# Blue Eyes on "Black" Horses



## Broski1984 (May 28, 2010)

Hello,

I come here with a bit of a question!

My mother has a miniature horse mare which is dark brown/"black" with light blue eyes, and recently had a foal with the same blue eyes (although at least for now, he's a lighter color).

What color is she, and how common is this? A lot of people (myself included) have never seen a "solid black" horse with blue eyes, but that doesn't mean much.


























Note that on the foal, he was a mustard foal. He's been seen by a vet and being treated accordingly - but that's why he's a little "off" looking. He is eating, drinking, playing, etc. and looks _a lot_ better than when he was born.

The mother's a bit ratty looking, too. With everything (goats, sheep, pigs, ducks, geese, etc.) having babies, we've all been too busy to really brush her out, but I got on that after snapping the pictures.

The father is interestingly colored as well:









When he sheds out, he's a lighter silvery-gray. We thought (from his light mane/tail) that he was likely a dapple gray, but we've had him for three years now and his color has never changed. Slow to fade, or possible dilute of some sort?

Edit:
Found a picture of the stallion in the summer. Bit curious as to any opinion on what his color may be, too.


----------



## verona1016 (Jul 3, 2011)

Blue eyes are caused by one of two things: double cream dilution (e.g. cremello, perlino) or pinto pattern genes (splash and frame, to be specific).

Obviously, the mare and foal aren't double cream dilutes, so in this case that isn't the cause of the blue eyes. The mare appears to be black, and the foal appears to be bay or seal brown. The sire appears to be a flaxen chestnut, though I'm not 100% positive since the lighting in the winter photo isn't great, and the summer picture it looks like he might be body clipped.

That leaves pinto pattern genes (yes, the same ones that cause the loud white patterns in American Paint horses!). As I mentioned earlier, there are two pinto pattern genes known to cause blue eyes: frame (also known as lethal white overo) and splash. The mare is almost certainly frame, since frame is much more likely to express minimally (even without any white markings, such as with this mare and foal) and it looks like the foal inherited as well.

There's a genetic test for frame overo, which I'd highly recommend you do for the mare if you plan to breed her again, since frame overo results in a lethal white foal 25% of the time when you breed two frame-positive horses together. If your mare is indeed positive for frame, you should only breed her to stallions that have tested negative for frame to rule out the possibility of a lethal white foal. Testing is very easy (just pull a few hairs from the mane or tail and mail them in) and inexpensive ($25, IIRC)


----------



## Broski1984 (May 28, 2010)

verona1016 said:


> Blue eyes are caused by one of two things: double cream dilution (e.g. cremello, perlino) or pinto pattern genes (splash and frame, to be specific).
> 
> Obviously, the mare and foal aren't double cream dilutes, so in this case that isn't the cause of the blue eyes. The mare appears to be black, and the foal appears to be bay or seal brown. The sire appears to be a flaxen chestnut, though I'm not 100% positive since the lighting in the winter photo isn't great, and the summer picture it looks like he might be body clipped.
> 
> ...


Thank you for the information!

Like I said, I personally know little about horses (my mother has them; I have pigs). I'm unsure if she's gotten either of them tested (I doubt she has, because while she's fairly responsible with them, she hasn't much of an idea about "new" tests; I.E., ones her father didn't do in the 70s), but I'll run it by her and tell her to get it done.

I actually was a little concerned about it, because a friend of mine had discussed lethal white syndrome with me; which lead to limited research on my part, and informing my mother of the slight risk of it. I did not know testing was so easy though, so I'll run it by her.

Just to say, in the one picture, he hasn't been clipped. He just has a _very_ short coat in the summer. It ends up feeling more like a seal than a horse, haha.

Thank you again!


----------



## NdAppy (Apr 8, 2009)

Sire appears silver bay to me actually.


----------



## JCnGrace (Apr 28, 2013)

What is a mustard foal? I've never heard that expression and I love learning new ones.


