From the time he was an adolescent, humans had thrown stones at Walter, shot guns at him, and repeatedly tried to poison him with some strange-smelling food, which he had been wise enough to avoid. They had kicked at him, screamed at him, and once - at the very sight of him - a young woman had fainted. Walter had never been able to understand the horror he and his relatives aroused in humans. These, after all, were the same people who kept hamsters and guinea pigs as pets. The same children who loved white mice. These were the people who fed squirrels in the park and walked tiny dogs on leashes. As far as Walter was concerned, animals were animals - all of them equally important.If you like sweet books about animals then you should really read this one. And if you want to learn a little bit about rats, you will learn a bit here and here.
Walter The Story of a Rat by Barbra Wersba