Effects of changes to the stable environment on the exhalation of ethane, carbon monoxide and hydrogen peroxide by horses with respiratory inflammation.
Authors: Wyse C A, Skeldon K, Hotchkiss J W, Gibson G, Yam P S, Christley R M, Preston T, Cumming D R S, Padgett M, Cooper J C, Love S
Journal: The Veterinary record
Summary
# Editorial Summary Recurrent airway obstruction (RAO) remains a significant welfare and performance concern in stabled horses, with environmental dust exposure implicated as a major trigger; this study examined whether measurable biomarkers of respiratory inflammation respond to changes in stable management by monitoring six RAO-affected horses across two fortnight periods—one using conventional straw bedding with hay, the other employing paper bedding and ensiled forage in a crossover design. Exhaled ethane and carbon monoxide were quantified every three days alongside daily clinical observations of nasal discharge and cough, revealing that the reduced-dust regimen produced both fewer clinical signs and significantly lower levels of these volatile organic compounds. Whilst exhaled hydrogen peroxide from breath condensate showed no response to management changes, the correlation between ethane/carbon monoxide levels and clinical inflammation markers suggests these exhaled gases offer objective, non-invasive indices of airway status. For practitioners managing RAO cases, these findings reinforce the evidence base for dust-reducing bedding and forage strategies, whilst the gas biomarkers potentially provide a measurable way to assess individual horses' responses to environmental modifications—a tool that could refine management protocols beyond reliance on visible clinical signs alone.
Read the full abstract on PubMed
Practical Takeaways
- •Switching horses with recurrent airway obstruction to paper bedding and ensiled forage can reduce visible signs of respiratory disease (nasal discharge and cough)
- •Exhaled ethane and CO levels may serve as useful biomarkers for monitoring respiratory inflammation response to environmental management changes in affected horses
- •Environmental dust reduction appears more effective than hydrogen peroxide measurements alone for assessing management efficacy in horses with airway inflammation
Key Findings
- •Reduced-dust regimen (paper bedding and ensiled grass) produced fewer clinical signs of airway inflammation compared to conventional straw bedding and hay management
- •Exhaled ethane and carbon monoxide were significantly lower on the reduced-dust regimen and correlated with clinical respiratory inflammation signs
- •Exhaled hydrogen peroxide was not affected by management regimen changes despite clinical improvements