Key Points
- When it comes to colic in horses, or abdominal pain, it’s not a question of if but when (and how severe).
- Colic impacts all walks of horses everywhere. In our experience, the causes of colic in horses vary by region.
- Stress, diet, dehydration, and weather changes can put horses at risk for colic.
- Ideally, we prevent colic in the first place by preparing for and anticipating shifts in the equine microbiome.
Colic, or abdominal pain, doesn’t discriminate; horses of all breeds and disciplines suffer and even die from the condition. What causes colic and how it manifests could differ significantly depending on where you live, so it’s important to understand the various types, including sand colic, gas colic, and impaction colic.
“Colic is always in the back of a horse owner’s mind, and I think in large part it’s not a question of ‘if’ but when and how severe the colic will be,” says Dr. Keith Latson, an equine surgeon and co-founder and director of operations at FullBucket, a veterinary-strength supplement business based in Weatherford, Texas. “And the hope is always that it’s some mild form of colic.
“Colic in horses can come from any number of things,” he adds. “It can come from a partial or complete intestinal blockage from food, sand, or a ‘rock,’ called an enterolith, that actually builds and develops in the intestines.”
Latson and Dr. Rob Franklin, an equine internal medicine specialist and co-founder of FullBucket, who have practiced in regions across the U.S. and even abroad, recently discussed clinical signs of colic horses they’ve treated in each of these areas.
California: ‘Pearls’ and Sand
If a horse in California starts showing signs of abdominal pain—anything from looking and biting at the sides repeatedly to stretching out to urinate but not peeing—Latson first thinks about mineral or sand buildup.
“If they’re on alfalfa or they’re in a sand lot and potentially ingesting sand, I’ll have a higher index of suspicion that they may have an intestinal blockage or irritation that is related to an enterolith or a mineral accumulation” around a foreign body in the gut–kind of like how a kidney stone forms, or a pearl in an oyster.
“Enteroliths are relatively common and, in fact, the majority of the surgeries that I did in colicky horses in California were horses that had developed enteroliths, and often multiple enteroliths,” he says. “So, they could be small and triangular, or they could be large and look like an ostrich egg, depending on where they developed in the intestines.”
Franklin has also seen enteroliths while practicing in California, Florida, and now Texas, but “about every other horse that we performed colic surgery on (in California) was due to an enterolith.”
Alfalfa’s mineral content—protein, phosphorus, and magnesium, particularly—causes these stones to form. “We would always ask as part of our patient history, ‘Where do you get your alfalfa?’” he says “‘Are you getting it from California, Nevada?’ If owners were getting their hay brought in from Colorado or Montana (where soil content of these minerals tends to be less), we had a much lower suspicion for those sorts of things. And then we might start thinking about sand accumulation in the gut.”
California horses eating off the ground in paddocks or enclosures or ingesting grass in sandy areas inadvertently consume sand. “Some of them are not very careful eaters, and some of them are just straight up dirt eaters,” says Franklin. Horses in Florida, Texas, and the Mountain West out to the desert consume sand, too. The sand causes obstructions, irritates the intestinal lining, alters gut motility, and causes overt colic, often gas colic because of obstruction.
Prevention: As for mineral buildup, Franklin doesn’t want West Coast residents who feed alfalfa to be preoccupied with this issue. “Alfalfa is great forage for horses, of course, but there are some best practices to reduce the incidence of colic, including enterolithiasis.
“Keep lots of fluids, extra fluids, and a wet feed in front of your horse,” says Franklin. “Maybe it will help carry out some of that particulate matter like sand, and maybe if you add psyllium—which binds to the sand in sort of a jellylike way—to it, that will help, as well. In California most people just offer it as a normal part of their feed regimen.”
Typically, the psyllium regimen is one week on, three weeks off. “If you feed it consistently the horse will start to develop some microbes that will break that psyllium down,” says Franklin, “instead of it acting like a gel that will carry some sand out.” Other anti-colic management approaches include feeding on rubber mats surrounded by railroad ties (to keep the sand out), rather than throwing hay out on sandy ground.
