Background: Racehorses may experience exercise-induced bronchodilation or bronchoconstriction, with potential differences between healthy and asthmatic individuals. Objectives: To identify exercise-related lung function variations by oscillometry in racehorses, compare lung function between healthy and mild equine asthma (MEA) horses, assess oscillometry's potential as a predictor of racing fitness. Study design: Prospective case–control clinical study. Methods: Fourteen Thoroughbred racehorses (5 healthy, 9 MEA) underwent a protocol including respiratory oscillometry at rest, exercise with fitness monitoring, oscillometry at 15 and 45 min post-exercise, and bronchoalveolar lavage fluid (BALf) cytology. Oscillometry parameters (resistance [Rrs] and reactance [Xrs]) were compared within and between healthy and MEA groups at different timepoints. Associations between Rrs and Xrs at rest and 15 min post-exercise and BALf cytology and fitness indices were evaluated. Results: MEA horses showed higher Rrs at 15 min post-exercise (0.6 ± 0.2 cmH2O/L/s) than healthy horses (0.3 ± 0.1 cmH2O/L/s) (p < 0.01). In healthy horses, Rrs decreased at 15 min post-exercise compared with resting values (0.5 ± 0.1 cmH2O/L/s) (p = 0.04). In MEA horses, oscillometry parameters did not vary with time. Post-exercise Xrs inversely correlated with total haemosiderin score (p < 0.01, r2 = 0.51). Resting Rrs inversely correlated with speed at 200 bpm (p = 0.03, r2 = −0.61), and Xrs with maximum heart rate (HR) during exercise (p = 0.02, r2 = −0.62). Post-exercise Rrs inversely correlated with mean (p = 0.04, r2 = −0.60) and maximum speed (p = 0.04, r2 = −0.60), and HR variability (p < 0.01, r2 = −0.74). Main limitations: Small sample size, oscillometry repeatability not assessed, potential interference of upper airway obstructions, external variables influencing fitness indices. Conclusions: Oscillometry identified lung function differences between healthy and MEA horses at 15 min post-exercise. Only healthy horses exhibited exercise-induced bronchodilation. Oscillometry showed potential in predicting subclinical airway obstruction.

Respiratory oscillometry testing in relation to exercise in healthy and asthmatic Thoroughbreds / Lo Feudo, C. M.; Stucchi, L.; Bizzotto, D.; Dellaca, R.; Lavoie, J. -P.; Ferrucci, F.. - In: EQUINE VETERINARY JOURNAL. - ISSN 0425-1644. - (2024). [10.1111/evj.14065]

Respiratory oscillometry testing in relation to exercise in healthy and asthmatic Thoroughbreds

Stucchi L.
;
2024-01-01

Abstract

Background: Racehorses may experience exercise-induced bronchodilation or bronchoconstriction, with potential differences between healthy and asthmatic individuals. Objectives: To identify exercise-related lung function variations by oscillometry in racehorses, compare lung function between healthy and mild equine asthma (MEA) horses, assess oscillometry's potential as a predictor of racing fitness. Study design: Prospective case–control clinical study. Methods: Fourteen Thoroughbred racehorses (5 healthy, 9 MEA) underwent a protocol including respiratory oscillometry at rest, exercise with fitness monitoring, oscillometry at 15 and 45 min post-exercise, and bronchoalveolar lavage fluid (BALf) cytology. Oscillometry parameters (resistance [Rrs] and reactance [Xrs]) were compared within and between healthy and MEA groups at different timepoints. Associations between Rrs and Xrs at rest and 15 min post-exercise and BALf cytology and fitness indices were evaluated. Results: MEA horses showed higher Rrs at 15 min post-exercise (0.6 ± 0.2 cmH2O/L/s) than healthy horses (0.3 ± 0.1 cmH2O/L/s) (p < 0.01). In healthy horses, Rrs decreased at 15 min post-exercise compared with resting values (0.5 ± 0.1 cmH2O/L/s) (p = 0.04). In MEA horses, oscillometry parameters did not vary with time. Post-exercise Xrs inversely correlated with total haemosiderin score (p < 0.01, r2 = 0.51). Resting Rrs inversely correlated with speed at 200 bpm (p = 0.03, r2 = −0.61), and Xrs with maximum heart rate (HR) during exercise (p = 0.02, r2 = −0.62). Post-exercise Rrs inversely correlated with mean (p = 0.04, r2 = −0.60) and maximum speed (p = 0.04, r2 = −0.60), and HR variability (p < 0.01, r2 = −0.74). Main limitations: Small sample size, oscillometry repeatability not assessed, potential interference of upper airway obstructions, external variables influencing fitness indices. Conclusions: Oscillometry identified lung function differences between healthy and MEA horses at 15 min post-exercise. Only healthy horses exhibited exercise-induced bronchodilation. Oscillometry showed potential in predicting subclinical airway obstruction.
2024
Respiratory oscillometry testing in relation to exercise in healthy and asthmatic Thoroughbreds / Lo Feudo, C. M.; Stucchi, L.; Bizzotto, D.; Dellaca, R.; Lavoie, J. -P.; Ferrucci, F.. - In: EQUINE VETERINARY JOURNAL. - ISSN 0425-1644. - (2024). [10.1111/evj.14065]
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11388/326655
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 0
  • ???jsp.display-item.citation.isi??? 0
social impact