You were in a sterile room that looked like some sort of lab before you were strapped down to a bed. You blushed a little when you realized that you were still naked and you had no idea what to think of all of this. You struggled to escape again as the two women left the room and the sound of hooves were heard and you looked up to see an anthro gazelle dressed like a doctor.
"Is everyone who works here an animal?" You asked as the gazelle laughed a little. "Why did I only see humans before?"
"Because you weren't one of us before," he said with a shake of his head as he looked you over. "Do you think we all started like this? We all started human but our boss developed the technology to transform people into animals. If you hadn't run then maybe we'd have gotten you a job in time."
You tried to growl at him but just let out a bray as he shook his head. "Well, you've already lost your ability to speak, so lets get this finished, shall we?"
He took out a needle and injected you with it before he stepped back to watch as your body started to tingle. You couldn't do anything but watch as your chest started to push out and your arms and legs started to elongate and form into equine limbs. Your fingers hardened and shrunk down to form your new forehooves.
As your breasts shrank into your body for a moment you thought that maybe you were changing back to a male, but instead you felt your vagina and anus adjusting position to be closer to where it was supposed to be. Your nipples moved down between your hind legs and formed into your new teats.
The transformation finished with your butt inflating out into your new equine proportions. You tried to struggle more as you felt a burning sensation in your loins. Your new Zebra mind was starting to get stronger as you fought against it, trying to push your human thoughts away permanently.
"Excellent, excellent, you're already in heat," the doctor said as you brayed in protest. "You better calm down, or do you want to lose your humanity once and for all? Though, maybe I will anyway."
He looked up at a strange device above you and you stopped when you realized that must be what he'd use. All he had to do was press a button and you'd be a Zebra mare in mind and body.
"Be a good mare and give us foals and we won't have to do this," he said with a smirk. "Then again, I might just save us a lot of trouble and do it now. What to do, what to do..."