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Home / Equine Research Bank / Anim Genet / Association of inbreeding and regional equine leucocyte anti...
Animal genetics2021; 52(4); 422-430; doi: 10.1111/age.13075

Association of inbreeding and regional equine leucocyte antigen homozygosity with the prevalence of insect bite hypersensitivity in Old Kladruber horse.

Abstract: Inbreeding depression is the reduction of performance caused by mating of close relatives. In livestock populations, inbreeding depression has been traditionally estimated by regression of phenotypes on pedigree inbreeding coefficients. This estimation can be improved by utilising genomic inbreeding coefficients. Here we estimate inbreeding depression for insect bite hypersensitivity (IBH) prevalence, the most common allergic horse disease worldwide, in Old Kladruber horse. In a deep pedigree with 3214 horses (187 genotyped), we used a generalised linear mixed model with IBH phenotype from 558 horses examined between 1996 and 2009 (1368 records). In addition to the classical pedigree information, we used the single-step approach that enabled joint use of pedigree and genomic information to estimate inbreeding depression overall genome and equine leucocyte antigen (ELA) class II region. Significant inbreeding depression was observed in all models fitting overall inbreeding coefficients (odds ratio between 1.018 and 1.074, P < 0.05) with the exception of Kalinowski's new inbreeding (P = 0.0516). The increase of ELA class II inbreeding was significantly associated with increased prevalence of IBH (odds ratio 1.018; P = 0.027). However, when fitted jointly with the overall inbreeding coefficient, the effect of ELA class II inbreeding was not significant (odds ratio 1.016; P = 0.062). Overall, the higher ELA class II and/or overall inbreeding (pedigree or genomic) was associated with increased prevalence of IBH in Old Kladruber horses. The single-step approach provides an efficient use of all the available pedigree, genomic, and phenotype information for estimation of overall and regional inbreeding effects.
© 2021 The Authors. Animal Genetics published by John Wiley & Sons Ltd on behalf of Stichting International Foundation for Animal Genetics.
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Publication Date: 2021-05-10 PubMed ID: 33970495PubMed Central: PMC8360196DOI: 10.1111/age.13075Google Scholar: Lookup
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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.

This research study explores the impact of inbreeding and certain genetic factors on the prevalence of insect bite hypersensitivity (IBH), a common allergic disease in horses, in Old Kladruber horses specifically. The research found that an increased level of inbreeding and regional equine leucocyte antigen (ELA) class II homozygosity can elevate the risk of IBH.

Objective of the Research

  • The research aimed to evaluate if inbreeding and a specific genetic trait, i.e., equine leucocyte antigen (ELA) class II homozygosity, have an impact on the prevalence of insect bite hypersensitivity (IBH) among Old Kladruber horses. IBH is known as the most pervasive allergic disease among horses.

Methodology

  • A vast pedigree of 3214 Old Kladruber horses was leveraged for the research, of which 187 were genotyped. The study used a generalized linear mixed model using the IBH phenotype derived from an examination of 558 horses, comprising 1368 records, conducted between 1996 and 2009.
  • In addition to using the classical pedigree information, a single-step approach was implemented. This approach enabled the researchers to use both the pedigree and genomic information simultaneously to estimate inbreeding depression across the overall genome and specifically within the ELA class II region.

Findings

  • A significant degree of inbreeding depression was observed in all models that were fitting overall inbreeding coefficients. The only exception to this was the model using Kalinowski’s new inbreeding.
  • The study found a significant association between an increase of ELA class II inbreeding and a higher prevalence of IBH. However, when fitted jointly with the overall inbreeding coefficient, the effect of ELA class II inbreeding was not significant.
  • In general, it was found that a higher level of ELA class II and/or overall inbreeding (either pedigree or genomic) was associated with an increased prevalence of IBH in Old Kladruber horses.

Conclusion

  • The research concluded that the single-step approach is an efficient method to use all available pedigree, genomic, and phenotype information to estimate the impact of overall and regional inbreeding.
  • The findings from the study can potentially aid in understanding and mitigating the prevalence of IBH in specific horse populations by considering genetic factors related to inbreeding and ELA class II.

Cite This Article

APA
Vostry L, Vostra-Vydrova H, Citek J, Gorjanc G, Curik I. (2021). Association of inbreeding and regional equine leucocyte antigen homozygosity with the prevalence of insect bite hypersensitivity in Old Kladruber horse. Anim Genet, 52(4), 422-430. https://doi.org/10.1111/age.13075

Publication

Animal genetics
ISSN: 1365-2052
NlmUniqueID: 8605704
Country: England
Language: English
Volume: 52
Issue: 4
Pages: 422-430

Researcher Affiliations

Vostry, L
  • Czech University of Life Sciences, Kamycka 129, Prague, 16500, Czech Republic.
Vostra-Vydrova, H
  • Czech University of Life Sciences, Kamycka 129, Prague, 16500, Czech Republic.
  • Institute of Animal Science, Pratelstvi 815, Prague, 10400, Czech Republic.
Citek, J
  • South Bohemia University, Branisovska 31a, Ceske Budejovice, 370 05, Czech Republic.
  • Veterinary Research Institute, Hudcova 296/70, Brno, 621 00, Czech Republic.
Gorjanc, G
  • The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Edinburgh, Midlothian, EH259RG, UK.
Curik, I
  • Faculty of Agriculture, University of Zagreb, Svetošimunska cesta 25, Zagreb, 10000, Croatia.

MeSH Terms

  • Animals
  • Czech Republic / epidemiology
  • Female
  • Histocompatibility Antigens Class I / genetics
  • Horse Diseases / epidemiology
  • Horse Diseases / genetics
  • Horse Diseases / immunology
  • Horses
  • Hypersensitivity / epidemiology
  • Hypersensitivity / genetics
  • Hypersensitivity / immunology
  • Hypersensitivity / veterinary
  • Inbreeding
  • Insect Bites and Stings / complications
  • Male
  • Prevalence

Grant Funding

  • QK1910156 / Ministry of Agriculture of the Czech Republic
  • MZE-RO0719 / Ministry of Agriculture of the Czech Republic
  • QK1910320 / Ministry of Agriculture of the Czech Republic
  • ANAGRAMS-IP-2018-01-8708 / Croatian Science Foundation
  • BBS/E/D/30002275 / BBSRC to The Roslin Institute
  • The University Of Edinburgh's Data-Driven Innovation Chancellor's Fellowship

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Citations

This article has been cited 2 times.
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