Horse Gut Sounds: What Borborygmi Tell You About Digestive Health

Put your ear against a horse's flank and you'll hear a whole world in there. Gurgles, rumbles, tinkling sounds, occasional dramatic groans from the depths of thirty meters of intestine doing its job. Most horse people know gut sounds matter. Fewer know what they're actually listening for, how to do it properly, or what the absence of sound really means.

Borborygmi. That's the clinical term for the sounds produced by gas and fluid moving through the gastrointestinal tract. It's a Greek word that basically means "rumbling," and it's one of the most useful pieces of information you can gather on a horse without any equipment fancier than a stethoscope. Or honestly, just your ear pressed flat against the barrel.

Why a Horse's Gut Is So Noisy

Horses are hindgut fermenters. Unlike cattle with their rumen doing the heavy microbial work up front, horses rely on an enormous cecum and large colon sitting in the back half of the system to break down fiber. The cecum alone holds 25-35 liters. The large colon? Around 80 liters in an average-sized horse. That's a lot of real estate dedicated to fermentation.

Fermentation produces gas. Lots of it. Methane, carbon dioxide, volatile fatty acids bubbling through liquid ingesta. The muscular walls of the intestine contract in rhythmic waves called peristalsis, pushing content along, mixing it, squeezing fluid through. Every contraction generates sound. Gas getting squeezed past a narrowing. Liquid sloshing through a bend. The ileocecal valve dumping small intestinal contents into the cecum with a rushing noise you can sometimes hear from three feet away.

The equine GI tract never stops. Horses evolved to graze 16-18 hours a day, and their digestive system reflects that. There's no off switch, no idle mode. When the gut goes quiet, something is wrong. If you'd like to see how the entire digestive system connects, we've covered that in detail.

The Four Quadrants: Where to Listen and What You'll Hear

Veterinarians divide the horse's abdomen into four quadrants for auscultation: upper left, lower left, upper right, lower right. Each quadrant sits over different portions of the GI tract, and the sounds you hear vary accordingly.

Left upper quadrant: This is over the left dorsal colon and the spleen. Press your stethoscope just behind the last rib on the left side, about halfway up the barrel. You should hear moderate, intermittent borborygmi. Rhythmic contractions, some gurgling. This area tends to produce the most consistent "normal" sounds because the left dorsal colon is actively mixing and fermenting content pretty much all the time.

Left lower quadrant: Drop down toward the flank, below the level of the point of hip. You're over the left ventral colon, pelvic flexure region, and possibly small colon. Sounds here can be more dramatic. The pelvic flexure is a common site for impactions because the colon narrows sharply as it bends back on itself. In a healthy horse, you'll hear active gurgling and fluid movement. Reduced sounds here get your attention fast.

Right upper quadrant: Behind the last rib on the right side, upper barrel. You're listening over the base of the cecum, the right dorsal colon, and duodenum. The cecum is the loudest organ in the horse's abdomen. If you've ever heard a really satisfying, deep rumble followed by a fluid rush, that's cecal activity. Some people describe it as similar to a washing machine on the rinse cycle. It should be frequent and robust.

Right lower quadrant: Lower right flank, over the body of the cecum and right ventral colon. This is another active zone. You'll hear a mix of fluid movement, gas borborygmi, and sometimes the ileocecal valve opening, which produces a distinct rushing or tinkling sound every few minutes.

A complete auscultation takes about 2-3 minutes. Listen to each quadrant for at least 30 seconds. You're grading what you hear on a rough scale: normal, increased, decreased, or absent.

What Normal Sounds Like

This is harder to describe in text than you'd think. Normal equine gut sounds have variety. You should hear something happening in each quadrant every few seconds. Not constant roaring noise, not silence, but a steady, reassuring background of activity.

Picture it like a creek. Water flowing over rocks, occasionally splashing, sometimes pooling and then rushing forward. That irregular but persistent pattern is what you're after. A healthy horse at rest will have moderate gut sounds. After a meal, they'll increase. First thing in the morning before hay, they might be slightly quieter but still present.

The key is knowing YOUR horse's baseline. Spend a few weeks listening at the same time of day, same conditions. Note what's normal. Because when something changes, you'll recognize it. One horse might always have a loud cecum. Another might run quieter overall but have particularly active lower left quadrant sounds. Both can be perfectly healthy. You're looking for deviation from their individual pattern.

When the Gut Goes Quiet

Silence is the scary one. Decreased or absent gut sounds indicate reduced or stopped peristalsis, a condition called ileus. And in a horse, ileus is an emergency until proven otherwise.

The most common cause? Impaction colic. Feed material gets packed into a section of intestine, usually at the pelvic flexure or the right dorsal colon, and blocks everything behind it. The gut responds by slowing down. Proximal to the impaction, distension builds. Distal to it, things go quiet. The horse gets uncomfortable, may paw, look at its flank, try to roll.

