On of my weaned rats looks as if they have blood around their nose. What is this? What can I do. I have 10 adult rats, and approx 35 kittens from pinkie to just weaned. Is this contagious? What can I do to treat them all without having to take them all to the vet? I am trying to build my colony right now and I don't want to put them down and have to start over, not to mention the infected rat I am most worried about is my 5 year olds beloved pet. Please help.