Rat Breeding Articles

Breeding Self Rats

© Lisa Irvine

Edited April 2011: Please note that Black-eyed white is no longer a recognised showable variety at NFRS shows.

I think that the only self variety that has not been born a Halcyon rat would be one of the 'new' ones - the Russian variety. I do wonder why there are not more people breeding selfs. There are fewer common denominators to get right. Recently I've heard a couple of people state a desire to breed a nice rexed roan dumbo kitten! Are you mad? Firstly and most importantly you need to breed a rat with nice type, size, good head and eye etc. Then as a roan you need to worry about its markings, its depth of colour and its roaning and then as a rex it needs to be nicely curled with no bald patches AND then you have to worry about the shape of its ears. Talk about making life hard for yourself!

I haven't judged much in 2004, but have been to quite a few shows and apart from the aforementioned Russian varieties the self representatives on the show bench have been low in numbers and of a generally poor quality. There is only one 2004 self that sticks in my mind that showed the true class that a self rat should have - the buff self doe that belongs to Serendipity Stud. Sitting here writing this it is ironic that this champion animal should be one of the rarest selfs around, there should be blacks, blues, chams, chocs, pink-eyed whites etc around of similar quality!

When there are more than two exhibitors concentrating on one particular variety then the quality produced naturally increases. You have to breed a better rat with which to beat your competitor. Apart from Russian varieties & British Blue & Lilac rats I personally cannot name a self variety that currently has duplicate breeders.

Pink Eyed Selfs

We still only have 2 standardised pink-eyed self varieties, pink-eyed white and champagne. It has been a long time since I can remember anyone successfully breeding lines of show winning pink-eyed selfs. I am guessing that these are purely a fancier's variety & specifically a fancier who likes cleaning out!

I say this because most people I have spoken to prefer dark-eyed rats and also find it easier to sell dark-eyed rats. These two varieties also need to be kept immensely clean. I know from breeding buff selfs for a long time that the only way to keep these pale varieties spotless for showing, but also glossy and full of coat condition is not to clean or bath them, but to not allow them any opportunity to get dirty by keeping their living arrangements as clean as you possibly can.

In the long run this kind of living arrangement is not good for the health of the rat. They will scent mark more, urinate more & end up with kidney problems. Rats like their environment to smell of rat, it helps with their social structures, hierarchy, confidence and security.

I used to just keep my specific show rats in the ultra-clean environment and resigned myself to the fact that once grubby, they pretty much stayed that way and often then had to retire. Lots of stain remover and bathing can help, but they do lose coat condition and gain coarse dry coats instead.

Pink-eyed white

The best place to obtain a new stock of pink-eyed white rats is still from laboratory stock. They are likely to carry marked gene also so bear this in mind if you do set off to get some and them mate them together, you may end up with some surprise hoodeds extra!

Breeding pink-eyed whites in itself must be the easiest variety, surely? I have already bemoaned the fact that they must be kept clean, but apart from that all that needs to be worried about is type, size and shape. No worries about depth of colour, markings, ticking etc. Just size and type.

If you do find yourself the lucky owner of a pair of pink-eyed whites or a have a doe and manage to find her a pink-eyed white husband. I would recommend selecting the best buck in the litter and the best two does. When old enough mate the buck to both his sisters, and assuming that both does supply you with nice pink-eyed white kittens and not a complete mish mash of different varieties then again select the best buck and two does from these 2 litters and start your line of pink-eyed white rats from here.

I have seen a stunning young pure white doe on the show bench, her coat sparkled like fresh snow and her huge eyes looked like pale pink rose quartz gems on her classically shaped head. Even as one of those people who openly admit to preferring dark-eyed rats that little doe was a real stunner & has truly stuck in my memory.


Due to the fact that the champagne rat has been really poorly exhibited in the last few years I am guessing that some newly appointed judges will struggle to identify a really classic champagne coat colour.

It is so difficult to train new judges on each variety represented within our show schedule at present as so few of our standardised varieties are actually being specifically line bred or selected for by breeders. Champagne unfortunately is now one of these.

I must first make the point that I have accepted that most people do see colour slightly different to the person standing next to them, however, each self rat does have a colour standard written down for it and this is the colour that breeders must select for and judges must award prizes for.