More dangerous: strangulating lesions. A loop of small intestine caught in an epiploic foramen entrapment, a large colon volvulus, a pedunculated lipoma wrapping around bowel. These cut off blood supply. The affected segment dies. Peristalsis stops. Gut sounds vanish in the affected region, and the horse's pain escalates rapidly. This is surgical colic, and time is everything. Hours matter. Recognizing the signs early, including that ominous quiet belly, can be the difference between a horse that survives surgery and one that doesn't. We go deeper into recognizing and responding to colic in a dedicated post.

Post-surgical ileus is another context where monitoring gut sounds becomes critical. After abdominal surgery, the intestine often goes into a temporary shutdown. Vets listen obsessively for the return of borborygmi because it signals the gut is waking back up. Hearing that first rumble after a colic surgery is one of the best sounds in equine medicine.

When the Gut Gets Too Loud

Hyperactive gut sounds aren't always a good sign either. Increased, almost frantic borborygmi often accompany spasmodic colic. The intestinal walls are contracting too forcefully, in an uncoordinated pattern, causing intermittent cramping pain. The horse is uncomfortable but usually not in the extreme distress you see with strangulation. Gut sounds are loud, frequent, and may include high-pitched, almost musical tinkling sounds from fluid being squeezed through narrow spaces.

Spasmodic colic is the most common type. It's often triggered by stress, weather changes, sudden dietary shifts, or cold water consumption after hard exercise. Many cases resolve with a single dose of flunixin meglumine (Banamine) and the passage of time. But here's the trap: some cases that start as spasmodic colic progress to something worse. A displaced colon might initially show increased gut sounds before the displacement becomes complete and sounds drop off. Always monitor the trajectory, not just the snapshot.

Diarrhea also produces hyperactive gut sounds. The colon is moving content through faster than it can absorb water, so everything rushes along at high speed. If you hear a constant waterfall of sound in the lower quadrants and the horse has loose manure, you're dealing with colitis or enteritis. Depending on the cause (Salmonella, Clostridial organisms, sand irritation, right dorsal colitis from NSAID overuse), this can range from self-limiting to life-threatening.

Sand and Gas: Special Cases

Sand accumulation in the large colon is a regional problem, particularly in sandy soil areas of the western and southern United States, Florida, parts of Australia. Horses grazing on sandy ground ingest sand particles that settle in the ventral colon. Over time, the weight of accumulated sand irritates the mucosa and can cause chronic diarrhea, weight loss, or acute sand colic.

There's a specific auscultation trick for sand. Place your stethoscope low on the ventral midline, just in front of the umbilical area. Listen for a sound like sand running through an hourglass or waves on a beach. That shifting, gritty noise suggests sand in the colon. It's not 100% sensitive, but when you hear it, it's pretty definitive. Radiographs confirm the diagnosis.

Gas colic produces its own unique soundtrack. Distended loops of intestine filled with gas create tympanic (drum-like) sounds on percussion, and auscultation reveals high-pitched pinging sounds, almost like tapping on a hollow pipe. Gas distension is painful but often resolves with walking, a nasogastric tube to relieve gastric gas, or just time. The danger is when gas distension leads to displacement because a gas-filled colon is buoyant and can flip or twist more easily than one filled with normal content.

Building Your Skills: Practical Tips

Buy a decent stethoscope. You don't need a $300 Littmann, but the $8 ones from the feed store are genuinely useless. Something in the $30-60 range with a good diaphragm will serve you well. Keep it in the barn, not in your car where it'll get too hot or too cold.

Practice on healthy horses first. Listen every day for a week. Get comfortable with the stethoscope placement, learn to block out ambient noise, and build a mental library of what normal sounds like for each horse in your care. Note the time relative to feeding because post-meal sounds are markedly louder than pre-meal sounds.

When you're concerned about a horse, listen for a full 3 minutes covering all four quadrants. Grade each one: 0 (absent), 1 (decreased), 2 (normal), 3 (increased). Write it down. When you call the vet, this information is gold. "Absent gut sounds in the right lower quadrant, decreased in the left lower, normal everywhere else" tells a vet far more than "his belly seems quiet."

Combine auscultation with other vitals. Heart rate above 44 BPM plus absent gut sounds plus pain signs equals call the vet immediately. Heart rate normal, gut sounds slightly decreased, horse seems a bit dull? Monitor closely, recheck in 30 minutes, and be ready to escalate. Check out our interactive anatomy tools if you want to really understand the spatial relationships of what you're listening to.

Frequently Asked Questions

Sources

• Merck Veterinary Manual: Colic in Horses. Available at merckvetmanual.com.
• White, N.A. (2005). Colic prevalence, risk factors, and prevention. AAEP Proceedings, 51, 122-133.
• Blikslager, A.T. et al. (2017). Equine Acute Abdomen. In: Current Therapy in Equine Medicine, 8th ed. Elsevier.
• American Association of Equine Practitioners (AAEP). Colic: Minimizing Its Incidence and Impact. aaep.org.
• Colorado State University Equine Sciences. Gastrointestinal Anatomy and Physiology of the Horse.
• Mair, T.S. & Smith, L.J. (2005). Survival and complication rates in 300 horses undergoing surgical treatment of colic. Equine Veterinary Journal, 37(4), 296-302.