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Home / Equine Research Bank / Int J Parasitol Drugs Drug Resist / Anthelmintic resistance in equine nematodes.
International journal for parasitology. Drugs and drug resistance2014; 4(3); 310-315; doi: 10.1016/j.ijpddr.2014.10.003

Anthelmintic resistance in equine nematodes.

Abstract: Anthelmintics have been applied indiscriminately to control horse nematodes for over 40 years. Three broad-spectrum anthelmintic classes are currently registered for nematode control in horses: benzimidazoles (fenbendazole, oxibendazole), tetrahydropyrimidines (pyrantel) and macrocyclic lactones (ivermectin, moxidectin). Generally, control strategies have focused on nematode egg suppression regimens that involve the frequent application of anthelmintics to all horses at intervals based on strongyle egg reappearance periods after treatment. The widespread use of such programmes has substantially reduced clinical disease, especially that associated with large strongyle species; however, high treatment frequency has led to considerable selection pressure for anthelmintic resistance, particularly in cyathostomin species. Field studies published over the last decade indicate that benzimidazole resistance is widespread globally in cyathostomins and there are also many reports of resistance to pyrantel in these worms. Cyathostomin resistance to macrocyclic lactone compounds is emerging, principally measured as a reduction in strongyle egg reappearance time observed after treatment. Ivermectin resistance is a further concern in the small intestinal nematode, Parascaris equorum, an important pathogen of foals. These issues indicate that horse nematodes must now be controlled using methods less dependent on anthelmintic use and more reliant on management practices designed to reduce the force of infection in the environment. Such strategies include improved grazing management integrated with targeted anthelmintic administration involving faecal egg count (FEC)-directed treatments. The latter require that the supporting diagnostic tests available are robust and practically applicable. Recent research has focused on maximising the value of FEC analysis in horses and on optimizing protocols for anthelmintic efficacy testing. Other studies have sought to develop diagnostics that will help define levels of pre-patent infection. This review describes recent advances in each of these areas of research.
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Publication Date: 2014-10-25 PubMed ID: 25516842PubMed Central: PMC4266799DOI: 10.1016/j.ijpddr.2014.10.003Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research paper discusses the development of resistance to anthelmintics, a type of drug used to control parasitic nematodes, in horses due to their indiscriminate use over the past 40 years. The authors suggest alternative control methods focused more on management practices and less on drug use, including targeted administration based on faecal egg count analysis and robust diagnostic testing.

Indiscriminate Use of Anthelmintics

  • The authors begin by discussing the common practice of indiscriminate anthelmintic use to control horse nematodes for over four decades.
  • Three broad categories of these drugs – benzimidazoles, tetrahydropyrimidines, and macrocyclic lactones – are currently recognized for nematode control in horses.
  • Traditionally, control strategies have been primarily focused on nematode egg suppression, which carries out frequent application of anthelmintics to all horses based on specific reproductive cycles of the nematodes.

The Consequences of Overuse and Emerging Resistance

  • The extensive use of these controls has significantly reduced clinical diseases, particularly those associated with large strongyle species.
  • Despite these benefits, the high frequency of treatments has led to considerable selection pressure, resulting in greater anthelmintic resistance, specifically in cyathostomin species.
  • Recent field studies indicate that resistance to benzimidazoles is globally widespread in cyathostomins.
  • The paper also mentions increasing reports of resistance to pyrantel in these worms.
  • Further, there are signs of cyathostomin resistance to macrocyclic lactone compounds. This resistance is primarily measurable as a shortened strongyle egg reappearance time following treatment.
  • The authors express concern about ivermectin resistance in the small intestinal nematode, Parascaris equorum, which is an important pathogen in foals.

Alternative Methods for Nematode Control in Horses

  • Given the issues discussed above, the paper emphasizes the need for changes in nematode control strategies.
  • New control methods should primarily comprise management practices reducing infection transmission rather than basing control on anthelmintic use.
  • These practices could include enhanced grazing management combined with targeted anthelmintic administration such as faecal egg count (FEC)-directed treatments.
  • The authors highlight the need for robust and practical diagnostic tests to support these targeted treatments.
  • The paper also recognizes recent research aimed at improving FEC analysis and optimizing anthelmintic efficacy testing protocols.
  • Other studies are focused on the development of diagnostics to help identify levels of pre-patent infection.
  • Lastly, the authors provide an overview of recent advancements in these areas of research.

Cite This Article

APA
Matthews JB. (2014). Anthelmintic resistance in equine nematodes. Int J Parasitol Drugs Drug Resist, 4(3), 310-315. https://doi.org/10.1016/j.ijpddr.2014.10.003

Publication

International journal for parasitology. Drugs and drug resistance
ISSN: 2211-3207
NlmUniqueID: 101576715
Country: Netherlands
Language: English
Volume: 4
Issue: 3
Pages: 310-315

Researcher Affiliations

Matthews, Jacqueline B
  • Moredun Research Institute, Pentlands Science Park, Edinburgh, Midlothian, EH26 0PZ, UK.

