Hey. I've only got 4 retired breeders now here. I did have some rats with the thin white blaze on the face. They all seemed to grow well, although I never bred FOR them. I did use a male with a thin blaze face as a stud, and he threw a lot of blaze face babies, and they all seemed to do quite well.
Also, I had two hairless rats(the typical "hairless", not whatever rare breed only found in labs that no one was talking about "Hairless") that were great moms. I never did have them produce hairless babies, since I never bothered to get a hairless carrier male to use as a stud. But they threw litters of 8-12, usually with those thin terrible looking coats, and nursed them fine. One lived to be 3 years old in fact, one of my oldest breeding females, although she did not have as many litters. I really like hairless, cause they're so cute and warm.
I never have had any luck with blue rats. No matter what, every blue manages to die. So I gave it up. I have had several dumbos, but I don't care for the look, so I never tried to breed for it. Tons of hooded of all colors.
Right now I have one male retiree, he's a dumbo with a soft brown coloration. I don't know colors on rats, so he's just "soft brown" and not anything special, but he's cool. The other three retirees are all white red-eyed rats. One has the thin coat, she might be a half-hairless one.
I bred for feeders, but I liked keeping the most interesting ones for breeders(as long as they produced). I also tried to treat them as cherished pets, as far as their conditions. Lots of toys, chew things, treats, good food, and fresh bedding constantly.
I've since been told that my temps here might just be too high to do very welll breeding rats. I might try breeding my own at some point, but right now, I don't have time to take care of 50 adult breeding females plus assorted male studs, and raising young to feeder size. No time.
I love rats as pets, highly entertaining and clean pets.