Summer eczema in exported Icelandic horses: influence of environmental and genetic factors.
Abstract: A cross sectional study was designed to estimate the prevalence of summer eczema (a chronic, recurrent seasonal dermatitis) in exported Icelandic horses and the influence of environmental and genetic factors on the development of the disease. Among 330 horses, which had been exported to Germany, Denmark and Sweden, 114 (34.5%) were found to have clinical signs of summer eczema. The prevalence was highest 2 years after export and the exposure to the biting midges Culicoides spp., was found to be the main risk factor for developing the disease. Genetic influence on the sensitivity for the disease was not established. It was concluded that exported Icelandic horses are predisposed for summer dermatitis and the fact that they are not introduced to the antigens of the biting midges early in live, due to it's absence in Iceland, is likely to explain the high prevalence of the disease after export.
Publication Date: 2006-05-26 PubMed ID: 16987399PubMed Central: PMC1513129DOI: 10.1186/1751-0147-48-3Google Scholar: Lookup
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- Comparative Study
- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
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This study investigates the prevalence of summer eczema—a chronic, recurring skin disease—in exported Icelandic horses, and how environmental and genetic factors may affect the disease. The study found a high rate of summer eczema among 330 Icelandic horses sent to Germany, Denmark, and Sweden, with exposure to biting midges identified as a significant risk. The influence of genetics on the disease was not confirmed.
Summary of the Research
- The researchers conducted a cross-sectional study to determine the prevalence of summer eczema—a recurrent type of dermatitis that often worsens seasonally—in Icelandic horses exported to Germany, Denmark, and Sweden.
- Summer eczema was observed in 114 out of 330 exported horses, accounting for 34.5% of the group. The occurrence of the disease was the greatest two years post-exportation.
Role of Environmental and Genetic Factors
- The primary risk factor for the development of summer eczema in these horses was exposure to biting midges of the genus Culicoides. These insects are prevalent in the environments the horses were sent to, but are absent in the horses’ native Iceland.
- From the study, the researchers were unable to determine a clear genetic influence on the sensitivity towards the disease.
Conclusions of the Study
- The demonstrated prevalence of summer eczema in Icelandic horses shipped overseas points towards a predisposition among these animals for the dermatitis.
- The researchers speculate that the high prevalence of the disease in exported horses can be explained by their lack of exposure to Culicoides antigens early on in life, considering these insects do not exist in Iceland. The horses’ immune systems, therefore, may not have had the opportunity to develop a response to these antigens, making them more susceptible to summer eczema post-exportation.
Cite This Article
APA
Björnsdóttir S, Sigvaldadóttir J, Broström H, Langvad B, Sigurdsson A.
(2006).
Summer eczema in exported Icelandic horses: influence of environmental and genetic factors.
Acta Vet Scand, 48(1), 3.
https://doi.org/10.1186/1751-0147-48-3 Publication
Researcher Affiliations
- Icelandic Veterinary Services, Dept Holar, 551 Saudarkrokur, Iceland. systa@holar.is
MeSH Terms
- Age Factors
- Animals
- Ceratopogonidae / immunology
- Cross-Sectional Studies
- Denmark / epidemiology
- Eczema / epidemiology
- Eczema / genetics
- Eczema / veterinary
- Environment
- Female
- Germany / epidemiology
- Horse Diseases / epidemiology
- Horse Diseases / genetics
- Horses
- Iceland
- Male
- Prevalence
- Risk Factors
- Surveys and Questionnaires
- Sweden / epidemiology
- Time Factors
References
This article includes 18 references
Citations
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