Grant Funding

  • 095831 / Wellcome Trust

References

This article includes 78 references
  1. Andersen UV, Howe DK, Dangoudoubiyam S, Toft N, Reinemeyer CR, Lyons ET, Olsen SN, Monrad J, Nejsum P, Nielsen MK. SvSXP: a Strongylus vulgaris antigen with potential for prepatent diagnosis.. Parasit. Vectors 2013;6:84.
    pmc: PMC3623896pubmed: 23557195
  2. Andersen UV, Howe DK, Olsen SN, Nielsen MK. Recent advances in diagnosing pathogenic equine gastrointestinal helminths: the challenge of prepatent detection.. Vet. Parasitol. 2013;192:1–9.
    pubmed: 23199789
  3. Boersema JH, Eysker M, Maas J, van der Aar WM. Comparison of the reappearance of strongyle eggs on foals, yearlings and adult horses after treatment with ivermectin or pyrantel.. Vet. Q. 1996;18:7–9.
    pubmed: 8833604
  4. Boersema JH, Eysker M, Nas JW. Apparent resistance of Parascaris equorum to macrocylic lactones.. Vet. Rec. 2002;150:279–281.
    pubmed: 11924584
  5. Borgsteede FH, Boersma JH, Gaasenbeek CP, van der Burg WP. The reappearance of eggs in faeces of horses after treatment with ivermectin.. Vet. Q. 1993;15:24–26.
    pubmed: 8498011
  6. Bucknell DG, Gasser RB, Beveridge I. The prevalence and epidemiology of gastrointestinal parasites of horses in Victoria, Australia.. Int. J. Parasitol. 1995;25:711–724.
    pubmed: 7657457
  7. Canever RJ, Braga PR, Boeckh A, Grycajuck M, Bier D, Molento MB. Lack of cyathostomin spp. reduction after anthelmintic treatment in horses in Brazil.. Vet. Parasitol. 2013;194:35–39.
    pubmed: 23318166
  8. Coles GC, Bauer C, Borgsteede FH, Geerts S, Klei TR, Taylor MA, Waller PJ. World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) methods for the detection of anthelmintic resistance in nematodes of veterinary importance.. Vet. Parasitol. 1992;44:35–44.
    pubmed: 1441190
  9. Colglazier ML, Enzie FD, Kates KC. Critical anthelmintic trials in ponies with four benzimidazoles: mebendazole, cambendazole, fenbendazole, and albendazole.. J. Parasitol. 1977;63:724–727.
    pubmed: 886410
  10. Corbett CJ, Love S, Moore A, Burden FA, Matthews JB, Denwood MJ. The effectiveness of faecal removal methods of pasture management to control the cyathostomin burden of donkeys.. Parasit. Vectors 2014;7:48.
    pmc: PMC3904009pubmed: 24460700
  11. Cornwell RL, Jones RM. Activity of pyrantel against Parascaris equorum.. Vet. Rec. 1969;85:196–197.
    pubmed: 4897394
  12. Craig TM, Diamond PL, Fernerd MS, Thompson JA. Evidence of ivermectin resistance by Parascaris equorum on a Texas horse farm.. J. Eq. Vet. Sci. 2007;27:67–71.
  13. Cribb NC, Cote NM, Bouré LP, Peregrine AS. Acute small intestinal obstruction associated with Parascaris equorum infection in young horses: 25 cases (1985–2004). N. Z. Vet. J. 2006;54:338–343.
    pubmed: 17151735
  14. Denwood MJ, Reid SWJ, Love S, Nielsen MK, Matthews L, McKendrick IJ, Innocent GT. Comparison of three alternative techniques for analysis of equine faecal egg count reduction test data.. Prev. Vet. Med. 2010;93:316–323.
    pubmed: 19962203
  15. Denwood MJ, Love S, Innocent GT, Matthews L, McKendrick IJ, Hillary N, Smith A, Reid SW. Quantifying the sources of variability in equine faecal egg counts: implications for improving the utility of the method.. Vet. Parasitol. 2012;188:120–126.
    pubmed: 22469484
  16. Dowdall SMJ, Matthews JB, Murphy D, Love S, Proudman CJ. Antigen-specific IgG(T) responses in natural and experimental cyathostomin infection.. Vet. Parasitol. 2002;106:225–242.
    pubmed: 12062511
  17. Dowdall SMJ, Proudman CJ, Klei TR, Mair TS, Matthews JB. Antigen-specific IgGT responses as a marker for larval cyathostomin infection.. Int. J. Parasitol. 2004;34:101–108.
    pubmed: 14711595
  18. Dudeney A, Campbell C, Gerald C. Macrocyclic lactone resistance in cyathostomins.. Vet. Rec. 2008;163:163–164.
    pubmed: 18677003
  19. Duncan JL, Love S. Preliminary observations on an alternative strategy for the control of horse strongyles.. Equine Vet. J. 1991;23:226–228.
    pubmed: 1909236
  20. Gawor JJ. The prevalence and abundance of internal parasites in working horses autopsied in Poland.. Vet. Parasitol. 1995;58:99–108.
    pubmed: 7676606
  21. Giles CJ, Urquhart KA, Longstaffe JA. Larval cyathostomiasis (immature trichonema-induced enteropathy): a report of 15 clinical cases.. Equine Vet. J. 1985;17:196–201.
    pubmed: 4076127
  22. Herd RP. Epidemiology and control of equine strongylosis at Newmarket.. Equine Vet. J. 1986;18:447–452.
    pubmed: 3803357
  23. Hearn FP, Peregrine AS. Identification of foals infected with Parascaris equorum apparently resistant to ivermectin.. J. Am. Vet. Med. Assoc. 2003;223:482–485.
    pubmed: 12930086
  24. Hertzberg H, Schwarzwald CC, Grimm F, Frey CF, Gottstein B, Gerber V. Helminth control in the adult horse: the need for a re-orientation.. Schweiz. Arch. Tierheilkd. 2014;156:61–70.
    pubmed: 24463320
  25. Jacobs DE, Hutchinson MJ, Parker L, Gibbons LM. Equine cyathostomin infection: suppression of faecal egg output with moxidectin.. Vet. Rec. 1995;137:545.
    pubmed: 8592818
  26. Jackson F, Coop RL. The development of anthelmintic resistance in sheep nematodes.. Parasitology 2000;20(Suppl.):S95–107.
    pubmed: 10874713
