Both but running isnt a gait in horses =)
The horse had trotted across the grassy field.
Trotted.
A Sentence for trotted is - The horse trotted down the road or field
trotted skipped sailed flipped drove and ran
The adventurous man trotted his horse off to the west into the sunset.
Both could be used in different situations: The horse ran fastest of all the horses in the race. The horse ran faster than all of the other horses. When the man, the horse and the dog ran, the horse ran fastest. The horse ran faster than the man and the dog.
horses
Hearing the commotion, the remaining militia rushed to the village at a trot.Urged on by its rider, the horse broke into a trot.
The jogger trotted
The horse trotted along placidly- it and its rider were in no hurry at all.
"Is run" is correct. "Is ran" is not grammatically correct.
Bolted Sped Hurried Galloped Frolicked Trotted Scurried Darted Sorry, that's all I can think of