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Parasites & vectors2022; 15(1); 50; doi: 10.1186/s13071-022-05168-z

Parasite dynamics in untreated horses through one calendar year.

Abstract: Horses are host to a plethora of parasites. Knowledge of the seasonality of parasite egg shedding and transmission is important for constructing parasite control programs. However, studies describing these patterns are sparse, and have largely been conducted only in the United Kingdom. This study evaluated strongylid egg shedding patterns and transmission dynamics of Strongylus vulgaris in naturally infected and untreated mares and foals through one calendar year in Kentucky, USA. The study also investigated the existence of a peri-parturient rise (PPR) in strongylid egg counts in foaling mares and collected information about Strongyloides westeri and Parascaris spp. in the foals. Methods: This study was conducted from January to December 2018. A herd of 18 mares, one stallion, and 14 foals born in 2018 were followed throughout the year. Sera and feces were collected biweekly from all horses, and worm burdens enumerated in 13 foals at necropsy. An S. vulgaris ELISA antibody test was run on all serum samples. Fecal egg counts were determined for all horses, and coproculture and qPCR assay were employed to test for the presence of S. vulgaris in the mature horses. Data were analyzed using the proc glimmix procedure in the SAS 9.4 software program. Results: We found a general lack of seasonality in strongylid egg shedding throughout the year among the mature horses, and no PPR was demonstrated. Shedding of S. vulgaris eggs displayed a higher abundance during the spring, but findings were variable and not statistically significant. Anti-S. vulgaris antibody concentrations did not display significant fluctuations in the mature horses, but evidence of passive transfer of antibodies to the foals was demonstrated, and foals assumed their own production of antibodies starting at approximately 20 weeks of age. Overall, colts shed higher numbers of strongylid, ascarid, and S. westeri eggs than fillies. Conclusions: This study demonstrated a lack of seasonality in strongylid egg shedding for the study population, which is in stark contrast to previous studies conducted elsewhere. This strongly suggests that more studies should be done investigating these patterns under different climatic conditions.
© 2022. The Author(s).
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Publication Date: 2022-02-08 PubMed ID: 35135605PubMed Central: PMC8822790DOI: 10.1186/s13071-022-05168-zGoogle Scholar: Lookup
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  • Journal Article

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 article focuses on studying the patterns of parasite egg shedding in horses, specifically strongylid egg shedding and Strongylus vulgaris transmission dynamics. It was conducted over a year in Kentucky, USA, to compare with the existing studies undertaken mostly in the UK.

Study Overview

  • The study aimed to understand the strongylid egg shedding patterns and the transmission dynamics of the parasite Strongylus vulgaris in horses over a year’s time.
  • The researchers also scrutinized the existence of a peri-parturient rise (PPR) in strongylid egg counts in foaling mares and collected data about Strongyloides westeri and Parascaris spp. in the foals.

Methodology

  • The research was carried out from January to December 2018 and involved a herd comprising of 18 mares, one stallion, and 14 foals born that year.
  • Data was collected by collecting sera and feces from the horses biweekly, and worm burdens were enumerated in 13 foals through necropsy.
  • A Strongylus vulgaris ELISA antibody test was run on all serum samples and fecal egg counts were done on all horse samples.
  • Coproculture and qPCR assay were used to test the presence of Strongylus vulgaris in the adult horses.
  • Data were analyzed using the proc glimmix procedure in the SAS 9.4 software program.

Results

  • The study found a lack of seasonality in strongylid egg shedding in the mature horses throughout the year, and there were no marked increases in strongylid egg counts around foaling.
  • The egg shedding of Strongylus vulgaris was found to be higher in spring, but the variations were inconsistent and not statistically significant.
  • Antibody concentrations against S. vulgaris did not show significant changes in the mature horses, but the study demonstrated the passive transfer of these antibodies to the foals, which started to make their own antibodies around 20 weeks of age.
  • Overall, male foals were found to shed higher numbers of strongylid, ascarid, and Strongyloides westeri eggs than female foals.

Conclusions

  • The study confirmed a lack of seasonality in strongylid egg shedding, contradicting earlier studies mostly carried out in the UK.
  • The results indicate the need for further studies under diverse climatic conditions to understand this pattern more clearly.

Cite This Article

APA
Steuer AE, Anderson HP, Shepherd T, Clark M, Scare JA, Gravatte HS, Nielsen MK. (2022). Parasite dynamics in untreated horses through one calendar year. Parasit Vectors, 15(1), 50. https://doi.org/10.1186/s13071-022-05168-z

Publication

Parasites & vectors
ISSN: 1756-3305
NlmUniqueID: 101462774
Country: England
Language: English
Volume: 15
Issue: 1
Pages: 50

Researcher Affiliations

Steuer, Ashley E
  • School of Veterinary Medicine, Texas Tech University, Amarillo, TX, USA. ashley.steuer@ttu.edu.
Anderson, Haley P
  • College of Veterinary Medicine, Auburn University, Auburn, AL, USA.
Shepherd, Taylor
  • College of Veterinary Medicine, Lincoln Memorial University, Harrogate, TN, USA.
Clark, Morgan
  • College of Veterinary Medicine, Lincoln Memorial University, Harrogate, TN, USA.
Scare, Jessica A
  • Department of Animal Science, Eastern Kentucky University, Richmond, KY, USA.
Gravatte, Holli S
  • Department of Veterinary Science, Maxwell H. Gluck Equine Research Center, University of Kentucky, Lexington, KY, USA.
Nielsen, Martin K
  • Department of Veterinary Science, Maxwell H. Gluck Equine Research Center, University of Kentucky, Lexington, KY, USA.

MeSH Terms

  • Animals
  • Anthelmintics / therapeutic use
  • Child, Preschool
  • Feces
  • Female
  • Horse Diseases / drug therapy
  • Horse Diseases / epidemiology
  • Horses
  • Humans
  • Male
  • Parasite Egg Count / veterinary
  • Parasites
  • Strongylus

Conflict of Interest Statement

All authors declare no competing interests.

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Citations

This article has been cited 8 times.
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