They got this name from their political opponents, who charged that they were willing to burn down the barn to get rid of pro-slavery rats.

VOA: special.2009.03.05

The cow genome is more similar to humans than to mice or rats.

VOA: special.2009.05.05

It was a terrible slum -- as such places are called -- where too many are crowded together, where the houses and streets are dirty and full of rats.

VOA: special.2010.08.01

"When the research progresses to a stage when the information coming from mice and rats is not sufficient, we may move up to using monkeys.

VOA: standard.2010.02.16