Like all the other colour genes in the genetic makeup of rabbits, they are difficult to understand. How they work and why they create the colours they do. Once you have grasped a basic understanding they should all become a lot clearer.
Steel genetics however seem to be more confusing than most for some, so here I shall try and give you a simple and easy to understand outline of what the steel gene is, how it works and the compatible colours to breed with Steels.
Es or the steel gene is a modifier gene which means it can only exists as an extension of other locus'. In order for the steel gene to work correctly it needs (A) or (at), Full Colour (C) and Full Extension (E) to be present. Although the gene it modifies is full extension (E) it needs those other genes (agouti pattern or tan pattern and full colour) to give the visualisation of the steel colour its full clarity.
A Steel is basically an Agouti with the modifier gene being expressed. If we look at the two rabbits genotypes next to each other you will see what I mean.
AABBCCDDEE This is an Agouti
AABBCCDDEsE This is a Steel
See how the only difference in the two genotypes above appears on the first full extension gene, thus making the agouti rabbit steel.
The steel gene works by darkening the banding and the light hair colour in the coat to leave only the tips of the coat colour visible, hence steels appear in essence to be a black rabbit with Gold Ticking. Genetically however they are not a BLACK rabbit and must be kept away from black or self breeding at all costs.
The best colour to use in your steel breeding program is AGOUTI as this is the base colour that the gene best modifies. If there were NO agouti's there would be no steels, so use them all you like and you will eventually breed something you are happy with the colour of... once you have this you can try and cement that colour in your line by breeding back into the animals that have bred you it in the first place..
The evenness or amount of steeling, whether it be heavily ticked or lightly ticked has nothing to do with using an agouti. It is down to the other unseen modifier genes which intensify or reduce the expression of the colour. These unseen modifiers are present in ALL rabbits and work in different ways with each different colour. It’s like when you get Sooty Fawns in 5 different shades in the one litter.....and none of them are the same shade as the parents... it’s the luck of the drawn, but correct colour can be bred for with selective breeding for your desired preference...
Steels are no different to any other colour and as with all other colours and how to breed them, there are, and always will be old fish wives tales of 'don't do this, do that' which have no logical explanation and are only thought to enhance or diminish colour quality.... but as I have previously mentioned, keep steels well away from Self’s especially Blacks and also from anything carrying OR expressing the non-extension gene (e)
Because Steel is the most dominant in the E series it CAN NOT be carried. There for once you introduce this into your lines it can be very hard to eradicate. By using self’s and the non-extension gene in your steel breeding, you are likely to lose track of the Steel gene altogether (but only visually). This is because it can be masked or hidden from view by other genes your rabbit may be carrying or expressing.
aaBBCCDDEsE - with the expression o f the self gene
AABBCCDDEse - and by the non-extension gene being carried
So if you have a rabbit that is expressing the self gene and the steel gene like this aaBBCCDDEsE it will be very difficult to tell if this is a Black rabbit (which looks like this aaBBCCDDEE) or is indeed a masked steel. The reason for this is as explained above.
The steel gene needs 3 locus genes to perform correctly and in the case of this masked steel, ONE of the series has been changed (to aa) thus removing the ability of the steel gene to show its self fully.
By the carrying of the non-extension gene in a rabbit expressing the steel modifier gene, one of the genes needed to show the steel off to its full advantage has also been changed. This would be the second extension gene on the E locus. If it changes from full extension E to a non-extension e then once again the modifier gene cannot perform correctly and its visual impact is lost. So a rabbit with the genotype AABBCCDDEse also looks black.
In both the examples above there may be some slight steel ticking somewhere on the rabbit, giving you an indication as to is true colour, but in some cases there is none and it will only become apparent when mated to a rabbit of colour which can be modified once again by the steel gene, like an agouti.
SUPER STEELS - EsEs
Now, Super Steels can be a bit of a nightmare also, if you are not breeding Steels; as a Super Steel is the most dominant of Steels. They are often mistaken for or catagorised as Self Steel, but this would be incorrect
As explained earlier in these genetics pages a rabbit takes on one colour gene in each series from each parent. If you mate two steels together you have a 25% chance of creating Super Steels. They will take on one Es from one parent and another Es from the other and will then become AABBCCDDEsEs.
50% of the litter would be Regular Steel EsE
25% of the litter would be Agouti EE
These rabbits are doubly dominant for steel and no matter what you mate them to, they will always pass it on. So if you mated a Super Steel to an Agouti you will get 100% steels in the litter, If you are breeding for Steels, this coloured animal will be of great help to you as he will guarantee more steels. If you aren’t wanting to breed steels he can be your biggest nightmare. Mating a regular Steel to an agouti will only give you a percentage of 50% Steel Babies, if you work on the law of averages.
As long as you follow the basic rules above regarding steel breeding you can't go far wrong. Deviate from them and you will never quite know just how wrong you have gone.