A mum says she was left in 'total disbelief' after the Golden Retriever she bought as a female was found to have both male and female organs - and now needs a 'sex-change' operation to stay healthy.

Emma Priest, 36, from Stratford Upon Avon, brought home fluffy Penny last September as a therapy dog for her two disabled children.

But when the eight-week-old pup explored her new home, Emma's husband Matt saw something 'not quite right'.

Days later, a vet broke the news that the 'female' pup they'd bought had a fully functioning testicle.

Penny was born intersex - traditionally called 'hermaphrodite' - a rare condition in which she has one testicle and one ovary.

She also has half a womb and a single fallopian tube, with parts of her reproductive anatomy sitting externally midway up her abdomen rather than between her back legs.

The unusual case has sparked intense interest among vets, who say they still can't state Penny's sex with full certainty.

Now, as she launches a GoFundMe to raise the £1,000 needed for Penny to have the 'bonus ball' removed, Mrs Priest told the Daily Mail she was stunned to hear of her pup's condition, which she claims affects just one in every 100,000 canines.

Emma Priest has told of her 'disbelief' at discovering her new dog, Penny, had both male and female genitalia

Penny the Golden Retriever became the newest addition to Mrs Priest's family last September

She was initially bought as a 'therapy dog' for her Mrs Priest's two disabled children, who have autism and ADHD

Penny was born as a hermaphrodite, an extremely rare condition which means she has a sperm-producing testicle and one functioning ovary which produces eggs

She said: 'We were in total shock because even now the vets are not really able to confirm what sex she is.

'You take it to the vet thinking you've brought a girl and to be told that they couldn't give us an answer as to whether she was a boy or a girl was just total disbelief, really.'

Though Penny's novelty has further endeared her to Mrs Priest's family and their loved ones, it has posed extreme health risks which could be problematic should the pooch not have surgery.

Due to the location of her undescended testicle, which vets believe to be wrapped around her lymph nodes, Penny is at risk of cancer.

The poorly pup has also suffered with complications from Giardia, a parasite which invokes sickness, and the bacterial infection Campylobacter, since Mrs Priest first took her home.

The mother-of-two said it is unclear whether Penny's sickness - which also saw her hooked to an IV drip at just 12 weeks old - have descended from poor breeding, or if it is related to her hermaphroditism.

With vets unable to clarify such questions and the original breeder not claiming responsibility, Mrs Priest says her focus is now on getting Penny happy and healthy.

Mrs Priest said: 'The only way that is going to happen is for her to have this huge surgery, because they've said it could be catastrophic if we leave her any longer.

Mr Priest was the first to spot that something was not quite right with their new pup

Penny., who has a sperm-producing testicle and a functioning ovary which produces eggs, also has half a womb, half a uterus, and one fallopian tube

Due to the location of her undescended testicle, which vets believe to be wrapped around her lymph nodes, Penny is at risk of cancer

The pup has been poorly ever since Mrs Priest brought her home - and is facing an invasive spay surgery on October 16

'The vets are quite confident that, because the external part is female, although it's in the wrong place, then she will lead a female life once her insides have been taken out.

'But they still don't know, which I guess these days is cool to be non-binary. But from a medical point of view, we just want her to be healthy and to be able to lead the most healthy life she can.'

As Penny's condition is classed as a 'birth defect' by vets, funding surgeries does not come under Mrs Priest's pet insurance, meaning she has forked out 'thousands of pounds' over the last year.

Despite the financial burden, Mrs Priest says she just wants the invasive spay, scheduled for October 16, to pass without problems - marking the end of what has been a 'horrible year' for Penny.

Her worries have not been alleviated by vets' warning that they may have to 'rip her open' if they are unable to remove the testicle laparoscopically - but the mother-of-two is desperate for a positive outcome.

She said: 'We're dreading it. We really are dreading her having to go, but from a health point of view, she has to have this done.

'She's so incredibly special and she's our world. We absolutely adore her'.

Our new golden retriever needs a £1,000 sex change