- Respiratory tract infections such as equine influenza and equine herpes virus infection
- Upper respiratory diseases and conditions:
- Pharyngeal lymphoid hyperplasia (pharyngitis)
- Dorsal displacement of the soft palate
- Nasopharyngeal collapse
- Laryngeal hemiplegia (roaring)
- Epiglottic entrapment
- Arytenoid chondritis
- Nasopharyngeal cicatrix
- Lower respiratory diseases and conditions:
- Equine asthma syndrome: an umbrella term to describe chronic non-infectious inflammatory diseases affecting the lower airway in horses
- Previous terminology includes heaves, inflammatory airway disease (IAD), recurrent airway obstruction (RAO), chronic obstructive pulmonary disease (COPD) and broken wind
- Equine asthma syndrome can be further sub-classified based on the disease severity into mild-moderate equine asthma (the disease formerly known as IAD) and severe equine asthma (formerly known as RAO).
- Severe equine asthma can be either barn-associated or summer pasture-associated
- Exercise-induced pulmonary hemorrhage (EIPH)
- Bacterial, viral, and fungal pneumonias
- Equine asthma syndrome: an umbrella term to describe chronic non-infectious inflammatory diseases affecting the lower airway in horses