Horse Loss of Appetite: Causes, When to Call the Vet & What to Check

Loss of appetite in horses has many possible causes, and some are urgent. Colic is one of the most important to rule out. Horses with colic may eat less or stop eating entirely, and they may also paw, look at their flank, stretch out, sweat, lie down more than usual, or produce less manure. Even mild early colic can look subtle, so a horse that is off feed should always be watched closely.

Mouth pain is another common reason a horse will not eat well. Dental disorders such as sharp enamel points, broken teeth, infection, diastema, or other painful oral problems can make chewing uncomfortable. You may notice quidding, slow eating, dropping feed, bad breath, drooling, blood-tinged saliva, head tilting while chewing, or reluctance to eat grain or hay. Some horses swallow poorly chewed feed, which can increase the risk of choke or indigestion.

Stomach disease can also reduce appetite. Equine gastric ulcer syndrome can cause poor appetite, mild weight loss, poor body condition, attitude changes, and intermittent abdominal discomfort. Stress, stall confinement, travel, illness, and high-concentrate feeding patterns can all play a role. In adult horses, ulcer signs are often vague rather than dramatic.

Other causes include choke or swallowing problems, fever or systemic infection, parasite burdens, liver or kidney disease, pain elsewhere in the body, heat stress, and sudden feed, herd, or housing changes. Some horses also eat less when stressed by isolation or social disruption. Because the list is broad, appetite loss should be treated as a meaningful warning sign rather than a minor inconvenience.

See your vet immediately if your horse is off feed and also has colic signs, repeated lying down, rolling, abdominal distension, retching, feed or saliva coming from the nose, trouble swallowing, marked depression, fast heart rate, fever, diarrhea, or very little manure. These combinations raise concern for problems like intestinal obstruction, severe colic, choke, significant dehydration, or systemic illness. A horse that suddenly seems painful and then becomes quiet can still be in danger.

Call your vet the same day if your horse skips more than one meal, eats much less than normal for several hours, starts quidding, drops grain, resists chewing, or shows weight loss, dullness, or reduced water intake. This is especially important in older horses, horses with a history of colic or ulcers, and ponies or easy keepers, because prolonged reduced intake can create additional metabolic risk.

You may be able to monitor briefly at home only if the appetite dip is mild, your horse is bright and comfortable, drinking normally, passing normal manure, and has no signs of pain, choke, fever, or respiratory distress. Even then, monitor closely for the next few hours, not days. If the horse does not return to normal eating quickly, contact your vet.

At home, check what and how much your horse is refusing, whether hay is easier than grain, how many manure piles are being passed, whether water intake is normal, and whether there are signs of mouth pain or nasal discharge. Take a temperature only if you can do so safely. Do not give medications unless your vet tells you to, because pain relief can mask worsening colic.

Your vet will start with a history and physical exam. Expect questions about when the appetite change started, what feeds are being refused, manure output, water intake, recent travel or stress, dental history, deworming, medications, and any signs of colic, choke, fever, or weight loss. The exam may include temperature, heart rate, hydration status, gut sounds, abdominal pain assessment, and a look for oral or nasal abnormalities.

If colic or choke is a concern, your vet may recommend urgent diagnostics and treatment right away. In horses with suspected colic, nasogastric intubation can be both diagnostic and lifesaving. Depending on the case, your vet may also perform a rectal exam, bloodwork, abdominal ultrasound, or other imaging. If dental pain is suspected, a sedated oral exam may be needed for a full look at the teeth and soft tissues.

Bloodwork is often used when appetite loss is paired with fever, depression, weight loss, or concern for organ disease. This can help look for inflammation, dehydration, anemia, electrolyte changes, and liver or kidney problems. Fecal testing may be considered in some horses, especially when parasites, diarrhea, or chronic weight loss are part of the picture.

Treatment depends on the cause. Options may include pain control, fluids, stomach tubing, dental care, ulcer therapy, diet adjustment, or referral for hospitalization or surgery if the problem is severe. Your vet will match the plan to your horse's exam findings, risk level, and response to initial care.

Home care should focus on observation, safety, and following your vet's instructions. Keep your horse in a calm environment with easy access to clean water. Track exactly what is being eaten, what is refused, and how much manure is being passed. If your horse seems interested in forage but not grain, note that pattern and share it with your vet, because it can help narrow the cause.

If your vet says it is appropriate, offer small amounts of familiar, appropriate forage rather than large meals. Some sick horses will eat better when offered small amounts of different suitable feeds to test palatability, but any feed change should still be thoughtful and not abrupt. Do not force-feed, syringe large amounts by mouth, or give oral products to a horse that may have choke or trouble swallowing.

Watch for worsening signs such as pawing, flank watching, rolling, drooling, quidding, nasal feed discharge, fever, dullness, diarrhea, or reduced manure. If any of these appear, or if your horse continues to refuse feed, contact your vet right away. Horses can look only mildly off at first and still have a serious problem.

Avoid giving leftover medications or pain relievers unless your vet specifically directs you to. In horses, masking pain can delay recognition of a worsening colic episode. Early reassessment is often the safest and most cost-conscious step when appetite does not return quickly.