Oh, sure--why not? They eat rats in India. People eat squirrels here in the US--squirrels are, in fact, rodents.
They eat guinea pigs in South America. I imagine that capybara are pretty tasty, too. Heifer, International used to have guinea pigs on their available animal gifts list, though I don't see them there at the moment. A trio of cavvies can produce a lot of offspring, and guinea pigs are good eating.

I wouldn't eat an FT rat. It's been killed and frozen with all of its innards intact, and that doesn't seem safe. I would slaughter and properly clean a live rat, instead. I'll bet that with some rosemary and a bit of a wine sauce, it would be absolutely delicious. Or, you could cook up a bunch of them, debone them, and make a hearty stew with potatoes and veggies. I don't know what rat tastes like, but I don't imagine that it tastes bad--most meats from mammals taste just fine. Diet will probably make a difference in the flavor. I imagine rats eating lab block will taste a lot better than those eating dog food, and rats that are largely grain fed would have a good flavor as well.