Application of a Reverse Line Blot hybridisation assay for the species-specific identification of cyathostomins (Nematoda, Strongylida) from benzimidazole-treated horses in the Slovak Republic.

This research article investigated the presence of benzimidazole-resistant strongyles, a type of worm, on horse farms in Eastern Slovakia. A variety of tests were used to identify seven different species of these worms, which demonstrated that resistance to a commonly used deworming drug, benzimidazoles, is widespread among local horse populations.

Background

• The research aimed to study the prevalence of benzimidazole-resistant strongyles, also known as cyathostomins, in horses on farms in eastern Slovakia.
• Strongyles are common equine intestinal parasites. Benzimidazoles are commonly used deworming drugs which have become less effective due to resistance building up in worm populations.

Methodology

• The researchers conducted a faecal egg count reduction test and an egg hatch assay on five horse farms. These tests were used to identify the presence and extent of resistance to benzimidazoles in the worm populations.
• Faecal samples were collected from horses before and after they were treated with the deworming drugs. Coprocultures were prepared from these samples for further study.
• A Reverse Line Blot assay, a type of molecular test, was used to examine the cyathostomin larvae collected from the preparations. This test allowed the team to identify the specific species of resistant worms present.

Findings and Conclusion

• Faecal egg count reduction values ranged from 0 to 52.5%, suggesting that the deworming drugs had limited effect in reducing the worm population.
• All farms were found positive for benzimidazole-resistant cyathostomins. Seven different species of resistant worms were identified both before and after treatment.
• The findings clearly indicated that resistance to benzimidazoles among the cyathostomin populations was widespread in the surveyed horse farms in the Slovak Republic.
• The researchers concluded that the molecular assay was effective in determining the species-specific distribution of resistant worms under field conditions.