Understanding Colic in Horses

Colic is a term used to describe abdominal pain in horses. While the majority of cases arise from the gastrointestinal tract, other body systems can rarely cause similar signs. Recognising the signs and contacting your vet early is critical to a favourable outcome.

Horses communicate through their behaviour. Even small changes may indicate discomfort. Common signs include pawing at the ground, flank watching, kicking, or biting at the belly, repeatedly lying down, rolling excessively, dullness, depression, inappetence, sweating without exertion, and stretching as if to urinate.

Spasmodic or Idiopathic

This is the most common form. Spasmodic colic results from abnormal intestinal contractions, causing painful spasms. Idiopathic colic refers to cases where the exact cause cannot be determined, despite thorough investigation. Most of these cases respond well to conservative medical treatment.

Impactions

Impaction colic happens when ingesta (feed material) becomes dehydrated and forms a firm mass that blocks normal passage through the gastrointestinal tract. These obstructions most often occur at anatomical bottlenecks where the gut naturally narrows or changes direction, for example, at the pelvic flexure. Caecal and small intestinal impactions are less common but often more serious. Several factors increase the risk of impaction, including inadequate water intake, abrupt dietary changes, parasite burdens, poor dental health, recent management changes, and conditions that decrease gut motility. Whilst the majority of impactions can be treated with hypertonic fluid solutions administered via a nasogastric tube, severe cases may require surgery.

Displacements, Strangulations, and Torsions

These are less common but potentially life-threatening conditions. A displacement occurs when one segment of the intestine moves out of its normal position within the abdominal cavity and becomes trapped. This can interrupt intestinal motility and may lead to obstruction, but blood flow is usually preserved unless there is strangulation. Strangulation describes situations where the blood supply to a segment of intestine is compromised. This may occur through internal hernias, pedunculated lipomas, and entrapments through mesenteric tears or natural openings. A torsion refers to a twisting of the intestine about its long axis, which can also compromise blood supply and intestinal lumen patency.

When blood flow is reduced, the affected tissue becomes ischemic and begins to die quickly. In the horse, large sections of the bowel are either loosely suspended or unattached which makes these events more likely. Early signs can mimic milder colic, and so early reporting is critical. These lesions are surgical emergencies, and the affected intestine can become necrotic and leak bacteria and toxins into the abdomen.

Colic is an emergency. If you suspect colic, call your vet immediately. Move the horse to a safe, enclosed area for close observation. Remove all food from the stable. Manage violent rolling carefully. Encourage the horse to stand or walk gently to reduce the risk of injury but take care to never put yourself in danger.

A typical examination will include an assessment of the heart rate, temperature, mucous membranes and capillary refill time, skin elasticity, auscultating the gut sounds, rectal exam and passing a nasogastric tube. The rectal exam attempts to diagnose the cause of colic by internal palpation through the rectal wall. Sedation is often required, and reach is limited, but the examination often provides essential information that may be definitive in determining if surgical intervention is likely to be required. Nasogastric intubation involves passing a tube into the stomach via the nasal passage. It serves as both diagnostic and therapeutic tool that allows the detection of gastric reflux, decompression of the stomach and the administration of fluids. This is particularly important because horses are unable to vomit, and fluid accumulation can cause the stomach to rupture. The colic work up may also invariably include taking bloods, performing an ultrasound examination, and performing a belly tap.

Treatment depends on the cause and severity. Pain medication is a key treatment modality, and response to medication helps to gauge the severity of the colic. Fluids and electrolytes may be administered via a nasogastric tube for impactions. If colic signs persist or recur, or if certain findings are identified during a clinical or rectal examination, horses may require referral to a hospital for colic surgery. The decision to refer a horse balances severity, prognosis, and practical considerations.

Colic is among the most common and potentially serious emergencies of the horse. By recognising the signs early and promptly contacting your vet, you can give your horse the best possible chance of a successful outcome.