  27. Kaplan RM. Drug resistance in nematodes of veterinary importance: a status report.. Trends Parasitol. 2004;20:477–481.
    pubmed: 15363441
  28. Kaplan RM, Klei TR, Lyons ET, Lester G, Courtney CH, French DD, Tolliver SC, Vidyashankar AN, Zhao Y. Prevalence of anthelmintic resistant cyathostomes on horse farms.. J. Am. Vet. Med. Assoc. 2004;225:903–910.
    pubmed: 15485051
  29. Kaplan RM, Nielsen MK. An evidence-based approach to equine parasite control: it ain’t the 60s anymore.. Equine Vet. Educ. 2010;22:306–316.
  30. Kuz’mina TA. Strongylids (Nematoda: Strongylidae) of domestic horses in Ukraine: modern state of Fauna and structure of the parasite community.. Parazitologiia 2012;46:127–138.
    pubmed: 22834350
  31. Larsen ML, Ritz C, Peterson SL, Nielsen MK. Determination of ivermectin efficacy against cyathostomins and Parascaris equorum on horse farms using selective therapy.. Vet. J. 2011;188:44–47.
    pubmed: 20385508
  32. Lester HE, Bartley DJ, Morgan ER, Hodgkinson JE, Matthews JB. The spatial distribution of strongyle eggs in horse faeces.. J. Eq. Vet. Sci. 2012;32:S33–S34.
  33. 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.
    pubmed: 24068698
  34. Lester HE, Spanton J, Stratford CH, Bartley DJ, Morgan ER, Hodgkinson JE, Coumbe K, Mair T, Swan B, Lemon G, Cookson R, Matthews JB. Anthelmintic efficacy against cyathostomins in horses in Southern England.. Vet. Parasitol. 2013;197:189–196.
    pubmed: 23830687
  35. Lester HE, Matthews JB. Faecal worm egg count analysis for targeting anthelmintic treatment in horses: points to consider.. Equine Vet. J. 2014;46:139–145.
    pubmed: 24131301
  36. Lyons E, Tolliver S, Ionita M, Collins S. Evaluation of parasiticidal activity of fenbendazole, ivermectin, oxibendazole, and pyrantel pamoate in horse foals with emphasis on ascarids (Parascaris equorum) in field studies on five farms in Central Kentucky in 2007.. Parasitol. Res. 2008;103:287–291.
    pubmed: 18470536
  37. Lyons ET, Tolliver SC, Collins SS. Probable reason why small strongyle EPG counts are returning “early” after ivermectin treatment of horses on a farm in Central Kentucky.. Parasitol. Res. 2009;104:569–574.
    pubmed: 18931857
  38. Lyons ET, Tolliver SC, Kuzmina TA, Collins SS. Critical tests evaluating efficacy of moxidectin against small strongyles in horses from a herd for which reduced activity had been found in field tests in Central Kentucky.. Parasitol. Res. 2010;107:1495–1498.
    pubmed: 20714749
  39. Lyons E, Tolliver S, Collins S, Ionita M, Kuzmina T, Rossano M. Field tests demonstrating reduced activity of ivermectin and moxidectin against small strongyles in horses on 14 farms in Central Kentucky in 2007–2009.. Parasitol. Res. 2011;108:355–360.
    pubmed: 20862493
  40. Lyons ET, Tolliver SC. Further indication of lowered activity of ivermectin on immature small strongyles in the intestinal lumen of horses on a farm in Central Kentucky.. Parasitol. Res. 2013;12:889–891.
    pubmed: 22948206
  41. MacKay RJ, Urquhart KA. An outbreak of eosinophilic bronchitis in horses possibly associated with Dictyocaulus arnfieldi infection.. Equine Vet. J. 1979;11:110–112.
    pubmed: 157874
  42. Mair TS. Outbreak of larval cyathostomiasis among a group of yearling and two-year-old horses.. Vet. Rec. 1994;135:598–600.
    pubmed: 7900244
  43. Matthews JB. An update on cyathostomins: anthelmintic resistance and worm control.. Eq. Vet. Ed. 2008;20:552–560.
  44. Matthews JB. The future of helminth control in horses.. Equine Vet. J. 2014;46:10–11.
    pubmed: 24329582
  45. McWilliam HEG, Nisbet AJ, Dowdall SMJ, Hodgkinson JE, Matthews JB. Identification and characterisation of a potential immunodiagnostic marker for larval cyathostominosis.. Int. J. Parasitol. 2010;40:265–275.
    pubmed: 19703459
  46. Mercier P, Chick B, Alves-Branco F, White CR. Comparative efficacy, persistent efficacy and treatment intervals of anthelmintic pastes in naturally infected horses.. Vet. Par. 2001;99:29–39.
    pubmed: 11445153
  47. Molento MB, Antunes J, Bentes RN, Coles GC. Anthelmintic resistant nematodes in Brazilian horses.. Vet. Rec. 2008;162:384–385.
    pubmed: 18359933
  48. Monahan CM, Chapman MR, Taylor HW, French DD, Klei TR. Comparison of moxidectin oral gel and ivermectin oral paste against a spectrum of internal parasites of ponies with special attention to encysted cyathostome larvae.. Vet. Parasitol. 1996;63:225–235.
    pubmed: 8966989
  49. Murphy D, Love S. The pathogenic effects of experimental cyathostome infections in ponies.. Vet. Parasitol. 1997;70:99–110.
    pubmed: 9195714
  50. Nielsen MK, Vidyashankar AN, Andersen UV, Delisi K, Pilegaard K, Kaplan RM. Effects of fecal collection and storage factors on strongylid egg counts in horses.. Vet. Parasitol. 2010;167:55–61.
    pubmed: 19850412
  51. Nielsen MK, Vidyashankar AN, Olsen SN, Monrad J, Thamsborg SM. Strongylus vulgaris associated with usage of selective therapy on Danish horse farms: is it reemerging?. Vet. Parasitol. 2012;189:260–266.
    pubmed: 22703964
  52. Ogbourne CP. The prevalence, relative abundance and site distribution of nematodes of the subfamily Cyathostominae in horses killed in Britain.. J. Helminthol. 1976;50:203–214.
    pubmed: 993579
