I am an animal lover, but I have no trouble killing rats. We once had our farm
invaded by them, and it was not a picnic. We used pressurized hoses to expel
them from their holes and then our dogs took on the job of eradicating them.
With a lot of persistence, we were successful. The survivors left. Rats enjoy
dirty conditions, are destructive and can spread disease. I'll save my
sympathy for more desirable critters.