Transmission of endoparasites in horse foals born on the same pasture on a farm in central Kentucky (1996-1999).

The study investigates the prevalence and transmission patterns of endoparasites in horse foals born on the same pasture in central Kentucky over a period of four years (1996-1999). The research found that horses in this area, which had not been treated with antiparasitic drugs for over 20 years, carried 22 different species of endoparasites.

Study Background

• This research was set up to explore the transmission of endoparasites in horse foals born on the same pasture over a four-year period (1996-1999).
• The study was conducted on a horse farm in central Kentucky where horses were not treated with antiparasitic drugs for over two decades. This setting was chosen to understand the natural transmission and prevalence of parasites in an untreated environment.

Methodology and Findings

• The team identified a total of 22 species of parasites including 12 species of small strongyles in the four-year period.
• The transmission patterns of all 35 species of endoparasites explored over the 11-year study were compared.
• Significant findings from the study include an increase in the number of Thelazia lacrymalis and Anoplocephala perfoliata parasites, and a decrease in Gasterophilus intestinalis, Parascaris equorum, and Strongylus vulgaris parasites.

Impact and Implications

• Despite the presence of these parasites, the study noted no clinical problems associated with parasitism in any of the 92 foals involved in the long-term investigation. This indicates that some endoparasites might not have a significant clinical impact in their hosts.
• The findings from the study contribute to an understanding of how changes in parasite populations occur in untreated herds and can form the basis for more effective parasite control strategies in equine practices.