Rachel staggered back as the spray hit her face.
"No, not you too!" Alice was in shock, having just seen Patricia turn into a donkey and knowing that Rachel would soon be following her.
"Oh, don't worry. You'll be joining your friend!" The zookeeper laughed as she squirted Alice with the same spray. Alice and Rachel could only watch as their changes began to begin.
Rachel was the first to show signs of the change. A low groan emitted from Rachel's mouth as her eyes drifted to her mother's donkey penis. As she focused on the appendage, a tent began forming in her undergarments and extending in length. Unlike her mother, Rachel was wearing a skirt that provided no battle for her lengthening member. It wasn't long before Alice was looking at Rachel's sizeable penis peeking out from under her skirt.
Alice was distracted from the view by her own change. She could feel a pulsing feeling coming from her nether regions. Having seen various victims of the zoo's contagion, however, Alice pushed back against the change. Just as she began thinking she was forcing her changes off, she caught sight of a something on the corner of her vision.
A mare had been let out from the zoo carrier and led to the front of the lawn by members of the zoo staff. Alice's parents were also led out from her backyard. All three horses looked as though they had regained some element of human thought. Her stallion mother in particular looked worried at the changes that were about to be imposed upon Alice. Alice's attention focused in on the new mare. The horse she knew to be her brother.
"Well isn't this nice. A proper family reunion isn't it." The zookeeper laughed as she watched Alice fall further to her changes.
Alice quickly became intoxicated by the scent of estrus seeping from her brother's horse vagina. This scent propelled Alice's changes forward. The pulsing returned with renewed force. Eventually, Alice's damn broke. With a low groan, a penis surged forth from her vagina, tenting out the shorts she had been wearing. Next to her, Rachel was not faring much better.
Rachel had also caught whiff of the intoxicating smell. Having already surrendered to her growing lust, the smell accelerated her changes further. Rachel's penis surged past her skirt and stood at full attention in the open air. With a sound resembling a mix between a bray and a moan, Rachel ejaculated all over the surrounding yard. As with her mother, Rachel's hands fell to her new member as she began stroking it. A second and third moan escaped Rachel as she orgasmed again and again.
Meanwhile, Alice was doing no better. Her penis had reached the limits of her shorts and was starting to tear through the fabric. With a loud pop, two balls fell from her vagina, sealing her masculine gender shift. The testosterone produced from the new genitals was all her equipment needed to punch through her shorts and into the open air. Alice watched in shock as the penis and balls of a stallion presented themselves to the world. Then her changes reasserted themselves. Alice came almost instantly, fertilizing the surrounding yard with her
semen.
The zookeeper stepped back, watching both girls humping the air furiously as they ejaculated over and over again. She grinned as a donkey tail lifted the back of Rachel's dress and a stallion tail ripped the seat of Alice's shorts. Both girls' muscles grew in size as they became more masculine in appearance. Shoes were torn apart as feet became hooves. Shirts were torn from chests, exposing dwindling breasts. Eventually, with one last spectacular orgasm, the changes neared completion as both girls fell to the ground and arms became legs.
Unfortunately for Alice and Rachel, the lack of arms and hands meant there was no means to pleasure themselves. Rachel tore the remainder of her skirt off and wandered over to her mother, both donkeys in a state of extreme lust but without the ability to sate it. Alice, however, had a very available means of sating her needs.
With a surge of strength, Alice threw herself towards her brother-turned-mare. Her brother's eyes went wide as he felt his sister mount him and thrust her new penis at his horse vagina. Alice ignored her watching parents as she began humping relentlessly at her brother's mare pussy. She was in ecstasy, unable to process anything else except the pleasure pushing her changes. With one last thrust, and a loud whinny, Alice ejaculated into her brother's horse pussy, filling it with her seed. Alice the stallion pulled herself off the mare that had once been her brother and wandered around the yard in post-orgasmic bliss.
The zookeeper looked around the yard at its inhabitants and the gender disparity. She turned to the new horny donkeys. "I think we're a little mismatched here aren't we girls. Don't worry, I'll find some new mates to even the numbers out."
The woman wandered over to a side house to find new victims.