A study on the prevalence of cyathostomin and Anoplocephala perfoliata infections in Italian horses: diagnostic testing and analysis of factors affecting infection risk.

Overview

• This study investigated the presence of two common parasites, cyathostomins and Anoplocephala perfoliata, in Italian horses using both fecal egg detection and blood antibody tests.
• The research also examined various factors related to the horses and their environment that may influence the risk of infection.

Introduction and Background

• Cyathostomins (small strongyles) and Anoplocephala perfoliata (tapeworm) are parasites that infect horses worldwide and can cause health issues.
• Common diagnostic methods include coprological analysis, which looks for parasite eggs in feces but doesn’t measure total parasite burden accurately.
• Antibody-based tests (ELISA) can indicate infection levels more effectively by detecting immune responses to parasites rather than just eggs shed in feces.

Objectives

• To measure the prevalence of cyathostomin and A. perfoliata infections in horses across Italy.
• To compare two diagnostic approaches: coprological (fecal egg counts) versus serum-based antibody detection (ELISA tests).
• To analyze risk factors at the individual horse level that might influence the likelihood or intensity of infection.

Methods

• Sample Collection:
  • 173 horses sampled across 35 different farms in Italy.
• Diagnostic Testing:
  • Fecal samples were tested for parasitic eggs using Mini-FLOTAC and centrifugation/flotation techniques.
  • Serum samples were tested for parasite-specific antibodies using two ELISA tests:
    • Small Redworm Blood Test for cyathostomins.
    • Tapeworm Blood Test for Anoplocephala perfoliata.
• Data Analysis:
  • Statistical association tests were conducted between test results and factors such as horse sex, age, access to pasture, treatment history, and farm management practices.

Results

• Fecal Egg Detection:
  • Intestinal strongyle eggs found in 140/173 samples (80.9%).
  • Tapeworm eggs found in only 5/173 samples (2.9%), indicating low detection in feces.
• Serum Antibody Testing:
  • For cyathostomins, 39 horses (22.5%) had antibody levels below a 1,000 total worm burden threshold, and 75 horses (43.0%) below 10,000 worms.
  • For tapeworm, 136/173 horses (78.6%) had antibody levels below the treatment threshold, suggesting most had low or no active infection.
• Risk Factor Associations:
  • Cyathostomin antibody levels correlated with horse sex, pasture access, strongyle egg counts, recent deworming treatments, and tapeworm antibody levels.
  • Tapeworm antibody levels related to:
    • Geographical living area.
    • Age category and sex of the horse.
    • Access to pasture and quarantine procedures.
    • Management practices like dung removal.
    • Strongyle egg counts and recent anti-nematode treatments.
    • Cyathostomin antibody levels (showing interaction between infections).

Conclusions and Implications

• The study confirms that cyathostomin infections are widespread in Italian horses and tapeworm infections, though less evident in feces, are also present.
• Antibody-based tests provide valuable information that complements fecal egg counts, especially in detecting overall parasite burden and subclinical infections.
• Risk of infection is influenced by both intrinsic factors like age and sex and extrinsic factors including farm location, pasture management, quarantine, and treatment history.
• Findings suggest that integrated parasite management protocols should consider these individual and environmental risk factors to improve control of these parasites in horse populations.