You walk into the stable and see your Thoroughbred pawing the ground, looking at his flank, and refusing his grain. Your heart sinks. Colic is a leading cause of death in horses, and Thoroughbreds, with their high metabolism and sensitive digestive systems, are especially prone. Recognizing the early signs can save your horse’s life.
Our editorial team has compiled this guide to help you identify colic signs specific to the Thoroughbred breed. Thoroughbreds are known for their ‘hot’ temperament and can mask pain until it becomes severe, so knowing what to look for is critical.
Why Thoroughbreds Are Prone to Colic
Thoroughbreds have a high metabolic rate and a relatively small digestive tract for their size. They are often fed high-grain diets to support performance, which can disrupt the hindgut microbiome. Their nervous temperament means they are more susceptible to stress-induced colic, such as from transport or competition.
Common triggers include sudden feed changes, inadequate water intake, and ingestion of sand or dirt. Thoroughbreds kept in stalls for long periods are also at higher risk due to reduced movement, which impairs gut motility.
Early Behavioral Signs in Thoroughbreds
Because Thoroughbreds are often stoic, early signs may be subtle. Watch for a loss of interest in food, especially if your horse normally eats eagerly. They may stand apart from herd mates or lie down more than usual, but get up quickly if approached.
Other early signs include yawning, stretching as if to urinate, and curling the upper lip (Flehmen response). A Thoroughbred that normally has a bright, alert expression may look dull or anxious.
Physical Signs to Monitor
As colic progresses, you may see pawing at the ground, kicking at the belly, or looking back at the flank. The horse may sweat excessively, even in cool weather, and breathing may become rapid or shallow.
Check for a heart rate above 40 beats per minute (normal for Thoroughbreds is 28-40). Capillary refill time longer than 2 seconds and dark red or purple gums are serious signs. Reduced or absent gut sounds on the right side (cecum) can indicate a blockage.
Breed-Specific Pain Behaviors
Thoroughbreds may display ‘head tossing’ or ‘stargazing’ (holding the head high) as a pain response. Some will grind their teeth or salivate excessively. Unlike draft breeds, Thoroughbreds rarely roll violently; they may instead lie quietly on their side (lateral recumbency) which is a red flag.
Because they are high-strung, a colicking Thoroughbred can become dangerous, thrashing or trying to escape. Always approach calmly and call a veterinarian immediately if you suspect colic.
When to Call the Veterinarian
Any sign of colic in a Thoroughbred warrants a vet call. If the horse has not passed manure in 12 hours, has a heart rate over 60, or shows signs of shock (cold extremities, weak pulse), it is an emergency. Do not wait to see if the horse improves.
While waiting for the vet, remove all food but provide fresh water. Walk the horse gently if it is safe, but do not force movement. Do not administer any medications unless directed by your veterinarian.