Flared or Widened Nostrils
Look at the signal, then look at the whole horse and the situation around it.
NOTICE
The nostril openings become larger or more open than usual.
The change may be brief, or it may continue for a while depending on what the horse is doing.
WHAT IT MAY TELL YOU
Widened nostrils can show up for many reasons. A horse may be exercising, breathing more deeply, highly alert, aroused, investigating something, or experiencing discomfort.
DON'T ASSUME
Flared nostrils do not automatically mean fear, excitement, pain, or breathing trouble.
LOOK AGAIN
Ask what was happening just before the nostrils widened.
Is the horse exercising or recovering from exercise? Is the breathing faster or harder? Are the eyes wide or the body tense? Or is the horse simply standing quietly and taking in something new?
Research / Learn More
What research suggests
Nostril dilation is a visible facial action in horses and can appear in different situations. Some EquiFACS pain studies have also found it more often in horses experiencing pain.
What that does not mean
Widened nostrils by themselves do not identify the cause. Exercise, arousal, pain, and increased breathing demand can all change the nostril opening.
Sources
- EquiFACS — defines nostril dilation as a visible facial movement without assigning a single meaning to it.
- EquiFACS for pain-related facial responses — found nostril dilation among facial actions that were more prevalent in painful horses.