So what is this?

[color]

http://www.bilder-hochladen.net/files/3vua-5k-jpg.html


not a TB but a WB. Now some will say Sabino and some Dominant White and I still question HOW does anyone know for sure? Where is that fine line to determine Sabino or DW? There have never been all white WBs before, but the dam clearly looks like Sabino to me.

[RiddleMeThis]

I still question HOW does anyone know for sure?

Nothing is sure. Not even sabino.

As for how I differentiate between them? The exact same ways the researchers do. Inheritance Inheritance Inheritance.

Dominant White is a simple dominant like "E" over "e"
Sabino is an incomplete dominant like Cream is.

A horse like this, whose dam is highly marked and then produces a "white" foal, screams dominant white to me. Because it is most likely a dominant.

[color]

but we did never have whites in the WBs so how come all a sudden these whites now pop up everywhere? Is this maybe environmental mutations?

[RiddleMeThis]

but we did never have whites in the WBs so how come all a sudden these whites now pop up everywhere? Is this maybe environmental mutations?

Mutations happen much more frequently than people would like to think.

Every color but bay dun is a mutation.

Cream is a mutation.

Black is a mutation

Chestnut is a mutation

Frame is a mutation.


The dam is most likely for this foal ALSO dominant white and passes it on. It is likely that the mutation started with the dam here. A mutation can happen on any horse, and it doesnt even necessarily need to be a color producing one. It could be something like HYPP.

As for it being an environmental factor? I suppose it could be, depending on what you mean. There was a study done with foxes where wild foxes were bred in captivity and they started popping up with white patches, along with other things. So that could be a factor.

But if you mean something like Manchado where its most likely something the mare eats during her pregnancy, no or else we wouldnt see heritability.

So the easiest answer to "how come all a sudden these whites now pop up everywhere" is a new mutation.

[accphotography]

Given that every time they go looking, they find more dominant white mutations, it's not that surprising. KIT mutates alot apparently.

ACC

[summerhorse]

You can't tell by looking, you have to test and see WHAT the mutation is. But I don't know if SB1 has been found in WBs. Given the % of TB blood in WBs I would guess it is DW. I'd like to know the pedigree of the foal or at least the dam's side.

There have likely always been white WBs as there have always been white TBs and white Clydes and white Arabs... But the WB bias against white was even stronger than that in TBs and probably similar to that in Clydes. As in they tended to knock'em in the head! Or sell them off as part breds. I would suspect the knock'em in the head thing was common in Arabs too as they REALLY didn't like excess white markings much less white horses. (not counting greys which is odd when you think of it isn't it? =)

Thank goodness people the world over are finally figuring out a good horse is never a bad color.

[xfactor fan]

Just slightly off topic, but the fox thing is very interesting. Seems like the Russian fox fur breeders wanted an animal that was happier in captivity. So they started testing for fight/flight. And breeding animals that would let humans approach closely without fleeing.
For example if a fox would normally run at 20 ft, and a few would run at 30 feet, and another handful would run at 10ft, they selected for the 10 ft animals.

As the generations went by with selection, they were breeding friendly foxes that started acting more and more like dogs. Good news for the fox breeders, except that the more domestic the foxes got, the more odd white patches, shorter tails, and even markings like a border collie--white face, bib and white feet. Not so great for the fur breeders. They also had broader faces, and retained kit features into adulthood.

If anyone is interested I could dig up a link to the article.


I've always wondered if there is a parallel thing going on in horses. Are horses with large amounts of white, more human friendly than their solid siblings?

Maybe some of the farriers or vets or trainers, folks who have had the opportunity to handle lots of horses over they years would like to weigh in on this question.

[color]

My white horses are all very friendly and it is weird you would say this but ALL cremellos are super friendly and easy to deal with too.

[Jorge]

The dam looks sabino and the baby's ears too. The baby's coloring looks like there may also be another factor in the mix.