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Home / Equine Research Bank / Equine Vet J / Equine helminth infections: control by selective chemotherap...
Equine veterinary journal1991; 23(3); 198-200; doi: 10.1111/j.2042-3306.1991.tb02754.x

Equine helminth infections: control by selective chemotherapy.

Abstract: A programme of selective anthelmintic therapy was used in a herd of 31 horses. Faecal egg counts were done during the months of September, November, January, March, May and the following September. Horses with greater than or equal to 100 eggs per gram (epg) were treated with ivermectin, and those with less than 100 epg were not treated. The criteria for adequate internal parasite control in the herd was a median herd faecal egg count of less than or equal to 100 epg. Effectiveness of selective therapy was assessed by faecal egg count after nine months of treatment and was determined to be adequate when a median herd egg count of 0 epg was obtained. However, on returning from pasture the following September, median herd egg count had risen to 325 epg. A statistically significant correlation was seen in the paired September faecal egg counts of the horses in that initial September faecal egg count was predictive for the following September. Initial September faecal egg count was related to the number of anthelmintic treatments required during the period of selective therapy, whereas age of horse was not. We propose that faecal egg counts be incorporated into strategic anthelmintic programmes as an economical tool for identifying and targeting herd members predisposed to shedding elevated numbers of helminth eggs.
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Publication Date: 1991-05-01 PubMed ID: 1884701DOI: 10.1111/j.2042-3306.1991.tb02754.xGoogle Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't

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.

The research investigated the efficacy of a selective drug treatment against parasitic worm infections in a herd of horses. It found that a drug treatment targeting specifically those horses with higher levels of infection was effective in controlling the overall level of parasites in the herd, although levels rose again once horses returned from pasture.

Research Context

  • The focus of this study was a herd of 31 horses which were subjected to a selective anthelmintic therapy. Anthelmintic therapy is a treatment designed to remove parasitic worms (helminths) from the body of the host animal.
  • The ‘selective’ aspect of the treatment refers to the researchers only administering the worming drug ivermectin to the horses with a faecal egg count (FEC) of greater than or equal to 100 eggs per gram (epg). Horses with lower FEC were not treated.

Methodology and Findings

  • FEC was used as a primary method of assessing the level of helminth infection in the horses. It was performed at various times over the duration of the study – September, November, January, March, May and the following September.
  • The effectiveness of the selective drug treatment was deemed adequate when the median FEC in the herd was 0 epg after 9 months of treatment. Although, the count had increased to 325 epg after the horses returned from pasture in the following September.
  • A significant correlation was detected between the FEC of horses in initial and following September, suggesting that the higher initial FEC, the higher it’s likely to be in the subsequent year despite the treatment.
  • The study also found that the initial FEC could predict the number of anti-worm treatments necessary during the selective therapy period. But the age of the horses appeared to have no significant bearing on treatment requirements.

Implications

  • The study concludes that, FEC is a useful tool for strategic worm management programs. It can be economically advantageous to identify and target herd members with elevated helminth egg counts in their faeces.
  • Selective drug treatments can be effective in controlling parasitic infections in a herd, but care must be exercised on pastures where horses may get re-infected.

Cite This Article

APA
Gomez HH, Georgi JR. (1991). Equine helminth infections: control by selective chemotherapy. Equine Vet J, 23(3), 198-200. https://doi.org/10.1111/j.2042-3306.1991.tb02754.x

Publication

Equine veterinary journal
ISSN: 0425-1644
NlmUniqueID: 0173320
Country: United States
Language: English
Volume: 23
Issue: 3
Pages: 198-200

Researcher Affiliations

Gomez, H H
  • Department of Clinical Sciences, New York State College of Veterinary Medicine, Cornell University, Ithaca 14853.
Georgi, J R

    MeSH Terms

    • Animals
    • Costs and Cost Analysis
    • Feces / parasitology
    • Female
    • Helminthiasis / drug therapy
    • Helminthiasis / economics
    • Helminthiasis, Animal
    • Horse Diseases / drug therapy
    • Horses
    • Intestinal Diseases, Parasitic / drug therapy
    • Intestinal Diseases, Parasitic / economics
    • Intestinal Diseases, Parasitic / veterinary
    • Ivermectin / therapeutic use
    • Male
    • Parasite Egg Count / veterinary
    • Seasons

