Toronto Zoo giant panda breeding attempt fails
Er Shun the giant panda did not get pregnant following an insemination in April.
Er Shun was inseminated in April
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One of the star giant pandas at the Toronto Zoo failed to get pregnant following a breeding attempt.
Er Shun was artificially inseminated in April, an attempt the zoo says led to "early signs" of a possible giant panda cub.
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But urinary hormone tests, ultrasounds and even behavioural observations show she didn't produce a cub.
Er Shun is one of two pandas on loan to Canada from China.
Officials at the zoo say there isn't a pregnancy test for the endangered animals but they still plan to share their research internationally to help breeding efforts.
Pandas have just a single chance each year when they can breed — a window lasting one to three days.