Our practice has treated a number of “chokes” recently, and after answering similar questions multiple times we thought a few notes about that condition in horses might be appreciated. Choke – when discussing it in regards to a horse- is a blockage in the esophagus. Usually, the blockage is caused by feed material. Long stemmed grass, course hay, grain eaten too quickly and bad dentition are all common culprits. When the food material blocks the horse’s throat, saliva and mucous back up into the oral cavity and the nose and then run out. Food material coming from the nostrils is an obvious sign. Often the horse coughs violently and slings his head around as he tries to breathe past the accumulated food/mucous/saliva in his throat. Many horses, understandably, are distressed and anxious and seem to be in great pain. Pain can certainly be real, as part of the reason for the blockage is that the esophagus constricts around the blockage and that can be uncomfortable.
While a choking horse often seems to be in great distress – and he probably thinks he is – most of the time they relax and hang their head and drainage from the nostrils makes breathing easier. As the horse calms down and the esophagus loosens and continues its work of swallowing, aided by lubricating mucous and saliva, the obstruction loosens and passes on its own. Many episodes of choke resolve without treatment – just time to relax. No more drainage from the nostrils is a good indication that the choke has resolved but do not offer food until you have seen the horse drink and swallow normally.
The relaxation process can be aided with sedation. Many barns keep oral sedation gel on hand for just such an event, especially if there are horses with a history of choke on the premises. The oral sedation is designed to be absorbed through the mucous membranes of the mouth, so swallowing difficulties are not a problem. When time and relaxation are not enough to help clear the choke then further treatment may be needed. This often involves passing a naso-gastric tube (through the nose, into the esophagus/stomach) to flush the obstruction. Sometimes the tube itself will dislodge the feed material but usually we need to pump water into the esophagus to break up the obstruction. Often this means flushing water in and out of the horse’s nose and throat.
If an episode of choke does not resolve quickly and simply further considerations for treatment include antibiotics and anti-inflammatories. The fluid and feed materials that back up in the esophagus obstruct the airways and can be aspirated into the lungs, and this can lead to respiratory infections. The feed material packed into a constricting esophagus can cause ulcerations and injury to the throat, even swelling and chronic stricture, or narrowing. Anti-inflammatories can minimize this damage but feeding wet and soft feed for some time after the event can also help with healing and prevent further damage.
Many chokes are one time problems, a single event – but horses can be repeat offenders for a couple of reasons. Poor dentition, as mentioned above, is a common contributing problem. Poorly aligned teeth, missing teeth, or even oral pain can lead to insufficient chewing and that may interfere with swallowing. Keeping your horse’s teeth well maintained can help prevent problems. Some horses simply do not have enough teeth to adequately chew normal feedstuffs. In those cases, diet may need to be adjusted to help. This could include wetting and softening hay, or even chopping the hay. Sometimes a complete feed will need to replace forage. These are often pelleted and the pellets can be a choking hazard in horses that do not chew properly as they swell in the throat. Make sure to wet the pellets as needed. Even horses with good teeth can choke repeatedly from bad habits like eating too fast or too aggressively. Some horses need to be fed separately to ease herd stress. Others may need help to eat more slowly. This can be done by adding a large rock (bigger than he can swallow) to the feeder, or feeding out of a larger pan, even a muck tub, to prevent large mouthfuls.
To sum this up, tell your horses to chew slowly and completely. Take care of their teeth. Feed appropriate materials. If they choke, don’t be stressed and anxious, and tell your horse to relax too. Let us know what you are seeing and we will help as needed.