Colour genetics anyone??

Spyda

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I have a homebred bright bay mare and have had her tested for the agouti gene. She Aa, so heterozygous agouti. Is it necessary for me to test her for red/black? I did back in 2008 but due to problems at the testing lab never got the results certificate. From what I remember she was carrying red, but not black (was ee) - but I can't 100% remember, to be fair.

I am planning to put this mare in foal next year and would like a guaranteed palomino or dun. I quite like McJonnas but he's not double dilute, so my question is - if my mare is NOT carrying the black gene (so is ee) would she still possibly throw a smokey black when put to a single dilute cremello stallion? Since I've not decided on the stallion yet, (sorry to sound pea-brained) but how would selecting a perlino stallion influence things?

Many thanks to anyone who can enlighten me.

PS: Any recommendations for a decent jumping cremello stallion to consider would also be appreciated too! Over 16.1 preferably and graded. :)
 
If your mare is bay, she cannot be ee. A bay horse is a black horse with the bay gene. ee is a chestnut horse - EE or Ee is a black horse.

You cannot guarantee a palomino from your horse. She could pass on the black gene - you could up her chances or producing a chestnut based horse by only using a sire with a chestnut base, ee.

Without knowing whether your mare is Ee or EE I cannot say if you could guarantee a buckskin (false dun). If she is Ee, you could not - she could pass on the chestnut. If she were EE you could, if you put her to a perlino which was AA for bay.

I think you may have your colour genetics a bit mixed up, if by McJonnas you mean the cremello warmblood. As a cremello, he is a double dilute, guaranteed to pass on one copy of cream. So on your mare, you'd get a chance of dilute black, buckskin (false dun) or palomino foal. If you don't want a dilute black foal, you must pick a stallion which is AA for bay.
 
For her to be bay, she has to have at least one copy of the extension gene, so cannot be 'ee' as that is chestnut.
The extension gene controls whether a horse is black-based or red-based. 'E' is dominant over 'e', so for a horse to be black-based they can be either 'EE' or 'Ee'. For a horse to be red-based (chestnut) they have to be 'ee'.

The agouti gene controls whether a black-based horse is black('a')/brown('At')/bay('A'). It does not have any affect on red-based horses.
For a horse to be black, they have to be 'aa', as both 'At' and 'A' are dominant over 'a'.
For a horse to be brown, they are either 'Ata' or 'AtAt', as 'A' is dominant over 'At'.
For a horse to be bay, they just have to have one copy of 'A', what else they carry only matters in what they can produce.
So for your mare to be bay, she has to have at least one copy of extension, if you remember she's carrying red, then it's likely she's 'Ee'. But she could be 'EE' which means she'll never have a red-based foal (chestnut, palomino if bred to a dilute)

Depending on what the sire's agouti genes are, she could produce a smokey black when bred to a cremello stallion IF your mare passes on her 'E' if she is 'Ee'. A single dilute cremello stallion is a palomino, so you'd only have 50% chance of producing a dilute, and again, depending on the sire's agouti genes, could produce a smokey black.
While a perlino is a bay horse with two cream genes, you can't tell unless you test if they are carrying an 'e' or if they are homozygous for 'A', so you could still get a smokey black foal.

ETA: Whoops, just repeated what varkie said, should of checked no one replied while I was typing!
 
Brilliant, thanks. I remember she IS a red carrier and Ee.

Yes, must admit my colour genetics is still very basic. I do know that I've seen cremello stallions which are guaranteed to throw palomino or dun/buckskin (but no smokey blacks) when put to any solid coloured mare. I know McJonnas isn't one of these though.

Quote: Without knowing whether your mare is Ee or EE I cannot say if you could guarantee a buckskin (false dun). If she is Ee, you could not - she could pass on the chestnut. If she were EE you could, if you put her to a perlino which was AA for bay.

So, if she IS Ee then she could produce buckskin (if black is passed on from dam) or palomino if the red is passed? Is that right? And if she had been EE then she would have been guaranteed to produce a buckskin and nothing else colourwise?
 
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I can't comment on the genetics, I leave that to the experts on here.

I get my statistics from Color Calculator which is only a guide, and I never bother with all the factors because I am not fanatically breeding for yellow, I'd have dilute mares if I was, I am happy if the foal comes out alive and kicking, bonus if it is yellow, but not essential.

Bay to palomino:
29.17% - Buckskin
29.17% - Bay
16.67% - Palomino
16.67% - Chestnut
4.17% - Smoky Black
4.17% - Black


I have had two bay mares produce palominos to palominos.
This is a Morgan/Standardbred (Standardbreds do not come in dilute, Morgans can):
7735bca5.jpg


The other is a bay arabian, she was in foal when I bought her and had a palomino, then for me had two chestnuts and a bay by a different palomino.
 
