I adopted my hedgehog at 7 or 8 weeks... and for about two months her urine smelled really, really bad. Burning nostrils bad... and I'm not usually sensitive to smells. But gradually, over another two months or so the urine smell tampered off and now, at 6 months, the smell is largely unnoticeable. Not sure what caused this, but it seems some others have had similar experiences with baby hogs. I'm fairly certain it wasn't connected to diet because the foods were kept fairly consistent (I added a new food to the mix, but removed none).