    Citations

    This article has been cited 20 times.
    1. Osterman-Lind E, Hedberg Alm Y, Hassler H, Wilderoth H, Thorolfson H, Tydén E. Evaluation of Strategies to Reduce Equine Strongyle Infective Larvae on Pasture and Study of Larval Migration and Overwintering in a Nordic Climate. Animals (Basel) 2022 Nov 10;12(22).
      doi: 10.3390/ani12223093pubmed: 36428321google scholar: lookup
    2. Dauparaitė E, Kupčinskas T, von Samson-Himmelstjerna G, Petkevičius S. Anthelmintic resistance of horse strongyle nematodes to ivermectin and pyrantel in Lithuania. Acta Vet Scand 2021 Jan 25;63(1):5.
      doi: 10.1186/s13028-021-00569-zpubmed: 33494770google scholar: lookup
    3. Roelfstra L, Quartier M, Pfister K. Preliminary Data from Six Years of Selective Anthelmintic Treatment on Five Horse Farms in France and Switzerland. Animals (Basel) 2020 Dec 15;10(12).
      doi: 10.3390/ani10122395pubmed: 33333748google scholar: lookup
    4. Scala A, Tamponi C, Sanna G, Predieri G, Dessì G, Sedda G, Buono F, Cappai MG, Veneziano V, Varcasia A. Gastrointestinal Strongyles Egg Excretion in Relation to Age, Gender, and Management of Horses in Italy. Animals (Basel) 2020 Dec 3;10(12).
      doi: 10.3390/ani10122283pubmed: 33287298google scholar: lookup
    5. Sauermann CW, Leathwick DM, Lieffering M, Nielsen MK. Climate change is likely to increase the development rate of anthelmintic resistance in equine cyathostomins in New Zealand. Int J Parasitol Drugs Drug Resist 2020 Dec;14:73-79.
      doi: 10.1016/j.ijpddr.2020.09.001pubmed: 32992276google scholar: lookup
    6. Leathwick DM, Sauermann CW, Nielsen MK. Managing anthelmintic resistance in cyathostomin parasites: Investigating the benefits of refugia-based strategies. Int J Parasitol Drugs Drug Resist 2019 Aug;10:118-124.
      doi: 10.1016/j.ijpddr.2019.08.008pubmed: 31491731google scholar: lookup
    7. Saeed MA, Beveridge I, Abbas G, Beasley A, Bauquier J, Wilkes E, Jacobson C, Hughes KJ, El-Hage C, O'Handley R, Hurley J, Cudmore L, Carrigan P, Walter L, Tennent-Brown B, Nielsen MK, Jabbar A. Systematic review of gastrointestinal nematodes of horses from Australia. Parasit Vectors 2019 Apr 29;12(1):188.
      doi: 10.1186/s13071-019-3445-4pubmed: 31036059google scholar: lookup
    8. Harvey AM, Meggiolaro MN, Hall E, Watts ET, Ramp D, Šlapeta J. Wild horse populations in south-east Australia have a high prevalence of Strongylus vulgaris and may act as a reservoir of infection for domestic horses. Int J Parasitol Parasites Wildl 2019 Apr;8:156-163.
      doi: 10.1016/j.ijppaw.2019.01.008pubmed: 30815358google scholar: lookup
    9. Kaspar A, Pfister K, Nielsen MK, Silaghi C, Fink H, Scheuerle MC. Detection of Strongylus vulgaris in equine faecal samples by real-time PCR and larval culture - method comparison and occurrence assessment. BMC Vet Res 2017 Jan 11;13(1):19.
      doi: 10.1186/s12917-016-0918-ypubmed: 28077153google scholar: lookup
    10. Schneider S, Pfister K, Becher AM, Scheuerle MC. Strongyle infections and parasitic control strategies in German horses - a risk assessment. BMC Vet Res 2014 Nov 12;10:262.
      doi: 10.1186/s12917-014-0262-zpubmed: 25387542google scholar: lookup
    11. Kuzmina TA, Lyons ET, Tolliver SC, Dzeverin II, Kharchenko VA. Fecundity of various species of strongylids (Nematoda: Strongylidae)--parasites of domestic horses. Parasitol Res 2012 Dec;111(6):2265-71.
      doi: 10.1007/s00436-012-3077-5pubmed: 22903448google scholar: lookup
    12. Hinney B, Wirtherle NC, Kyule M, Miethe N, Zessin KH, Clausen PH. A questionnaire survey on helminth control on horse farms in Brandenburg, Germany and the assessment of risks caused by different kinds of management. Parasitol Res 2011 Dec;109(6):1625-35.
      doi: 10.1007/s00436-011-2434-0pubmed: 21559764google scholar: lookup
    13. Becher AM, Pfister K. [The efficacy of anthelmintic drugs against horse strongyles in the area of Salzburg and preliminary results of selective anthelmintic treatment]. Wien Klin Wochenschr 2010 Oct;122 Suppl 3:71-5.
      doi: 10.1007/s00508-010-1441-ypubmed: 20924696google scholar: lookup
    14. Nielsen MK. Restrictions of anthelmintic usage: perspectives and potential consequences. Parasit Vectors 2009 Sep 25;2 Suppl 2(Suppl 2):S7.
      doi: 10.1186/1756-3305-2-S2-S7pubmed: 19778468google scholar: lookup
    15. Elsener J, Villeneuve A. Comparative long-term efficacy of ivermectin and moxidectin over winter in Canadian horses treated at removal from pastures for winter housing. Can Vet J 2009 May;50(5):486-90.
      pubmed: 19436633
    16. Getachew M, Feseha G, Trawford A, Reid SW. A survey of seasonal patterns in strongyle faecal worm egg counts of working equids of the central midlands and lowlands, Ethiopia. Trop Anim Health Prod 2008 Dec;40(8):637-42.
      doi: 10.1007/s11250-008-9142-5pubmed: 18975128google scholar: lookup
    17. Slocombe JO, Coté JF, de Gannes RV. The persistence of benzimidazole-resistant cyathostomes on horse farms in Ontario over 10 years and the effectiveness of ivermectin and moxidectin against these resistant strains. Can Vet J 2008 Jan;49(1):56-60.
      pubmed: 18320979
    18. Whitlock F, van Dijk J, Hodgkinson JE, Grewar JD, Newton JR. Reasons to be fearful? Rising proportions of positive faecal worm egg counts among UK horses (2007-2023). Equine Vet J 2025 Nov;57(6):1572-1583.
      doi: 10.1111/evj.14478pubmed: 39840839google scholar: lookup
    19. Hedberg Alm Y, Tydén E, Martin F, Lernå J, Halvarsson P. Farm size and biosecurity measures associated with Strongylus vulgaris infection in horses. Equine Vet J 2025 May;57(3):703-711.
      doi: 10.1111/evj.14212pubmed: 39171858google scholar: lookup
    20. 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
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