-von-Ostertag-Str. 7-13, 14163, Berlin, Germany
| | - B Băcescu
- Faculty of Veterinary Medicine, Spiru Haret University, Blv. Basarabia 256, Bucharest, Romania
| | - M Mickiewicz
- Division of Veterinary Epidemiology and Economics, Institute of Veterinary Medicine, Warsaw University of Life Sciences, Nowoursynowska 159c, 02-786, Warsaw, Poland
| | - T L Mateus
- CISAS - Center for Research and Development in Agrifood Systems and Sustainability, Escola Superior Agrária, Instituto Politécnico de Viana do Castelo, Rua Escola Industrial e Comercial Nun'Álvares, 4900-347, Viana do Castelo, Portugal; EpiUnit - Instituto de Saúde Pública da Universidade do Porto, Rua das Taipas, 135, 4050-091, Porto, Portugal
| | - M Martinez-Valladares
- Instituto de Ganadería de Montaña (CSIC-Universidad de León), Departamento de Sanidad Animal. 24236, Grulleros, León, Spain
| | - S Quealy
- VirtualVet, Grenan Upper, Kilmacthomas, Co. Waterford, Ireland
| | - H Azaizeh
- Institute of Applied Research, University of Haifa, The Galilee Society, Israel & Tel Hai College, Department of Environmental Sciences, Upper Galilee 12210, P.O. Box 437, Shefa-Amr, 20200, Israel
| | - B Sekovska
- Faculty of Veterinary Medicine, University St. Cyril and Methodius, Skopje, Macedonia
| | - H Akkari
- Laboratory of Parasitology, University of Manouba, National School of Veterinary Medicine of Sidi Thabet, 2020, Sidi Thabet, Tunisia
| | - S Petkevicius
- Department of Veterinary Pathobiology, Faculty of Veterinary Medicine, Veterinary Academy, Lithuanian University of Health Sciences, Tilžės 18, LT-47181, Kaunas, Lithuania
| | - L Hektoen
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, P.O.Box 369 Sentrum, 0102, Oslo, Norway
| | - J Höglund
- Swedish University of Agricultural Sciences, Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, P.O. Box 7036, SE-750 07, Uppsala, Sweden
| | - E R Morgan
- Institute for Global Food Security, Queen's University Belfast, 19, Chlorine Gardens, Belfast, BT9 5DL, UK
| | - D J Bartley
- Disease Control, Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, EH26 0PZ, UK
| | - E Claerebout
- Ghent University, Faculty of Veterinary Medicine, Laboratory of Parasitology, Salisburylaan 133, 9820, Merelbeke, Belgium
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Charlier J, Thamsborg SM, Bartley DJ, Skuce PJ, Kenyon F, Geurden T, Hoste H, Williams AR, Sotiraki S, Höglund J, Chartier C, Geldhof P, van Dijk J, Rinaldi L, Morgan ER, von Samson-Himmelstjerna G, Vercruysse J, Claerebout E. Mind the gaps in research on the control of gastrointestinal nematodes of farmed ruminants and pigs. Transbound Emerg Dis 2017; 65 Suppl 1:217-234. [PMID: 29124904 DOI: 10.1111/tbed.12707] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Indexed: 12/31/2022]
Abstract
Gastrointestinal (GI) nematode control has an important role to play in increasing livestock production from a limited natural resource base and to improve animal health and welfare. In this synthetic review, we identify key research priorities for GI nematode control in farmed ruminants and pigs, to support the development of roadmaps and strategic research agendas by governments, industry and policymakers. These priorities were derived from the DISCONTOOLS gap analysis for nematodes and follow-up discussions within the recently formed Livestock Helminth Research Alliance (LiHRA). In the face of ongoing spread of anthelmintic resistance (AR), we are increasingly faced with a failure of existing control methods against GI nematodes. Effective vaccines against GI nematodes are generally not available, and anthelmintic treatment will therefore remain a cornerstone for their effective control. At the same time, consumers and producers are increasingly concerned with environmental issues associated with chemical parasite control. To address current challenges in GI nematode control, it is crucial to deepen our insights into diverse aspects of epidemiology, AR, host immune mechanisms and the socio-psychological aspects of nematode control. This will enhance the development, and subsequent uptake, of the new diagnostics, vaccines, pharma-/nutraceuticals, control methods and decision support tools required to respond to the spread of AR and the shifting epidemiology of GI nematodes in response to climatic, land-use and farm husbandry changes. More emphasis needs to be placed on the upfront evaluation of the economic value of these innovations as well as the socio-psychological aspects to prioritize research and facilitate uptake of innovations in practice. Finally, targeted regulatory guidance is needed to create an innovation-supportive environment for industries and to accelerate the access to market of new control tools.
