Hi, one of my girls used to have a nice yellowish belly and a perfect tail.
Recently, her belly has turned to have an olive-ish green color, the same as my other girl's belly. And her tail seems to have dried up, and not from shedding poorly. Any ideas of what it could be from?

They've had a pellet-type cat litter bedding, which is pine. I just read that that could be bad, so that's being changed. But this seemed to happen pretty quickly.

Thanks!!

TheBeansprout