Seasonal recurrent airway obstruction

Veterinary advice should be sought before applying any treatment or vaccine.

Seasonal Recurrent Airway Obstruction

Summer Pasture-associated Obstructive Pulmonary Disease

Seasonal recurrent airway obstruction, also known as summer pasture-associated recurrent airway obstruction (SPA-RAO), is a seasonal airway obstructive disease of horses, characterized by clinical exacerbation after exposure to pasture during the summer. Clinical signs usually present in horses during exposure to pastures during turnout in the late spring the summer, although some horses don't develop signs until late summer or early fall. Certain mold spores, grass pollens, and species of grass trigger onset of the disease.

Symptoms

Exercise intolerance
Labored expiratory effort
93%
Abnormal respiratory sounds
93%
Coughing
90%
Flared nostrils
85%
Lethargy
25%
Loss of appetite
25%

Diagnosis

  • History
  • Clinical signs
  • Physical exam
  • Endoscopy
  • Tracheal aspirate
  • BAL

Treatment


TreatmentDetails
Medical therapySystemic dexamethasone or oral prednisolone in combination with clenbuterol
Management changesIncrease time spent in stall or ideally in a lower-dust pasture environment.
Diet changesLow-dust feed and regularly soaking hay
Bedding changeUsing a low-dust bedding such as quality wood shavings, rubber mats, rice hulls or shredded newspaper.

Prevention

  • Minimizing dust exposure

Scientific Research References

Good Overviews

Risk Factors

  • Living in the Southeastern U.S., especially Florida, Georgia, Louisiana and Mississippi

Seasonality

WinterSpringSummerAutumn

Also Consider