In 1990, Chengdu Zoo adopted the "twin swapping" method, successfully allowing twin cubs to survive. The success of this method dramatically increased the survival rate of giant panda cubs to 88%. As a routine management method for nursing giant panda twin cubs, it has been widely adopted by breeding institutions worldwide.

• Twins swapping
  What is twin swapping?

• When a giant panda mother gives birth to twin cubs, this method involves rotating the cubs so that each one can drink breast milk. One of the twins is taken from the mother and cared for in an incubator. The other cub stays with the mother to suckle. Then, the two cubs are swapped.

• Number of births (Number of cubs per litter

  

• Changes in Giant Panda Cub Survival Rates

  

  Created based on The 2019 International Studbook For Giant Panda

In 2003, a pair of giant panda twins was born at Adventure World. Their mom, Meimei, successfully raised both cubs at the same time, which was a first for pandas in captivity! Meimei gave birth to her second cub about 2 hours after the first one. She was really good at holding both of them (named Ryuuhin and Shuuhin) at the same time. The next day, when we weighed them, we noticed both cubs' poop was yellow, just like it should be from breast milk! So, we knew they were nursing well and decided to let Meimei keep raising both cubs naturally.
Usually, giant panda cubs lose a bit of weight after they're born, and then they gradually gain it back. It was pretty much the same for the twin cubs born at Adventure World in 2006, 2008, 2010, and 2014 – they only surpassed their birth weight 4 to 7 days after being born. But Ryuuhin and Shuuhin, born in 2003, were an exception! By their second day, they weighed 160g and 106g respectively. On the third day, Ryuuhin was 167g (up 7g from the day before) and Shuuhin was still 106g (no change), so their weight didn't drop at all, and they grew up smoothly. Both cubs reached about double their birth weight by their 11th day and were naturally breastfed for a full 7 months. Meimei had twins two more times after that. Her second cub born in 2005 weighed only 66g and passed away after just one day. The next year, she had another pair of twins: the first cub (named Eihin) weighed 196g, and the second (Meihin) was 84g, a huge difference of 112g! To make sure the smaller Meihin
could get enough milk, we had to use the "twin swapping" method. Experts believe the main reasons Meimei successfully raised both twins (Ryuuhin and Shuuhin) naturally in 2003 were her strong mothering skills, abundant milk production, and the fact that the two cubs' birth weights weren't too different. During this time, Japanese and Chinese experts gathered tons of behavioral data on giant pandas naturally raising twins, which gave us valuable experience for improving cub survival rates in the future. This 2003 case was even presented at the International Conference on Giant Panda Conservation as the first successful instance of a mother naturally raising twin cubs in captivity!

Ryuuhin and Shuuhin's Weight Changes