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Home / Equine Research Bank / Equine Vet J / Association between fungal detection, airways inflammation a...
Equine veterinary journal2025; doi: 10.1111/evj.14470

Association between fungal detection, airways inflammation and diagnosis of moderate to severe asthma in horses.

Abstract: Fungi are ubiquitous in horses' environment. Their contribution to the pathophysiology of severe asthma (SA) is acknowledged, while controversies remain for mild-moderate asthma (MA). Objective: We hypothesised that fungi are a risk factor for asthma. Our objective was to compare different combinations of analytical methods (cytology, culture) and sampling sites (tracheal wash (TW), bronchoalveolar lavage fluid (BALF)) in relation to clinical status (control, MA, SA). Methods: Prospective cross-sectional study. Methods: The study population included asymptomatic racing horses in the field and horses referred to the hospital for respiratory investigations. Fungi were detected by cytology and identified by mycology on TW and pooled BALF. Chi-square tests and multivariable logistic regressions were used for prevalence comparison between groups and association with clinical investigations. Results: In total 155 horses (85 MA, 35 SA and 35 controls) were included in the study. The overall proportions of fungal detection in TW ranged from 45.7% to 89.4% among groups. The prevalence of fungal detection in BALF was significantly lower by cytology for SA (5.7%) than MA horses (23.6%) and significantly higher by culture for MA horses (31.8%) than controls (8.6%). Fungal detection by culture in BALF was significantly associated with high tracheal mucus score, high neutrophil proportions in BALF and diagnosis of MA. Conclusions: Mycology was only performed in pooled BALF, and environment was not sampled. Conclusions: Fungi were significantly more prevalent in the airways of MA horses than SA and/or controls. Fungal detection on TW, either by cytology or culture, was uninformative in a clinical context. Fungal detection by culture, but not cytology in BALF was associated with MA.
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Publication Date: 2025-01-29 PubMed ID: 39887435DOI: 10.1111/evj.14470Google 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.

The research article explores the connection between the detection of fungi, airways inflammation, and diagnosis of moderate to severe asthma in horses. The study found that the presence of fungi in horses’ airways was significantly more common in horses with mild-to-moderate asthma compared to severe asthma or non-asthmatic horses.

Introduction and Objective

  • While it’s known that fungi present in the environment of horses can contribute to severe asthma, the role they play in the case of mild to moderate asthma remains unclear. This research hypothesizes that fungi could be a risk factor for asthma in horses.
  • The objective of this study was to compare different analytical methods and different sites within the body to assess the relation to the clinical status (mild-moderate asthma, severe asthma or control) of the horses.

Methods

  • This was a cross-sectional study examining both asymptomatic racing horses in the field along with horses referred to the hospital for respiratory investigations.
  • Fungi were detected using cytology (the study of cells) and identified using mycology (the study of fungi) applied to samples obtained from tracheal wash and bronchoalveolar lavage fluid (a technique to examine the airways and alveoli in lung).
  • Statistical tools including chi-square tests and multi-variable logistic regressions were used to compare the prevalence of fungi among different groups and to find any potential associations with the clinical condition of the horse.

Results

  • The study included 155 horses which fell into three groups: 85 with mild-moderate asthma, 35 with severe asthma, and 35 serving as controls.
  • The proportions of fungal detection in tracheal wash samples ranged from 45.7% to 89.4% among these groups.
  • The prevalence of fungal detection in bronchoalveolar lavage fluid was significantly lower for horses with severe asthma compared to those with mild-moderate asthma. Moreover, the rate of fungal detection was significantly higher in mild-moderate asthmatic horses compared to controls.
  • Fungal detection by culture in bronchoalveolar lavage fluid was significantly associated with high tracheal mucus score, high proportions of neutrophils (a type of white blood cell involved in inflammation), and diagnosis of mild-moderate asthma.

Conclusions

  • The study found that fungi were significantly more prevalent in the airways of horses with mild-moderate asthma compared to those with severe asthma or controls.
  • Fungal detection in tracheal wash, either by cytology or culture, was not informative in a clinical context.
  • However, the findings suggested that fungal detection by culture in bronchoalveolar lavage fluid was associated with mild-moderate asthma.

Cite This Article

APA
Barbazanges P, Couroucé A, Le Digarcher G, Cardwell JM, Schmitt E, Toquet MP, Lemonnier LC, Richard EA. (2025). Association between fungal detection, airways inflammation and diagnosis of moderate to severe asthma in horses. Equine Vet J. https://doi.org/10.1111/evj.14470

Publication

Equine veterinary journal
ISSN: 2042-3306
NlmUniqueID: 0173320
Country: United States
Language: English

Researcher Affiliations

Barbazanges, Pauline
  • Department of Equine Internal Medicine, Equine Clinic, ONIRIS, National College of Veterinary Medicine, Food Science and Engineering, Nantes, France.
Couroucé, Anne
  • Department of Equine Internal Medicine, Equine Clinic, ONIRIS, National College of Veterinary Medicine, Food Science and Engineering, Nantes, France.
  • Université de Caen Normandie, BIOTARGEN UR7450, Caen, France.
Le Digarcher, Gabin
  • Department of Equine Internal Medicine, Equine Clinic, ONIRIS, National College of Veterinary Medicine, Food Science and Engineering, Nantes, France.
Cardwell, Jacqueline M
  • Department of Pathobiology and Population Sciences, Royal Veterinary College, Hertfordshire, UK.
Schmitt, Eliott
  • Université de Caen Normandie, BIOTARGEN UR7450, Caen, France.
  • LABÉO (Frank Duncombe), Caen, France.
Toquet, Marie-Pierre
  • Université de Caen Normandie, BIOTARGEN UR7450, Caen, France.
  • LABÉO (Frank Duncombe), Caen, France.
Lemonnier, Louise C
  • Department of Equine Internal Medicine, Equine Clinic, ONIRIS, National College of Veterinary Medicine, Food Science and Engineering, Nantes, France.
Richard, Eric A
  • Université de Caen Normandie, BIOTARGEN UR7450, Caen, France.
  • LABÉO (Frank Duncombe), Caen, France.

Grant Funding

  • N50-2019 / Fonds Eperon
  • CS-2020-2022-028 / IFCE

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