----------



## CrossCountry (May 18, 2013)

JCnGrace said:


> What is a mustard foal? I've never heard that expression and I love learning new ones.


I would also love to know this!


----------



## Chiilaa (Aug 12, 2010)

A "mustard foal" is one that has "congenital hypothyroid dysmaturity syndrome". Basically, it is a foal that goes overdue, yet has characteristics of a pre-term foal - the softer coat and finer skin. They also have some issues with leg bones as well, that can lead to deformities in the forelimbs especially. It is linked to a particular group of weeds - if the mare ingests them during pregnancy, then they can cause a mustard foal. 

OP - if your mare is bred again, she will be considered "at risk". The best way to avoid it is to keep her on only hay, and make sure the hay is not contaminated with the weeds.


----------



## SunnyDraco (Dec 8, 2011)

Chiilaa said:


> A "mustard foal" is one that has "congenital hypothyroid dysmaturity syndrome". Basically, it is a foal that goes overdue, yet has characteristics of a pre-term foal - the softer coat and finer skin. They also have some issues with leg bones as well, that can lead to deformities in the forelimbs especially. It is linked to a particular group of weeds - if the mare ingests them during pregnancy, then they can cause a mustard foal.
> 
> OP - if your mare is bred again, she will be considered "at risk". The best way to avoid it is to keep her on only hay, and make sure the hay is not contaminated with the weeds.


Only for the last trimester, my mom had a mild case mustard foal. She has been battling mustard in her pasture for years, after her mustard foal, she dry lots pregnant mares when they start the last trimester


----------



## Chiilaa (Aug 12, 2010)

SunnyDraco said:


> Only for the last trimester, my mom had a mild case mustard foal. She has been battling mustard in her pasture for years, after her mustard foal, she dry lots pregnant mares when they start the last trimester


It's more to do with the time that they are on the pasture - the weeds only grow at certain times of year. So that is why there is a loose correlation between mares that go overdue and mustard foals - they get more time on the pasture that is effected. But yes, usually that is the last trimester, so always a good thing to be doing if you know you have this issue


----------



## SunnyDraco (Dec 8, 2011)

Chiilaa said:


> It's more to do with the time that they are on the pasture - the weeds only grow at certain times of year. So that is why there is a loose correlation between mares that go overdue and mustard foals - they get more time on the pasture that is effected. But yes, usually that is the last trimester, so always a good thing to be doing if you know you have this issue


They grow with everything else but there are fewer cases of mustard early spring because much of the last trimester is still winter and the mustard doesn't begin to grow until it is warm. Foals born later in the year have had more exposure to mustard through the last trimester. The only change my mom made was a dry paddock for the last trimester and has not had any more mustard foals. The mustard is still there in the pasture they are on from conception until the start of the last trimester. 
_Posted via Mobile Device_


----------



## Broski1984 (May 28, 2010)

I appreciate the information on that. Despite it being apparently fairly common, it's quite hard finding much information on mustard foals; even the vet didn't know much, just that it was what was wrong with him.

Fortunately, he had a _very_ minor case of it. His coat was normal, he could eat properly, he could stand and lay down on his own, etc.; mostly, it was cosmetic aside from his front legs being a little soft. Could of been a lot worse.

Despite having a hard time finding information on preventing it/what causes it, it apparently is being very common this year up here. We're (the area) getting a lot of goats and calves with bad selenium deficiencies, too.

That combined with the "uncharacteristically-bad-even-for-us" winter has made Northern Indiana/Southern Michigan a lovely place this year. 

The ticks are just a bonus!


----------



## SunnyDraco (Dec 8, 2011)

Broski1984 said:


> I appreciate the information on that. Despite it being apparently fairly common, it's quite hard finding much information on mustard foals; even the vet didn't know much, just that it was what was wrong with him.
> 
> Fortunately, he had a _very_ minor case of it. His coat was normal, he could eat properly, he could stand and lay down on his own, etc.; mostly, it was cosmetic aside from his front legs being a little soft. Could of been a lot worse.
> 
> ...


http://www.vetmed.wsu.edu/depts-fdiu/research/MustardFoalsReport.pdf

It is a long read but lots of research and findings, following their suggestions has kept my mom from having another mustard foal, even out of the mare that had the affected foal. If you have such a wide spread problem in the area unlike previous years, I would be examining the hay. If there was a mustard outbreak in hay fields that everyone is buying from, that would explain the widespread outbreaks. 

