Oesophagus
The equine esophagus is a muscular tube approximately 125-150 cm long that transports food from the pharynx to the stomach via coordinated peristaltic waves. It runs along the left side of the trachea in the neck (hence palpable in the left jugular groove), passes through the thorax dorsal to the trachea, and enters the stomach through the cardia at a sharp angle. This oblique entry, combined with the strong cardiac sphincter, prevents vomiting; a unique equine characteristic with significant clinical implications, as gastric rupture can occur before retrograde passage of contents.
The equine esophagus is approximately 125-150 cm long and runs along the left side of the neck (left jugular groove). The upper third has striated muscle, the lower third has smooth muscle, and the middle third is mixed. Horses CANNOT vomit due to the powerful cardiac sphincter and the acute angle at which the esophagus enters the stomach. Endoscopy is the gold standard for evaluating esophageal disorders.
Blockage of the esophagus by a food bolus (commonly dry pelleted feed, beet pulp, or apple/carrot pieces). The most common esophageal emergency in horses. Unlike choking in humans, the airway is not o
Narrowing of the esophageal lumen due to fibrosis, usually secondary to previous choke, esophageal surgery, or chronic inflammation.
Full-thickness tear of the esophageal wall, usually iatrogenic (from nasogastric tube passage) or secondary to severe/prolonged choke.
Diffuse or segmental dilation of the esophagus with loss of motility. May be congenital or acquired (secondary to autonomic dysfunction, grass sickness).
Blockage of the esophagus by a food bolus (commonly dry pelleted feed, beet pulp, or apple/carrot pieces). The most common esophageal emergency in horses. Unlike choking in humans, the airway is not occluded. Signs include: Bilateral frothy nasal discharge (often green/feed-colored); repeated swallowing attempts; arched neck; coughing; anxious behavior; palpable firm mass in left jugular groove
Narrowing of the esophageal lumen due to fibrosis, usually secondary to previous choke, esophageal surgery, or chronic inflammation. Signs include: Recurrent choke episodes; difficulty swallowing; salivation; weight loss; may require dietary modification (soaked feeds)
Full-thickness tear of the esophageal wall, usually iatrogenic (from nasogastric tube passage) or secondary to severe/prolonged choke. Signs include: Subcutaneous emphysema in cervical region; fever; cellulitis; septic pleuritis if thoracic portion; crepitus on palpation; often fatal if not recognized quickly
Diffuse or segmental dilation of the esophagus with loss of motility. May be congenital or acquired (secondary to autonomic dysfunction, grass sickness). Signs include: Chronic dysphagia; nasal return of food and water; weight loss; recurrent aspiration pneumonia; distended esophagus visible on radiography with contrast
The equine esophagus is approximately 125-150 cm long and runs along the left side of the neck (left jugular groove). The upper third has striated muscle, the lower third has smooth muscle, and the middle third is mixed. Horses CANNOT vomit due to the powerful cardiac sphincter and the acute angle at which the esophagus enters the stomach. Endoscopy is the gold standard for evaluating esophageal disorders.
See the Esophagus on our interactive 3D horse model. Open 3D Model