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Equine veterinary journal2003; 35(5); 491-495; doi: 10.2746/042516403775600424

Airway inflammation and mucus in two age groups of asymptomatic well-performing sport horses.

Abstract: Horses housed in conventional stable environments are exposed to high dust loads. Long-term exposure to inhaled dust may lead to subclinical airway disease. Objective: Airway inflammation and mucus accumulation are 1) common in asymptomatic well-performing sport horses, 2) increased in older compared to younger individuals and 3) correlated. Methods: Mucus quantity and quality (endoscopic scoring) and BALF differential cytology were assessed in 13 younger horses (mean age 5 years) and 13 older horses (mean age 15 years), which had no historical or clinical evidence of lower airway disease, were performing well and were housed permanently in a conventional stable environment. Results: 1) Airway inflammation and/or mucus accumulation were very common. All sport horses showed evidence of subclinical inflammatory airway disease (IAD). 2) Older horses, having been exposed for 10 more years to a conventional stable environment, did not show increased subclinical airway inflammation or mucus accumulation. The only differences between the age groups were increased BALF total and lymphocyte cell counts in the younger horses. 3) Mucus quantity and quality scores were not significantly correlated with each other or with BALF neutrophil percentages and absolute numbers. Conclusions: Although clinically healthy and performing well, all of the examined horses housed in a conventional stable environment showed evidence of IAD. The degree of IAD was not increased in older horses that had not developed clinical signs. Conclusions: The effect of subclinical degrees of IAD on performance in dressage and show jumping should be investigated further to better understand the clinical significance of IAD in sport horses.
Publication Date: 2003-07-24 PubMed ID: 12875328DOI: 10.2746/042516403775600424Google Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't
  • Research Support
  • U.S. Gov't
  • Non-P.H.S.

Summary

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This study examined the relationship between age, exposure to traditional stables, and the presence of subclinical inflammatory airway disease (IAD) in sport horses. The researchers found that all examined horses, regardless of age, evidenced IAD. However, older horses did not display increased signs of subclinical airway inflammation or mucus accumulation.

Study Objective and Methodology

  • The study aimed to investigate whether airway inflammation and mucus build-up is common in healthy sport horses, increases with age and are correlated with each other.
  • The researchers performed endoscopic scoring to evaluate the quantity and quality of mucus. They also completed a BALF (bronchoalveolar lavage fluid) differential cytology test for the participating horses, which consisted of 13 younger horses (average age 5) and 13 older horses (average age 15).
  • All the horses were performing well and had no past or current indications of lower airway disease. They were all permanently housed in a conventional stable environment.

Results

  • The results showed that airway inflammation and/or mucus accumulation were common in all the sport horses examined, suggesting evidence of subclinical IAD.
  • Contrary to expectations, prolonged exposure (an additional 10 years in older horses) to a conventional stable environment did not result in increased subclinical airway inflammation or mucus accumulation among the older horses.
  • The researchers found that mucus quantity and quality scores were not significantly correlated with each other or with BALF neutrophil percentages and absolute numbers. The only age-related difference was higher total and lymphocyte cell counts in the BALF in younger horses.

Conclusions

  • The study concluded that all the tested horses, despite being healthy and well-performing, showed evidence of IAD. This presence of IAD did not increase in older horses, even without the appearance of evident clinical signs.
  • The authors recommended further investigations on the impact of subclinical degrees of IAD on dressage and show jumping performance to understand better the clinical significance of IAD in sport horses.

Cite This Article

APA
Gerber V, Robinson NE, Luethi S, Marti E, Wampfler B, Straub R. (2003). Airway inflammation and mucus in two age groups of asymptomatic well-performing sport horses. Equine Vet J, 35(5), 491-495. https://doi.org/10.2746/042516403775600424

Publication

ISSN: 0425-1644
NlmUniqueID: 0173320
Country: United States
Language: English
Volume: 35
Issue: 5
Pages: 491-495

Researcher Affiliations

Gerber, V
  • Pulmonary Laboratory, Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, USA.
Robinson, N E
    Luethi, S
      Marti, E
        Wampfler, B
          Straub, R

            MeSH Terms

            • Age Factors
            • Animals
            • Bronchoalveolar Lavage Fluid / cytology
            • Female
            • Flow Cytometry / veterinary
            • Horse Diseases / physiopathology
            • Horses
            • Housing, Animal
            • Inflammation / veterinary
            • Leukocyte Count / veterinary
            • Male
            • Mucus / metabolism
            • Physical Conditioning, Animal
            • Respiratory Function Tests / veterinary
            • Respiratory Tract Diseases / physiopathology
            • Respiratory Tract Diseases / veterinary
            • Sports

            Citations

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