Jin Zhu (#437)

Basic Profile

Jin Zhu (Chinese: 锦竹), studbook number 437, was a giant panda born on August 12, 1996 at the China Conservation and Research Center for Giant Pandas (CCRCGP) Hetaoping Base. Her father was Pan Pan (盼盼) and her mother was Yong Ba (永巴).

Siblings

Jin Zhu’s siblings included Fei Fei (妃妃), Qian Qian (茜茜), Yuan Yuan (媛媛), Tian Tian (添添), Guo Qing (国庆), Long Teng (龙腾), and Long Fei (龙飞).

The Japan Years (2000–2002)

In 1999, following the devastating Hanshin Earthquake in Kobe, the Japanese government sought to boost public morale. A panda loan was proposed: two pandas would be sent to Kobe Oji Zoo as a symbol of recovery and friendship.

Jin Zhu — at the time identified as male — was selected alongside a female named Shuang Shuang (爽爽, later renamed Dan Dan/旦旦). Following a public naming campaign, the pair were renamed “Xing Xing” (兴兴, Jin Zhu) and “Dan Dan” (旦旦) — the names meaning “prosperity” and “dawn.”

They arrived in Japan on July 16, 2000.

The Discovery

In April 2001, Dan Dan entered estrus. The timing was perfect. Zoo staff monitored hormone levels, observed peak behavior, and prepared for a carefully timed mating. On May 1, they placed Xing Xing and Dan Dan together.

Xing Xing showed no interest. None whatsoever.

Puzzled, experts decided to attempt artificial insemination. When they sedated Xing Xing for semen collection, they made a startling discovery: there was no penis. The external genitalia were ambiguous — neither clearly male nor clearly female.

Recall and Diagnosis (2002–2005)

On December 5, 2002, Jin Zhu was returned to China. A replacement male, Long Long (龙龙, studbook 433), was sent to Kobe in her place.

In 2004, blood samples were sent to two independent laboratories — West China Medical University and Sichuan University — for chromosome analysis. The results came back: normal female chromosomes (XX). That same spring, Jin Zhu showed her first signs of being female.

In late 2005, a laparoscopic exploratory surgery revealed the full picture: Jin Zhu’s ovaries, fallopian tubes, and uterus were all normal and fully developed, but they were slightly displaced, compressed by intestinal membranes. Surgeons performed a repositioning procedure that lasted over two hours. It was successful.

Jin Zhu was, officially and finally, female.

Motherhood at Last (2007)

In March 2007, Jin Zhu mated naturally with male panda Yuan Yuan (园园) from Beijing Zoo. On August 6, 2007, she gave birth to twin daughters — Jin Xin (锦心, studbook 672) and Jin Yi (锦意, studbook 673) — at the Ya’an Bifengxia Base. These were the first giant panda cubs ever born at Bifengxia since the facility opened in 2003.

Third Cub (2011)

On July 29, 2011, Jin Zhu gave birth to a third daughter, Cao Gen (草根, studbook 812), at the Hetaoping wild training base. The birth occurred in a semi-wild enclosure — part of a pilot program to test whether captive-born pandas could successfully raise cubs in more natural environments before release.

Death (2014)

On October 14, 2014, Jin Zhu and her youngest daughter Cao Gen died together during wild training at the Hetaoping Base. The specific cause of death was not publicly disclosed.

Legacy

Jin Zhu’s case remains one of the most remarkable gender-correction stories in panda history. Her daughter Jin Xin (锦心) went on to become the mother of Rong Rong (荣荣) — the third confirmed offspring of the brown panda Qi Zai (七仔) — ensuring that Jin Zhu’s genetic line continues through one of the most famous lineages in the captive population.