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Affiliation(s)
- J Charlier
- Kreavet, Kruibeke, Belgium.,Avia-GIS, Zoersel, Belgium
| | - S M Thamsborg
- Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg C, Denmark
| | | | - P J Skuce
- Moredun Research Institute, Edinburgh, UK
| | - F Kenyon
- Moredun Research Institute, Edinburgh, UK
| | | | - H Hoste
- UMR IHAP 1225, INRA, ENVT, Université de Toulouse, Toulouse, France
| | - A R Williams
- Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg C, Denmark
| | - S Sotiraki
- VetResInst, HAO-DEMETER, Thessaloniki, Greece
| | - J Höglund
- BVF, Section for Parasitology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | | | - P Geldhof
- Laboratory of Parasitology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - J van Dijk
- Institute of Infection and Global Health, University of Liverpool, Neston, Cheshire, UK
| | - L Rinaldi
- Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, Napoli, Italy
| | - E R Morgan
- Institute for Global Food Security, Queen's University Belfast, Belfast, UK.,School of Veterinary Science, University of Bristol, North Somerset, UK
| | | | - J Vercruysse
- Laboratory of Parasitology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - E Claerebout
- Laboratory of Parasitology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
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Bartley DJ, Meslé M, Donegan H, Devin L, Morrison AA. Phenotypic assessment of the ovicidal activity of monepantel and monepantel sulfone on gastro-intestinal nematode eggs. Vet Parasitol 2016; 220:87-92. [PMID: 26995727 DOI: 10.1016/j.vetpar.2016.02.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 02/11/2016] [Accepted: 02/20/2016] [Indexed: 11/29/2022]
Abstract
The in vitro ovicidal activity of the amino acetonitrile derivative, monepantel (MPTL) and its active metabolite monepantel sulfone (MPTL-SO2) were assessed against a number of commercially important nematode species of ruminants, namely Teladorsagia circumcincta, Haemonchus contortus and Trichostrongylus axei. An egg hatch test (EHT) was used to make the assessment of both drug sensitive and drug resistant isolates. Both MPTL and MPTL-SO2 showed moderate ovicidal activity in vitro against all of the species examined, although species specific differences as measured by inhibitory concentration were observed. Analysis of the drug sensitive isolates showed H. contortus to be the most sensitive to both MPTL and MPTL-SO2 (ED50 1.7 and 2.7 μg/ml respectively) followed by T. circumcincta (ED50 2.1 and 2.7 μg/ml respectively) followed by T. axei (ED50 68.7 and 60.1 μg/ml respectively). Overall the EHT results would suggest no "global" in vitro discriminatory dose for detection of MPTL resistance is likely to be achievable, using the egg hatch test, due to large inherent variability observed between species. The test identified a dose dependent increase in MPTL and MPTL-SO2 sensitivity in two MPTL resistant T. circumcincta isolates and therefore offers to be a promising tool for the phenotypic characterisation of MPTL sensitivity, allowing exploration into the mechanisms involved in selection and development of MPTL resistance.
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Affiliation(s)
- D J Bartley
- Department of Disease Control, Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, United Kingdom.
| | - M Meslé
- Department of Disease Control, Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, United Kingdom.
| | - H Donegan
- Department of Disease Control, Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, United Kingdom.
| | - L Devin
- Department of Disease Control, Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, United Kingdom.
| | - A A Morrison
- Department of Disease Control, Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, United Kingdom.