  53. Osterman Lind E, Kuzmina T, Uggla A, Waller P, Hoglund J. A field study on the effect of some anthelmintics on cyathostomins of horses in Sweden.. Vet. Res. Comm. 2007;31:53–65.
    pubmed: 17186406
  54. Owen JM. Liver fluke infection in horses and ponies.. Equine Vet. J. 1977;9:29–31.
    pubmed: 837900
  55. Parry JM, Fisher MA, Grimshaw WT, Jacobs DE. Anthelmintic dosing intervals for horses: comparison of three chemical groups.. Vet. Rec. 1993;133:346–347.
    pubmed: 8236679
  56. Ramsey YH, Christley RM, Matthews JB, Hodgkinson JE, McGoldrick J, Love S. Seasonal development of Cyathostominae larvae on pasture in a northern temperate region of the United Kingdom.. Vet. Parasitol. 2004;119:307–318.
    pubmed: 15154595
  57. Reinemeyer CR. Anthelmintic resistance in non-strongylid parasites of horses.. Vet. Parasitol. 2012;185:9–15.
    pubmed: 22078748
  58. Reinemeyer CR, Nielsen MK. Parasitism and colic.. Vet. Clin. North. Am. Equine Pract. 2009;25:233–245.
    pubmed: 19580936
  59. Relf VE, Morgan ER, Hodgkinson JE, Matthews JB. Helminth excretion with regard to age, gender and management practices on UK Thoroughbred studs.. Parasitology 2013;140:641–652.
    pubmed: 23351718
  60. Relf VE, Lester HE, Morgan ER, Hodgkinson JE, Matthews JB. Anthelmintic efficacy on UK Thoroughbred stud farms.. Int. J. Parasitol. 2014;44:507–514.
    pubmed: 24746779
  61. Robert M, Hu W, Nielsen MK, Stowe CJ. Attitudes towards implementation of surveillance-based parasite control on Kentucky Thoroughbred farms – current strategies, awareness, and willingness-to-pay.. Equine Vet. J. 2014 Sep 5.
    pubmed: 25196091doi: 10.1111/evj.12344google scholar: lookup
  62. Rossano MG, Smith AR, Lyons ET. Shortened strongyle-type egg reappearance periods in naturally infected horse treated with moxidectin and failure of a larvicidal dose of fenbendazole to reduce faecal egg counts.. Vet. Parasitol. 2010;173:349–352.
    pubmed: 20675055
  63. Sangster NC. Managing parasiticide resistance.. Vet. Parasitol. 2001;98:89–109.
    pubmed: 11516581
  64. Schougaard H, Nielsen MK. Apparent ivermectin resistance of Parascaris equorum in foals in Denmark.. Vet. Rec. 2007;160:439–440.
    pubmed: 17400903
  65. Stoneham S, Coles GC. Ivermectin resistance in Parascaris equorum.. Vet. Rec. 2006;158:552.
    pubmed: 16632539
  66. Stratford CH, Lester HE, Morgan ER, Pickles KJ, Relf V, McGorum BC, Matthews JB. A questionnaire study of equine gastrointestinal parasite control in Scotland.. Equine Vet. J. 2014;46:25–31.
    pubmed: 23879737
  67. Stratford CH, Lester HE, Pickles KJ, McGorum BC, Matthews JB. An investigation of anthelmintic efficacy against strongyles on equine yards in Scotland.. Equine Vet. J. 2014;46:17–24.
    pubmed: 23662803
  68. Tarigo-Martinie JL, Wyatt AR, Kaplan RM. Prevalence and clinical implications of anthelmintic resistance in cyathostomes of horses.. J. Am. Vet. Med. Assoc. 2001;218:1957–1960.
    pubmed: 11417741
  69. Torgerson P, Schnyder M, Hertzberg H. Detection of anthelmintic resistance: a comparison of mathematical techniques.. Vet. Parasitol. 2005;128:291–298.
    pubmed: 15740866
  70. Torgerson PR, Paul M, Furrer R. Evaluating faecal egg count reduction using a specifically designed package “eggCounts” in R and a user friendly web interface.. Int. J. Parasitol. 2014;44:299–303.
    pubmed: 24556564
  71. Trawford AF, Burden FA. Drug resistant cyathostomins in donkey herds; lessons in management for all equids.. J. Equine Vet. Sci. 2012;32:43.
  72. Traversa D, von Samson-Himmelstjerna G, Demeler J, Milillo P, Schurmann S, Barnes H, Otranto D, Perrucci S, di Regalbono AF, Beraldo P, Boeckh A, Cobb R. Anthelmintic resistance in cyathostomin populations from horse yards in Italy, United Kingdom and Germany.. Parasit. Vectors 2009;2(Suppl 2):S2.
    pmc: PMC2751838pubmed: 19778463
  73. Traversa D, Castagna G, von Samson-Himmelstjerna G, Meloni S, Bartolini R, Geurden T, Pearce MC, Woringer E, Besognet B, Milillo P, D’Espois M. Efficacy of major anthelmintics against horse cyathostomins in France.. Vet. Parasitol. 2012;188:294–300.
    pubmed: 22538094
  74. van Wyk JA. Refugia- overlooked as perhaps the most potent factor concerning the development of anthelmintic resistance.. Onderstepoort J. Vet. Res. 2001;68:55–67.
    pubmed: 11403431
  75. Vidyashankar AN, Kaplan RM, Chan S. Statistical approach to measure the efficacy of anthelmintic treatment on horse farms.. Parasitology 2007;134:2027–2039.
    pubmed: 17714603
  76. Vidyashankar AN, Hanlon BM, Kaplan RM. Statistical and biological considerations in evaluating drug efficacy in equine strongyle parasites using fecal egg count data.. Vet. Parasitol. 2012;185:45–56.
    pubmed: 22119386
  77. von Samson-Himmelstjerna G, Fritzen B, Demeler J, Schürmann S, Rohn K, Schnieder T, Epe C. Cases of reduced cyathostomin egg-reappearance period and failure of Parascaris equorum egg count reduction following ivermectin treatment as well as survey on pyrantel efficacy on German horse farms.. Vet. Parasitol. 2007;144:74–80.
    pubmed: 17112667
  78. Xiao L, Herd RP, Majewski GA. Comparative efficacy of moxidectin and ivermectin against hypobiotic and encysted cyathostomes and other equine parasites.. Vet. Parasitol. 1994;53:83–90.
    pubmed: 8091622

