Black walnut colic isn’t a real colic type—learn how gas, impaction, and exercise-induced colic differ.

Outline (skeleton)

• Hook: Colic shows up as abdominal discomfort in horses, and it often gets grouped into neat types. But one so-called “type” doesn’t actually fit.

• Quick primer: What colic means in horse health and why it matters to riders and caretakers.

• The usual suspects: Gas colic and impaction colic explained, plus a nod to exercise-related colic.

• The outlier: Black walnut colic—why it’s not a real type, but a toxin-induced problem.

• How to tell them apart: signs that point to gas vs blockage vs toxin exposure.

• What to do if you suspect colic: practical steps and when to call the vet.

• Smart habits to reduce risk: feeding, bedding, turnout, and general horse care.

• Takeaway: Understanding the differences helps you respond calmly and effectively.

What colic really means

Let me explain it plainly: colic is not a single disease. It’s a broad term for abdominal pain that can come from a bunch of different gut issues in horses. Think of it like fever in people—it’s a signal that something isn’t right inside, but the cause can range from a harmless gas bubble to a stubborn blockage or even a toxin’s surprise visit to the gut. Because horses can’t tell us precisely what hurts, we watch behavior, appetite, and gut sounds, then decide when to call the vet. That’s the practical backbone of dealing with colic.

Gas colic: the bubble party in the gut

Gas colic happens when gas builds up in the intestines. When the gut isn’t moving things along as it should, or when there’s a change in how the gut behaves after a big meal or a day of stress, bubbles can accumulate. The horse may seem restless, repeatedly looking at their flank, lying down and getting up, or pacing in circles. Some horses paw at the ground, sweat, or sweat around the neck without obvious heat from weather. It can feel dramatic, but it doesn’t always spell disaster—often, mild cases improve with rest, gentle pain relief under veterinary guidance, and adjustments to feeding and turnout.

Impaction colic: the clog in the intestinal highway

Impa ction colic is basically a blockage. Feed material, sand, or other indigestible bits can pile up and slow or stall the gut’s movement. Picture a garden hose that’s kinked; the water (or in this case, the gut’s contents) can’t flow, and pressure builds. Signs tend to be more persistent than simple gas colic: a horse might appear depressed, not want to move, and show a more pronounced looking abdomen. Reaching for the right mix of fluids, laxatives, and, if necessary, a cautious medical or surgical approach is the course that vets may chart. Prevention often centers on consistent feeding, adequate hydration, regular dental care, and a careful eye on hay quality and quantity.

Exercise-induced colic: a trigger, not a stand-alone category

Some people talk about “exercise-induced colic” as a distinct type, but let’s keep it grounded. Strenuous work, dehydration, heat, or recent changes in routine can set the stage for colic symptoms to appear. It isn’t a separate disease caused by a new gut problem so much as a stress reaction that tips the gut into discomfort. If a horse is showing colic signs during or after a workout, it’s a red flag to pause, offer water if allowed, and call the vet. The key message here is that exercise can be a catalyst for colic in susceptible animals, especially when gut motility is already a touchy subject.

Black walnut colic: not a true type, but a toxin story

Here’s the quirky but important distinction: black walnut colic isn’t a real category of colic types. The term comes up because black walnut wood shavings or bedding can release compounds that irritate a horse’s gut and sometimes trigger colic-like symptoms. It’s not a classic “type” rooted in a digestive disorder the way gas or impaction is. This is a toxin-related reaction, a reminder that what a horse eats or what they bed on matters just as much as what’s in their gut. If a barn uses black walnut shavings and a horse starts showing colic signs, the first move is to remove the source and involve a veterinarian promptly. It’s a cautionary tale about environment and management, not a new category of colic.

How to tell the difference when you’re first on the scene

You don’t need a vet appointment to notice the big cues, but you do need to know when to seek professional help. Here are the kind of signs you’ll want to watch for, across the different scenarios:

• Gas colic clues: restlessness, looking at the abdomen, pawing, milder sweating, and a gut that sounds gurgly rather than silent. The horse often remains somewhat responsive and will sometimes improve with walking and a bit of hay and water if allowed.

• Impaction clues: a dull demeanor, little interest in food, a tucked-up abdomen, and a horse that won’t move much. Pain can be more persistent, and the abdomen may feel tight or distended when palpated by a vet.

• Exercise-related cues: signs emerge in or after hard work—dehydration, rapid breathing, a noticeable shift in attitude (more tired or irritable), and then the same classic colic signals once the horse settles.