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Lester HE, Bartley DJ, Morgan ER, Hodgkinson JE, Stratford CH, Matthews JB. A cost comparison of faecal egg count-directed anthelmintic delivery versus interval programme treatments in horses. Vet Rec 2013; 173:371. [PMID: 24068698 DOI: 10.1136/vr.101804] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- H E Lester
- Department of Disease Control, Moredun Research Institute, Edinburgh EH26 0PZ, UK
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McMahon C, Bartley DJ, Edgar HWJ, Ellison SE, Barley JP, Malone FE, Hanna REB, Brennan GP, Fairweather I. Anthelmintic resistance in Northern Ireland (I): prevalence of resistance in ovine gastrointestinal nematodes, as determined through faecal egg count reduction testing. Vet Parasitol 2013; 195:122-30. [PMID: 23398988 DOI: 10.1016/j.vetpar.2013.01.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 01/06/2013] [Accepted: 01/13/2013] [Indexed: 11/16/2022]
Abstract
The prevalence of anthelmintic resistance in Northern Ireland sheep flocks was evaluated between July and October 2011. Sampling kits were sent to 172 flock owners and returns were received from 91. Within this survey population, 27 flock owners used benzimidazole products, 10 used levamisole products, 15 used avermectin products, 26 used milbemycin products and 4 flock owners used the amino acetonitrile derivative, Monepantel. The remaining 9 flock owners used combination drenches (broad spectrum wormer plus fasciolicide). However, 15 sets of samples were ineligible for faecal egg count reduction testing due to either too low an egg count or insufficient faecal volume. Treatment efficacy below 95%, indicating significant resistance, was detected in 81% (n=24) of flocks tested for benzimidazole resistance; in 14% (n=1) of flocks tested for levamisole resistance; and in 50% (n=7) and 62% (n=13) of flocks tested for avermectin and milbemycin resistance, respectively. Monepantel resistance was absent in all (n=3) flocks tested. Combination products (broad spectrum nematocide plus flukicide) containing levamisole were entirely effective, while treatment efficacy below 95% was detected in 60% (n=3) of flocks where the nematocide in the combination product was a benzimidazole. Where parasite identification based on coproculture was completed, Trichostrongylus was the dominant genus detected in all cases post-treatment, indicating the occurrence of anthelmintic-resistant Trichostrongylus spp. populations. Benzimidazole efficacy was highest in treating Trichostrongylus spp. (51%) and lowest when treating Teladorsagia spp. Levamisole was 100% effective in treating Cooperia, but ineffective (0%) in treating Trichostrongylus spp. Avermectin efficacy was highest when treating Haemonchus contortus (100%) and Teladorsagia spp. (73%), with a marginally lower efficacy against Trichostrongylus spp. (71%). Moxidectin efficacy was 33% against Trichostrongylus spp., 68% against Teladorsagia spp., 97% against Cooperia spp. and 100% against Haemonchus contortus infections.
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Affiliation(s)
- C McMahon
- Parasite Therapeutics Research Group, School of Biological Sciences, Medical Biology Centre, The Queen's University of Belfast, 97 Lisburn Road, Belfast, BT9 7BL, United Kingdom
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McArthur CL, Bartley DJ, Shaw DJ, Matthews JB. Assessment of ivermectin efficacy against gastrointestinal nematodes in cattle on four Scottish farms. Vet Rec 2011; 169:658. [DOI: 10.1136/vr.100084] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- C. L. McArthur
- Moredun Research Institute; Pentlands Science Park, Bush Loan Penicuik Midlothian EH26 0PZ UK
| | - D. J. Bartley
- Moredun Research Institute; Pentlands Science Park, Bush Loan Penicuik Midlothian EH26 0PZ UK
| | - D. J. Shaw
- Royal (Dick) School of Veterinary Studies and Roslin Institute; University of Edinburgh; Midlothian EH25 9RG UK
| | - J. B. Matthews
- Moredun Research Institute; Pentlands Science Park, Bush Loan Penicuik Midlothian EH26 0PZ UK
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11
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Affiliation(s)
- N. D. Sargison
- Royal (Dick) School of Veterinary Studies; University of Edinburgh, Large Animal Practice; Easter Bush Veterinary Centre; Roslin Midlothian EH25 9RG
| | - D. J. Wilson
- Royal (Dick) School of Veterinary Studies; University of Edinburgh, Large Animal Practice; Easter Bush Veterinary Centre; Roslin Midlothian EH25 9RG
| | - C. D. Penny
- Royal (Dick) School of Veterinary Studies; University of Edinburgh, Large Animal Practice; Easter Bush Veterinary Centre; Roslin Midlothian EH25 9RG
| | - D. J. Bartley
- Moredun Research Institute; Pentlands Science Park, Bush Loan Penicuik Midlothian EH26 0PZ
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Sargison ND, Jackson F, Wilson DJ, Bartley DJ, Penny CD, Gilleard JS. Characterisation of milbemycin-, avermectin-, imidazothiazole- and benzimidazole-resistant Teladorsagia circumcincta
from a sheep flock. Vet Rec 2010; 166:681-6. [DOI: 10.1136/vr.b4853] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- N. D. Sargison
