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Veterinary parasitology1999; 85(2-3); 189-225; doi: 10.1016/s0304-4017(99)00099-0

Pharmacology of anthelmintic resistance in cyathostomes: will it occur with the avermectin/milbemycins?

Abstract: Anthelmintic-resistance has emerged as a problem in several animal industries. In the horse, cyathostome resistance to all available treatments except for the avermectin/milbemycins means that these drugs provide the cornerstone of control. Ivermectin has been available for several years; the related compound moxidectin is more recent. Although we do not know for sure, aspects of moxidectin such as its persistent action and its efficacy against mucosal stages of cyathostomes, may enhance the rate of development of resistance. On the other hand, selection pressure would be reduced if the persistence of moxidectin allows it to be used less frequently in the field. Reduced anthelmintic usage and surveillance of egg reappearance period are the most useful tools in managing resistance.
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Publication Date: 1999-09-15 PubMed ID: 10485365DOI: 10.1016/s0304-4017(99)00099-0Google Scholar: Lookup
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  • Journal Article

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 study addresses the issue of anthelmintic resistance in cyathostomes in horses and explores if such resistance could develop against the drugs avermectin/milbemycins. The research also discusses the role of moxidectin, its possible effects on resistance development, and methods to manage such resistance.

Anthelmintic Resistance in Cyathostomes

  • In the context of the study, cyathostomes refer to a type of parasitic worm that affects horses. The concern raised is regarding the development of resistance in these worms against all existing treatments, with the exception of the drug class avermectin/milbemycins.
  • The study highlights that avermectin/milbemycins currently remain the primary mode of control against these parasitic infections in horses.

Moxidectin and Ivermectin

  • The research mentions two drugs in particular – ivermectin and moxidectin. Ivermectin has been available for use for several years, whereas moxidectin is relatively new.
  • The study proposes that certain characteristics of moxidectin, namely its extended action and its efficacy against the mucosal stages of cyathostomes, may potentially hasten the rate at which resistance develops.

Management of Resistance

  • However, the research suggests that this potential increased rate of resistance development could be counterbalanced if the persistence of moxidectin allows for its less frequent usage. Reduced usage of anthelmintic drugs could potentially decrease the selection pressure, thus slowing down resistance development.
  • The study advocates for reduced anthelmintic usage and regular surveillance of egg reappearance period (the time taken for parasite eggs to reappear in the feces after treatment) as the most feasible ways to manage anthelmintic resistance in cyathostomes.

Cite This Article

APA
Sangster NC. (1999). Pharmacology of anthelmintic resistance in cyathostomes: will it occur with the avermectin/milbemycins? Vet Parasitol, 85(2-3), 189-225. https://doi.org/10.1016/s0304-4017(99)00099-0

Publication

Veterinary parasitology
ISSN: 0304-4017
NlmUniqueID: 7602745
Country: Netherlands
Language: English
Volume: 85
Issue: 2-3
Pages: 189-225

Researcher Affiliations

Sangster, N C
  • Department of Veterinary Anatomy and Pathology University of Sydney, NSW, Australia. n.sangster@vetp.usyd.eu.au

MeSH Terms

  • Animals
  • Anthelmintics / pharmacokinetics
  • Anthelmintics / pharmacology
  • Anthelmintics / therapeutic use
  • Anti-Bacterial Agents / pharmacokinetics
  • Anti-Bacterial Agents / pharmacology
  • Anti-Bacterial Agents / therapeutic use
  • Drug Resistance
  • Horse Diseases / drug therapy
  • Horse Diseases / parasitology
  • Horses
  • Ivermectin / analogs & derivatives
  • Ivermectin / pharmacokinetics
  • Ivermectin / therapeutic use
  • Macrolides
  • Strongylida Infections / drug therapy
  • Strongylida Infections / veterinary
  • Strongyloidea / drug effects

Citations

This article has been cited 18 times.
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