Starting to get into colors! Red zebra duns?

[Chatoyancy]

Hey all!

I've just started getting into labeling my horse colors, so I apologize for being a newb at this. I'm running into a few horses that I'm getting stuck on, so any help is appreciated!

1. I have several horses that are this color:
http://www.horseworldonline.net/horse/profile/37671
http://www.horseworldonline.net/horse/profile/40197
My gut says red zebra dun. Is that correct?

2. I have several horses with primitive markings -- is there any difference genetically between zebra duns and regular duns, or is it just a difference in phenotype?

3.
http://www.horseworldonline.net/horse/profile/39692
I'm pretty sure he is a red dun (assuming I am correct in my first question) based on his siblings and pedigree, but I'm not sure what the gray-ish cast is from. What would he be called?

[Chatoyancy]

Two more colors that I am completely stumped on -- nothing to do with red zebra duns though.

1.
http://www.horseworldonline.net/horse/profile/43781
http://www.horseworldonline.net/horse/profile/38666

2.
http://www.horseworldonline.net/horse/profile/43830
Child of one of the above horses and sibling of the other. Not only do I not know what to call the color, I am also stumped on the genetics behind it. What would cause the black mane but grey tail? Do we have a color guide on the greys yet? I don't understand how the grey genetics work.

Thanks everyone.

[nyraeia]

http://www.horseworldonline.net/horse/profile/37671
http://www.horseworldonline.net/horse/profile/40197
http://www.horseworldonline.net/horse/profile/39692

These are all red dun, yes. I've never heard of zebra dun and had to google a bit. According to this, the only colour that gets sometimes referred to as "zebra dun" is bay dun. So these are not zebra dun. It's the same gene, though. Dun varies in phenotype, so some horses may be more greyish or striped than others.

http://www.horseworldonline.net/horse/profile/43781
http://www.horseworldonline.net/horse/profile/38666

These guys are perlino, so bay+ double cream.

http://www.horseworldonline.net/horse/profile/43830

Black mane is fairly common for greying horses. They're just greying out unevenly. Grey overlays any colour, so the horse could be any colour underneath. Your horse is smoky brown underneath (you can tell from his foal picture).

Maybe a look at Totina's guide will clear the genetics side up a bit. If it doesn't, just ask :)

[Aela]

The first ones are red duns. "Zebra" is just a term used to discribe phenotypical primitive markings, so no difference in genotype. Horse number 3 is also red dun, possibly with sooty darkening him a bit

Onto the tricky non-dun colours, my bet would be buckskin with one copy of pearl for both of them, which causes pink skin, blue eyes and diluted coat.
The last one is clearly grey, but I'm too lazy to calculate his original coat. Grey is a dominant gene, which means both G/g and G/G carriers will grey out. Seeing as your stallion only has one grey parent, he's G/g and has 50% chance of passing the grey to his foals. Grey causes gradual depigmentation of the horse and all grey fade out differently. You hear shades like rose grey, dapple grey, light grey, steel grey and so forth, but they're all genetically the same

Hope it helps

[Aela]

I think both might be silver too

[Tawuwa]

Alexa is a perlino too.
Her dam Starlight is silver smoky brown. Starlight's sire, Erwin, is a cream carrier as well (silver smoky brown as well but only foal picture is shown so that's why it looks weird). Aj further in her pedigree is a silver smoky brown roan from palomino roan stallion and silver bay mare).

[Chatoyancy]

Awesome, thank you so much, guys! This really helps me figure this out, hopefully I will get better at doing this myself in the future.