Chocolate Dun - genetics please

[ambatt]

Chev - Had an interesting chat with another colour nut. She has bred two chocolate duns by a bay stallion from a liver chestnut and a chestnut mare.

What are the genetics of chocolate dun, if indeed there is a definitive choc. dun colour. Could it be the 'interesting' affect of liver chestnut??

Or is Chocolate dun seal bay?

[chev]

I've seen it used to describe a few colours, some of which were plainly not dun (!) but usually black dun or grullo. Neither black dun nor grullo are common terms here.

You could get a black based foal from bay x chestnut. You can't get a dun from those combinations though - unless, as I theorised on another forum ;) dun is the result of a complex of genes and/or and incomplete dominant gene rather than a simple dominant. And it still raises the question of what exactly a liver chestnut is...

What makes her class them as chocolate dun? Do they have true eel stripes, masks, zebra markings and dilution? Or are they examples like the mushroom Shetlands; red based but very dun-dilute looking in colour?

And Spanish bred too.... this gets more interesting by the day!

[ambatt]

Chev - I think the filly looks like Nott, smokey black, as the filly is in her foal coat it is difficult to tell, but I shall go and take photos!:D

The sire is 3/4 PRE the other being TB, the dam is liver chestnut PRE.

To me the sire Espiritu looks to have the smutty gene and be a seal bay like my Arab mare. (Bay sire, black dam).

http://i13.photobucket.com/albums/a299/ambatt/Espiritu.jpg

The filly:

http://i13.photobucket.com/albums/a299/ambatt/AztecSombria.jpg

Espiritu has sired two of these chocolate duns, but I am not sure what chocolate dun is, the nearest I can think of is that strange brown colour some Exmoors come in, and I am sure that is called dun.

[Gill]

Our chocolate dun resulted from our golden dun mare x bay stallion. The chocolate dun was a golden in reverse with golden hairs showing through on the nose, flanks, legs.

[chev]

Hmm... Espiritu is not showing any dun characteristics, and I'm assuming the mare doesn't either. So this filly is not dun, chocolate or otherwise; if neither parent has dun to pass on, she cannot be dun!

I think she is either brown or as you say a smutty bay like dad. Her legs look black which would rule out the darker shades of liver chestnut and I think her mane and tail will likely shed out black as she loses her foal coat. The other possibility is a dark liver chestnut.... time will tell as she sheds out on that one.

Dun (http://www.mustangs4us.com/Horse%20Colors/dun.htm) is explained nicely here (although chocolate dun is not a term used in the US particularly, just like grullo isn't used much here).

Colour aside though - what a filly! :D I like this one a lot....

[ambatt]

The only way I can think of this filly being a 'chocolate dun' is if the dam has the dun gene in her ancestry, being a Spanish lady.

I saw from the weblink that grullo is the effect of the sooty modifier, which makes sense I suppose.

I will go and see this filly and also her parents and see if she has any dun markings, eel stripe, barring etc. Anything else I should look for?

The filly is just a little light in the cannon bone and fetlock joints for me, but I wonder if that is her 1/8 TB?

She looks like one of your Welshies Chev!

This is not one I am lookin at to buy, I have set my heart on a boy, because I only ever have girls!

[chev]

She does actually look a lot like Blod - maybe that's why I like her... :D

To be dun she would have to have at least one dun parent, an eel stripe and dilute body colour. But she could have dun factor markings and not an eel stripe or dilute colour; dun is an odd one in that respect. Lots of horses do have 'primitive markings' (dun factor markings) without actually carrying the Dun gene - that would include leg barring, cobwebby stripes on her face or ears, pale hair in her ears (again - difficult when so many horses do have that characteristic anyway to say whether it's really a dun marking or not), a darker mask on her face, dark chocolatey colour on her points rather than black (check the roots of her hair) and often paler hair on the outside edges of her mane and tail.

To be honest I'd assumed the lighter-boned legs were as a result of the picture angle, but I see what you mean.

As for chocolate dun... I can't find reference to a chocolate dun @officially' in any of the breeds that do carry dun as a common dilute - Icelandics, Highlands nor Fjords mention it (although Highlands do have that elusive variant 'cream dun' :D - it's another type of dun going grey!). I imagine it would descibe something like a dark bay dun or some of the liver chestnut duns.

[Gill]

Here is a pic of our chocolate dun. You can clearly see the yellow bits. Smartie was about 3 on this pic. There is Welsh, TB and Arab in her breeding.

http://http://i23.photobucket.com/albums/b353/Gillb/smartie5.jpg

[chev]

She's beautiful Gill - but I suspect not dun. I think she's more than likely a sooty buckskin - that bay (dark bay in her case) with a cream gene. There's definitely no dun in Arabs, and I don't think it exists in TB breeding either. It's much more likely to be cream dilute then dun in Welsh breeding too.

Her colour isn't really flat enough to be caused by dun - that golden shade under the darker bits is typical of buckskin. Does she have a dorsal stripe? She doesn't show any other dun factor markings that I can see.

Absolutely beautiful colour though :D

[Gill]

Very interesting, thanks! Here she is with her mum, very dun indeed, or maybe not? We don't have Smartie any more as she is now grown up and in a good home so I can't check her for stripes.
http://http://i23.photobucket.com/albums/b353/Gillb/smartie2.jpg

[ambatt]

That is the same type of 'dun' colouring that occurs in Exmoors.

http://www.exmoorponysociety.org.uk/pictures.php