Weird Black Patches On Hind Legs

[Lacre]

Papa Chops and one of the twins has developed a little black circle patch on their back right legs. It's so weird. I've checked them with a fine tooth comb if you know what I mean and I don't see any wound looking things or mites, but Chops has been a little over groomy with all of them. He has been that way since they were born. I don't know if any of you remember all my posts a few months ago about Petco selling me a girl that was in the boy tank (jerks) and of course Chops being the cage mate and being a boy got her quite pregnant. They had two girls and three boys, and of course he raised the males after they were done nursing with no problems. He absolutely loves his sons to death, lol. I was wondering if it could be from over grooming or something. I've been through all the allergy stuff and they have been fine on Carefresh all their little six month lives. It doesn't really look like loss of hair. You can't see any skin or anything. Chops is an Agouti and the little twin is a Spotted Agouti so the black patch is very obvious. Any ideas??

[volans]

one of my agoutis suddenly grew a load of black patches on her hind legs too. its in her actual fur colouring, so it must be normal..or an effect of hormones or whatever. i'm pretty sure there's no reason to worry.

[Lacre]

That's really weird. Both of my males have developed this on one back leg. They didn't seem hurt, and like I said there were no wounds or missing hair. So, I'm not really worrie about. It looks just like you said right in the fur like the rest of it just a little black patch. Thanks! I was so worried no one was going to reply.