Sarah thought about why it was so hard for her to decide what farm animal to become, and she realized it was because she kept second guessing herself. She knew what she wanted to be, even if she didn't know of anyone else going to Species Reassignment to become one.
"Well, I know it might seem like a rather tame choice, but it is okay if I'd really just like to be a dog?"
"Yes, absolutely," said the receptionist. "The nation's farms can never have too many work dogs. Most of our volunteers prefer something more exotic, but canine forms are as easy for our technology to accomplish as anything else. Just be aware, though, that you will probably be giving birth to numerous puppies at once if you end up as a breeding dog, and you will most likely be sterilized if you are placed in any role other than breeding."
Sarah let that thought sink in for a moment. She hadn't considered the possibility of being spayed. Would she be okay with losing part of what made her a woman, even if she were already a dog? She decided she would be. It's not like she would be having a human sex life anymore anyway. She was putting herself at the mercy of whoever owned her as an animal. If she could handle everything else that went along with that, then she could surely handle being sex-impaired work dog as easily as she could handle being a puppy factory.
"Yeah, that's fine," Sarah said. She signed dozens of papers and was taken into a room with one of those one-way mirrors and told to take off her clothes. She wondered who was watching her from the other side of that mirror. Probably some sleazy pencil-pusher with a government-sanctioned excuse to perv out, no doubt, but so what? Sarah knew she was legally a dog already and would just have to be okay with going around naked. In fact, she found it somewhat liberating not to have to worry about clothes anymore. She never did have her sister's fashion sense, and she hated being constantly judged for looking too prudish, too five-minutes-ago or too slutty.
A nurse injected Sarah's naked body with a glowing fluid and then left the room. A misty green gas came down out of the ceiling made her skin and lungs tingle. If she didn't know better, she'd think she was being executed. From a purely legal perspective, she might as well be. She was pleased, however, to watch black and white hairs starting to sprout from her arms, legs and chest. She looked at her reflection and watched her blonde hair turn black and white, even as new hairs started growing from her face. Watching her fur grow thicker, she decided it looked like she was going to be a border collie. This was all but confirmed when her face grew out into a snout and she could see her own black nostrils surrounded by white muzzle fur. She opened the muzzle and watched her tongue flop out: it was so long it almost looked silly! She brought her tongue back in and ran her hands through her tummy fur. It felt good, and it made one of her legs start to kick for some reason.
Realizing she could feel something hanging down over the back of the surgical table she was sitting on, she craned her neck around and got her first glimpse of the bushy black-and-white tail she'd be dragging along behind her wherever she went from now on. It looked and felt very limp at first, but she sensed that she knew how to change that. After a moment's decision-making about what she wanted her tail to do first, she spurred some new musculature to action and watched her tail raise up to stick out behind her. She practiced sending it around in random directions before giving it a break and letting it hang freely once more. She hoped she would be able to take care of her new tail: she thought she might be clumsy enough to get it stuck in doors or let some curious three-year-old get hold of it. Oh well, it's hers to live with now, for better or for worse.
Turning her attention to her hands, Sarah watched in awe as her thumbs and fingers started to shift. White fur finished growing in over her hands, but some spots of skin were left hairless on the undersides. The skin spots thickened up and hardened into an unmistakable doggy paw-print pattern, while her nails stiffened and rounded out before growing forward into hooked points. For a moment, it looked as if her thumbs were going to wither away to nothing, but they stopped just short of a complete vanishing act, leaving her with thumb-claws pointing to the space between her hands.
"Well, no more opposable thumbs," she thought. "No more texting randos, typing out pointless work emails, or holding a pencil for me."
Looking down at her feet, she saw the same thing happening down there. Her feet lengthened out into the bottom part of a dog's hind legs, while her legs shortened up into a pair of canine haunches. At the very end of her feet, she watched her toes sprout pads and claws the way her hands had. She would have reached out to touch them, but her hands had already changed to the point that she couldn't grasp things anymore. After a moment's thought, she remembered that she had a new tool for reaching out to touch things, and it was right up there in her mouth. Flopping her new tongue out, she lifted up a freshly changed hind paw and ran the moist pink surface across her leathery pads. She was surprised at how soothing it felt to do this, and it took her a few seconds to convince herself to stop. Just out of curiosity, she licked a front paw, too, before perking up and turning her attention back toward her reflection the one-way mirror. The realization that she was almost a dog now, free of her human shortcomings and ready to let a more responsible human make all her important decisions for her, made her happy. Feeling happy made her want to wave her tail around and even bang the table with it. Wagging that brand new bushy tail of hers made her look and feel even more like a friendly collie.
Focusing on her reflection gave her a chance to see widened ears growing upward just enough to lose control of their own weight a bit and start to bend a little at the tips. Her perky but slightly bent ears gave her a smart but playful look that made her proud of what she had become. Her blue eyes deepened to a rich golden brown, and her transformation was complete. She was seated on her haunches with her front paws holding her up in a sitting position, waiting expectantly for someone to come in and retrieve her so she could start her new life.