• Black walnut toxin cues: any sudden onset of GI upset after bedding changes or if shavings from black walnut were used. It’s not the same as a typical blockage; you’re watching for a broader toxic response that affects gut function and sometimes other systems.

A practical note: don’t fixate on “which type is it?” The safest move is to treat any colic suspicion as urgent. Call a veterinarian, because timing matters. If you’re ever unsure, it’s better to err on the side of caution.

What to do if you suspect colic

Colic is one of those situations where calm, quick action helps a lot. Here’s a simple, non-scarey plan you can keep in your back pocket:

• Monitor and record: Note when the signs started, what the horse has eaten, any water intake, and how the horse responds to gentle movement. A simple time-stamped log helps the veterinarian.

• Keep the horse safe: If the horse is grazing, keep them moving softly or give them a light walk, but don’t force a lot of activity if they’re clearly uncomfortable. Avoid feeding until the vet advises otherwise.

• Hydration: Offer small sips of water if allowed, or a light electrolyte solution if your vet says it’s okay. Dehydration can worsen gut motility issues.

• Prepare for the vet: Have the horse’s recent medical history handy, list of feeds and supplements, any recent changes in bedding or housing, and a description of the environmental setup (including bedding material).

• Follow professional guidance: Colic management often hinges on a vet’s assessment, sometimes diagnostic imaging, or careful medical treatment. If surgery is ever indicated, you’ll want a clear, truthful conversation about what to expect.

Smart daily habits to reduce colic risk

While you can’t predict every twist and turn, there are practical steps that help reduce the odds of colic:

• Feed consistency: Sudden changes in diet can disrupt gut rhythm. Introduce new feeds gradually and keep a steady feeding schedule.

• Hydration: Horses drink less in cool weather, so encourage water intake with palatable options and regular access to fresh water.

• Forage quality: Good quality hay or pasture fiber keeps the gut busy in a healthy way. If your hay carries dust or mold, it can irritate the gut and contribute to problems.

• Bedding choices: Avoid bedding materials linked to GI discomfort or toxin exposure—like black walnut shavings—if you know they’re a risk for your horse. Choose safe, dust-free options and keep stalls clean.

• turnout and exercise: A balanced routine that includes regular movement promotes gut motility. Sudden heavy workouts after long periods of rest can tip the gut balance.

• Dental and gut checks: Regular dental care helps ensure better chewing and digestion; colon issues often start in the mouth if chewing is painful or inefficient.

A few practical little digressions that matter

You know how a simple barn routine can make or break a horse’s day? It’s true. A lot of colic risk comes down to small choices that compound over time. If your horse is a fussy eater, adding small frequent meals can help keep gut contents moving smoothly. If you notice dust in the hay, consider soaking or choosing dust-free forage to reduce irritation. And on the environmental side, know what’s in your stalls—bedding, feed buckets, and even grooming products can influence how the gut feels after a long ride.

Another tangency worth noting: sometimes the gut’s reaction to stress shows up as colic. A big horse show, a new trailer, or a change in the herd can trigger gut motility changes. The takeaway? Consistency and predictable routines often help keep the gut on an even keel, which lowers the chances of those sudden, uncomfortable episodes.

Putting it all together: what you should carry away

• Colic is a broad term for abdominal pain in horses, with several real, recognized causes. Gas colic and impaction colic are two common types you’ll hear about a lot.

• Exercise can act as a trigger for colic symptoms, but it isn’t a separate disease on its own.

• Black walnut colic isn’t a genuine type of colic; it’s a toxin-related issue tied to certain bedding materials. It serves as a reminder that environment matters, not just what’s inside the gut.

• Quick, calm action and veterinary guidance are essential when colic signs appear. Monitor, don’t ignore, and be ready to describe what you see clearly.

• Simple daily habits—steady feeding, good hydration, safe bedding, and regular movement—go a long way toward keeping the gut happy.

A closing thought

Colic is scary because it hits at the heart of what many riders treasure most: a horse that’s healthy, willing, and ready to go. Understanding the kinds of colic, and knowing that black walnut bedding isn’t a true type, helps you respond with clarity rather than panic. When in doubt, trust the signs, honor the veterinarian’s expertise, and lean on your daily care habits. With that mindset, you’ll be better prepared to read your horse’s gut cues, and—more importantly—keep the ride smooth and enjoyable for both of you.

If you’re curious about more real-world examples or want to talk through a few hypothetical scenarios, I’m here to bounce ideas off. After all, a well-cared-for horse is a partnership—and understanding colic is part of keeping that partnership strong.