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Parasitology2016; 143(8); 983-997; doi: 10.1017/S0031182016000408

Negative covariance between parasite load and body condition in a population of feral horses.

Abstract: In wild and domestic animals, gastrointestinal parasites can have significant impacts on host development, condition, health, reproduction and longevity. Improving our understanding of the causes and consequences of individual-level variation in parasite load is therefore of prime interest. Here we investigated the relationship between strongyle fecal egg count (FEC) and body condition in a unique, naturalized population of horses that has never been exposed to anthelmintic drugs (Sable Island, Nova Scotia, Canada). We first quantified variation in FEC and condition for 447 individuals according to intrinsic (sex, age, reproductive status, social status) and extrinsic (group size, location, local density) variables. We then quantified the repeatability of measurements obtained over a field season and tested for covariance between FEC and condition. FECs were high relative to other horse populations (mean eggs per gram ± SD = 1543·28 ± 209·94). FECs generally decreased with age, were higher in lactating vs non-lactating females, and unexpectedly lower in males in some part of the island. FECs and condition were both spatially structured, with patterns depending on age, sex and reproductive status. FECs and condition were both repeatable. Most notably, FECs and condition were negatively correlated, especially in adult females.
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Publication Date: 2016-04-06 PubMed ID: 27046508DOI: 10.1017/S0031182016000408Google 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 research studies the relationship between parasite load and body condition in a feral horse population in Sable Island, Nova Scotia, Canada. High levels of strongyle parasite’s eggs were found alongside poor body conditions, highlighting a negative correlation, particularly noticeable in adult females.

Overview of the Study

  • The research team inspected the link between strongyle fecal egg count (FEC) and body condition in a unique population of horses on Sable Island, Nova Scotia, Canada. This population of horses is unique because it has never been exposed to anthelmintic drugs, medicines used to treat parasitic worm infections.
  • The scientists examined 447 individual horses and their variation in FEC and body condition based on intrinsic (sex, age, reproductive status, social status) and extrinsic (group size, location, local density) variables.

Results

  • The researchers found out that the FECs were high compared to other horse populations, with an average of 1543.28 eggs per gram.
  • FECs usually decreased with age. Also, they were higher in lactating females compared to non-lactating ones, and surprisingly lower in males in some regions of the island.
  • Both FECs and body conditions were influenced by factors such as age, sex, and reproductive status, and exhibited patterns depending on these factors.
  • Measurements of both FECs and body condition were repeatable, suggesting consistent trends/traits in the population.
  • But most importantly, a negative correlation was observed between FECs and body condition, especially in adult females. This suggests that the higher the FEC, the poorer the body condition of the horse.

Implication of the Study

  • The strong negative correlation between parasite load and body condition is a crucial finding for wildlife management and conservation perspective. The heavy parasite load leads to poor body conditions, which can in turn affect the reproduction and longevity of the horse population. Thus, managing the parasite load becomes an essential task in maintaining healthy horse populations.

Cite This Article

APA
Debeffe L, McLoughlin PD, Medill SA, Stewart K, Andres D, Shury T, Wagner B, Jenkins E, Gilleard JS, Poissant J. (2016). Negative covariance between parasite load and body condition in a population of feral horses. Parasitology, 143(8), 983-997. https://doi.org/10.1017/S0031182016000408

Publication

Parasitology
ISSN: 1469-8161
NlmUniqueID: 0401121
Country: England
Language: English
Volume: 143
Issue: 8
Pages: 983-997

Researcher Affiliations

Debeffe, Lucie
  • Department of Biology,University of Saskatchewan,112 Science Place, Saskatoon, SK S7N 5E2,Canada.
McLoughlin, Philip D
  • Department of Biology,University of Saskatchewan,112 Science Place, Saskatoon, SK S7N 5E2,Canada.
Medill, Sarah A
  • Department of Biology,University of Saskatchewan,112 Science Place, Saskatoon, SK S7N 5E2,Canada.
Stewart, Kathrine
  • Department of Biology,University of Saskatchewan,112 Science Place, Saskatoon, SK S7N 5E2,Canada.
Andres, Daniel
  • Department of Biology,University of Saskatchewan,112 Science Place, Saskatoon, SK S7N 5E2,Canada.
Shury, Todd
  • Parks Canada Agency,52 Campus Drive,Saskatoon SK S7N 5B4,Canada.
Wagner, Brent
  • Department of Veterinary Microbiology,University of Saskatchewan,52 Campus drive,Saskatoon,SK S7N 5B4,Canada.
Jenkins, Emily
  • Department of Veterinary Microbiology,University of Saskatchewan,52 Campus drive,Saskatoon,SK S7N 5B4,Canada.
Gilleard, John S
  • Department of Comparative Biology and Experimental Medicine,University of Calgary,3330 Hospital Drive,Calgary,AB T2N 4N1,Canada.
Poissant, Jocelyn
  • Department of Comparative Biology and Experimental Medicine,University of Calgary,3330 Hospital Drive,Calgary,AB T2N 4N1,Canada.

MeSH Terms

  • Age Factors
  • Animals
  • Canada
  • Feces / parasitology
  • Female
  • Horse Diseases / parasitology
  • Horses / parasitology
  • Host-Parasite Interactions
  • Male
  • Parasite Egg Count / veterinary
  • Parasite Load
  • Seasons
  • Sex Factors
  • Strongyle Infections, Equine / parasitology
  • Strongylus / isolation & purification
  • Strongylus / physiology

Citations

This article has been cited 34 times.
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