Calgary Zoo could get panda twins

The Calgary Zoo has been preparing for the arrival of a panda couple, but it could be getting a panda family.

That's because the female giant pandato be loaned to the zoo from China in three years is pregnant with twins.

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"We're at a very early stage, we're cautiously optimistic," said Chris Dutton, head of veterinary services at the Toronto Zoo where the mom-to-be, Er Shun, is currently being housed.

Should all go well, Er Shun'stwins will be delivered in mid-October.

They will move to Calgary in 2018 with a male panda named Da Mao,however, zoo officials don't yet know if he's the father.

Er Shun wasartificially inseminated back in Maywith sperm from three different males Da Mao and two other giant pandas in China.

Dutton says the female panda hasbeen getting regular ultrasounds,which she's not opposed to as long as there's food involved.

"She lies down on her back with her arms and legs sort of stretched out and while she's being fed some apple, I reach through with an ultrasound probe and put it on her tummy and I can get a lovely image of her uterus," he said.

The zoo posted this video of the ultrasound images on YouTube.

'Panda swapping'

While it's not uncommon for giant pandas to give birth to twins, Dutton says in the wild the mother will often abandon one of the cubs.

"The Chinese have really been forward-thinking in this and they've developed this system of panda swapping. So what happens is when we have two baby pandas, we swap one every two hours with the other one with the mother...and that way we can raise two babies."

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A spokesperson for the Calgary Zoo says Canada's agreement with China always accounted for the possibility of panda toddlers.

China has agreed that the cubs will stay with their mother for a minimum of four years.

Panda-monium! Er Shun pregnant with twins

9 years ago

Duration 3:40

A giant female panda bear on loan to the Toronto Zoo from China as part of a breeding program, is pregnant with two cubs