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Parasitology2012; 140(1); 115-128; doi: 10.1017/S003118201200128X

Variation in fecal egg counts in horses managed for conservation purposes: individual egg shedding consistency, age effects and seasonal variation.

Abstract: Cyathostomins are the most prevalent equine intestinal parasites and resistance has been reported in these nematodes against all 3 licensed anthelmintic classes. Strategies need to be developed that are less dependent upon drugs and more reliant on management-based control. To develop these we need to understand natural transmission patterns better. Here, we analysed longitudinal fecal egg count (FEC) data from 5 pony populations used for conservation purposes. We tested how egg excretion varied amongst populations and individuals, and how this was affected by age and climate. There was evidence for consistency in FECs over time at the individual level; this was generally weak and accounted for <10% of the total variance. Animals <5 years old had higher FECs and there was profound seasonal variation in FECs, with highest levels recorded in spring/summer. Effects of monthly temperature and rainfall explained most, but not all, of the observed seasonal variation and associations between climate measures and FECs were stronger in younger versus adult animals. One population was occasionally treated with anthelmintics and analysis of this population suggested that treatment substantially altered the seasonal dynamics. This paper highlights the variability in strongyle egg excretion amongst individuals and the factors involved in this variation.
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Publication Date: 2012-08-16 PubMed ID: 22894917DOI: 10.1017/S003118201200128XGoogle Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The researchers analyzed fecal egg count data from five equine populations to understand natural transmission patterns of cyathostomins, the most prevalent equine intestinal parasites, and how these patterns are affected by age, climate, and anthelmintic treatment. They found individual fecal egg counts are consistent over time, animals less than five years old had higher counts, and counts were highest in spring/summer, which could be mostly, but not fully, linked to temperature and rainfall variations. Anthelmintic treatment significantly altered seasonal dynamics.

Objective of the Study

  • The study aimed to better understand the natural transmission patterns of the most common horse intestinal parasites, cyathostomins. It sought to investigate variation in fecal egg counts (FEC) among different horse populations, the variation among individuals, and the impact of age and climate on FEC.

Study Methodology

  • The researchers collected longitudinal FEC data from five different horse populations used for conservation aims. By analyzing this data, the study examined the factors influencing egg excretion.

Key Findings

  • Individual FECs were found to be consistent over time, but the strength of this consistency was weak, accounting for less than 10 percent of total variance.
  • The study found that animals under five years old had higher FECs, suggesting a relationship between age and the number of eggs excreted.
  • There was a noticeable seasonal variation in FECs, where the highest levels were noted during spring and summer. This seasonal variation was largely explained by changes in temperature and rainfall, but not entirely.
  • Interestingly, the effect of climate changes on FECs seemed to be stronger in young animals compared to adults.

Effect of Anthelmintic Treatment

  • One of the studied populations was occasionally treated with anthelmintics (medications intended to destroy or expel parasitic worms). Analysis of this specific population suggested that this treatment caused a substantial disruption in the usual seasonal dynamics of FECs.

Importance of the Findings

  • This research brings valuable insight into the individual and population-level variation of cyathostomin egg excretion in horses. An understanding of these dynamics is crucial for developing anthelmintic resistance management strategies that are less reliant on drugs and more on management-based control.

Cite This Article

APA
Wood EL, Matthews JB, Stephenson S, Slote M, Nussey DH. (2012). Variation in fecal egg counts in horses managed for conservation purposes: individual egg shedding consistency, age effects and seasonal variation. Parasitology, 140(1), 115-128. https://doi.org/10.1017/S003118201200128X

Publication

Parasitology
ISSN: 1469-8161
NlmUniqueID: 0401121
Country: England
Language: English
Volume: 140
Issue: 1
Pages: 115-128

Researcher Affiliations

Wood, E L D
  • Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, West Mains Road, Edinburgh, UK.
Matthews, J B
    Stephenson, S
      Slote, M
        Nussey, D H

          MeSH Terms

          • Age Factors
          • Animals
          • Anthelmintics / therapeutic use
          • Climate
          • Conservation of Natural Resources
          • Feces / parasitology
          • Horses
          • Parasite Egg Count / veterinary
          • Seasons
          • Strongyle Infections, Equine / drug therapy
          • Strongyle Infections, Equine / epidemiology
          • Strongyle Infections, Equine / parasitology
          • Strongyle Infections, Equine / pathology
          • Strongyle Infections, Equine / transmission
          • United Kingdom / epidemiology

          Grant Funding

          • BB/H021868/1 / Biotechnology and Biological Sciences Research Council

          Citations

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