The champagne rat should be a pleasing delicate shade of beige as the name suggests, you would not expect any animal called champagne to be a dark, greyish, muddy mid browny colour, but a light, bright warm shade. It should not be yellowish or greyish or brownish - it should be what it is - champagne. Champagnes can also be too pale. As with any self, it should recognisably be what it claims to be and not easily confused with any other colour variety. The eye should again be a pleasing pale pink. This rat, a pink-eyed self is probably genetically a pink-eyed chocolate. My self chocolates were never crossed with pink-eyed rats as I used to breed them with buffs. But I have had champagnes born from black kittens, which were too dark and grey in colour and others born from mink who were far too pale & patchy for the show bench.

Champagnes also suffer from silvering in the coat, especially the bucks. Many think that you can get away with silvering in a pale self variety and it is true that you can get away with a small degree of it without it noticing much. If the silvering on a champagne is very apparent then it is likely that he is far too dark in colour anyway.

Also look out for white spots under and white feet, it is amazing how these go unnoticed. I once had a champagne doe that gained a total of 5 stars in her show career. Only the top judges noticed her white belly spot.

Champagnes are really a variety that need concentrating on solely, rather than one you can mix and match successfully with other varieties although some beautiful champagnes do just 'fall out' of lines that carry pink-eye. Recently I have seen some nice ones produced in British blue litters.

I have found it a real shame that within the last year most shows have had no pink-eyed self entries, and when they have they have been one or two rats and rats of poor quality. What can we do to encourage a few breeders to take up the mantle of the pink-eyed self rat?

If you ever find yourself considering a new direction within rat-breeding, give the pink-eyed guys a thought. Contact either myself or breeders@nfrs.org, I'm sure that with the help of all other ratty breeders out there breedable rats could be found? Couldn't they?

Black Eyed Selfs

The rest of the selfs are generally Black-Eyed, except the other New Variety colours, Quicksilver, Havana & Powder Blue. Black-Eyed White, "creamy tinge or staining. Any coloured hairs to be severely penalised. Eyes black".

The true Black-Eyed White rat is really a rat in disguise. He is really a marked rat! The Black-Eyed White has been developed by breeding rats with markings on their heads/faces selectively so that there are no markings left, except where the marked pigment affects the eye colour. Understandably much selection and in-breeding is required to create this variety.

So, taking on this variety is not for the faint hearted. As with breeding any marked rat, there will be only very few, if any, kittens in the litter that will be in any way marked in the way you would have liked. This leads to decisions having to be made about whether litter size is reduced or if all these surplus kittens can be re-homed.

Selective in-breeding can also 'fix' problems into lines, as well as desired traits. The Black-Eyed White is an incredibly difficult variety, as well as the selection for 'un-marked' kittens, selection must be made for type, size, temperament and health.

To breed this variety you need to start off with some Black-Eyed Whites if at all possible. If not, then you need to source some marked rats, probably under-marked Capped, with the best type that you can possibly find & then breed the least marked rats to the least marked offspring.

Try not to select offspring with markings in exactly the same place (for example over the left eye) as you could 'fix' this marking into the line & find it very hard to eradicate.

Traditionally it has always been difficult, but not impossible, to consistently breed a line of well marked rats that also have excellent type and size. The breeder who gains the good markings on big kittens is a lucky one.

Black-Eyed White rats also commonly suffer from deafness, the lack of pigment cells causes an inner ear deafness, other health problems can also be associated with this variety, but are less common, these include Epilepsy.

The Black-Eyed White must not be confused with the colour Ivory. The standard for Ivory is as follows:

'Body colour to be very pale creamy white all over with no odd coloured hairs or patches. Ears and tail to be pink. Eyes Black'

The difference in the two standards is very slight but the genetics for the two varieties could not be more different. The genetics for a true Black Eyed White are: P hehe, the genetics for the Ivory are still being worked on but are thought to be Pink Eyed White with a dose of the Black-Eyed Himalayan gene.

The NFRS will trust breeders to show each variety in its correct class.

British Blue

'To be a deep steel blue without any brown colouration. Colour to be even with the belly colour matching the top. The colour of the fur when parted to be blue grey down to the skin'

The British Blue was first discovered in a pet shop in London in the summer of 1990. Strangely a Blue kitten was also discovered in a pet shop in California, USA in the summer of the same year!!

The British Blue was always known just as 'Blue' from this time until last year, when the NFRS decided to re-classify it as 'British' Blue last year in order for it to be more easily distinguished from the Russian Blue. Personally last year I was breeding British Blues and had many enquiries for Blue kittens that turned out to be people asking for Russian Blue, adding the 'British' on the front was really for administration purposes and to clarify things.

