The giant panda cub born a week ago at the National Zoo in Washington has died, saddening zoo officials and visitors who had heralded its unexpected arrival.

Mei Xiang tends to her panda cub at 5 days old (WJLA TV)

The officials say the 4-ounce cub, about the size of a stick of butter, had showed no obvious signs of distress and made its final recorded noise shortly before 9 this morning.

The cub's mother, Mei Xiang (may shahng), then made an unusual honking sound at 9:17 a.m. Her keepers interpreted that as a distress call. Staffers were able to retrieve the cub about an hour later.

The cub was not breathing and its heart had stopped. A veterinarian attempted CPR before it was pronounced dead at 10:28 a.m.

The cause of death is unknown. The cub appeared to be in good condition, and there were no outward signs of trauma or infection.

Suzan Murray, the zoo's chief veterinarian, says a necropsy is being conducted to determine the cause of death, and preliminary findings are expected Monday.

Zoo director Dennis Kelly calls the cub's death "devastating" for the entire staff.

The cub had been a surprise at the zoo. Fourteen-year-old Mei Xiang had five failed pregnancies before giving birth.


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