Ariel, the six-legged dog found dumped in a supermarket car park, has had surgery to remove her extra limbs.
The 11-week-old spaniel hit the headlines after being abandoned outside a Pembrokeshire branch of B&M in September.
About £15,000 was raised by well-wishers all over the world, enabling her to have a life-changing operation.
Surgeons also managed to save all four of her "normal" limbs after fears one might have to be amputated as well.
Mikey Lawlor is the founder and manager of Greenacres Rescue near Haverfordwest, which took in Ariel after she was discovered alone, skinny and in a state of distress.
"The vet who initially assessed Ariel noted that, in addition to her two surplus back legs, she also had an additional vulva," said the 42-year-old.
He added that a CT scan later revealing she only has one kidney upped the complexity of the medical treatment required.
"And, due to having two hip joints on one side, Ariel's pelvis never formed properly.
"As a result her normal back right leg had virtually no muscle tone, so there was a possibility that might have had to come off too.
"Thankfully that wasn't the case though as it's shown signs of having strengthened a lot in recent months."
Named after Disney's Little Mermaid character, because her partially fused extra back legs resembled a mermaid's tail, Ariel was operated on at Langford Vets Small Animal Referral Hospital in Somerset on Thursday.
"There were two procedures which lasted about two hours, but both went fine," said Mr Lawlor.
"The next day she was up, walking around and eating and drinking.
"Now we just need to keep our fingers crossed she doesn't get any infections, but she really is in the best hands."
Mr Lawlor said he hoped Ariel would be discharged this weekend to return home to her foster family in west Wales.
"Then, after she's had several weeks of physiotherapy and recovery, we'll see about finding her a forever home," he added
"The response we've had to Ariel's story so far, including calls and emails from as far away as New York and Australia, has been incredible - so I've no doubt she'll be snapped up.
"I just can't say enough of a thank you to everyone who's contributed to helping her."
Langford Vets' hospital director Vicki Black added: "Ariel was a complicated little dog whose care required close collaboration across a number of our specialist teams, including orthopaedics, soft tissue surgery, anaesthesia and radiology.
"As part of the University of Bristol we are a centre committed to career-long learning and are proud to innovate and treat pets like Ariel.
"We are delighted such a lovely animal has recovered well from her surgery."
