Image used with permission by the American Association of Equine Practitioners.
The term “choke” in horses refers to an obstruction of the esophagus, a soft muscular tube that leads to the stomach. It is a common misconception that “choking” horses have a blockage of their airway (trachea) and cannot breathe.
What are the signs a horse is choking?
The most common sign of choke in the horse is a green, often frothy discharge from one or both nostrils. The discharge usually contains feed material and saliva buildup. Choking horses frequently stretch their necks and cough or tense their neck with a gagging motion.
What should I do if I think my horse has choked?
The most important thing to remember is not to panic. Many choke cases resolve spontaneously, and true choke does not cause horses to asphyxiate (aka suffocate). The next step is to contact a veterinarian, especially if the episode has lasted more than 30 minutes. Remove access to food and move the horse to a smaller stall or pen, if possible, for close monitoring.
How is choke in horses treated?
After performing a physical exam, your veterinarian will likely administer sedatives. Sedation serves multiple purposes, including reducing anxiety; lowering the head to reduce the risk of inhalation “aspiration” of food and saliva; and relaxing the esophagus. During the visit, the horse might receive other medications, including an antispasmodic drug (to help relax the esophagus) and anti-inflammatories. A nasogastric tube is typically passed through the nose and into the esophagus, allowing your veterinarian to assess if the blockage is in the esophagus and try to clear the obstruction. Your veterinarian may also give the horse electrolytes through the tube to help with rehydration. Most choke episodes resolve with on-farm treatment, but sometimes further in-hospital investigation and treatment are necessary. An endoscope, a long camera, is sometimes required to visualize what is causing the obstruction and assess for esophageal damage/dysfunction.
What causes horses to choke?
The most common causes include improperly prepared feed (such as dry feeds not soaked properly) and dental disease. Older horses are especially at risk because they are prone to having dental abnormalities. Therefore, a veterinarian should evaluate your horse’s teeth during routine visits. Although not as common, horses can also choke after eating treats such as carrots and apples too readily and without chewing them properly.
Can horses suffer choke-related complications ?
The main complication of choke is aspiration pneumonia, which can occur when saliva and food material are inhaled down the trachea and into the lungs. Even small amounts aspirated into the lungs can create an infection and develop into severe pneumonia. Signs of aspiration pneumonia are typically seen a few days to a week after the choke incident. It is critical to monitor your horse for continued coughing, inappetence, and fever (a temperature over 101.5-degrees Fahrenheit) daily for around a week after the episode. Antibiotics may or may not be prescribed at the time of the choke and are veterinarian and case-dependent. Esophageal injuries, such as ulcers or bruising, can also be seen. Another complication of choke is the formation of an esophageal stricture. A stricture is essentially a narrowing of the esophagus due to scar tissue formation when the obstruction causes injury to the tissue of the esophagus. These can be difficult to treat and can cause repeated choke episodes. About 37% of horses will re-obstruct 24-48 hours after a choke, so veterinarians typically recommend withholding feed for about 12 hours. Colic before or after a choke episode is also possible.
How can I keep a horse from choking?
Routine physical exams that include an oral exam or dental float are essential. Poor dentition can cause improper chewing and swallowing of larger pieces of feed material. Senior horses, horses with a choke history, or horses with known dentistry issues are typically placed on a mash or no-hay diet. Mashes should have a “soup-like” consistency. Undersoaking these feeds can increase horses’ choke risk; therefore, feeding mashes at a watery consistency is important. Your veterinarian may also recommend a grazing muzzle to decrease the horse’s grazing rate and course feed material intake. Some horses with recurrent choke episodes may require mash-only diets with no coarse hays.