Gabriela Mastromonaco, the zoo's curator of reproductive programs, says Er Shun, one of the pandas on loan to Canada from China, was artificially inseminated on Sunday.
Mastromonaco says the male panda, Da Mao, is too young for breeding, so sperm was flown in from China for the procedure.
She says the pandas only have one chance per year when they can breed and the breeding window lasts just one to three days, so the zoo had been preparing for the insemination for two to three weeks.
Mastromonaco says hormone tests showed Er Shun was ready on Sunday morning and the team was called in for the procedure, which she says was a Canadian first.
She says it's hard to tell when pandas are pregnant, so the zoo will be treating Er Shun as though she is pregnant at least through the summer.
"We'll treat her as if she is a pregnant female and give her everything she needs, make sure she maintains her weight ... whatever she craves," Mastromonaco said Wednesday.
"It's the first panda breeding in Canada," Mastromonaco said.
"And we knew, that was Sunday morning, that the insemination would have to happen that day, within hours," she said.
"We were very lucky," Mastromonaco added. "We had brought in the shipment of sperm from China and it had arrived Friday at midnight ... so the timing was quite tight."
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