Artheritis[HED?] + Going Grey?

[Scythe]

The Vet's office has much brighter lighting than my room, so I've only noticed now... But Roy(who was... well, once, a black hooded) has started going grey from behind his ears and down under his chin -- like a beard! And the occasional splotch on his head in the right angle. What I was wondering, is around what age do you normally see rats begin to 'go grey'? Roy is about 19 months old, but I've always suspected he was a little older.

Also, for a little while now, I've noticed he sits kind of funnier than the other two sit. the other two mostly sit with their feet flat on the ground underneath them while they hold something and eat, etc. Roy, on the other hand, sits... well, on his 'tail supports' with his feet stretched out in two directions almost like a V. When I mentioned this to the Vet, she thought maybe he's beginning to get artheritis? But I thought that would be kind of weird -- he gets around just fine, other than his head tilt, and certainly HASNT slowed down or given up getting into high places. But then I thought... maybe he sits like that so that he has better balance? Or maybe it's HED?

Ill try and see if I can get a picture of his 'greying' or his funny little way of sitting.

 

[DadRat]

He might be "rusting" some as he ages. Our black hooded boy is rusting redish in his hood.

And 1 of our 3 started showing HED symptoms around 20-21 months, but the other 2 haven't yet.

 

[Scythe]

Hmm... Isnt rusting usually the reddish orange tints, though? He's actually going like... full out grey! It's very noticeable in really good lighting.

So maybe it is possible he's a little bit older...

 

[jorats]

I've had some rats actually go grey. Grey/white hairs but they were closer to 30+ months.
But rats age at different speed some are old at a young age while others are young at an advanced age. My Loki looked and acting young up until she was passed 36 months and only showed her age at about 40
I've also had rats who looked very old at 24 months of age... but those were my first rats, those that were not fed a healthy diet so I had chalked it up to that but it could very well have been genetics.

 

[Scythe]

Yeah, that seems like what it was with Roy. Just out of nowhere... grey! I can sorta see it now at home since I know what I'm looking for, but before it just kinda seemed like he was shedding a lot(which he does! it's so weird, white fur EVERYWHERE). he doesnt act old, though, aside from his strange way of sitting. The second he's out of the cage he forgets how to walk and bounces everywhere.