You were nervous as you entered the offices of Farm Vacations, Inc. While the request you had made probably wasn't unique, you felt your face flush with embarrassment as your name was called. You were going to become a mare for a week.
It was a fetish. The idea of becoming little more than an animal, a female animal at that, turned you on. And you wanted the full experience. To be sent to a stable where the people there didn't know you used to be human. And to become a young mare about to go into heat, and to be mounted. More than that... you had agreed to the special stipulations that if your breeding resulted in a foal, your identity would be signed over to the company, to be sold to someone wanting a new life, while you would become company property. Another side business of theirs, under New Life, Inc., where you could buy a new life and identity. And, finally, you had requested mental modifications. You would have your human knowledge, though not memories, cordoned away unless you concentrated on them. The ability to read, the ability to properly process the passage of time in a human way, even your ability to understand language would only be available to you if really focused. It wasn't permanent, though other vacationers who had spent time with these mental modifications in place had reported it getting increasingly more difficult to call on them as time passed. As if their abilities atrophied, only to quickly come back once they turned back to human. They were talking several weeks or months, though, and you'd only stay a mare for a week. Hopefully.
Of course, you had requested that the mare you were to become had very low fertility. You wanted a tiny little risk of being stuck, it would make the experience all the more salient, but you didn't actually WANT to become a mare for life.
Once you were called, the employee meeting with you went over your details, asking you to confirm that this is what you wanted, and making sure you signed all the papers. They were utterly professional, and reassured you that you were far from the first man to come with similar requests. Some had even gone further than you, electing for permanent transformations, or electing to become the property of someone they knew - temporarily or permanently.
You swallowed the pill, and felt the transformation start. A moment later, you passed out, and the next thing you knew, you were in a horse trailer, on the road to the stables that would be your home for the next week.