Workers at the National Zoo are continuing to care for one panda cub while the other is safely in the care of its mother—but it appears Mei Xiang has decided she is "not a willing participant" in the zoo's swapping program, reports Smithsonian. Since the twin cubs' birth on Saturday, zoo officials had been swapping the newborns between an incubator and their mother every four hours to ensure proper care; when twins are born in the wild, a panda mother cares for the stronger one and leaves the other to die, reports the Washington Post. But yesterday, the zoo announced Mei Xiang has been refusing to let workers switch out the panda cubs since 2pm on Monday, leaving the larger cub, which weighed 138 grams at birth, in her pen, and the smaller cub, weighing 86 grams, in the care of veterinarians.
Though the larger of the siblings probably isn't in any danger—Mei Xiang is a "good mother," keepers say—the smaller cub is more of a concern. The newborn's weight has been fluctuating since birth and the cub has had digestive problems, regurgitating some of its food, per ABC News. Digestive issues could lead to breathing issues, but experts say there's no warning signs for that yet. The "panda team" is bottle- and tube-feeding the cub and administering antibiotics and an electrolyte solution under the skin to provide fluids and nutrition. So far, the little cub is doing well, but this is still a "high-risk period," veterinarians say. Zoo keepers are continuing their attempts to switch out the cubs every four hours, though there's no word yet on whether an attempt in the last 20 hours has been successful.