Hopefully they won't be bubonic flea rats.
This is interesting, especially given rats' ability to chew through wires and other stuff like that. I could see the rats chewing into it and if they couldn't get through the case, then at least marking it.
I heard they started with dogs, but they kept retrieving the mines and dropping them at their feet.
They need to put reflective tape on the rats and use the laser disposal system. Once the rat indicates the mine, they can get its position off the reflective tape and then signal the rat to run.
Could be the next big TV game show. Blast the Rat!
Just a thought.