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`E` Series
The `E` Series is responsible for the extension of black pigment in the hair.
The order of dominance is as follows:-
Es = Super extension of black pigment as in steel coloured animals.
E = Normal extension of black as seen in agouti, black, blue and chinchilla etc.
ej = Japanese brindling as in harlequin and magpie coloured animals.
e = Non extension of black as in sooty fawn, orange, fawn and sealpoint etc.
As you can see from above, the extent of black pigment really affects the colour of your rabbit! If you take a normal black rabbit and compare it to a sooty fawn you will see that when the black pigment is not extended the yellow pigment has a field day!
The most recessive of the `E` series `ee` illustrates this the best.
Both the black and the sooty fawn rabbit have the exact same `A`, `B`, `C` and `D` genes but differ only in the `E` Series. Likewise, the agouti becomes an orange and the opal becomes a fawn when the dominant `E` is absent. Even more striking a contrast, the medium Siamese sable becomes a sealpoint, and in a black otter you will see the equivalent yellow animal looks very similar to the sooty, but on further inspection you will see it has a white belly and is, in fact a sooty-otter!
The recessive gene `ee` is not quite strong enough to remove every trace of black in the coat and this is best illustrated in the self patterned animals by the dark mask, flanks and points of the sooty fawn and sealpoint . The agouti patterned animals express this by retention of dark guard hairs on the flanks as in orange and fawn animals, this is more apparent in the first generation which came from an agouti coloured parent, but if you keep breeding orange to orange the dark hairs tend lessen with each generation.
I tend to call the recessive `ee` a yellow animal be it orange, fawn, beige, or sooty fawn just the same way as I call the recessive `dd` a blue animal if it is opal or blue etc, but if we get really technical beige and fawn coloured animals are both blue and yellow!
The gene `Es` is an over abundance of black and expresses itself in colouring the white belly of the agouti, in the steel the belly colour is black and the blue steel has a blue belly. The gene can only express itself properly when combines with the dominant `A` gene and you are left with a self coloured animal with steel ticking.
If the `Es` gene combines with the self pattern `aa` you can have a bit of a problem on your hands as the babies look pure black and some of them show absolutely no trace of the steel gene whatsoever throughout their lives until the day you breed it to your nicest agouti coloured animal and a whole bunch of steel looking animals with chestnut ticking evolve from your ( apparently) black babies. Steel babies are usually born black and the ticking seems to start appearing after the first baby coat has moulted. These animals might look like self patterned but they are in fact agouti patterned, but if they display the chestnut ticking they are not good coloured animals.
To prevent the ticking from being chestnut some people mix in chinchilla to turn the chestnut into steel but I would not like to comment on the good or bad points of this practice as I do all I can to breed out the steel gene if it gets into my litters. When I first started keeping rabbits I bought a lovely black buck and bred it to self coloured rabbits generation after generation. Four generations down the line I had showed one of the black bucks and did well in the self classes with him, one day I decided I wanted to breed him to an agouti doe and found out by the resulting litter that he had been hiding the `Es` gene and was in fact aaC-D-Ese as he had sooty fawn in the same litter. The doe was AaC-D-Ee and only he could be responsible for the steel turning up. I traced back and found it had come from that original `black` rabbit purchased over five years beforehand, so beware of mixing steel with black!
If you want to testmate any new blacks you have purchased, try mating them to orange because if the litter results in only agouti and black and no steel it will be safe to call it a black!
The `ej` gene is a strange one to study. I introduced this gene into the dwarf lop breed in 1988 and found that the type was very presentable by only the third generation, in 1990 my harlequin buck won best in show in the rare variety section at the Bradford Show at Doncaster and although there was no 5 star CC offered for unstandardised rabbits, at the end of the day it did not matter, I knew that all the work I had done with genetics to create the new colour gave me a real sense of achievement that day and nobody could ever take that away from me. I hope you get that feeling one day from creating your own colours with genetics. In January 1996 all colours of dwarf lops were accepted as standard, as long as a standard existed for that colour, and I was able to take another two new colours to the Bradford that year, a blue magpie and a squirrel, and put them in the main show in the A.O.C class. The squirrel came 6th and the blue magpie 8th in a class of 20. Another good day! Anyhow, I digress, back to genetics!
The harlequin gene acts as a mixture of two different genes, a bit like mosaic in other animals. Some patches or stripes look like they are influenced by the `ee` gene and others by the `Es` gene as you get an animal striped in orange and black with no white belly when combined with the agouti pattern `A`. No two animals have identical markings and the pattern is entirely random as some really well marked animals produce poorly marked offspring in one litter and excellently marked ones in another litter to the same partner! If you combine the harlequin pattern with the dark chinchilla gene you get a magpie which is black and white instead of orange and white, as the dark chinchilla gene removes the yellow from the coat. As usual you can produce blue versions of both the magpie and the harlequin, but to produce a correctly marked animal is quite difficult, just look at the standard for these in your breed standard book and you will find that the ideal markings are arranged on opposite sides of the body. For instance, with a blue magpie you are trying to achieve an animal with the correct type as a dwarf lop with one blue front leg and the other one white and then the back legs should be coloured diagonally opposite to the front ones, combine that with the face split down the middle, one side blue, the other white. One ear white, the other blue, need I go on? No-one said this was easy did they?
If you use a self patterned animal instead of an agouti you will find traces of the points and masking still apparent. The thing to avoid if you are breeding harlequins or magpies is using the `E` gene as harlequin gene can leave traces of itself if inherited recessively, in other words if you breed a harlequin to an agouti and you get an agouti patterned baby, look the baby over very carefully before you put it into a show as you might find little black patches where they should not be!
I have produced an agouti with half a black chin and the other half the normal white, another agouti had a small black patch on the inside of its back leg, This gene must be used with caution ! It would be much better to breed harlequin to harlequin, but if you want to improve the type or introduce some unrelated stock stick to yellow animals to breed the harlequin to.
The same goes for the magpie, use a frostie point instead of a chinchilla and all should be well!
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