The respiratory system includes the nasal passages, sinsuses, guttural pouches, trachea (wind pipe), larynx (voice box) and lungs. Clinical symptoms of problems associated with the respiratory system can range from nasal discharge, cough and wheezing to subtle noise at intense exercise and poor performance.
Problems affecting the lower airway (lungs) can include COPD or RAO (recurrent airway obstruction), now called equine asthma. This is a chronic problem where your horse develops allergies to certain particles inhaled in the air. These can be multiple but can especially be associated with certain hay or bedding. Most commonly horses suffering from equine asthma will exhibit signs of chronic respiratory disease, e.g. raised respiratory rates and intermittent coughing. Occasionally, exposure to these allergens can result in a very severe reaction where the horse will suffer from a sudden onset respiratory distress.
Diagnosis of equine asthma, and many other airway problems is made via passing an endoscope down the trachea and taking samples from the fluid in the trachea and from the lungs. These samples can then be assessed under the microscope to look at the cells present and determine the nature of the problem.
Endoscopy can also be used to investigate sinus or guttural pouch disease (such as strangles); or perform a dynamic airway assessment. When horses make loud respiratory noises when exercised, e.g. whistling or roaring, scoping will help to find out why. The larynx can be assessed to check it is functioning normally and rule out common conditions such as recurrent laryngeal neuropathy (roaring); which results in partial paralysis of the larynx. This condition is usually managed surgically with a tie-back and Hobday operation.
Other investigations may be required such as x-rays or ultrasound scans. For detailed investigations requiring such diagnostic equipment, we may request that your horse comes to the clinic.