If you’ve ever seen equine choke, you know how traumatic it can be for horses, and how helpless it can make those caring for them feel – especially if veterinary intervention is required. The best thing you can do to prepare yourself and protect your horse in any emergency is familiarize yourself with the facts before you’re in a critical situation.
Large animal vet and horse owner Dr. Amy Gaw of Temiskaming Veterinary Services in New Liskeard, ON Canada walks us through how to prevent choke, what to do if you suspect your horse may be choking, and how to care for him or her afterwards.
Why Does Choke Happen?
It’s important to remember, says Dr. Gaw, that choke in horses is not immediately life-threatening, although if left untreated it can result in dehydration, severe damage to the esophagus, and aspiration pneumonia. In people, choking results from an obstruction in the trachea (windpipe) that cuts off the intake of air to the lungs, whereas in horses it’s caused by an esophageal obstruction in the muscular tube through which food passes to the stomach. Horses have both a trachea and an esophagus, so they’re typically still able to breathe while suffering from choke, although they may have increased difficulty due to stress.
Obstructions can occur at any point along the esophagus, from where it begins at the back of the throat all the way down to where it connects to the stomach. However, there are common junctures at which choke typically occurs. Dr. Gaw says two points prone to obstruction are the thoracic inlet at the base of the neck, which is narrower than the rest of the esophagus, and the diaphragm just before entry into the stomach.
Choke can happen at any time to any horse, but the potential increases based on several factors including, age, grain consumption, throat health, and eating habits.
“Choke happens when horses eat something they shouldn’t have, or when a foreign body becomes lodged in the esophagus,” says Dr. Gaw. “It can also occur when horses eat too fast and food bunches up in the esophagus.”
Common culprits include hay cubes that aren’t soaked well enough, chunks of apple, chunks of carrot, or other foods that aren’t processed well enough before feeding.“It can also be caused by things like beet pulp, which needs to well-soaked before feeding,” Dr. Gaw says. “When beet pulp meets water it expands, and what might look like only a handful is really much more.”
Unsoaked beet pulp makes for some of the worst cases of choke because when it comes into contact with the saliva inside the esophagus and becomes partially soaked, it becomes like concrete.
Sometimes choke can occur with foods that are typically safe for horses because the musculature that controls the esophagus becomes weaker with age, or because the mechanics of the jaw itself are hindered by bad teeth. “Sometimes when they haven’t had the routine dental care they’re supposed to have, some horses get really sharp, pointy bits in their mouths where they avoid chewing because it hurts, so they end up swallowing bigger hunks of food,” Dr. Gaw says. “I see it more often in older horses, but it can also happen in younger horses with dental issues.”
For more information on senior dentistry and feeding, see this Equine Guelph horse care info sheet.
Choke can also happen when horses have a damaged throat due to consumption of things like unwetted powdered electrolytes, and from dehydration before eating or inadequate access to water.
How to Identify Choke
Dr. Gaw warns that signs of choke vary from case to case and can be both obvious and subtle. In obvious choke, horses are visibly distressed, and often have mucous and brownish or greenish saliva discharging from the nostrils. The horse may be standing with a lowered head and outstretched neck, coughing, making wheezing noises, or making indications of struggling or panicking while trying to swallow. In some cases, you can see the obstruction protruding in a lump on the left side of the neck, where the esophagus is located.
In subtle cases of choke, horses may only seem uncharacteristically lethargic, refuse food, or exhibit other atypical behaviours such as pawing the ground for no apparent reason, or they may simply seem “not right.”
Dr. Gaw recalls one case of subtle choke where she was called to help a horse that had recently returned from a show two hours away from home. Because the horse wasn’t eating and seemed agitated, the owners thought he was suffering from colic. When she sedated the horse, food and mucous discharged from his nose, and she immediately recognized the problem was choke.
When to Call the Vet
Choking is common and often resolves itself on its own. If you think your horse is choking, monitor them closely for up to fifteen minutes to see if they can clear the obstruction without help. “Eight times out ten when somebody calls me about a choke, it’s resolved by the time I get there,” says Dr. Gaw. “It’s scary to see, but a good chunk of the time the horse deals with it on their own.”
If the horse hasn’t dislodged the obstruction after fifteen minutes, the vet should be called, especially in more remote rural areas where it may take vets longer to answer emergency calls. Dr. Gaw says she would rather get the call and arrive to find the horse has returned to normal, than have someone wait to call, hoping the horse will pass the obstruction on his or her own.
Similarly, if non-critical cases of choke happen to your horse more than once in a short period, it’s important to call the vet out for a checkup. Horses can suffer from unseen causes of choke, such as throat ulcers or cysts.
