PloS one2018; 13(12); e0207871; doi: 10.1371/journal.pone.0207871

Lower allergen levels in hypoallergenic Curly Horses? A comparison among breeds by measurements of horse allergens in hair and air samples.

Abstract: Exposure to horses can cause severe allergic reactions in sensitized individuals. The breed, American Bashkir Curly Horse is categorized as hypoallergenic, primarily due to reports of allergic patients experiencing fewer symptoms while handling this special breed. The possible reasons for this phenomenon could be lower allergen production and/or reduced allergen release into the air because of increased sebum content in their skin and hair compared to other breeds. Therefore, the aim of the current study was to compare different horse breeds in relation to allergen content in hair and airborne dust samples. In total, 224 hair samples from 32 different horse breeds were investigated. Personal nasal filters were used to collect airborne dust during the grooming of 20 Curly Horses and 20 Quarter Horses. Quantitative analysis of all samples was performed using two newly developed immunoassays for the detection of horse dander (HD) antigens and the major allergen Equ c 1 and the commercial assay for Equ c 4. Results were analyzed using multiple linear regression models for hair samples and the Mann Whitney U test for airborne samples. Horse antigen and allergen levels differed up to four orders of magnitude between individual animals. Despite enormous variability, levels of HD antigen, Equ c 1 and Equ c 4 in hair were significantly related to the breed and gender combined with the castration status of male animals. Curly Horses had significantly higher concentrations of all three tested parameters compared to the majority of the investigated breeds (medians: 11800 μg/g for HD antigen, 2400 μg/g for Equ c 1, and 258 kU/g for Equ c 4). Tinker Horses, Icelandic Horses and Shetland Ponies were associated with approximately 7-fold reduced levels of HD antigen and Equ c 1, and up to 25-fold reduced levels of Equ c 4 compared to Curly Horses. Compared to mares, stallions displayed increased concentrations of HD antigens, Equ c 1 and Equ c 4 by a factor 2.2, 3.5 and 6.7, respectively. No difference was observed between mares and geldings. No differences in airborne allergen concentrations collected with personal nasal filters during grooming were found between Curly and Quarter Horses. Breed and castration status had a significant influence on the antigen and allergen levels of horse hair. However, these differences were smaller than the wide variability observed among individual horses. Compared to other breeds, Curly Horses were not associated with lower allergen levels in hair and in air samples collected during grooming. Our approach provides no molecular explanation why Curly Horses are considered to be hypoallergenic.
Publication Date: 2018-12-12 PubMed ID: 30540798PubMed Central: PMC6291085DOI: 10.1371/journal.pone.0207871Google Scholar: Lookup
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  • Journal Article

Summary

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This research study explores allergen levels in various horse breeds, with a particular emphasis on the hypoallergenic Curly Horse breed. Despite the belief that Curly Horses produce less allergens, the research did not find any significant differences in allergen content when compared to other breeds.

Research Goal

The researchers were trying to find out if Curly Horses, a breed considered hypoallergenic due to anecdotal evidence of allergy sufferers reacting less to them, actually possess lower allergen levels compared to other horse breeds. They also wanted to determine if there were any differences in the amount of allergens released into the air during grooming.

Methodology

The researchers chose two methods to gather data:

  • They collected hair samples from 224 horses, representing 32 different breeds, to measure allergen content in their fur. Specifically, they were searching for two particular antigens, Equ c 1 and Equ c 4.
  • To measure the allergens released into the air, personal nasal filters were used while grooming 20 Curly Horses and 20 Quarter Horses.

Research Findings

The results of their findings were distinct for each method used:

  • They found a wide range in antigen and allergen levels in the hair samples with differences reaching up to four orders of magnitude between individual animals.
  • It was found that the breed and gender (and castration status in males) significantly affected the levels of allergens in hair samples, with Curly horses having higher concentrations of all three tested parameters (HD antigen, Equ c 1 and Equ c 4) compared to most of the other breeds.
  • Contrary to expectations, breeds such as Tinker Horses, Icelandic Horses, and Shetland Ponies showed significantly lower allergen levels than the supposedly hypoallergenic Curly Horses.
  • In terms of airborne allergen concentrations, there was no observable difference during grooming between Curly and Quarter Horses.

Conclusion

In conclusion, the researchers discovered that Curly Horses, while believed to be hypoallergenic, did not show lower allergen levels either in their hair or in airborne samples collected during grooming. Other factors aside from the breed, like gender and castration status, had a significant effect on antigen and allergen levels. However, these differences were relatively small compared to the wide range of allergen levels found between individual horses. The findings didn’t provide any molecular explanation as to why Curly Horses are considered hypoallergenic. Hence, more research is required in this area.

Cite This Article

APA
Zahradnik E, Janssen-Weets B, Sander I, Kendzia B, Mitlehner W, May C, Raulf M. (2018). Lower allergen levels in hypoallergenic Curly Horses? A comparison among breeds by measurements of horse allergens in hair and air samples. PLoS One, 13(12), e0207871. https://doi.org/10.1371/journal.pone.0207871

Publication

ISSN: 1932-6203
NlmUniqueID: 101285081
Country: United States
Language: English
Volume: 13
Issue: 12
Pages: e0207871
PII: e0207871

Researcher Affiliations

Zahradnik, Eva
  • Institute for Prevention and Occupational Medicine of the German Social Accident Insurance, Institute of the Ruhr-Universitu00e4t Bochum (IPA), Bochum, Germany.
Janssen-Weets, Bente
  • Institute for Prevention and Occupational Medicine of the German Social Accident Insurance, Institute of the Ruhr-Universitu00e4t Bochum (IPA), Bochum, Germany.
  • Luxemburg Institute of Health, Esch-sur-Alzette, Luxemburg.
Sander, Ingrid
  • Institute for Prevention and Occupational Medicine of the German Social Accident Insurance, Institute of the Ruhr-Universitu00e4t Bochum (IPA), Bochum, Germany.
Kendzia, Benjamin
  • Institute for Prevention and Occupational Medicine of the German Social Accident Insurance, Institute of the Ruhr-Universitu00e4t Bochum (IPA), Bochum, Germany.
Mitlehner, Wolfgang
  • Private Medical Practice Pneumology, Internal Medicine, Allergology, Klappholz, Germany.
May, Caroline
  • Medizinisches Proteom-Center (MPC), Ruhr-Universitu00e4t Bochum, Bochum, Germany.
Raulf, Monika
  • Institute for Prevention and Occupational Medicine of the German Social Accident Insurance, Institute of the Ruhr-Universitu00e4t Bochum (IPA), Bochum, Germany.

MeSH Terms

  • Allergens / analysis
  • Animals
  • Breeding
  • Dust
  • Female
  • Hair
  • Horses / immunology
  • Humans
  • Hypersensitivity
  • Male

Conflict of Interest Statement

The authors have declared that no competing interests exist.

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Citations

This article has been cited 3 times.
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