- Large Animal Practice; Royal (Dick) School of Veterinary Studies; University of Edinburgh; Easter Bush Veterinary Centre; Roslin Midlothian EH25 9RG
| | - F. Jackson
- Department of Parasitology; Moredun Research Institute; Pentlands Science Park, Bush Loan Penicuik Midlothian EH26 0PZ
| | - D. J. Wilson
- Large Animal Practice; Royal (Dick) School of Veterinary Studies; University of Edinburgh; Easter Bush Veterinary Centre; Roslin Midlothian EH25 9RG
| | - D. J. Bartley
- Department of Parasitology; Moredun Research Institute; Pentlands Science Park, Bush Loan Penicuik Midlothian EH26 0PZ
| | - C. D. Penny
- Large Animal Practice; Royal (Dick) School of Veterinary Studies; University of Edinburgh; Easter Bush Veterinary Centre; Roslin Midlothian EH25 9RG
| | - J. S. Gilleard
- Department of Comparative Biology and Experimental Medicine; Faculty of Veterinary Medicine; University of Calgary; 3330 Hospital Drive NW Calgary Alberta Canada
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Sargison ND, Wilson DJ, Bartley DJ, Penny CD, Jackson F. Haemonchosis and teladorsagiosis in a Scottish sheep flock putatively associated with the overwintering of hypobiotic fourth stage larvae. Vet Parasitol 2007; 147:326-31. [PMID: 17531390 DOI: 10.1016/j.vetpar.2007.04.011] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2006] [Revised: 04/03/2007] [Accepted: 04/19/2007] [Indexed: 11/23/2022]
Abstract
The cause of ill thrift and deaths was investigated in a group of 40 Scottish lowground ewes, which had been treated with levamisole and then turned onto clean grazing after lambing, 6-8 weeks previously. Concurrent haemonchosis and teladorsagiosis were diagnosed, putatively associated with the spring maturation of large numbers of hypobiotic larvae. Ill thrift due to parasitic gastroenteritis consequently occurred in the lambs which had been turned onto the 'clean' grazing with their dams, despite metaphylactic anthelmintic treatments. The contributory role of haemonchosis resulting in serious production-limiting disease is unusual in Scottish sheep flocks. It is suggested that the problem may have arisen as a consequence of the adaptation of Haemonchus contortus to survive overwinter in a cold climate as arrested early fourth stage larvae, which were not eliminated when the ewes were treated with levamisole at turnout.
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Affiliation(s)
- N D Sargison
- Royal (Dick) School of Veterinary Studies, Large Animal Practice, Easter Bush Veterinary Centre, Roslin, Midlothian, Scotland EH25 9RG, UK.
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Sargison ND, Jackson F, Bartley DJ, Wilson DJ, Stenhouse LJ, Penny CD. Observations on the emergence of multiple anthelmintic resistance in sheep flocks in the south-east of Scotland. Vet Parasitol 2006; 145:65-76. [PMID: 17134836 DOI: 10.1016/j.vetpar.2006.10.024] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2006] [Revised: 10/25/2006] [Accepted: 10/30/2006] [Indexed: 11/17/2022]
Abstract
Multiple resistance to benzimidazole, imidazothiazole and macrocyclic lactone anthelmintics is an emerging problem in the south-east of Scotland. The general management and nematode control strategies employed in four affected flocks (flocks 1-4) were investigated in an attempt to identify the risk factors which might have led to the appearance of production limiting disease associated with anthelmintic resistance. The important risk factors for multiple anthelmintic resistance could not be confirmed and it proved easier to criticise nematode control practices on theoretical grounds, than to propose practical solutions. It seems likely that different risk factors were involved in the four flocks. Lambs in flocks 1 and 2 had been treated with an anthelmintic at 3-4 weekly intervals with the aim of achieving suppressive nematode control, while sheep in flock 1 had been treated with an anthelmintic after they were moved onto clean grazing. Recently lambed ewes had been treated with moxidectin in three of the four flocks, with the aim of controlling their periparturient rise in faecal nematode egg output. All of these factors might have contributed to the emergence of multiple anthelmintic resistance, because they could have led to anthelmintic treatments at times when the nematode population in refugia was small, compared to that in the sheep. Annual rotation of the anthelmintic group was compromised by the emergence of benzimidazole resistance and did not prevent the emergence of multiple resistance in any of the flocks described, although the practice may have slowed the development of resistance. Underdosing may have selected for benzimidazole and imidazothiazole resistance in flock 2, associated with inaccurate estimation of the weights of terminal sire lambs. These investigations also highlighted problems associated with the diagnosis of anthelmintic resistance, in particular the confounding effects of the onset of host immunity to nematode parasites, the possible influence of the age of the adult nematode population, and the insensitivity of the undifferentiated faecal egg count reduction test in situations where resistance is emerging.