The first British Blue kittens bred in the UK had all kinds of health problems, the main one being a problem with a type of Haemophilia. One of the first bucks I owned would bleed frequently from his nail beds & later bled to death after being bitten by a cage mate. This problem gradually eased with successive outcrossing and in the late '90s the only remaining problem was that does frequently haemorrhaged when giving birth.

Throughout 2003/2004 I personally bred British Blues, Blue Agoutis, Lilacs and Lilac Agoutis and can honestly say that the British Blues existing in the UK today seem to have no such problems. Breeders were always advised to breed from British Blue does early and only once, but I never had any problems with does losing any more blood than normal when birthing at any age and the amount of litters had no effect either. This could only be the line that I bred, my line originated from one buck and was outcrossed by myself & then successively in-bred again to create British Blues, other unrelated British Blues in the UK or other countries 'may' still have bleeding problems, but if they do, by the time of writing I haven't been made aware of them, and would guess that the health problems have been successfully bred out (fingers crossed)!

Another problem that British Blue did seem to suffer from was weedy type and a tendency to 'plain' heads, again this problem does seem to have been solved and the British Blues out there now can be as good or bad as any other variety but the true coat colour as described in the variety standard does seem to have suffered from the continuous outcrossing.

The British Blue has been outcrossed to all kinds of weird and wonderful colours throughout the years. The standard asks for a deep steel blue, but most British Blues that I have seen around in recent years have been a much brighter colour than this, even my own. I remember judging early examples of Blue rats and describing their coat colour as like wet Lakeland slate.

To successfully breed British Blue it is best to keep a line of British Blue rats and cross them with Blacks. Select the deepest, blackest, darkest Blacks that you can possibly find, with as little silvering as possible. I wouldn't worry if the best Black outcross is a Berkshire or a self with white feet. I have found it easier to breed out the white spotting gene than to select against silvering. My outcross for the last Halcyon British Blue rats was an over marked Black Capped, it only took two generations of in-breeding to get back to selfs.

A bi-product of this course of action should mean that you also produce Black selfs that should be suitable for showing also, as you will automatically select for the same qualities in each variety: depth of colour and lack of silvering.

Once you have your foundation rats and start breeding it is basically a process of selection, from each litter select the darkest kittens, with the least silvering, best type and most even colouring - the Blue colour should be consistent from the root to the tip of the hair, any kittens with a paler base colour to their coat (Powder Blue) should not be bred from if it can be helped.

The biggest colour problem/fault with British Blue rats is 'rusting'. This is where large patches of the coat turn a browny colour, this always happens with age & I have found it more common in does than in bucks, but this may just be my line. This is another thing that can be selected against, once your does get to optimum breeding age, try to breed from the doe that has the least moulty and rusty patches in its coat.

Confusion with Russian Blue must be avoided, this should be relatively easy as a Russian Blue rat should be quite obviously heathered and a British Blue rat is not.


I bred self-chocolates consistently from the early 1990s until around 2003. I still think they are lovely and a good one is stunning and am often lured back to the temptation of chocolate.

I have been told that before Fiona Barker discovered a Mosaic rat in an Ipswich pet shop, subsequently bred from it and it produced a chocolate buck kitten that no real chocolate rats had really been concentrated on or exhibited seriously before as the majority of them had been rusty or bad self blacks. Breakfast - who was a black mismarked Berkshire and Hagar the choccy boy, Fiona please correct me if I am wrong, they dined from Clay the Rottweiler's dish and between them started a love affair with chocolate rats, that for Fiona is still going strong! Their offspring produced both the Adelphe & Halcyon chocolate lines and I'm sure most of the chocolate rats around now can be traced directly back to those boys.

The standard for Chocolate Self is as follows:

To be a deep, rich chocolate, as even as possible, devoid of any dinginess and white hairs or patches. Foot colour to match top. Eyes black.

Its genetics are: aabb or aaBBRr or aabbRr

When breeding any colour self, or most rats to be honest you will realise eventually that people perceive colour differently and that the description of a variety colour can be taken in many different ways by different people. Never more so with the chocolate rat.

The chocolate rat, whether he or she is self or not will be prone to patchiness of colour. It seems the gene that creates this colour works this way; it is very like the mink gene though perhaps a little more stable. The first chocolate rats displayed a fine array of shades of brown and also tended to rust towards the rump after the age of 8 months or so.

