In the horse "choke" refers to obstruction of the esophagus (food tube). This obstruction is almost always due to some sort of feed material (hay or grain) blocking the esophagus so that the horse is unable to swallow. Clinical signs of a horse that is choking include gagging, retching, coughing, apprehension and food tinged mucous/saliva draining out of the mouth and nose. The amount of this discharge varies from small amounts to large volumes of material pouring out of the mouth and nose, If the horse attempts to eat the feed will drop out of the mouth. If put in a dark, calm,  quiet stall, all food and water removed and the horse is left alone for an hour or so many cases of choke (up to about 50% in our practice) will resolve themselves. Attempts to relieve the choke by massaging the neck is discouraged as this is rarely effective and may agitate the horse and worsen the conditon.

If the signs persist after leaving the horse alone as above then veterinary attention is required. After an initial assessment to confirm the diagnosis of choke the horse is first tranquilized. A nasogastric (stomach tube) is then passed up the nose, through the pharynx and into the esophagus up to the site of the obstruction. Gentle pressure applied to the tube will sometimes push the obstruction down into the stomach. More commonly though it is necessary to flush water through the tube to both break down the obstruction as well as dilate or distend the esophagus around it.Manipulation of the tube while flushing will almost always allow for resolution of the choke as the tube is finally able to enter the stomach. Once inside the stomach the water being pumped will no longer be seen coming out the mouth and nose. Adequate tranquilization is necessary to keep the horse's head down to help prevent aspiration pneumonia. The horse will generally receive antibiotics and antiinflammatories for several days following resolution of the choke and return to normal feeding is done gradually. If it is not possible to relieve the obstruction using tube lavage then the horse may need to be sent to a referrall practice for possible surgery (this is extremely rare). Some veterinarians may use the drug oxytocin in refractory cases althought the use of this drug has not been proven to be an effective treatment for choke.

Contributing causes of choke may include eating too quickly (horses that dive into their feed agressively my benefit from having several fist sized stones put in the feed tub to slow them down), poor teeth or inherent esophageal pathology.

Food-tinged nasal discharge in a horse with choke.

Choke should considered an emergency and communication with the veterinarian early in the course of the problem is essential. 

WHAT TO DO IF YOU NOTICE THE ABOVE SIGNS:

1.  TAKE AWAY ALL FOOD AND WATER IN STALL.

2.  CALL THE VET TO DISCUSS THE SITUATION.

3.  LEAVE THE HORSE ALONE AND QUIET TO POSSIBLY RELAX AND RESOLVE THE CHOKE HIMSELF (often for an hour or so)

4.  DO NOT MASSAGE THE HORSE'S NECK OR GET HIM AGITATED.