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Affiliation(s)
- N D Sargison
- Royal (Dick) School of Veterinary Studies, Large Animal Practice, Easter Bush Veterinary Centre, Roslin, Midlothian, UK.
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Bartley DJ, Donnan AA, Jackson E, Sargison N, Mitchell GBB, Jackson F. A small scale survey of ivermectin resistance in sheep nematodes using the faecal egg count reduction test on samples collected from Scottish sheep. Vet Parasitol 2006; 137:112-8. [PMID: 16426761 DOI: 10.1016/j.vetpar.2005.12.014] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2005] [Revised: 12/07/2005] [Accepted: 12/13/2005] [Indexed: 10/25/2022]
Abstract
Thirty-eight sheep flocks, predominantly from the south/central Scotland, were examined using a faecal egg count reduction test (FECRT) for the presence of ivermectin (IVM) resistant nematodes. Efficacies of less than 95%, 14-17 days post-treatment, were identified in 6 of 17 naturally grazing flocks where pre-treatment faecal egg counts were in excess of 150 eggs per gram. Efficacies on these IVM resistant farms ranged from 66 to 92%. One other suspected cases of IVM resistance was also identified in returned material. The larvae detected in post-treatment coprocultures from resistant flocks were from the genera Teladorsagia (4 from 6) and Trichostrongylus (2 from 6).
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Affiliation(s)
- D J Bartley
- Department of Parasitology, Moredun Research Institute, Pentland Science Park, Bush Loan, Penicuik EH26 0PZ, UK.
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Bartley DJ, Jackson E, Sargison N, Jackson F. Further characterisation of a triple resistant field isolate of Teladorsagia from a Scottish lowland sheep farm. Vet Parasitol 2005; 134:261-6. [PMID: 16168563 DOI: 10.1016/j.vetpar.2005.07.017] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2005] [Revised: 06/22/2005] [Accepted: 07/21/2005] [Indexed: 11/23/2022]
Abstract
Anthelmintic efficacies against juvenile developing populations of Teladorsagia species that were known to be resistant to anthelmintics from all three broad spectrum families were examined using a controlled efficacy test. Fenbendazole (FBZ), levamisole (LEV), ivermectin (IVM), combinations of these anthelmintics and moxidectin (MOX) were assessed in parasite naïve lambs artificially infected with 8,000 third stage larvae (Tci5) and treated orally 8-day post-infection with the compounds at the manufacturers recommended dose rates, FBZ, 5 mg/kg body weight (BW); LEV, 7.5 mg/kg BW; IVM, 0.2 mg/kg BW; MOX (0.2 mg/kg BW). The lambs were slaughtered 14-day post-treatment. The arithmetic mean worm burden reductions resulting from oral treatments with FBZ; IVM; LEV; FBZ+IVM; FBZ+LEV; FBZ, LEV+IVM or MOX were 36%, 82%, 38%, 86%, 60%, 88% and 97%, respectively. The results illustrate that combination treatments showed improved efficacies against the juvenile population compared to individually administered treatments but that these improvements were not wholly effective. Moxidectin was the only treatment that was over 95% effective, though caution should be noted when advising the use of MOX prophylactically since 3% of the infection still survived this treatment. Treatments directed at juvenile stages of Tci5 were less effective, with the exception of IVM, compared to a similar trial using Tci5 where the same treatments were directed against a predominantly adult population. No interaction was detected comparing the timings of treatments and its effectiveness with the exception of IVM (two-way ANOVA, p < 0.05). These findings suggest that, on the whole, the selection processes for anthelmintic resistance (AR) may occur at an early stage of development within the parasites, having severe implications for the early detection of AR.
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Affiliation(s)
- D J Bartley
- Department of Parasitology, Moredun Research Institute, Pentland Science Park, Bush Loan, Penicuik EH26 0PZ, UK.
