Airway reactivity in ponies with recurrent airway obstruction (heaves).
- Comparative Study
- Journal Article
- Research Support
- Non-U.S. Gov't
- Research Support
- U.S. Gov't
- P.H.S.
Summary
This research examines the lung function and airway reactivity of two groups of ponies: those who have a record of recurrent airway obstruction (RAO or “heaves”) when kept in barns and fed hay, and a control group without history of airway obstruction. It finds that ponies in clinical remission from heaves are not overly sensitive to histamine aerosol, similar to some types of industrial asthma where heightened reactivity only occurs during acute airway obstruction.
Methodology
The scientists studied lung function and airway reactivity by applying histamine via aerosol in two groups of ponies. The ponies in the principal group had a history of recurrent airway obstruction (commonly known as ‘heaves’), especially when kept in barns and fed hay, while the control group consisted of ponies without any such history. These tests were conducted under different conditions:
- When principal ponies were at pasture and in clinical remission (period A)
- Following barn housing when principal ponies had acute airway obstruction (period B)
- After a further 1 and 2 weeks at pasture (periods C and D)
Results
The research team found that at periods A, C, and D, the dynamic compliance (Cdyn), pulmonary resistance (RL), arterial oxygen tension (PaO2), and carbon dioxide tension (PaCO2) of principal and control ponies did not differ significantly. Notably, barn housing (period B) decreased Cdyn and PaO2 and increased RL in the principal ponies, but not in the control group. This suggests that RAO conditions, specifically barn housing, does have a measurable effect on airway reactivity.
The dose of histamine needed to reduce Cdyn to 65% of the base level did not differ between principal and control ponies during periods A, C, and D. But during period B, the required histamine dose decreased by a factor of 2.5 in the principal group, indicating that the airways of ponies with heaves were more reactive during the acute phase.
The researchers did not find a correlation between changes in airway reactivity and changes in RL and Cdyn.
Conclusion
The study concluded that ponies in clinical remission from heaves are not hyperreactive to histamine aerosol, which aligns with some forms of industrial asthma where increased airway reactivity only occurs during acute episodes. The lack of correlation between histamine response and the degree of airway obstruction suggests that the heightened airway sensitivity of ponies with heaves cannot be solely attributed to alterations in baseline airway caliber. Instead, other factors such as cellular or molecular changes in the airway wall might be responsible.
Cite This Article
Publication
Researcher Affiliations
MeSH Terms
- Animals
- Bronchial Provocation Tests
- Bronchial Spasm / diagnosis
- Bronchial Spasm / veterinary
- Female
- Histamine
- Horse Diseases / diagnosis
- Horses
- Housing, Animal
- Male
- Respiratory Function Tests / veterinary
- Respiratory Hypersensitivity / diagnosis
- Respiratory Hypersensitivity / veterinary
Grant Funding
- HL-27619 / NHLBI NIH HHS
- HL-30669 / NHLBI NIH HHS
Citations
This article has been cited 13 times.- Frippiat T, Art T, Tosi I. Airway Hyperresponsiveness, but Not Bronchoalveolar Inflammatory Cytokines Profiles, Is Modified at the Subclinical Onset of Severe Equine Asthma.. Animals (Basel) 2023 Aug 1;13(15).
- Stammwitz V, Honnens Ä, Hochhuth D, Schuberth HJ. Increase of Adverse Events After Intravenous Injection of Gentamicin in Horses Between 2015 and 2017-From Marketing Authorization Holder's Point of View.. Front Vet Sci 2021;8:710571.
- Bright LA, Dittmar W, Nanduri B, McCarthy FM, Mujahid N, Costa LR, Burgess SC, Swiderski CE. Modeling the pasture-associated severe equine asthma bronchoalveolar lavage fluid proteome identifies molecular events mediating neutrophilic airway inflammation.. Vet Med (Auckl) 2019;10:43-63.
- Olave C, Morales N, Uberti B, Henriquez C, Sarmiento J, Ortloff A, Folch H, Moran G. Tamoxifen induces apoptotic neutrophil efferocytosis in horses.. Vet Res Commun 2018 Mar;42(1):57-63.
- Léguillette R, Tohver T, Bond SL, Nicol JA, McDonald KJ. Effect of Dexamethasone and Fluticasone on Airway Hyperresponsiveness in Horses With Inflammatory Airway Disease.. J Vet Intern Med 2017 Jul;31(4):1193-1201.
- Moran G, Folch H, Henriquez C, Ortloff A, Barria M. Reaginic antibodies from horses with recurrent airway obstruction produce mast cell stimulation.. Vet Res Commun 2012 Dec;36(4):251-8.
- Moran G, Buechner-Maxwell VA, Folch H, Henriquez C, Galecio JS, Perez B, Carrasco C, Barria M. Increased apoptosis of CD4 and CD8 T lymphocytes in the airways of horses with recurrent airway obstruction.. Vet Res Commun 2011 Oct;35(7):447-56.
- Morán G, Folch H, Araya O, Burgos R, Barria M. Detection of reaginic antibodies against Faenia rectivirgula from the serum of horses affected with Recurrent Airway Obstruction by an in vitro bioassay.. Vet Res Commun 2010 Dec;34(8):719-26.
- Morán G, Burgos R, Araya O, Folch H. In vitro bioassay to detect reaginic antibodies from the serum of horses affected with recurrent airway obstruction.. Vet Res Commun 2010 Jan;34(1):91-9.
- Whiting TL, Tesarowski DB. On the meaning and utility of diagnostic terms: Special reference to bronchopulmonary abnormalities in the horse.. Can Vet J 1988 Oct;29(10):787-9.
- Temelkovski J, Hogan SP, Shepherd DP, Foster PS, Kumar RK. An improved murine model of asthma: selective airway inflammation, epithelial lesions and increased methacholine responsiveness following chronic exposure to aerosolised allergen.. Thorax 1998 Oct;53(10):849-56.
- Hare JE, Viel L, Conlon PD, Marshall JS. Evaluation of an in vitro degranulation challenge procedure for equine pulmonary mast cells.. Can J Vet Res 1998 Apr;62(2):133-9.
- Doucet MY, Vrins AA, Ford-Hutchinson AW. Histamine inhalation challenge in normal horses and in horses with small airway disease.. Can J Vet Res 1991 Jul;55(3):285-93.
