She is a 25 yr old Appaloosa mare. She is in a field with six other mares. Yesterday and today she has started agitated head tossing, then randomly trotting off by herself. She pays no attention to the other horses. She trots out about a 100 yards, stops for a few minutes, then repeats. She will keep this up for hours. She'll stop for 10 minutes or so and eat out of the hay feeder, then start up again. The pattern seems to be the head tossing first, then the trotting. She's normally a lazy old horse so this behavior is completely out of character.
She is not sweating or acting as if she has colic. She's stabled at night - she ate up her hay and her stall was normal this morning. She was on bute for five days for a sprained fetlock - the last bute dose was Monday morning and this behavior started Monday afternoon. She's been on bute before and not behaved like this.
Has anyone had any experience with this sort of behavior?