Analyze Diet
Australian veterinary journal1981; 57(4); 172-181; doi: 10.1111/j.1751-0813.1981.tb00504.x

Resistance to benzimidazole anthelmintics in equine strongyles. 2. Evidence of side-resistance, and susceptibility of benzimidazole-resistant strongyles to non-benzimidazole compounds.

Abstract: The susceptibility of a known thiabendazole-resistant population of small strongyles to anthelmintics of both benzimidazole and non-benzimidazole groups, was determined. In the first study, 42 horses infected with thiabendazole-resistant small strongyles were allocated to 6 groups. Treatment groups received one of the following anthelmintics: mebendazole, febantel, febantel plus trichlorphon, morantel tartrate, or a combination of thiabendazole, piperazine and trichlorphon. Morantel tartrate and the thiabendazole/piperazine/trichlorphon combination produced highly significant (p less than 0.001) reductions in faecal strongyle egg counts 20 days post-treatment. Mebendazole, febantel and febantel plus trichlorphon failed to reduce strongyle egg counts significantly. Larval culture and differentiation indicated that in all cases of anthelmintic failure, small strongyles of the sub-family Cyathostominae were involved. Eighteen horses from groups in which treatment had failed were re-allocated to 3 groups. Treatment with either morantel tartrate or haloxon was highly efficient in reducing faecal strongyle egg counts. In the final study, fifty-four horses, infected with benzimidazole-resistant small strongyles were allocated to 10 groups. On day zero, each treatment group received one of the following anthelmintics: thiabendazole, cambendazole, mebendazole, oxibendazole, piperazine, thiabendazole/piperazine, cambendazole/piperazine, mebendazole/piperazine or oxibendazole/piperazine. Oxibendazole, piperazine and the benzimidazole/piperazine combinations produced highly significant reductions in faecal strongyle egg counts 20 days post-treatment (p less than 0.001). When administered alone, benzimidazole anthelmintics failed to reduce strongyle egg counts significantly, with the exception of oxibendazole. Larval culture and differentiation indicated that in all cases of anthelmintic failure, the species involved were small strongyles of subfamily Cyathostominae. There was no significant increase in benzimidazole resistance level (based on in vitro assay) as a result of drug treatment, over one generation.
Publication Date: 1981-04-01 PubMed ID: 7271606DOI: 10.1111/j.1751-0813.1981.tb00504.xGoogle Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
  • Comparative Study
  • 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.

This study investigates the resistance of small strongyles, a type of parasite found in horses, to various anthelmintics (worming drugs). The researchers found that thiabendazole-resistant strongyles responded well to non-benzimidazole drugs and also to a certain combination of benzimidazole compounds. However, other benzimidazole drugs showed less effectiveness.

Methodology of the Study

  • This research involved multiple studies testing the effectiveness of different anthelmintic drugs on horses infected with thiabendazole-resistant small strongyles. The strongyles are parasites in the family of Cyathostominae.
  • In each study, the horses were divided into groups and treated with different anthelmintics. The drugs used included both benzimidazole and non-benzimidazole types, as well as their combinations.
  • The effectiveness of each treatment was evaluated based on the reduction in faecal strongyle egg counts 20 days post-treatment.

Key Findings

  • The first study found that treatment with morantel tartrate, a non-benzimidazole anthelmintic, and a combination of thiabendazole, piperazine and trichlorphon produced significant reductions in strongyle egg counts.
  • In contrast, treatment with mebendazole, febantel, and febantel plus trichlorphon—all benzimidazole anthelmintics—did not significantly decrease strongyle egg counts.
  • When treatments failed, small strongyles of the sub-family Cyathostominae were always found to be involved.
  • In a subsequent study, treatment with either morantel tartrate or haloxon (another non-benzimidazole anthelmintic) were also proved efficient in reducing faecal strongyle egg counts.
  • In the final study, treatments with oxibendazole, piperazine, and combinations of benzimidazole and piperazine were found to significantly reduce faecal strongyle egg counts.
  • On their own, most benzimidazole anthelmintics failed to significantly reduce these counts. The one exception was with oxibendazole.

Conclusion

  • The study concluded that thiabendazole-resistant small strongyles were susceptible to certain non-benzimidazole anthelmintics and to a combination of certain benzimidazole compounds.
  • The research also confirmed that there was no increase in benzimidazole resistance level as a result of drug treatment over one generation.

This research provides valuable insight into the resistance characteristics of these parasites and the effectiveness of different treatment strategies. It helps suggest more effective treatment options for horses infected with benzimidazole-resistant strongyles.

Cite This Article

APA
Webster JH, Baird JD, Gunawan M, Martin IC, Kelly JD. (1981). Resistance to benzimidazole anthelmintics in equine strongyles. 2. Evidence of side-resistance, and susceptibility of benzimidazole-resistant strongyles to non-benzimidazole compounds. Aust Vet J, 57(4), 172-181. https://doi.org/10.1111/j.1751-0813.1981.tb00504.x

Publication

ISSN: 0005-0423
NlmUniqueID: 0370616
Country: England
Language: English
Volume: 57
Issue: 4
Pages: 172-181

Researcher Affiliations

Webster, J H
    Baird, J D
      Gunawan, M
        Martin, I C
          Kelly, J D

            MeSH Terms

            • Animals
            • Anthelmintics / pharmacology
            • Anthelmintics / therapeutic use
            • Benzimidazoles / pharmacology
            • Drug Resistance
            • Feces / parasitology
            • Horses
            • Parasite Egg Count / veterinary
            • Strongyle Infections, Equine / drug therapy
            • Strongyle Infections, Equine / parasitology
            • Strongyloidea / drug effects
            • Thiabendazole / pharmacology

            Citations

            This article has been cited 2 times.
            1. 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
            2. Slocombe JO, Cote JF, McMillan I. Effectiveness of oxibendazole against benzimidazole-resistant strongyles in horses.. Can Vet J 1989 Aug;30(8):663-5.
              pubmed: 17423395