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Parasitology research2024; 123(11); 394; doi: 10.1007/s00436-024-08417-5

Changes in equine strongylid communities after two decades of annual anthelmintic treatments at the farm level.

Abstract: The aim of this study was to assess the changes in strongylid communities of domestic horses after two decades of regular anthelmintic treatments; the changes in prevalence and relative abundance of individual strongylid species and their contribution to the observed alterations were estimated. The study was conducted in 2023; data collected in 2004 were used for comparison; 39 horses from two farms in Ukraine (22 horses in 2004 and 17 in 2023) were examined. In total, 18,999 strongylid specimens were collected by in vivo diagnostic deworming method before (in 2004, 9119 specimens) and after (in 2023, 9880 specimens) frequent application of anthelmintics. Strongylids were identified morphologically. Thirteen strongylid species were found in horses in 2023; only small strongylids (Cyathostominae) were recorded. In 2004, 21 species were found: 6 species of large strongylids (Strongylinae) and 15 of cyathostomins. Species richness (Margalef's index) and species diversity (Shannon's and Simpson's indexes) decreased over two decades on both farms; the Berger-Parker dominance index for C. nassatus dramatically increased up to 74.4. The dissimilarity of strongylid communities of 2023 and 2004 was primarily connected with the disappearance of large strongylids and rare cyathostomin species after two decades of regular anthelmintic treatments. SIMPER analysis revealed that C. nassatus and C. catinatum mostly contributed to this dissimilarity. A trend of gradual transformation of the strongylid community structure from multimodal (in 2004) to bimodal (in 2023) was observed on both farms.
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Publication Date: 2024-11-25 PubMed ID: 39585485PubMed Central: PMC11588933DOI: 10.1007/s00436-024-08417-5Google 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 study evaluates the shift in strongylid (a type of parasitic worm) populations in domestic horses following 20 years of regular anthelmintic (deworming) treatments, by comparing data from 2004 and 2023. The study noted a reduction in diversity of strongylid species and changes in the community structure of these parasites in horses over the two decades.

Methods and Study Setup

  • The research was conducted in 2023, using data collected in 2004 for comparison.
  • 39 horses from two farms in Ukraine were evaluated, with 22 horses in 2004 and 17 in 2023 studied separately.
  • A total of 18,999 strongylid samples were collected using an in vivo diagnostic deworming technique before and after consistent use of anthelmintics. In 2004 9119 specimens were examined and in 2023, 9880.
  • The parasites were identified morphologically for classification purposes.

Results and Observations

  • In 2023, thirteen strongylid species were found, all belonging to the smaller cyathostomins category.
  • In 2004, 21 species were identified, including six species of larger strongylids (Strongylinae) and 15 of cyathostomins.
  • The richness and diversity of species reduced over the two decades marked by the difference in Margalef’s, Shannon’s and Simpson’s indexes on both farms.
  • A significant increase of up to 74.4 in the Berger-Parker dominance index for C. nassatus, a specific cyathostomin species, was also observed.

Key Findings

  • The differences in the communities of strongylids in 2004 and 2023 were primarily linked to the extinction of larger strongylids and infrequent species of cyathostomins, linked to strict anthelmintic treatments over two decades.
  • SIMPER analysis showed that C. nassatus and C. catinatum significantly contributed to this disparity.
  • The structure of the strongylid community metamorphosed from multimodal in 2004, to bimodal in 2023 across both farms.

In general, the study offers evidence of significant changes in the parasite community within horses following the long-term use of anthelmintic treatments.

Cite This Article

APA
Kuzmina TA, Königová A, Antipov A, Kuzmin Y, Kharchenko V, Syrota Y. (2024). Changes in equine strongylid communities after two decades of annual anthelmintic treatments at the farm level. Parasitol Res, 123(11), 394. https://doi.org/10.1007/s00436-024-08417-5

Publication

Parasitology research
ISSN: 1432-1955
NlmUniqueID: 8703571
Country: Germany
Language: English
Volume: 123
Issue: 11
Pages: 394

Researcher Affiliations

Kuzmina, Tetiana A
  • Institute of Parasitology, Slovak Academy of Sciences, Hlinkova 3, Kosice, Slovakia. takuzmina@gmail.com.
  • I. I. Schmalhausen Institute of Zoology NAS of Ukraine, B. Khmelnytsky Street, 15, Kiev, Ukraine. takuzmina@gmail.com.
Königová, Alžbeta
  • Institute of Parasitology, Slovak Academy of Sciences, Hlinkova 3, Kosice, Slovakia.
Antipov, Anatoliy
  • Bila Tserkva National Agrarian University, Vul. Stavyshanska, 128, Bila Tserkva, Ukraine.
Kuzmin, Yuriy
  • I. I. Schmalhausen Institute of Zoology NAS of Ukraine, B. Khmelnytsky Street, 15, Kiev, Ukraine.
Kharchenko, Vitaliy
  • I. I. Schmalhausen Institute of Zoology NAS of Ukraine, B. Khmelnytsky Street, 15, Kiev, Ukraine.
Syrota, Yaroslav
  • Institute of Parasitology, Slovak Academy of Sciences, Hlinkova 3, Kosice, Slovakia.
  • I. I. Schmalhausen Institute of Zoology NAS of Ukraine, B. Khmelnytsky Street, 15, Kiev, Ukraine.

MeSH Terms

  • Animals
  • Horses / parasitology
  • Anthelmintics / administration & dosage
  • Anthelmintics / therapeutic use
  • Ukraine
  • Farms
  • Horse Diseases / parasitology
  • Horse Diseases / drug therapy
  • Strongylida Infections / veterinary
  • Strongylida Infections / drug therapy
  • Strongylida Infections / parasitology
  • Strongylida Infections / epidemiology
  • Prevalence
  • Strongyloidea / drug effects
  • Strongyloidea / classification
  • Strongyloidea / isolation & purification
  • Biodiversity

Grant Funding

  • projects No. 09I03-03-V01-00015 and No. 09I03-03-V01-00046 / EU NextGenerationEU through the Recovery and Resilience Plan for Slovakia
  • projects No. 09I03-03-V01-00015 and No. 09I03-03-V01-00046 / EU NextGenerationEU through the Recovery and Resilience Plan for Slovakia

Conflict of Interest Statement

Declarations. Ethics approval and consent to participate: All national and institutional guidelines for the care and use of animals were followed. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests.

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