Citations

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  1. Ullah A, Geng M, Chen W, Zhu Q, Shi L, Zhang X, Akhtar MF, Wang C, Khan MZ. Effect of Parasitic Infections on Hematological Profile, Reproductive and Productive Performance in Equines. Animals (Basel) 2025 Nov 14;15(22).
    doi: 10.3390/ani15223294pubmed: 41302002google scholar: lookup
  2. Šarkūnas M, Schwahn A, Suleimanova K. A pilot study on the potency of injectable vs. oral moxidectin formulation to suppress strongyle egg excretion in horses at twice lower dose. Helminthologia 2025 Jun;62(2):87-94.
    doi: 10.2478/helm-2025-0018pubmed: 41058774google scholar: lookup
  3. Rodriguez Velazquez D, Forte L, Varela Guerrero JA, Díaz Alvarado T, Elghandour MMMY, Maggiolino A, De Palo P, Salem AZM. Could Mesquite (Prosopis juliflora) Help Control Gastrointestinal Parasites in Horses?. Animals (Basel) 2025 Apr 28;15(9).
    doi: 10.3390/ani15091245pubmed: 40362060google scholar: lookup
  4. Kuzmina TA, Königová A, Antipov A, Kuzmin Y, Kharchenko V, Syrota Y. Changes in equine strongylid communities after two decades of annual anthelmintic treatments at the farm level. Parasitol Res 2024 Nov 25;123(11):394.
    doi: 10.1007/s00436-024-08417-5pubmed: 39585485google scholar: lookup
  5. Merridale-Punter MS, Wiethoelter AK, El-Hage CM, Patrick C, Hitchens PL. Common clinical findings identified in working equids in low- and middle-income countries from 2005 to 2021. PLoS One 2024;19(6):e0304755.
    doi: 10.1371/journal.pone.0304755pubmed: 38837970google scholar: lookup
  6. Abbas G, Stevenson MA, Bauquier J, Beasley A, Jacobson C, El-Hage C, Wilkes EJA, Carrigan P, Cudmore L, Hurley J, Beveridge I, Nielsen MK, Hughes KJ, Jabbar A. Assessment of worm control practices recommended by equine veterinarians in Australia. Front Vet Sci 2023;10:1305360.
    doi: 10.3389/fvets.2023.1305360pubmed: 38026649google scholar: lookup
  7. Lejeune M, Mann S, White H, Maguire D, Hazard J, Young R, Stone C, Antczak D, Bowman D. Evaluation of Fecal Egg Count Tests for Effective Control of Equine Intestinal Strongyles. Pathogens 2023 Oct 26;12(11).
    doi: 10.3390/pathogens12111283pubmed: 38003748google scholar: lookup
  8. Matthews JB, Peczak N, Lightbody KL. The Use of Innovative Diagnostics to Inform Sustainable Control of Equine Helminth Infections. Pathogens 2023 Oct 11;12(10).
    doi: 10.3390/pathogens12101233pubmed: 37887749google scholar: lookup
  9. Osterman-Lind E, Holmberg M, Grandi G. Selective Anthelmintic Treatment in Horses in Sweden Based on Coprological Analyses: Ten-Year Results. Animals (Basel) 2023 Aug 28;13(17).
    doi: 10.3390/ani13172741pubmed: 37685005google scholar: lookup
  10. Buono F, Veneziano V, Veronesi F, Molento MB. Horse and donkey parasitology: differences and analogies for a correct diagnostic and management of major helminth infections. Parasitology 2023 Oct;150(12):1119-1138.
    doi: 10.1017/S0031182023000525pubmed: 37221816google scholar: lookup
  11. Elghandour MMMY, Maggiolino A, Vázquez-Mendoza P, Alvarado-Ramírez ER, Cedillo-Monroy J, De Palo P, Salem AZM. Moringa oleifera as a Natural Alternative for the Control of Gastrointestinal Parasites in Equines: A Review. Plants (Basel) 2023 May 8;12(9).
    doi: 10.3390/plants12091921pubmed: 37176979google scholar: lookup
  12. Harrington S, Pyche J, Burns AR, Spalholz T, Ryan KT, Baker RJ, Ching J, Rufener L, Lautens M, Kulke D, Vernudachi A, Zamanian M, Deuther-Conrad W, Brust P, Roy PJ. Nemacol is a small molecule inhibitor of C. elegans vesicular acetylcholine transporter with anthelmintic potential. Nat Commun 2023 Mar 31;14(1):1816.
    doi: 10.1038/s41467-023-37452-6pubmed: 37002199google scholar: lookup
  13. Estrem B, Wang J. Programmed DNA elimination in the parasitic nematode Ascaris. PLoS Pathog 2023 Feb;19(2):e1011087.
    doi: 10.1371/journal.ppat.1011087pubmed: 36730159google scholar: lookup
  14. Boelow H, Krücken J, von Samson-Himmelstjerna G. Epidemiological study on factors influencing the occurrence of helminth eggs in horses in Germany based on sent-in diagnostic samples. Parasitol Res 2023 Mar;122(3):749-767.
    doi: 10.1007/s00436-022-07765-4pubmed: 36627515google scholar: lookup
  15. Macdonald SL, Abbas G, Ghafar A, Gauci CG, Bauquier J, El-Hage C, Tennent-Brown B, Wilkes EJA, Beasley A, Jacobson C, Cudmore L, Carrigan P, Hurley J, Beveridge I, Hughes KJ, Nielsen MK, Jabbar A. Egg reappearance periods of anthelmintics against equine cyathostomins: The state of play revisited. Int J Parasitol Drugs Drug Resist 2023 Apr;21:28-39.
