Pulmonary eosinophilia associated with increased airway responsiveness in young racing horses.
Abstract: Horses are known to acquire small airway disease (SAD), an allergen-induced naturally occurring syndrome of reversible obstructive lung disease accompanied by airway hyperresponsiveness and increased inflammatory cell numbers on bronchoalveolar lavage (BAL). This disorder has received scant attention in young racehorses. The purpose of the present report was to examine the effect of BAL eosinophilia in young racehorses on clinical examination, BAL, hematology, airway responsiveness, and on pulmonary function at rest and after a standardized exercise challenge. Five (3 males, 2 females; age 2.6 +/- 0.9 years) with a history of respiratory compromise and BAL eosinophil differential count > 5% and 6 controls (4 males, 2 females; age 3.5 +/- 1.0 years) training and performing to expectation with normal BAL cell differential (eosinophils < 1%) were studied. Respiratory system clinical examination was performed and expressed as a clinical score. Arterial blood gas measurements, CBC, and pulmonary function testing were performed at rest. Pulmonary mechanics measurements were repeated 1 hour and 20 hours after a standardized treadmill exercise challenge. Incremental histamine inhalation challenge was performed and the concentration of histamine effecting a 35% decrease in dynamic compliance (PC35CDyn) was determined. Significant differences were noted between and controls with regard to clinical score (P = .01), blood eosinophils (P = .04), BAL cell count (P = .04), BAL macrophage differential (P = .04), PC35CDyn (P = .008), and tidal volume and respiratory rate at 20 hours following exercise challenge (P = .05). We conclude that pulmonary eosinophilia and airway hyperresponsiveness are manifest in some young horses without overt airway obstruction at rest. We speculate that these may be early events in the natural progression of heaves.
Publication Date: 1998-05-22 PubMed ID: 9595377DOI: 10.1111/j.1939-1676.1998.tb02112.xGoogle Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
- Research Support
- Non-U.S. Gov't
- Airway Disease
- Allergies
- Bronchoalveolar Lavage
- Clinical Examination
- Clinical Findings
- Clinical Pathology
- Clinical Study
- Equine Diseases
- Equine Health
- Exercise Physiology
- Hematology
- Histamine
- Horses
- Inflammation
- Pulmonary Health
- Respiratory Disease
- Treadmill Exercise
- Veterinary Medicine
- Veterinary Research
- Young Horses
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 study analyzes small airway disease (SAD) in young racing horses, with particular focus on the effects of eosinophilia (a condition characterized by abnormal increase of eosinophils in the body) in the bronchoalveolar lavage area. The results indicate a correlation between eosinophilia and increased airway responsiveness, suggesting that these might be early signs of heaves, a chronic, non-infectious airway condition.
Objective of the Research
- This research aimed to understand the effect of bronchoalveolar lavage (BAL) eosinophilia in young racing horses, examining various factors like clinical examination, BAL, hematology, airway responsiveness, and pulmonary function at rest and after a standard exercise challenge.
Research Methodology
- The sample consisted of eleven horses, five with a history of respiratory issues and an eosinophil differential count above 5%, and six healthy controls training and performing as expected with normal BAL cell differential (eosinophils less than 1%).
- Various tests were conducted, including clinical examination, arterial blood gas measurements, Complete Blood Count (CBC), pulmonary function testing at rest, pulmonary mechanics measurements post-exercise, and a histamine inhalation challenge test to determine the PC35CDyn—the concentration of histamine triggering a 35% decrease in dynamic compliance.
Findings of the Study
- The research found significant differences between the controls and horses with eosinophilia concerning clinical score, blood eosinophils, BAL cell count, BAL macrophage differential, PC35CDyn, and tidal volume and respiratory rate 20 hours following the exercise challenge.
- These results imply that eosinophilia and airway hyperresponsiveness occur in young horses without apparent airway obstruction when at rest.
- The study concludes that these signs might imply early indicators of heaves, a common condition in sports horses characterized by difficulty in breathing.
Implication of the Study
- This study emphasizes the importance of regular monitoring and early detection of BAL eosinophilia in young racehorses as it can be an early sign of the potential progression to heaves.
- Understanding the correlation between eosinophilia and increased airway responsiveness can help form new strategies for preventing and treating heaves in horses.
Cite This Article
APA
Hare JE, Viel L.
(1998).
Pulmonary eosinophilia associated with increased airway responsiveness in young racing horses.
J Vet Intern Med, 12(3), 163-170.
https://doi.org/10.1111/j.1939-1676.1998.tb02112.x Publication
Researcher Affiliations
- Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Canada.
MeSH Terms
- Animals
- Bronchoalveolar Lavage Fluid / cytology
- Eosinophilia / physiopathology
- Eosinophilia / veterinary
- Exercise Test / veterinary
- Female
- Histamine
- Horse Diseases
- Horses
- Lung Diseases / physiopathology
- Lung Diseases / veterinary
- Male
- Physical Conditioning, Animal
- Physical Endurance
- Respiration
- Respiratory Function Tests / veterinary
Citations
This article has been cited 12 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).
- Dixon CE, Bedenice D, Mazan MR. Comparison of Flowmetric Plethysmography and Forced Oscillatory Mechanics to Measure Airway Hyperresponsiveness in Horses.. Front Vet Sci 2020;7:511023.
- Brankston G, Greer AL, Marshall Q, Lang B, Moore K, Hodgins D, Hennessey JTG, Beeler-Marfisi J. Increased Weekly Mean PM(2.5), and NO(2) Are Associated With Increased Proportions of Lower Airway Granulocytes in Ontario Horses.. Front Vet Sci 2020;7:185.
- Davis KU, Sheats MK. Bronchoalveolar Lavage Cytology Characteristics and Seasonal Changes in a Herd of Pastured Teaching Horses.. Front Vet Sci 2019;6:74.
- Bond S, Léguillette R, Richard EA, Couetil L, Lavoie JP, Martin JG, Pirie RS. Equine asthma: Integrative biologic relevance of a recently proposed nomenclature.. J Vet Intern Med 2018 Nov;32(6):2088-2098.
- Ivester KM, Couëtil LL, Moore GE. An observational study of environmental exposures, airway cytology, and performance in racing thoroughbreds.. J Vet Intern Med 2018 Sep;32(5):1754-1762.
- 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.
- Barton AK, Gehlen H. Pulmonary Remodeling in Equine Asthma: What Do We Know about Mediators of Inflammation in the Horse?. Mediators Inflamm 2016;2016:5693205.
- Couëtil LL, Cardwell JM, Gerber V, Lavoie JP, Léguillette R, Richard EA. Inflammatory Airway Disease of Horses--Revised Consensus Statement.. J Vet Intern Med 2016 Mar-Apr;30(2):503-15.
- Ivester KM, Couëtil LL, Zimmerman NJ. Investigating the link between particulate exposure and airway inflammation in the horse.. J Vet Intern Med 2014 Nov-Dec;28(6):1653-65.
- Richard EA, Depecker M, Defontis M, Leleu C, Fortier G, Pitel PH, Couroucé-Malblanc A. Cytokine concentrations in bronchoalveolar lavage fluid from horses with neutrophilic inflammatory airway disease.. J Vet Intern Med 2014 Nov-Dec;28(6):1838-44.
- Ivester KM, Couëtil LL, Moore GE, Zimmerman NJ, Raskin RE. Environmental exposures and airway inflammation in young thoroughbred horses.. J Vet Intern Med 2014 May-Jun;28(3):918-24.
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
