I was checking my boy Terrance out today for hair rings, and noticed staining near his butt/bottom of his tail. I believe it is urine, but some parts seem brownish in color. My boys have normal poo and appetites. I just wasn't sure if this was a concern or not. My boys had a health check up about three weeks ago, because they had been making sneezing noises that concerned me. My vet told me it was probably my white chin being a sloppy eater. He had hay up his nose, and food in his whiskers at the vet. I felt so silly not noticing it! Both boys were in perfect health. I would just rather be safe than sorry concerning this staining.