ChaCha!

[DianneC]

I have to laugh when the PROOF that a foal with a hard edged dorsal and legs stripes is NOT dun is the fact that the dam looks black, she even faded out so much one summer that I'm sure her dorsal was visible. There are many experts out there that are sure that a hard edged "eel stripe" dorsal is just counter shading because the coat color is not light. What they never consider is that it IS possible to have a dun gene and sooty (which produces counter shading) in the same horse. If a horse has a hard edged dorsal then the dun gene is present. If its got soft edges then its counter shading only. I've had foals born with stripes all over them, including a ventral stripe who turned black when they shed their foal coat. That is not the "normal" way a black horse is born, they are usually darkest grey shade with no stripes. It is common for a black horse to be born lighter and darken each year, but not to be born with stripes all over.
Rick had a foal I wanted to buy but got priced out of the running. She was born grulla with no beige and stayed that way. Her name is Chantilly Lace and I believe that she is still in So California.
The fact that the dun gene test requires pictures of both parents tells me they don't have it nailed down yet. Everyone is still learning. Sponenberg may be ahead of most of us, but he is still learning too.

[barbhorses]

I just praised you for a great link to a stallion that would have been thought of as a non-dun colored horse, but in fact is.

Yes, your links are useful, however, the question at hand hasn't been addressed before or people that have had foals that grow up to be black or bay are only thought of that way and not called dark grullas or dark duns.

My thinking was in scientific method, but I agree with you. Just takes one foal.

[barbhorses]

Which picture are you talking about Dianne? I saw several Standardbreds (I think) pictured who do not have dun factor in the breed, but in the summer faded out to look grulla.

In the interest of proving that a dark grulla or dark dun can produce a typical tan colored zebra dun or mouse grey grulla (or red dun), does anyone know of a dark grulla or dark dun produce a *typical* dun factor foal from a non-dun parent?

[barbhorses]

I remember two foals by Chinook and out of a bay Kiger mare and they produced sooty bays. Perhaps the dorsal seen on Chinook when he fades out is in fact counter shading? His sooty foals suggest that at least to me.

[barbhorses]

I agree with you on this subject as well Michelle, that this thread was absolutely hijacked. Is it possible to split it and put the comments pertaining to color in the color section?

[DianneC]

Maybe this would be nice to move over to the dun factor category. Sorry your thread got hijacked.
One more comment, its not surprising that a copper dun will throw a copper dun and not a light zebra dun. The sooty gene gets inherited just like any other gene.

[barbhorses]

I don't remember her being a dun (this was some years back anyways), would you mind posting some pictures of her?

[Michelle Clarke]

It would be interesting to see if a seemingly dark grullo/dun would in fact produce a true dun factor foal. It is hard to find stuff over the internet because many times good pictures are not taken. I again believe that the sooty and dun act together in a way that may make that difficult - I hope to find a different answer though.

Back when Loba and Pache were born, the photo quality was just not there. But I do know they had dorsals and leg bars. Does not explain why most Andalusians and Lusitanos are born striped and loose it after the foal coat. JP ran a 600 horse breeding farm at one point and most were born that way.

[barbhorses]

It would certainly be possible I think for a horse that is a grulla or a dun that is very dark due to a sooty gene to produce regular zebra dun and mouse grey grullas. Otherwise, you are assuming that every single dark grulla and dark dun cannot because all are homozygous for passing on the sooty gene. Which, I think we all know would be a totally false assumption. Thus, if the dark grullas and dark duns cannot produce typical zebra duns and grullas out of non-dun parents then we can say that the dun zygosity test and Dr. Sponenberg are correct in that dark "grullas" and dark "duns" do not have dun factor at all are perhaps have another gene at work (in regards to buff ear color). Perhaps the buff ear color is the result of counter shading at work?

[barbhorses]

The "dun" color that disappears on the Lusitano is one of the reasons why Dr. d' Andrade believed that the Sorraia was the ancestor of the Lusitano. Personally, I think it likely just a wavy coat or light playing tricks on the coat.

[Michelle Clarke]

Um, no. While I am sure some may be coat waviness, I've seen enough myself to see very visible striping on legs and dorsals - into the tail. Funny, the ones that grey seem to have the most striping.

[barbhorses]

Well, then I don't know what to tell you Michelle. Dun factor doesn't just disappear when the foal coat is shed.

[Michelle Clarke]

Yes, the appearance of such can. Just look up the Arabian foals that come out with dun looks and shed them out. It is common, so there is a question there as to just how many variations the dun can have, especially if it is a cluster of genes to begin with.

Ever consider it just might be a mutation...?

[barbhorses]

I think that there is a lot to do with the dun genes, especially when they are having such a hard time pin pointing it down. That tells me that there must be a cluster of genes. Perhaps, some are active and some are not to cause buff ear color on a black appearing horse? Or stripes that disappear when the adult coat comes in? I am no expert on genetics or color. My guess is just as good as anyone else's on this board.

[grullagirl]

It's interesting to note that a lot of the foals born with primitive dun markings that later shed out tend to be from breeds that have been established for a very long time( Andalusian/Lusitano and Arabian). I've always wondered since these breeds tend to be some of the oldest around that they might have had a very strong influence from the very first primitive type horses.