The zoo said Tuesday that 9-year-old Jiao Qing was examined last week by experts at the city's Leibniz Institute for Zoo and Wildlife Research after the discrepancy was picked up on an ultrasound.
The 110-kilogram (243-pound) bear underwent the scan while under anesthesia. Doctors confirmed one kidney is smaller.
The panda's urine will be tested to determine whether the smaller kidney is functioning properly. Even if not, animals can live healthy lives with only one kidney.
Jiao Qing is the father of twin cubs born Aug. 31. They are doing well.
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