    doi: 10.1016/j.ijpddr.2022.12.002pubmed: 36543048google scholar: lookup
  16. Nielsen MK. Anthelmintic resistance in equine nematodes: Current status and emerging trends. Int J Parasitol Drugs Drug Resist 2022 Dec;20:76-88.
    doi: 10.1016/j.ijpddr.2022.10.005pubmed: 36342004google scholar: lookup
  17. McTigue FE, Mansbridge SC, Pyatt AZ. Equine Anthelmintic Resistance: Horse Owner and Yard Manager Perception of the Barriers Affecting Strategic Control Measures in England. Vet Sci 2022 Oct 11;9(10).
    doi: 10.3390/vetsci9100560pubmed: 36288173google scholar: lookup
  18. Dauparaitė E, Kupčinskas T, Varady M, Petkevičius S. Anthelmintic resistance of horse strongyle nematodes to fenbendazole in Lithuania. Acta Vet Scand 2022 Sep 15;64(1):26.
    doi: 10.1186/s13028-022-00645-ypubmed: 36109767google scholar: lookup
  19. Cain JL, Nielsen MK. The equine ascarids: resuscitating historic model organisms for modern purposes. Parasitol Res 2022 Oct;121(10):2775-2791.
    doi: 10.1007/s00436-022-07627-zpubmed: 35986167google scholar: lookup
  20. Malsa J, Courtot É, Boisseau M, Dumont B, Gombault P, Kuzmina TA, Basiaga M, Lluch J, Annonay G, Dhorne-Pollet S, Mach N, Sutra JF, Wimel L, Dubois C, Guégnard F, Serreau D, Lespine A, Sallé G, Fleurance G. Effect of sainfoin (Onobrychis viciifolia) on cyathostomin eggs excretion, larval development, larval community structure and efficacy of ivermectin treatment in horses. Parasitology 2022 Sep;149(11):1439-1449.
    doi: 10.1017/S0031182022000853pubmed: 35929352google scholar: lookup
  21. Jürgenschellert L, Krücken J, Bousquet E, Bartz J, Heyer N, Nielsen MK, von Samson-Himmelstjerna G. Occurrence of Strongylid Nematode Parasites on Horse Farms in Berlin and Brandenburg, Germany, With High Seroprevalence of Strongylus vulgaris Infection. Front Vet Sci 2022;9:892920.
    doi: 10.3389/fvets.2022.892920pubmed: 35754549google scholar: lookup
  22. Özben M, von Samson-Himmelstjerna G, Freiin von Streit MKB, Wilkes EJA, Hughes KJ, Krücken J. Absence of Polymorphisms in Codons 167, 198 and 200 of All Seven β-Tubulin Isotypes of Benzimidazole Susceptible and Resistant Parascaris spp. Specimens from Australia. Pathogens 2022 Apr 20;11(5).
    doi: 10.3390/pathogens11050490pubmed: 35631011google scholar: lookup
  23. Boelow H, Krücken J, Thomas E, Mirams G, von Samson-Himmelstjerna G. Comparison of FECPAK(G2), a modified Mini-FLOTAC technique and combined sedimentation and flotation for the coproscopic examination of helminth eggs in horses. Parasit Vectors 2022 May 12;15(1):166.
    doi: 10.1186/s13071-022-05266-ypubmed: 35549990google scholar: lookup
  24. Walker M, Freitas LT, Halder JB, Brack M, Keiser J, King CH, Levecke B, Ai-Lian Lim Y, Pieri O, Sow D, Stothard JR, Webster JP, Zhou XN, Terry RF, Guérin PJ, Basáñez MG. Improving anthelmintic treatment for schistosomiasis and soil-transmitted helminthiases through sharing and reuse of individual participant data. Wellcome Open Res 2022;7:5.
    doi: 10.12688/wellcomeopenres.17468.1pubmed: 35493199google scholar: lookup
  25. Morgan ER, Lanusse C, Rinaldi L, Charlier J, Vercruysse J. Confounding factors affecting faecal egg count reduction as a measure of anthelmintic efficacy. Parasite 2022;29:20.
    doi: 10.1051/parasite/2022017pubmed: 35389336google scholar: lookup
  26. Nápravníková J, Várady M, Vadlejch J. Total Failure of Fenbendazole to Control Strongylid Infections in Czech Horse Operations. Front Vet Sci 2022;9:833204.
    doi: 10.3389/fvets.2022.833204pubmed: 35265696google scholar: lookup
  27. Rollins RL, Qader M, Gosnell WL, Wang C, Cao S, Cowie RH. A validated high-throughput method for assaying rat lungworm (Angiostrongylus cantonensis) motility when challenged with potentially anthelmintic natural products from Hawaiian fungi. Parasitology 2022 Mar 3;149(6):1-28.
    doi: 10.1017/S0031182022000191pubmed: 35236524google scholar: lookup
  28. Dauparaitė E, Kupčinskas T, Hoglund J, Petkevičius S. A Survey of Control Strategies for Equine Small Strongyles in Lithuania. Helminthologia 2021 Sep;58(3):225-232.
    doi: 10.2478/helm-2021-0031pubmed: 34934386google scholar: lookup
  29. Abbas G, Ghafar A, Hurley J, Bauquier J, Beasley A, Wilkes EJA, Jacobson C, El-Hage C, Cudmore L, Carrigan P, Tennent-Brown B, Gauci CG, Nielsen MK, Hughes KJ, Beveridge I, Jabbar A. Cyathostomin resistance to moxidectin and combinations of anthelmintics in Australian horses. Parasit Vectors 2021 Dec 4;14(1):597.
    doi: 10.1186/s13071-021-05103-8pubmed: 34863271google scholar: lookup
