It's a life or death situation now, and horse-man or not, Dan does not want to die. So he does the only sensible thing he can think of at the moment.
With a sharp movement, he stands up to his full height and clobbers the farmer in the head with hoof-punch, knocking the man clean out and sending him sprawling onto the ground.
No time to stay and make sure he's alright. He was going to have Dan killed anyway, so why should he care about whether or not he's alright? Now is the time for self-preservation, so Dan runs for it, bolting out into the countryside, knocking off the trappings of domestication as he goes.