Could someone explain it to me? Our foal this year is such a strange color. She looks almost dun in some lights, and chocolately brown in others. She has a lot of white (4 stockings, belly spot, small star and snip), but she has white eyelashes and a ton of silver in her tail. Foal colors are so hard for me to judge anyway, do you think it’s just an expression of rabicano? It’s not white though, it’s very silvery. She has some silver hairs in her mane too, but very few.
Z is a dilution gene. It washes black to steel/white. It does not have any affect on red*
That certinatly looks like a silver dapple tail at first blush. Mane match? Black points that are mousey silver and not black? Can you post a full body shot?
What color are the parents? Red will hide Z, but black based colors can’t hide Z. So if you’re about to say both parents are plain jane bay and you end up with a silver dapple bay, I’m going to ask if the teaser pony stud got in with the mare. 
*Your mileage may vary. In Miniatures/Shetlands you can see “silver influenced” reds. People poo-poo this but DNA doesn’t lie.
Hi Julie
Sabinos can sometimes present with some of these features. If she tests negative for silver dapple I would guess this is what you are dealing with. BTW saw her on fb…she’s super cute!
I saw her on your FB page and see she has two bay parents so no silver dapple can hide in two bay parents. She is cute 
I had a filly who was born with a similar tail with two bay parents. Once the foal hair shed out she lost most of the white in the tail but does still have some strands running through her tail (so did her dam). Below are photos of her this year as an adult.
If you have a horse with the breeds in their pedigree that carry the Chocolate (or Silver Dapple) gene then it might be possible…though it doesn’t look like anything but maybe a wild bay and more likely a sabino trait or just one of those baby colors that will change as they mature… a few QHs have it, gaited horses have it, ponies have it, and Morgans have it. Other breeds that are related to those breeds can carry it.
It may be that we have an Alainn Shawn (RIDSH) daughter who is expecting a Hangon Johnny(RID) foal soon who is a Silver Dapple. She is chocolate with a light mane and tail and she has no dorsal stripe and we will see what she throws bred to a red chestnut who throws some flaxen manes. Still only 50/50 that she throws the Z gene IF she is a real silver dapple. The color likely came from an appaloosa stock horse dam and the spots and varnish can make it hard to know what the base color is on the dam. The mare is a wild thing and hasn’t been genetically tested. We are also expecting a Hangon Johnny(RID) foal from a stock type Grulla mare. A chocolate palomino can look like a silver dapple.
PatO
Wow, how interesting! And you all answered what was going to be my second question, if it’s from Sabino or something else will it stay that way. Sounds like probably not…like I said, foal coats/colors confuse me, they never quite shed out what I was expecting!
Most likely it’s baby flaxen, which looks light gray to white in this context, and is quite common on bay foals. I’ve seen it on black foals too - way cool. Sabino doesn’t do this though.
They nearly always grow out of it 
It can mimic a Gulastra Plume though, which is awesome.
It is possible she’ll keep it. I can think of at least two presumed sabinos who kept their “frosted” tails as adults…one a black IDxTB and the other a bay purebred Connemara pony. Both had Sabino roaning as well. The pony mare was DNA tested for silver dapple and was negative.
You are right, it is a baby coat and don’t get attached to the color until they are at least a 2 yo. PatO
