If the tail is moving back-and-forth very quickly, it may suggest that your horse is stressed out. Watch to see if there are a lot of flies or other insects present, if this is the case, your horse’s tail movement may simply be an effort to swat them away.

If nickering becomes more intent, high pitch, or seems stressed, it could be a sign your horse is unhappy. [9] X Research source

Horses will usually bite onto stall doors, poles, or other hard objects when cribbing.

Skin conditions like ringworm, mud fever (associated with wet and muddy conditions), and cracked heels (similar to mud fever). Respiratory problems like a cold or a cough. To identify a cold or cough, listen for coughing sounds and watch for nasal discharge. Weight loss, which is often associated with stress. Unhappy horses can show some weight and muscle loss over time. Colic, which could be a result of many things, but almost always manifests in abdominal pain. [13] X Research source

Schedule regular appointments with your veterinarian. Your horse should see a vet at least once a year. Contact your vet if your horse has any sudden health changes. Talk to your vet if your horse seems lethargic, depressed, or otherwise unhappy.