Rocky Mountains: Weather-Related Dehydration
Latson also practiced in Bozeman, Montana: “There were a lot of ranch horses, as well as a lot of high-level hunters and jumpers. The way those horses were managed was very different, but the commonality between disciplines was impending weather changes oftentimes affected the amount that a horse would drink.”
In other words, with snowstorms came a spate of colics. Whether waterers, buckets, or troughs froze or horses simply didn’t want to drink, veterinarians saw a spike in dehydration cases and resulting colic. “I think that was the most dangerous thing in the winter, you had a trough heater that malfunctioned, and now you’ve got horses that haven’t had access to water for three or four days,” says Latson. “Horses need that water to hydrate the gut, to hydrate the feed, to hydrate their bodies before things start shutting down, like the motility of the intestine.”
“Yes,” Franklin adds, “when they start to get dehydrated, the first place they pull reserves from is that digestive tract. It holds tens of gallons of watery contents, so it’s a great life-sustaining reservoir for the dehydrated patient, but you rob Peter to pay Paul,” resulting in colic and eventual kidney shutdown.
Prevention: Horse owners can help thwart these types of cases by keeping their waterers, troughs, and heaters clean and serviced and by having a backup water provision plan for when equipment breaks or malfunctions.
East Coast: Show Circuit Travel
Back in the warmer climes the East Coast show circuit tends to follow, there’s yet another set of horse colic risks.
“Those are horses who are spending a lot of time on trailers, they’re spending a lot of time in new barns, and, by and large, they’re experienced at that, and so are their owners,” says Latson. “But I think as we’re traveling with horses, we also know that there is a lot of stress and a microbiome shift associated with it.”
The equine gut microbiome is the ecosystem of microorganisms—bacteria, protozoa, fungi, and viruses—therein, living in harmony with one another. Dehydration; stress from travel, diet changes, and competition; and low-grade infection can throw off the balance, with some of the horse’s gut residents overtaking the good microbes and wreaking havoc.
“When we get those horses that are just not feeling quite right, whether it’s because of that low-grade exposure or because of the stress, there’s a microbiome shift, there is less intake of water while they’re traveling, and potentially less intake of water once they get into their barns,” says Latson. “So, those are horses that I get concerned about impaction colic, particularly as they dive into that feed once they get into the barn after traveling and after not having enough water. Those are the ones that you get the call at about 2 a.m., ‘Hey, I just checked on my horse, we trailered in this morning and, man, she’s just uncomfortable, she’s kicking at her belly,’ and my brain immediately goes, ‘Ding, ding, ding, impaction!’ and the hope is that it’s a nonobstructive or only a partial impaction and not one that has started to solidify.’
Prevention: You can prevent impaction colic by keeping horses hydrated—helping them acclimate to water sources on the road by getting them used to some kind of flavoring (whether an electrolyte powder or a fruit juice or Gatorade before a trip)—and getting ahead of stress-related horse microbiome shifts with FullBucket’s Equine Probiotic Paste.
Gulf Coast States: Hay Batch Transition
Finally, “as you drive around Texas and Georgia and Florida, all these Gulf Coast states, there are thousands upon thousands of horses eating round bales, and they do it without a problem,” says Franklin. “But we start to see problems when we get new batches of coastal (Bermudagrass) hay, typically round bales.”
He explains that this hay isn’t necessarily bad but, rather, if the hay is coarser than the former batch horses were consuming, it can end up wadding up and causing intestinal impaction.
Prevention: “For the horses that are chronic colickers, I just insist that they come off those round bales,” he adds. “I’ll typically add some alfalfa hay in there, as well. I think it is not only nutritious but also prevents some of that coastal hay from matting up and causing those big impactions. I think for every alfalfa impaction we probably see 100, if not more, coastal hay impactions.”
Take-Home Message
Colic can happen to any horse anywhere, but certain colic types tend to show up in some regions more than others. Be alert for signs of gastrointestinal distress and pain and call your veterinarian immediately at signs of colic.
Make hydration, diet, stress management, and gradual hay batch transitions a priority when managing your horses and talk to your veterinarian about incorporating an equine probiotic and prebiotic product to help keep your horse’s microbiome in a steady, happy state.