  30. Podlipná R, Navrátilová M, Raisová Stuchlíková L, Moťková K, Langhansová L, Skálová L, Szotáková B. Soybean (Glycine max) Is Able to Absorb, Metabolize and Accumulate Fenbendazole in All Organs Including Beans. Int J Mol Sci 2021 Jun 22;22(13).
    doi: 10.3390/ijms22136647pubmed: 34206260google scholar: lookup
  31. Trailovic SM, Rajkovic M, Marjanovic DS, Neveu C, Charvet CL. Action of Carvacrol on Parascaris sp. and Antagonistic Effect on Nicotinic Acetylcholine Receptors. Pharmaceuticals (Basel) 2021 May 26;14(6).
    doi: 10.3390/ph14060505pubmed: 34073197google scholar: lookup
  32. Louro M, Kuzmina TA, Bredtmann CM, Diekmann I, de Carvalho LMM, von Samson-Himmelstjerna G, Krücken J. Genetic variability, cryptic species and phylogenetic relationship of six cyathostomin species based on mitochondrial and nuclear sequences. Sci Rep 2021 Apr 15;11(1):8245.
    doi: 10.1038/s41598-021-87500-8pubmed: 33859247google scholar: lookup
  33. Zanet S, Battisti E, Labate F, Oberto F, Ferroglio E. Reduced Efficacy of Fenbendazole and Pyrantel Pamoate Treatments against Intestinal Nematodes of Stud and Performance Horses. Vet Sci 2021 Mar 5;8(3).
    doi: 10.3390/vetsci8030042pubmed: 33807857google scholar: lookup
  34. Wang J. Genomics of the Parasitic Nematode Ascaris and Its Relatives. Genes (Basel) 2021 Mar 28;12(4).
    doi: 10.3390/genes12040493pubmed: 33800545google scholar: lookup
  35. Ramalho Sousa S, Anastácio S, Nóvoa M, Paz-Silva A, Madeira de Carvalho LM. Gastrointestinal Parasitism in Miranda Donkeys: Epidemiology and Selective Control of Strongyles Infection in the Northeast of Portugal. Animals (Basel) 2021 Jan 11;11(1).
    doi: 10.3390/ani11010155pubmed: 33440886google scholar: lookup
  36. Kotze AC, Gilleard JS, Doyle SR, Prichard RK. Challenges and opportunities for the adoption of molecular diagnostics for anthelmintic resistance. Int J Parasitol Drugs Drug Resist 2020 Dec;14:264-273.
    doi: 10.1016/j.ijpddr.2020.11.005pubmed: 33307336google scholar: lookup
  37. Fesseha H, Mathewos M, Kidanemariam F. Anthelmintic Efficacy of Strongyle Nematodes to Ivermectin and Fenbendazole on Working Donkeys (Equus asinus) in and around Hosaena Town, Southern Ethiopia. Vet Med Int 2020;2020:4868797.
    doi: 10.1155/2020/4868797pubmed: 33029340google scholar: lookup
  38. Willis C, Nyffeler J, Harrill J. Phenotypic Profiling of Reference Chemicals across Biologically Diverse Cell Types Using the Cell Painting Assay. SLAS Discov 2020 Aug;25(7):755-769.
    doi: 10.1177/2472555220928004pubmed: 32546035google scholar: lookup
  39. Jenkins E, Backwell AL, Bellaw J, Colpitts J, Liboiron A, McRuer D, Medill S, Parker S, Shury T, Smith M, Tschritter C, Wagner B, Poissant J, McLoughlin P. Not playing by the rules: Unusual patterns in the epidemiology of parasites in a natural population of feral horses (Equus caballus) on Sable Island, Canada. Int J Parasitol Parasites Wildl 2020 Apr;11:183-190.
    doi: 10.1016/j.ijppaw.2020.02.002pubmed: 32095427google scholar: lookup
  40. Tydén E, Jansson A, Ringmark S. Parasites in Horses Kept in A 2.5 Year-Round Grazing System in Nordic Conditions without Supplementary Feeding. Animals (Basel) 2019 Dec 17;9(12).
    doi: 10.3390/ani9121156pubmed: 31861066google scholar: lookup
  41. Prichard RK, Geary TG. Perspectives on the utility of moxidectin for the control of parasitic nematodes in the face of developing anthelmintic resistance. Int J Parasitol Drugs Drug Resist 2019 Aug;10:69-83.
    doi: 10.1016/j.ijpddr.2019.06.002pubmed: 31229910google scholar: lookup
  42. Dubois O, Allanic C, Charvet CL, Guégnard F, Février H, Théry-Koné I, Cortet J, Koch C, Bouvier F, Fassier T, Marcon D, Magnin-Robert JB, Peineau N, Courtot E, Huau C, Meynadier A, Enguehard-Gueiffier C, Neveu C, Boudesocque-Delaye L, Sallé G. Lupin (Lupinus spp.) seeds exert anthelmintic activity associated with their alkaloid content. Sci Rep 2019 Jun 21;9(1):9070.
    doi: 10.1038/s41598-019-45654-6pubmed: 31227784google scholar: lookup
  43. Pillai MR, Mihi B, Ishiwata K, Nakamura K, Sakuragi N, Finkelstein DB, McGargill MA, Nakayama T, Ayabe T, Coleman ML, Bix M. Myc-induced nuclear antigen constrains a latent intestinal epithelial cell-intrinsic anthelmintic pathway. PLoS One 2019;14(2):e0211244.
    doi: 10.1371/journal.pone.0211244pubmed: 30807587google scholar: lookup
  44. Charvet CL, Guégnard F, Courtot E, Cortet J, Neveu C. Nicotine-sensitive acetylcholine receptors are relevant pharmacological targets for the control of multidrug resistant parasitic nematodes. Int J Parasitol Drugs Drug Resist 2018 Dec;8(3):540-549.
    doi: 10.1016/j.ijpddr.2018.11.003pubmed: 30502120google scholar: lookup