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Sargison ND, Jackson F, Bartley DJ, Moir ACP. Failure of moxidectin to control benzimidazole–, levamisole– and ivermectinresistant
Teladorsagia circumcincta
in a sheep flock. Vet Rec 2005; 156:105-9. [PMID: 15704550 DOI: 10.1136/vr.156.4.105] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Control of a benzimidazole-, levamisole- and ivermectin-resistant population of Teladorsagia circumcincta was attempted using moxidectin administered orally at the manufacturer's recommended dose rate of 200 microg/kg bodyweight. Ewes were dosed after lambing with the aim of controlling their periparturient rise in faecal egg output and lambs were dosed at six-week intervals throughout the summer. This regimen failed to suppress the establishment of significant numbers of infective helminth larvae on the pasture, resulting in unsatisfactory lamb production. Oral dosing with moxidectin was effective in removing adult female burdens of ivermectin-resistant T. circumcincta, but the effect of the drug did not persist against the resistant helminth population.
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Affiliation(s)
- N D Sargison
- Large Animal Practice, Royal (Dick) School of Veterinary Studies, Easter Bush Veterinary Centre, Roslin, Midlothian
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Jackson F, Greer AW, Huntley J, McAnulty RW, Bartley DJ, Stanley A, Stenhouse L, Stankiewicz M, Sykes AR. Studies using Teladorsagia circumcincta in an in vitro direct challenge method using abomasal tissue explants. Vet Parasitol 2004; 124:73-89. [PMID: 15350663 DOI: 10.1016/j.vetpar.2004.06.025] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2003] [Revised: 05/05/2004] [Accepted: 06/16/2004] [Indexed: 11/20/2022]
Abstract
An in vitro direct challenge (IVDC) method in which abomasal tissue explants maintained at 37 degrees C in Hanks/Hepes solution (pH 7.6) in a high oxygen concentration (incubator gassed with pure oxygen and sealed prior to use) were-challenged with exsheathed third stage larvae of Teladorsagia circumcincta has been used to investigate the tissue association phase of larval establishment. Studies using naïve and recently challenged immune sheep and goat abomasal tissues have shown significant reductions (P < 0.05) in the numbers of tissue associated larvae in material from immune animals. The mechanisms that affect the tissue association process appear to be labile since more larvae were recovered from the tissue digests of previously infected sheep that had not been recently exposed to larval challenge in comparison to those that had been recently challenged (P < 0.05). The method has also been used to demonstrate the influence of protein nutrition on the establishment of larvae in abomasal tissues and region specific differences in the efficacy of exclusion mechanisms. The technique appears to have potential as a means of investigating the crucial first phase of the process of establishment.
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Affiliation(s)
- F Jackson
- Department of Parasitology, Moredun Research Institute, Pentland Science Park, Bush Loan, Penicuik EH26 0PZ, UK.
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Bartley DJ, Jackson F, Jackson E, Sargison N. Characterisation of two triple resistant field isolates of Teladorsagia from Scottish lowland sheep farms. Vet Parasitol 2004; 123:189-99. [PMID: 15325045 DOI: 10.1016/j.vetpar.2004.06.018] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2003] [Revised: 05/28/2004] [Accepted: 06/04/2004] [Indexed: 11/21/2022]
Abstract
The anthelmintic resistance status of two field isolates derived from farms (farm A and B) located near Edinburgh were examined using both controlled efficacy tests (CET) and faecal egg count reduction tests (FECRT). Efficacies against fenbendazole (FBZ), levamisole (LEV) and ivermectin (IVM) and, for one isolate, against combinations of these anthelmintics and moxidectin were determined in naïve lambs, artificially infected with the isolates and treated with the compounds at the manufacturers recommended dose rates. (FBZ, 5mg/kg bodyweight (BW); LEV, 7.5mg/kg BW; IVM, 0.2mg/kg BW; Moxidectin (MOX) 0.2mg/kg BW). In both field isolates, the predominant species found pre-treatment and the only species found post-treatment was Teladorsagia circumcincta. Resistance to FBZ, LEV and IVM was confirmed in CET and FECRT on farm A and to the latter two compounds on farm B, which had a history of benzimidazole resistance and where TBZ resistance was also demonstrated using an egg hatch assay (EHA). For the farm A isolate CET efficacies against FBZ; IVM; LEV; FBZ + IVM; FBZ + LEV; FBZ, LEV + IVM and MOX were 59, 60, 88, 94,93, 92 and 98%, respectively. The CET efficacies for the farm B isolate were 51% and 72% for LEV and IVM, respectively.
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Affiliation(s)
- D J Bartley
- Department of Parasitology, Moredun Research Institute, Pentland Science Park, Bush Loan, Penicuik EH26 0PZ, UK.
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