Some things we just do not know:
Saul journeyed near to Dmascus, light from heaven, fell to ground, heard a voice. Acts 9:3-4 That's about it. No mention of a mount (animal). Now the search engine may or may not be able to help us. Maybe tomorrow I can spend some time searching. And
the men which journeyed with him stood speechless, hearing a voice, but seeing no man.
Acts 9:7 (KJV) Each of the three accounts of Saul’s miraculous conversion (Acts 9:3-4, 22:6-7, 26:12-14) asserts that Saul, upon seeing the light from heaven, fell to the ground. The text mentions Saul falling down, not falling
off something.
So this may be one of those searches that will not result in anything. (Except maybe a lot of "
Rabbit Holes".
Tradition of men: (film and media
paint a picture of a Horse).
The imagery of a horse is a later tradition, popularized by Renaissance and Baroque artists like Caravaggio to add drama, as noted in
Wikipedia.
Wikipedia. There are art references that cause many to think Paul fell from his horse. One of the most famous of these is Caravaggio’s famous painting titled “Conversion on the Way to Damascus”.