To successfully breed chocolate selfs it is all a matter of selection. As well as selecting for type size and health etc it is also a case of selecting to breed from the rats what have the least patchiness of coat, do not rust so early and also are the correct shade.

As stated already it is incredibly difficult to describe colour, however it was always taught to me and this is the rule of thumb that I used: chocolate rats are 'Cadbury' in colour. NOT Galaxy, NOR Bourneville - Cadbury is the shade you aim for!! A rich even warm chocolate colour is what needs to be aimed for and if you are in doubt as to whether the rat a black or a chocolate, then it is neither... a mink or a chocolate... again, neither.

Self blacks, chocolates and minks come in many varying shades, this will depend on many factors within their genetic make up and which colours their parents were.

A true chocolate rat is unmistakeably chocolate, it is the colour you would expect a chocolate Labrador to be or a 'lovely' pair of chocolate coloured crushed velvet curtains.

The other complete pain when breeding self-chocolates is white on the feet and silvering. This is another fault that needs to be selected against, or even for if you decide to breed silvered chocolates instead. I always found that silvering runs in a line. I was told that crossing a chocolate rat with any agouti based rat would make my chocolates more silvered, but I actually found that not to be the case - all it did do was introduce the occurrence of chocolate agouti into my agouti line. I actually put the success of my chocolate line down to the outcross I did with a Rivendell agouti buck, they were much better after that.

Self-rats will silver as kittens anyway (in fact all rats do) and chocolate and mink selfs more so than others. It is best to evaluate the colour of your chocolate kittens at 5 - 7 weeks of age. When they hit the next moult your sleek chocolate baby will suddenly become heavily silvered and a shade darker. This silvering will reduce, in most does it can almost disappear, in bucks it will be more prevalent and will not go away until he is about 16 - 18 months of age. Again, select against the most silvered, unless of course silvering is your desired result.

Selecting against white feet is also very good, but I found that white toes or one white foot could stay in the line despite repeated selecting against it and pop up almost randomly (always on the best baby in the litter!).

Your ratties will also almost certainly change colour throughout their lives. A kitten sold as being too pale often ended up on the show bench almost unrecognisable as the same creature and was praised for its good colour. This is something that only experience will bring, it is impossible to keep every baby to ascertain its colour at 6 months, but with any rats you may be debating on it may be wise to home them with a supportive person who will allow you to borrow them back to breed from or to have a kitten back from a litter they have bred.

When I bred chocolate I bred them in conjunction with buff self. I personally found that they complimented each other. I would imagine that chocolate and champagne could too as in both champagne and buff you are looking to breed an example of the variety that is neither too pale nor too dark.

If you have self chocolate rats and find that the offspring they produce is too dark or too light then you need to do a combination of things to change the coat shade, firstly again selection is the key, selecting the lightest, darkest, most correct shade in the litter is always the best choice to make, if however, your rats are not producing anything much darker or lighter then it may be worth introducing some dominant or recessive genes into the mix to try and subject a change to your chocolate line.

Introducing another colour outcross will not create instant results. Chocolates that consistently breed pale for example will need to be outcrossed to a very dark black or a dark British blue. Both of these could create a darkening effect, eventually. However on first mating with either colour you are likely to create a litter completely of black kittens. This is due to these darker colours being more dominant.

Your line will now also carry these colours, so a brother x sister mating or son x mother mating to try to get some chocolate kittens is the next course of action. However, depending on the purity of your line and the rats that you used to outcross you could be faced with a rainbow of self-babies and the chance of still no chocolate rats! Outcrossing takes bravery at times, but is great fun due to the excitement waiting to see what colour babies you have in your litter, it can also be very very disheartening when you seem to lose the colour you were working on altogether, so it may be wise to continue breeding your original line at the same time with other rats while the outcrossing is tried out! It is also worth remembering that a chocolate version of British blue (sometimes known as a Lavender) is not desirable.

It is always better to show chocolate does as selfs, they silver much less, have shorter coats and seem to have a richer colour. Bucks show better as silvered as they have much much more silvering and they don't get so patchy or rusty.

The main problems with chocolate rats seem to be with obesity, most of mine got fat, whether they were bucks or does. They were slow to mature, but could reach enormous proportions after the age of a year. The line of chocolates I had also had a higher than normal occurrence of small, near end tail-kinks. It is likely that chocolates 'out-there' in the UK that have not been imported are all related to Halcyon or Adelphe chocolate rats somewhere down the line, so tail kinks should be watched for.



