Space mouse gives birth to first generation of pups, opening doors for future research

One of the four mice that traveled aboard China's Shenzhou-21 spacecraft has successfully given birth to healthy pups after returning to Earth, the Technology and Engineering Center for Space Utilization at Chinese Academy of Sciences (CAS) said on Friday.

The four mice were sent into space on October 31 for survival and adaptation experiment under the space environment. They lived in a specialized small mammal habitat onboard China's space station.

After their return to Earth on November 14, one female mouse conceived and later delivered nine pups on December 10, six of which are alive and thriving – a normal survival rate.

These "space mouse offspring" are now under the attentive care of researchers, with the mother exhibiting normal nurturing behavior, and the pups displaying strong vitality.

The mission proves that the short-term space flight has not negatively affected the mice's reproductive abilities, which also provides an extremely valuable sample for studying the impact of the space environment on the early development of mammals, said Wang Hongmei, a researcher at the CAS' Institute of Zoology.

The space journey of the mice was not all smooth.

Due to adjustment to the Shenzhou-20's return plan, the mice faced a food shortage challenge for the extended period. In response to the unexpected situation, the ground research team quickly activated the emergency response mechanism, immediately conducting multi-plan demonstrations and ground verification.

Utilizing the external water supply interface on the space station's feeding system, the research team, in collaboration with the in-orbit astronauts, was able to pump water into the mouse habitat.

For the mice's food, the researchers identified several potential substitutes from the astronauts' food list, including compressed biscuits, corn, hazelnuts and soy milk, and conducted verification tests on ground to ensure that the mice would accept the new food and that it would not harm their health. After careful evaluation, soy milk was selected as the best emergency food.

Relying on an AI behavior analysis system developed in advance, the research team was able to track the mice's movement, eating and sleeping status in real time, accurately predicting the progress of feed consumption to provide key data support for emergency decision-making.

The researchers will conduct systematic research on the pups, focusing on their growth and development curves, as well as changes in their physiological and pathological characteristics. They will also monitor the reproductive capabilities of these offspring and try to observe a second generation of the space mice, further exploring the potential impacts of the space environment on multigenerational heredity and development in mammals.