Prevalence of benzimidazole-resistance in equine cyathostome populations in south east England.

The research focuses on studying the prevalence of resistance to a certain type of deworming medication (benzimidazole) in equine parasites, cyathostomes, found in south east England and suggests pyrantel embonate as a more effective treatment.

Research Overview

• The experiment was conducted on 30 stables that were strategically chosen based on certain criteria in south east England.
• Every stable had three groups of 100 horses each, treated with varying substances – fenbendazole, an anthelmintics from benzimidazole family, pyrantel embonate, a non-benzimidazole anthelmintic, and a group left untreated to act as control.

Achieved Results

• The effectiveness of fenbendazole and pyrantel embonate in removing the parasites was measured by the faecal egg-count reduction method.
• The overall effectiveness percentages were determined to be 56.3% and 95.8% for fenbendazole and pyrantel embonate respectively.
• Going into further details, while pyrantel’s effectiveness exceeded 85% in 26 out of 27 stables, fenbendazole’s effectiveness was above this threshold only in 5 out of 27 stables.

Evaluation of Parasite Populations

• Cyathostomes were the primary target of the study since they constituted more than 90% of the larvae cultured from horse faeces before and after the given treatments.
• Another parasite, Trichostrongylus axei, was detected in 20 locations, and parasites from the Strongylus species were located only in five.

Prevalence and Control of Benzimidazole-Resistance in Cyathostomes

• The data clearly indicates a widespread prevalence of benzimidazole-resistance in cyathostomes, especially at stables which regularly used benzimidazole anthelmintics and housed more than nine horses.
• However, it was found that these benzimidazole-resistant strains of cyathostomes could effectively be controlled with pyrantel embonate, a non-benzimidazole anthelmintic.