Any cremello stallion (and this includes McJonnas) is guaranteed to pass on one copy of red and one copy of cream. What colour foal will result then depends on what colour mare he is put to. You could only guarantee a palomino by putting him to a chestnut mare. You could only guarantee getting a buckskin by putting him to a mare which is homozygous for both black and bay.

If your mare is Ee and Aa, then by putting her to any cremello stallion, you have foal colour possibilities of Smokey Black, Buckskin or Palomino. With her colour genetics, put to a cremello, you cannot guarantee not getting a smokey black, unless you found a cremello who was also homozygous for bay (I am not aware of one out there). If you don't want a smokey black, you'd do better to put her to a perlino, who is homozygous for bay, which will eliminate the smokey black possibility.

If your mare had been EE and Aa, then put to a cremello stallion, she'd still be able to produce a smokey black and a buckskin, but not a palomino. She would have had to have been Ee and AA to produce either a buckskin or a palomino but not a smokey black, and EE and AA to produce a buckskin only.
 
Any cremello stallion (and this includes McJonnas) is guaranteed to pass on one copy of red and one copy of cream. What colour foal will result then depends on what colour mare he is put to. You could only guarantee a palomino by putting him to a chestnut mare. You could only guarantee getting a buckskin by putting him to a mare which is homozygous for both black and bay.

If your mare is Ee and Aa, then by putting her to any cremello stallion, you have foal colour possibilities of Smokey Black, Buckskin or Palomino. With her colour genetics, put to a cremello, you cannot guarantee not getting a smokey black, unless you found a cremello who was also homozygous for bay (I am not aware of one out there). If you don't want a smokey black, you'd do better to put her to a perlino, who is homozygous for bay, which will eliminate the smokey black possibility.

If your mare had been EE and Aa, then put to a cremello stallion, she'd still be able to produce a smokey black and a buckskin, but not a palomino. She would have had to have been Ee and AA to produce either a buckskin or a palomino but not a smokey black, and EE and AA to produce a buckskin only.

Thing is I get confused by stallion ads like http://www.stallionsonline.co.uk/stallion_41395.html where they say that a bay mare will produce 100% buckskin - or buckskin or palomino if the mare carries the hidden red gene (like mine does). I've seen several others which also state foals from ANY solid coloured mare will be either palomino or buckskin with no chance of smokey black.
 
Paul Wyatt at Ranby hall Stud has a perlino - Perlino Krinsky. He's incredibly knowledgeable about breeding - Paul, not the stallion - and when I met him was happy to chat for ages about breeding, colour and anything else. You could talk to him, but phone rather than email, because he doesn't often check. He is cutting down a lot, so might try to sell you a horse! Google Ranby Hall stud
 

I don't know if they do AI out of North America, ask her, she is on here, True Colours.

There is a cremello tb in the UK with very similar breeding to GG, actually I am pretty sure he belongs to an HHO member, I know her RL name but not her HHO name. I am sure someone will, perhaps the lady herself.
 
Thing is I get confused by stallion ads like http://www.stallionsonline.co.uk/stallion_41395.html where they say that a bay mare will produce 100% buckskin - or buckskin or palomino if the mare carries the hidden red gene (like mine does). I've seen several others which also state foals from ANY solid coloured mare will be either palomino or buckskin with no chance of smokey black.

The stallion has been tested to be AA - 'A' is responsible for making a black based horse bay, and as he has two copies of it, he will always pass it on and as it's dominant over the other agouti alleles, it doesn't matter what the mare passes on.
If the mare passes on an 'E', the foal will always be buckskin. The stallion can't produce buckskins by himself, because he doesn't have an 'E'. If you bred to this stallion, you'd have a 50/50 shot of palomino or buckskin.

What stallions owners are saying is that they have tested to see what agouti alleles their stallion has, and he doesn't have an 'a'. To have a black horse it has to be 'aa' and as the stallion doesn't have an 'a' to pass on, he cannot produce a (smokey) black.
 
I don't know if they do AI out of North America, ask her, she is on here, True Colours.

There is a cremello tb in the UK with very similar breeding to GG, actually I am pretty sure he belongs to an HHO member, I know her RL name but not her HHO name. I am sure someone will, perhaps the lady herself.

Is it Electrum you're thinking of? Yes, he's very nice although I was veering away from TB as my mare is WBxTB and I'm wanting to try for something with a little more bone than the dam. Still, he IS very nice. I am tempted. I like Cruiselines stallion too - although there's a huge risk of not getting buckskin or palomino to him - but who cares????! He's lush and so talented already. *Drooool*

I know I shouldn't just try for colour but this is going to be my last foal for myself and it would be nice to have a bit of extra colour as well as the talent to be able to pop a decent size fence. I used to show palominos so have a bit of a particular liking for those if I'm completely honest :D
 
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