  45. Palomero AM, Hernández JA, Cazapal-Monteiro CF, Balán FA, Silva MI, Paz-Silva A, Sánchez-Andrade R, Vázquez MSA. Implementation of Biological Control to the Integrated Control of Strongyle Infection among Wild Captive Equids in a Zoological Park. Biomed Res Int 2018;2018:4267683.
    doi: 10.1155/2018/4267683pubmed: 29984232google scholar: lookup
  46. Blanchard A, Guégnard F, Charvet CL, Crisford A, Courtot E, Sauvé C, Harmache A, Duguet T, O'Connor V, Castagnone-Sereno P, Reaves B, Wolstenholme AJ, Beech RN, Holden-Dye L, Neveu C. Deciphering the molecular determinants of cholinergic anthelmintic sensitivity in nematodes: When novel functional validation approaches highlight major differences between the model Caenorhabditis elegans and parasitic species. PLoS Pathog 2018 May;14(5):e1006996.
    doi: 10.1371/journal.ppat.1006996pubmed: 29719008google scholar: lookup
  47. Clark A, Sallé G, Ballan V, Reigner F, Meynadier A, Cortet J, Koch C, Riou M, Blanchard A, Mach N. Strongyle Infection and Gut Microbiota: Profiling of Resistant and Susceptible Horses Over a Grazing Season. Front Physiol 2018;9:272.
    doi: 10.3389/fphys.2018.00272pubmed: 29618989google scholar: lookup
  48. Partridge FA, Brown AE, Buckingham SD, Willis NJ, Wynne GM, Forman R, Else KJ, Morrison AA, Matthews JB, Russell AJ, Lomas DA, Sattelle DB. An automated high-throughput system for phenotypic screening of chemical libraries on C. elegans and parasitic nematodes. Int J Parasitol Drugs Drug Resist 2018 Apr;8(1):8-21.
    doi: 10.1016/j.ijpddr.2017.11.004pubmed: 29223747google scholar: lookup
  49. Sallé G, Cortet J, Bois I, Dubès C, Guyot-Sionest Q, Larrieu C, Landrin V, Majorel G, Wittreck S, Woringer E, Couroucé A, Guillot J, Jacquiet P, Guégnard F, Blanchard A, Leblond A. Risk factor analysis of equine strongyle resistance to anthelmintics. Int J Parasitol Drugs Drug Resist 2017 Dec;7(3):407-415.
    doi: 10.1016/j.ijpddr.2017.10.007pubmed: 29149701google scholar: lookup
  50. Peachey LE, Pinchbeck GL, Matthews JB, Burden FA, Lespine A, von Samson-Himmelstjerna G, Krücken J, Hodgkinson JE. P-glycoproteins play a role in ivermectin resistance in cyathostomins. Int J Parasitol Drugs Drug Resist 2017 Dec;7(3):388-398.
    doi: 10.1016/j.ijpddr.2017.10.006pubmed: 29121562google scholar: lookup
  51. Bredtmann CM, Krücken J, Murugaiyan J, Kuzmina T, von Samson-Himmelstjerna G. Nematode Species Identification-Current Status, Challenges and Future Perspectives for Cyathostomins. Front Cell Infect Microbiol 2017;7:283.
    doi: 10.3389/fcimb.2017.00283pubmed: 28702376google scholar: lookup
  52. Seyoum Z, Zewdu A, Dagnachew S, Bogale B. Anthelmintic Resistance of Strongyle Nematodes to Ivermectin and Fenbendazole on Cart Horses in Gondar, Northwest Ethiopia. Biomed Res Int 2017;2017:5163968.
    doi: 10.1155/2017/5163968pubmed: 28265572google scholar: lookup
  53. Love JW, Kelly LA, Lester HE, Nanjiani I, Taylor MA, Robertson C. Investigating anthelmintic efficacy against gastrointestinal nematodes in cattle by considering appropriate probability distributions for faecal egg count data. Int J Parasitol Drugs Drug Resist 2017 Apr;7(1):71-82.
    doi: 10.1016/j.ijpddr.2017.01.002pubmed: 28161555google scholar: lookup
  54. Humphries D, Nguyen S, Kumar S, Quagraine JE, Otchere J, Harrison LM, Wilson M, Cappello M. Effectiveness of Albendazole for Hookworm Varies Widely by Community and Correlates with Nutritional Factors: A Cross-Sectional Study of School-Age Children in Ghana. Am J Trop Med Hyg 2017 Feb 8;96(2):347-354.
    doi: 10.4269/ajtmh.16-0682pubmed: 27895280google scholar: lookup
  55. Wangchuk P, Pearson MS, Giacomin PR, Becker L, Sotillo J, Pickering D, Smout MJ, Loukas A. Compounds Derived from the Bhutanese Daisy, Ajania nubigena, Demonstrate Dual Anthelmintic Activity against Schistosoma mansoni and Trichuris muris. PLoS Negl Trop Dis 2016 Aug;10(8):e0004908.
    doi: 10.1371/journal.pntd.0004908pubmed: 27490394google scholar: lookup
  56. Courtot E, Charvet CL, Beech RN, Harmache A, Wolstenholme AJ, Holden-Dye L, O'Connor V, Peineau N, Woods DJ, Neveu C. Functional Characterization of a Novel Class of Morantel-Sensitive Acetylcholine Receptors in Nematodes. PLoS Pathog 2015 Dec;11(12):e1005267.
    doi: 10.1371/journal.ppat.1005267pubmed: 26625142google scholar: lookup
  57. Wolstenholme AJ, Martin RJ. Anthelmintics - from discovery to resistance. Int J Parasitol Drugs Drug Resist 2014 Dec;4(3):218-9.
    doi: 10.1016/j.ijpddr.2014.10.001pubmed: 25516831google scholar: lookup
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