Unlike choking in people, which can lead to suffocation within minutes, choke in horses is more of a slow-motion disaster. A blockage of the esophagus rather than the airway, choke occurs when a horse tries to ingest inadequately chewed feed, a large chunk of carrot or something else he cannot swallow properly.
Choke does not inhibit a horse’s breathing but it can be so unpleasant that he becomes anxious or panicky, and if the blockage persists the resulting esophageal damage may seriously compromise his health in the long run.
Fortunately, most episodes of choke clear on their own. Even as he strains to relieve the blockage by stretching out his neck and coughing, a horse continues to produce saliva, which lubricates the esophagus and may eventually enable the mass to pass to the stomach. It’s a good idea to call a veterinarian anyway. A full examination can reveal potential physical causes, such as a growth or swelling in the neck or dental abnormalities, and an endoscopy may be needed to detect any injury to the esophagus. Your veterinarian may also help you identify management changes that can reduce the risk of future episodes.
If the blockage remains, the veterinarian can do several things to address the problem. After performing an examination on the horse to determine the exact location and size of the blockage, the veterinarian is likely to administer a sedative, both to relax the horse and to encourage him to lower his head and ease the muscles that are constricting the bolus. This alone is often enough to take care of the problem. If it doesn’t, the next step may be to insert a nasogastric tube and patiently flush the mass with warm water, a process that sometimes requires many gallons. The veterinarian may siphon the water back off in hopes of drawing some of the chewed feed out with it, repeating until the remaining mass is small enough to pass. In addition, the hormone oxytocin, which encourages smooth muscle relaxation, or the colic medication Buscopan, which can relax a portion of the esophagus, may be administered.
If these efforts fail, the horse may need to go to the hospital to undergo a procedure under general anesthesia. The blockage may be freed using an endoscopic tool inserted down the esophagus. In rare cases, surgery may be required to remove the mass.
Very few cases of choke require endoscopy or surgery. Still, even a mild case is not something to take lightly. You’ll need to continue to monitor your horse for days afterward for signs of cough, fever or a runny nose---if your horse had drawn even a little foreign material into his airways during the episode, he is at risk for life-threatening aspiration pneumonia. Choke can also be a sign of an injury to the neck or an underlying health issue that requires attention. At the very least, you may need to consider management changes to minimize the chances that it will happen again.
Managing to prevent choke
Any horse may choke in an awkward moment while eating. But the problem is more likely to occur in horses who have difficulty chewing or who might be inclined to bolt their food. Limiting your horse’s risk of choke means addressing all of these possibilities:
• Schedule regular veterinary visits, including dental work. Malocclusions and other dental abnormalities make it difficult for horses to chew their forage adequately, and they may swallow larger boluses of drier material. In routine examinations, your veterinarian can identify and fix developing problems before they become serious. He can also perform a more comprehensive examination that may uncover other problems, such as injuries or neurological abnormalities, that may affect a horse’s ability to chew and swallow efficiently.
The need for dental care is well established in older horses who have worn their molars down, but young horses can have issues as well, in- cluding caps or “baby teeth” that don’t shed properly. Younger horses may also be more inclined to pick up and chew on foreign objects that can damage their teeth.
Annual exams are adequate for healthy adult horses who have never had serious dental issues, but six-month intervals may be more appropriate for older horses or those who’ve had troubles in the past.
• Provide forage that’s easy to chew. Horses who routinely eat coarser hay are more likely to choke. If your horse is having difficulty eating his hay, you may find larger unchewed bits in his manure. You may also find quids--- cigar-shaped wads of partially chewed hay. Check with your veterinarian to see if any dental abnormalities can be addressed. At that point, you might consider switching him to a complete feed or another type of forage that he can eat more readily. Soaking or spraying water on hay can also soften it up and make it easier to chew. It may be necessary to soak pellets and other feeds for horses who have a particularly hard time chewing dry food.
• Slow down speedy eaters. If your horse gobbles down his food, he may not always be taking the time he needs to chew properly. A number of strategies may help. To simply slow him down, a slow feeder for forage has small openings that limit the amount of hay a horse can pull out in one bite, so he can’t swallow large mouthfuls at once. You can also find slow feeders that are designed for pellets and other feeds, to limit the amount a horse can pick up in one mouthful. Other ways to accomplish that goal include placing large stones in the feed bucket or spreading the ration out in a shallow pan.
Also consider why the horse might be inclined to eat too fast. A horse who gets only one or two large meals per day might get so hungry between feedings that he tears through his food once it arrives; breaking up his rations into multiple smaller meals might slow him down.
A horse who is fearful or stressed may be more inclined to wolf down his feed as quickly as he can. If your horse gets nervous at mealtimes, try to keep his feeding routine as consistent as possible, and introduce any changes gradually. Also, avoid feeding concentrates while the horse is riding in a trailer. The stresses and distractions of the road trip may prevent him from taking the time to chew properly.
Herd dynamics may also affect mealtime stresses. If a bully in your herd is intimidating a more timid horse, you may need to separate them at feeding time. The more timid horse may do better in a quiet stall or corral where he can eat in peace.
• Allow full recovery after sedation. Sedative drugs relax the muscles, which may limit a horse’s ability to swallow effectively. If your veterinarian administers a sedative during an examination or procedure, be sure to ask how long you need to wait before allowing the horse to eat or drink again. Generally, it takes a horse about an hour to fully recover from sedation.
• Provide ample water. Free access to fresh, clean water is important to your horse’s health for many reasons, including reducing the risk of choke. In the wintertime, you’ll need to be diligent about keeping your horse’s water free of ice.
• Break up treats. A horse’s esophagus dilates to only about two inches in diameter. If he tries to swallow anything larger, the object will likely get stuck. Break down hard treats, such as apples and carrots, into pieces no larger than your thumb. After offering a treat, stick with your horse to make sure he chews and swallows it.
• Feed low. Use a ground feeder for grain and find ways to offer hay that encourage a horse to lower his head when he eats.
Even a single case of choke can damage a horse’s esophagus ---by loosening the muscles to create a flaccid area (diverticulum), for example, or by scarring the lining that narrows the passageway---and that can leave him more vulnerable to future episodes. But with careful management, chances are good that your horse will be able to live a long and healthy life with no further episodes of choke.
This article was originally published in EQUUS 485, February 2018