The activity of closantel as an equine antiparasitic agent.

The research article is focused on testing the effectiveness of the antiparasitic agent, closantel, in combating various parasites in pony foals.

Overview of the Research Methodology

• Eighteen pony foals were intentionally infected with 500 third stage larvae of a specific parasite, Strongylus vulgaris. This was done at different milestones in their life: 2 weeks after birth, as well as at 2, 4, 6 and 8 months of age.
• Throughout the entire study, the pony foals were kept in the same pasture as their mothers. This was done to expose them to a contaminated environment and allow them to naturally contract other parasites.
• From the eighteen pony foals, twelve were chosen and divided into groups of three. They were then given oral treatments of closantel, a known antiparasitic agent. These treatments were administered five times in two-month intervals starting when the pony foals were one month old. The doses varied from 5, 10, 20, to 40 mg kg-1.
• When the pony foals were ten months old, they were necropsied. This allowed the researchers to ascertain the parasitic burdens in their gastrointestinal tracts and the cranial mesenteric arteries.

Findings from the Research

• The results of the study highlight the effectiveness of the antiparasitic closantel in combating various parasites. These include the larval stages of Gasterophilus intestinalis and S. vulgaris, as well as adult S. vulgaris, S. edentatus, Anoplocephala perfoliata and Triodontophorus species.
• However, the high level of effectiveness was only observed when closantel was used at doses of either 20 or 40 mg kg-1.
• These results therefore indicate that the dosage of closantel administred plays a crucial part in its effectiveness as an antiparasitic agent in pony foals.