You You

Basic Profile

You You (Chinese: 优优, “Excellent Excellent”), studbook number 474, was a female giant panda born on August 3, 1998 at the China Conservation and Research Center for Giant Pandas (CCRCGP) Hetaoping Base in Wolong, Sichuan. Her mother was Ying Ying (英英), a wild panda from Sichuan, and her father was Lin Nan (林楠), a wild panda from the Baishuijiang region of Gansu Province.

She was one of the most scientifically significant pandas of her generation — not for the number of her offspring (though she had 9), but for the reproductive breakthroughs she enabled.

Siblings

You You had 12 siblings through mother Ying Ying: Liang Liang (亮亮), Yang Yang (阳阳), Mei Qing (梅清), Lan Xiang (兰香), Ying Mei (瑛美), Ying Hua (瑛华), Xian Nv (仙女), Xian Zi (仙子), Meng Meng (萌萌), Yun Yun (韵韵), Shu Qin (淑琴), and Sen Sen (森森).

Offspring

You You gave birth to 9 cubs, forming a significant maternal lineage:

Scientific Contributions

World Record: 5 Matings (2005)

On April 29, 2005, You You and male panda Ying Ying (迎迎) were paired for breeding for the first time. In a single session, they mated five times — setting an official world record for the most natural copulations between captive giant pandas in a single day. The record was published in the international studbook records and cited as evidence that natural breeding could be highly successful when the pair was well-matched.

First Frozen Semen Cub (2009)

On March 20, 2009, researchers artificially inseminated You You using frozen semen collected from male panda Lu Lu (芦芦). At the time, frozen semen had never successfully produced a giant panda cub.

On July 23, 2009, You You gave birth to a healthy male cub — Xiang Lu (香芦, studbook 747) — the first giant panda cub in the world conceived through frozen semen artificial insemination. The breakthrough was published as a major advancement in panda reproductive technology, demonstrating that sperm could be cryopreserved, stored, and successfully used for AI — opening the door to genetic exchange between geographically distant populations.

Artificial Rearing and Cub-Swapping (2016)

In December 2016, at the CCRCGP’s Shanghai base, You You gave birth to a pair of twins. For the first time, the Shanghai team successfully applied artificial rearing combined with cub-swapping technology — alternating the cubs between the mother and incubators to ensure both received maternal care while allowing keepers to monitor their health. By their one-month checkup, the twins had grown to 1,350g and 1,168g respectively, with strong limbs and good developmental indicators.

Life Journey

Early Years (1998–2005)

You You spent her early years at the Wolong Hetaoping Base. She was transferred to the Ya’an Bifengxia Base on May 23, 2008, shortly after the Wenchuan earthquake.

Productive Decades (2006–2016)

Her breeding career spanned a productive decade from 2006 to 2016. She moved between Hetaoping, Bifengxia, and the Shanghai Wildlife Park (from September 3, 2016), where she gave birth to her eighth and ninth cubs.

Final Years (2018–2025)

On February 9, 2018, You You was moved to the Wolong Shenshuping Base. By late 2024, now 26 years old, she began showing signs of reduced appetite and digestive weakness. Veterinary tests revealed chronic kidney failure with anemia. Despite intensive treatment and collaboration with renal specialists from leading hospitals, her condition deteriorated.

On the night of March 12, 2025, You You collapsed and stopped breathing. Emergency resuscitation revived her temporarily. On March 13, she collapsed again. Despite continuous抢救 (resuscitation), she passed away at 9:55 AM on March 14, 2025.

Her keepers wrote in their memorial: “You You, you were so strong and brave. We saw in your eyes the will to live. You ate when we asked you to. You took your medicine. You cooperated with every examination. You were so good. Rest now.”

Legacy

You You’s contributions to panda conservation extend far beyond her 9 offspring. The techniques pioneered through her — frozen semen AI, artificial rearing, and cub-swapping — are now standard practice across all major panda breeding centers worldwide. Every cub born through these methods is, in a sense, part of her legacy.