Rat Coat Types

Coat Types I've Produced

This is not a comprehensive list of all rat coat types; just the ones that have been bred here at Paper Heart Rattery.


Black Variegated Male

Sable Burmese Male

Russian Blue Female

The typical rat coat - the hair is short, smooth and shiny. Males usually have longer "guard hairs" than females, especially as they age, and males' coats are usually coarser than females'.


Agouti rex at about 4 weeks old

Rex Baby Fur

Adult Cinnamon Rex

Rexes are curly-coated rats. Rexes can come in a wide range of "curliness." Some rats show little to no wave to their fur and others are very curly...some are harsh and some are very soft. Males will generally have curlier coats than females in the same litter. Baby rexes go a little bald at about 5-7 weeks old, when they grow their adult coats. I have varying qualities of rex in my rattery - I am working to improve this but it's a slow process to breed out the "bad" rex and breed in the "good!" Rex is dominant, so if a rex rat has a litter about half the litter should be rex.

Double Rex

4-5 week old double rex; same rat is pictured in both photos

Adult Russian Blue Double Rex

Double rex is when a rat gets two copies of the rex gene - one from each parent. They start to go bald at around 3-4 weeks old and after that they continue to shed their fur in very interesting patterns! Others will keep a fine coat of fuzz throughout their lives and sometimes double rexes are virtually indistinguishable from true hairless; it's always a surprise how they turn out! Sometimes these rats may be referred to as "patchwork" because they will have patches of fur in some spots and bald spots in others. I have double rexes very infrequently but always enjoy watching the changes they go through as they grow!


Cinnamon harley at about 10 days

Agouti harley at about 4 weeks

Adult cinnamon harley

Harley is still a fairly new variety. It is very cute! Harleys are essentially longhaired rats. Their hair is very soft and whispy. Harley is recessive, and since it came from one rat and is a recessive gene, the line was heavily inbred to keep this trait alive! Now the goal with harleys is to outcross to improve their size and type. It will be a slow process but they're well worth it! I would eventually like to bring harley into all of my lines, but this will take many generations!
As babies harley rats have very "greasy" looking fur. As they get a bit older the hair gets long and whispy. They seem to go a bit bald at about 6-8 weeks, simliar to rexes, and then grow back hair that's over an inch long.

I have put together a separate page with information and photos of harleys! Click here to go to that page!


2.5 Week Old Hairless Dumbo

Fawn Hairless Dumbo at 4 weeks

Adult Hairless Dumbo

Hairless rats develop a very fine coat of fur as babies; at about 3 weeks old this fur is lost almost completely. They may grow a few hairs here and there as they grow up, and their faces may have some peach fuzz on them, but soon they lose just about all of that! There are some health issues associated with hairless - they are more prone to eye problems since they have no eyelashes to keep their eyes clean, and they are more sensitive to cold than rats with fur. They need a little extra protein in their diets since their metabolisms are faster - their little bodies have to work harder to keep warm. There have been reports that their lifespans may be shorter than furred rats because of this, but I don't think that this has been confirmed. Their skin does tend to get scratched and develops blemishes (and occasionally cysts which require vet care) more easily. As always, keep an eye out for any signs of infection, but most of the time they heal without a problem.
Hairless females may have lactation problems; this appears to be genetic. Some hairless girls from my lines have been bred, and have had no problems nursing their litter.
Hairless is recessive, so both parents need to carry the gene. I do occasionally have hairless rats pop up. It is carried in two families of my rats. It is not something I have commonly, nor it is something I am intentionally breeding for at this time.