My gerbil is just over 2 years old. He lives with one other gerbil, the same age. The other gerbil hasn't had any issues, however, this one has. His nails have some sort of fungus or something attached to it, and it's hard. His nails were bloody a couple days ago, however now they look like this and I'm worried they're infected. Someone please help, I just need to know what's going on. He's been getting skinnier and skinnier over the past month and has trouble eating and drinking.