What to do While Waiting
Sometimes, massaging the neck can help loosen the obstruction. You might be able to easily locate the obstruction because you can see it from outside. First find the trachea, the large rigid tube at the front of the neck that extends down from the throatlatch. “Just to the left-hand side, there’s a groove in their neck,” says Dr. Gaw. This groove contains the esophagus. “If you massage downwards in that groove you can sometimes help massage the food bolus down.”
Never attempt flushing out the obstruction with water or mineral oil. “If you put something down the throat you’re expecting them to swallow, and they can’t move the obstruction, they’re not going to be able to move the mineral oil or water, and there’s the risk that the liquid could then go down into their lungs.”
Although it’s hard to feel as though you’re doing nothing, the best thing you can do, says Dr. Gaw, is to keep your horse calm. Keeping yourself calm is the second best thing. Dr. Gaw recommends walking your horse, if he or she is willing and able. An added bonus is that your horse’s muscles may relax and the obstruction may loosen.
If your horse remains in its stall, remove all grain, hay and water.
Treatment
The most common treatment for an advanced case of choke is lavage through a nasogastric tube. This can be a harrowing thing to watch if you’ve never seen it before. Horses are first sedated, and are often given a muscle relaxant to allow the obstruction to pass more freely. Then the nasogastric tube is inserted via a nostril, rather than the mouth. Passing a tube through the nose allows vets to manoeuvre the tube past the barrier of the soft palate.
“If you pass the tube through the back of the mouth, because of the soft palate, you’re almost guaranteed to get it to the trachea,” explains Dr. Gaw.
“We advance the tube until we get resistance, and then we pump water in slowly to dissolve the obstruction and make it easier to pass.” Warm water is poured via an elevated funnel into the tube. “As water goes in, water with food or the obstruction will come back up the tube. “Then we do it again, advance flush, advance flush, until we hit stomach.”
This process, called a lavage, is repeated until the obstruction is cleared. Clearing an obstruction can be difficult even for experienced vets and involves a lot of guesswork, time, and patience.
Once the tube has reached all the way to the stomach, the blockage has been cleared. Vets know when they hit the stomach because the stomach has a distinct (and unpleasant) smell. “We’re also going by the length of the tube,” says Dr. Gaw.
Once the danger has passed, your vet may give your horse water with added electrolytes before the tube is removed, to prevent dehydration.
After the tube has been removed, your vet may pre-emptively administer antibiotics to prevent aspiration pneumonia, a common complication from choke that occurs when solid foreign matter is inhaled into the lungs. Vets might also prescribe NSAIDs for pain relief.
Aftercare
Depending on the severity of the choke, horses may take days or weeks to recover. The esophagus can be damaged by the obstruction, and if the horse has had a nasogastric tube inserted into the throat, there may be internal scratches or scrapes.
Dr. Gaw also warns that, even after your vet has cleared the obstruction, if a horse’s abnormal behaviour persists after a day or two, there may still be a partial obstruction somewhere in the esophagus and the vet may need to be called out again.
For the best aftercare suited to your particular horse’s needs, including how old your horse is, what his activity levels are, and what his teeth are like, Dr. Gaw advises taking detailed notes from your vet.
Some horses are able to eat regularly after the sedation wears off, but others are more reluctant. Depending on the situation and what the horse choked on, your vet may recommend keeping your horse off grain for a few days or longer. Your vet also may recommend soaking hay, or using a hay bag to prevent horses from eating hay too quickly with a sore throat. If the obstruction occurred in the throatlatch area, your vet may recommend switching from a wall feeder to a round tub located on the ground.
If you have a senior horse who has trouble chewing regular long-stemmed hay, hay cubes may be an alternative going forward or while recovering – but it’s very important to soak them properly, as hay cubes can cause choke. “I say soak hay cubes until you think you’ve soaked them enough, and then soak them more,” Dr. Gaw says.
Grain may need to be reintroduced into the diet slowly, and how you feed grain may need to change going forward. “You can sometimes start them back on bran mashes and gradually add in the regular feed, but if it was a soaked feed they choked on to begin with, I would feed smaller amounts more often so they’re not getting a big glut of food at once.”
It’s also important for your horse to have a dental exam to see if there are any underlying problems with the teeth, especially if your horse’s last dental visit was over a year ago.
If your horse choked because he’s prone to gobbling or “bolting” his food, a hay net may be useful, and there are also slow grain feeders on the market, similar to those used for dogs. An alternative is simply finding a large rock or two and putting them in your horse’s feed bucket so he or she has to eat around them or use his or her nose to move them, thereby slowing down. Be sure the rock is large enough that your horse can’t accidentally eat it!
Lastly, don’t forget Dr. Gaw’s number-one tip for being prepared for any horse emergency: clear, simple driving directions to your barn posted on your tack room, barn aisle, or feed room wall.