To be a deep solid black, devoid of dinginess and white hairs or patches. Base fur to be black. Foot colour to match top. Eyes black.
Genetics: aa

Oh I remember when we despaired over the black self rat. They were all a bit browny and very silvered. No one really specialised in Black rats because they just weren't that nice and nice ones were extremely rare and very unstable - in as such that their colour never stayed. They may have been better prior to my start in the rat fancy, but my memory of the first exhibition ones I saw were that they were all a bit...well...brown.

Then all of a sudden from outer space arrived the British Blue rat and crossed with black produced a black of greater colour density. I remember the first time I saw a black kitten bred from British Blue lines exhibited at a show, it was owned and bred by Helena Prendiville and exhibited at a Surbiton show in the hall at Balaclava Road, (I do not remember the year, I am useless with remembering how long ago anything was, in fact I am useless at remembering anything!). This black kitten won Best in Show I think and we were all amazed at how black it was and thrilled with the prospect.

Following on from this more successful black lines were produced and many black champions and champ show winners have been produced.

The trick to breeding blacks is again very similar to breeding chocolate. Selection is the key. I was extremely lucky, I crossed a black capped buck to a couple of my chocolate does hoping to produce chocolate or British blue Berkshires and in fact I was presented with black Irish and self which had a very dark intense colour and hardly any silvering, they also did not tend to rust very early if at all and not being one to look a gift horse in the mouth I bred these black rats (in conjunction with Estelle at Alpha Centauri) and made up two champions in recent years.

Alpha Centauri Stud is now continuing these blacks inadvertently as wisely she breeds British blue and black together, both colours keep each other dark, intense and lessens the chance of rust and patchiness.

Nowadays blacks are of such good quality it should be fairly easy to maintain a stud of pure black rats and just use selection to keep down the level of silvering, patchiness and rust. Black rats these days seem to have really good type, it is unusual to see one with poor type and are popular with breeders who need a black outcross. It certainly would be beneficial if there were a 'pure' black line out there, which to my knowledge there isn't. All black rats in my shed and belonging to other breeders that I know carry many recessives and are liable to throw many colours. Luckily blacks seem to be much more stable than chocs and minks and do not go quite so patchy, I have seen patchy ones, but most stay relatively level, apart from the rusty bum, which does do tend to produce after their first birthday. They silver less and have shorter coats. If you find you have a line of very silvered blacks, then this can be selected for and shown in the silvered class. It is a long time since there was a stud specifically breeding for the silvered classes. Bucks always show better as silvered rats and sadly at most shows now the silvered rosette is won by a heavily silvered buck kitten of around 10 weeks old, who no doubt will have no silvering by the time he is 8 months old and was bred to produce show winning self does.

Faults to watch for on black rats are, as mentioned, silvering and rust, and also white on the feet. As I mentioned with chocolate rats, it is extremely hard to breed out white on the feet and toes, and relentlessly selecting against it doesn't seem to make a lot of difference. I have recently had a litter of black kittens, the marked rat in the line is now around 9 generations back and all successive rats in the pedigree are completely self - yet I have an Irish kitten in the litter. Some judges are notoriously hard on rats that have white toes, in this case it is sometimes better to select the judge you show under rather than the rat you show. It is true that the standard suggests a jet black rat with jet black belly and jet black feet & indeed if you look at a black mouse (on which I bet the standard was based) then you see a completely jet black animal - black to the end of its nails! Black rats are improving but not quite so good as that & I doubt they ever will be, but aiming to be as close as you can be is the key.

My black rats were and are also very large, I don't think that this is a general rule of thumb, just my line and as such matured very early and I found it very difficult to get the does pregnant, hence one of the reasons why my line has kind of floundered.

Watch out for white hairs spoiling a 'level top'. I have been known to spend the night before a show patiently with a pair of tweezers coaxing out those two white hairs that glaringly shone out from the rat's shoulders. Also pale circles around the eyes, this can be caused by a copper deficiency and I think I've seen this more apparent in blacks than any other variety. Feeding copper rich foods or dog food and dog biscuits clears this up quite quickly.

A last tip for anyone breeding and showing black rats. Keep them in as dark an environment as you can without causing their life enrichment to suffer, keeping them in a bright, well lit room will mean they rust more. And feed them seaweed powder as this increases the pigmentation in the coat and helps keep them dark.