Researchers from the Chinese Academy of Sciences (CAS) have observed some differences in the behaviors of mice that completed a space journey and returned to Earth one month ago.
Four mice were sent into space aboard the Shenzhou-21 crewed spaceship on Oct 31 and were housed in a specialized habitat on the space station before returning to Earth on Nov 14. Of these four mice, one female has now successfully given birth to healthy offspring on Earth.
To measure the impact of life in the space on mice, researchers have arranged a family of mice born and raised on Earth as a control group. The female mouse in the control group has recently gave birth to several pups.
The researchers respectively set up a red room inside their cages. Through continuous 24-hour video monitoring, they identified behavioral differences between the space group and the ground control group.
"Since the mice returned from space mission, we have found that these space mice are more dependent on the red room than the ground mice. The male mouse of the control group helped the female mouse build their nest or at least left them alone after the female mouse gave birth to their offspring. In contrast, the male mouse of the space group pushed the pups out. The female mouse noticed this immediately, carried the pups back, and filled the openings on the red room right away," said Wang Yixi, an engineer at the Institute of Zoology (IOZ) of the CAS.
"We found that the female mouse of the space group has kept her babies inside the red room. She used the cotton to fill the openings on the red room in order to protect her pups. In contrast, the female mouse of the control group tends to be more carefree; she gave birth to her pups on the cotton-made nest outside the red room. So we reckon that she [the female mouse of the space group] is in an adaptive phase to the ground environment, which she finds intimidating, and she wants to protect her offspring," said Wang Hongmei, deputy director of the IOZ.
Wang said that preliminary observations suggest that after a period of living in space, the female mouse appears to have a stronger instinct to protect her offspring. Meanwhile, the male mouse seems to retain a sense of crisis from its recent experience in a weightless environment, making it resistant to the pups.
"These pups will grow up. After they grow up, we will continue to let them to breed their offspring. By monitoring their physiological and biochemical indicators, we hope to understand the long-term effects of the space environment on multiple generations of mammals," said Wang.
"Mice astronauts" found act differently from earth mice: researchers
