ABOVE: © ting pan
About a year ago, some—but not all—of the mice in Janelle Ayres’s lab at the Salk Institute for Biological Studies in La Jolla, California, got really sick. Ayres and her colleagues had infected each of the animals with the pathogenic bacterium Citrobacter rodentium, and within a few days, some of the mice began losing weight. Their colons became severely inflamed, and the animals died not long after. But other mice that were also exposed to the bacterium looked perfectly healthy.
All the mice were genetically identical. They were fed the same food, kept in the same kinds of cages, and had no notable differences in the composition of their microbiomes. “Yet half the animals died, and the other half survived,” exactly what she was aiming for, Ayres tells The Scientist.
There’s more to recovery than simply killing bugs.
This type of experiment is called “lethal dose ...