In the case of my mom's mustard foal, the mare went weeks past her 340 day mark and delivered a small filly that was essentially a preemie in development, with the preemie coat as well. The vet was called out because 4 hours after birth, the filly still could not stand on her own. She ended up getting a transfusion due to low antibody levels and a shot to help with her tendons. She also had a parrot jaw but still managed to nurse adequately. After a couple days, she was finally able to stand up and lay down without assistance and became a normal active foal after 3 weeks, and quite expensive with the vet care required. That was just a mild case and the vet was very experienced with mustard foals, other owners aren't so lucky.


----------



## Broski1984 (May 28, 2010)

SunnyDraco said:


> http://www.vetmed.wsu.edu/depts-fdiu/research/MustardFoalsReport.pdf
> 
> It is a long read but lots of research and findings, following their suggestions has kept my mom from having another mustard foal, even out of the mare that had the affected foal. If you have such a wide spread problem in the area unlike previous years, I would be examining the hay. If there was a mustard outbreak in hay fields that everyone is buying from, that would explain the widespread outbreaks.
> 
> In the case of my mom's mustard foal, the mare went weeks past her 340 day mark and delivered a small filly that was essentially a preemie in development, with the preemie coat as well. The vet was called out because 4 hours after birth, the filly still could not stand on her own. She ended up getting a transfusion due to low antibody levels and a shot to help with her tendons. She also had a parrot jaw but still managed to nurse adequately. After a couple days, she was finally able to stand up and lay down without assistance and became a normal active foal after 3 weeks, and quite expensive with the vet care required. That was just a mild case and the vet was very experienced with mustard foals, other owners aren't so lucky.


I will look at that! Thank you for the information.

Glad your foal turned out alright, even if she ended up being a bit expensive!


----------



## verona1016 (Jul 3, 2011)

NdAppy said:


> Sire appears silver bay to me actually.


That would have been my other guess- knowing that he's not clipped in the summer photo it makes more sense.


----------



## stevenson (Sep 12, 2011)

I would be doing weed control on my pastures and also be feeding a quality hay.
the blue are very striking and I have no idea what causes the blue eyes other than some genetic trait. the stallion would be considered sliver. I dont know what color your mare would be her hair coat is a mess and not shed out. I would also give her some extra hay or pellets she looks sort of thin. (off point but then again so is a lot of this thread.. sorry)


----------



## JCnGrace (Apr 28, 2013)

Chiilaa said:


> A "mustard foal" is one that has "congenital hypothyroid dysmaturity syndrome". Basically, it is a foal that goes overdue, yet has characteristics of a pre-term foal - the softer coat and finer skin. They also have some issues with leg bones as well, that can lead to deformities in the forelimbs especially. It is linked to a particular group of weeds - if the mare ingests them during pregnancy, then they can cause a mustard foal.
> 
> OP - if your mare is bred again, she will be considered "at risk". The best way to avoid it is to keep her on only hay, and make sure the hay is not contaminated with the weeds.


 
Thank you for defining it Chiilaa.


----------



## FrostedLilly (Nov 4, 2012)

Ad a side note, congenital hypothyroidism is not solely caused by plants in the mustard family. There has been a link between high levels of nitrates in hay and the syndrome as well. A second cut hay cut after a frost will be high in nitrates. The breeder where I took Lilly lost a few last year and that is what the vet thinks was the cause. Her hay didn't have weeds in it and here in the land of ice and snow, there were no actual weeds to ingest at the time of foaling. Her foals didn't survive, so I'm glad to see he's doing ok. His blue eyes are super cute!
_Posted via Mobile Device_


----------

