Horse Color Genetics: Tovero

To review paint markings: T=tobiano, O=frame overo, SPL=splashed white, SB1=sabino.

One fact about paint-colored horses that a lot of people don't know is that there are a LOT of paints who have more than just one kind of pinto gene in their coat. They are called 'tovero', although tovero is a frustratingly broad term, and I'll explain why in a minute. For reference, here is a true tobiano, no other paint genes involved. Just so y'all know, those spots are called 'cat tracks' and are fairly common in tobianos.

Here is a person who is partially mistaken on the horse's color. He does have tobiano, but also a different gene as well. 

Compared to horse #1's markings, this horse is actually very different. First off, I know he carries tobiano because the white crosses over his back and his legs are white (see here to re-reference the definition of tobiano). But one of the rules of tobiano that I don't think I mentioned is that tobiano's always have very predictable face markings; a dark head with a 'normal' face marking. 

Now, the above horse has a white head and blue eyes. I've been learning lately that white eyes almost always indicate some kind of overo gene. Here is where it gets confusing: which overo gene is it? Reviewing, there is frame overo, sabino, and splashed white (read more about the difference's here). There are three options, and I'll walk you through why I think this horse is tobiano + splashed white.  Honestly, I am only guessing on the splashed white, it's only a hunch. 

First off, I know it isn't sabino. Frame and splashed white both sometimes cause blue eyes, sabino does not.

The above horse I've seen many people classify as tobiano. He is very beautiful, and I love his cat tracks. However, even though he displays all of the tobiano characteristics, his irregular face markings and blue eyes give away that something else is there. I'm not even going to guess whether he is splashed white or frame overo.

Something that is really important when breeding any paint to another paint at all is to have them genetically tested for frame overo, to save yourself the heartache of an OLWS foal. Because, in thinking that the horse #2 is just tobiano, they could breed him to another frame overo, and surprise! You have a dead foal. While I've talked a little bit about genes 'hiding', frame overo is one of the easiest to hide in a paint that you may think is just any of the other patterns. Even if you are almost positive of it being just tobiano, I would still test.

Horse Color Genetics: Wild Type Bay

Skipping the genome sequence review....

What is this wild type bay that you speak of?

Well, a wild type bay horse is a bay that has the black restricted to the mane and tail, and only a little on the legs. It's abbreviated by A+.

A+ is a different kind of agouti gene, but it still is agouti. Because A+ is dominant, even if the other copy of agouti is just a normal old A the horse will still show up as A+. Wild type bays are fairly uncommon; I've never personally seen one.

Wild type bays are typically a lighter color. Don't get me wrong, that doesn't mean that all lighter colored bays are wild type! There is a difference. Here's a good question: Is the horse below a wild type bay?

The correct answer would be no, probably not. While the legs may be covered up with white, you can still see that his hocks are black.  Besides, he is a very average shade of bay, and not particularly light.

Horse Color Genetics: Several Oddities and Mutations

Review: E=black, A=bay, G=gray, C=cream, D=dun, F=flaxen, Z=silver, T=tobiano, O=frame overo, SB1=sabino, Rn=roan, LP=appaloosa (not the breed), SPL=splashed white, CH=champagne

This may be an ongoing post, as soon as I learn about other mutations.

Sometimes, at very early stages as embryos, twins (which are extremely rare, not to mention if this ever happened) that are fraternal (nonidentical), will fuse together to become one. One foal will be born, but sometimes (if it were two fused together), some extremely crazy, nonplanned coat colors happen. Like these:

The first thing you may say, like me, is "What the heck is that!?!"

Well, I don't quite understand it, but I did explain it a little above. Wouldn't this be the craziest thing to own? Each chimeric foal has two sets of DNA. 

Something else that may happen with a horse that used to be a twin before they fused is a brindle coat pattern. Sadly, both the crazy 'paints' and the brindles is not inheritable; it is a mutation, and isn't able to pass it on, because those aren't neccesarily a coat pattern or gene.

The brindle coat pattern is both noninheritable, and inheritable. Generally, inheritable brindle doesn't look as cool, and is more faint.

Please don't mix up the first kind of chimeric horse with a horse with a somatic mutation, which looks like a 'birthmark'. It is basically just a horse that has a tiny bit of his coat 'turned off'. Like an EE AA, but the agouti got 'turned off' in a very small spot. Or it could be large, but it will be only one patch on the body.

I love this horse, he is so sporty!

This one may seem a little unexplainable, but it does make sense. I said there could be only one spot; why are there two? If you can imagine that the white spots from the paint pattern weren't there, you could turn that chestnut spot into one splotch. The white seperates it, though. So this horse is a palomino tobiano, with a somatic mutation that left a small patch of palomino undiluted.

For bay horses, the agouti gene simply got switched off a small place, leaving it black.

I don't quite understand how this horse's marking work, with the white on the bay, but she is so beautiful!

Horse Color Genetics: Seal Bay

Okay, I'm not going to do a review of all the letter sequences again, I'm guessing you will know what I mean if I refer to them.

One question that seems to come up a lot on a certain Facebook page for Equine genetics is, 'What is brown? Does it actually exist? And how do I define it as a color? How does it work genetically?'

First, let's talk about what brown actually is. When you think of brown, you may think of the color dubbed 'liver chestnut'.

This horse is pretty brown, right? There almost isn't another word for it. However, 'liver chestnuts' are genetically the same as a normal chestnut.

Kind of weird, I know, but true. So, back to the brown question. Does it actually exist? In a sense, yes. Well, the correct term for it is seal brown. What causes brown, and what does it look like?

While you may be confused, because this horse certainly doesn't look brown, that is only the name for it. It is also called seal bay, which is more correct.

Genetically, a seal bay (that is what I prefer to call them) horse has almost the same genome sequence as a normal bay. How do they look so different?

There is actually a different case between these than the first two chestnut horses. While they were very similar in genetic makeup and it was only due to how much black was incorporated in their coat, the bay's are different.

The difference is that the seal bay horse is the result of a different kind of agouti locus, abbreviated by At (actually, the t is supposed to be smaller). It isn't exactly a mutation, because many horse's have it, it is just a different kind of agouti gene. To non-genetic junkies such as myself, it is usually called dark bay.

One very confusing thing about seal bays is that they easily confused with black horses. Here are a couple pictures of both mixed together so you can see the confusion.

Just to help you lost folk out there, the first and third one's are black. They are, what you might call, 'fading black'. My own horse is a fading black, most black horse's are. Some happen to fade more than others. But can you see the difference? Most seal bays are lighter in areas such as the muzzle and flank area, while real black horse's tend to fade all along the belly and the muzzle will stay dark.

Just to put a smile on your face, here is a super cool Shire that is seal bay.

Deworming

One of Chocolate's larger problems is that she is allergic to pain. She basically hates anything that hurts, bites, stings, or doesn't feel good. Deworming falls into those catergories. Some horses don't put up a fuss at all about deworming; I don't think it's uncommon, though, for a horse to hate deworming.

For those of you that don't know, deworming is the act of giving your horse a very small amount of paste in a tube that kills any worms they may have picked up in the pasture. It doesn't sound like a big deal, but apparently it tastes horrible!

To give dewormer, you buy the little syringe that already has the paste in it (it's white and looks like toothpaste). You stick it in the corner of their mouth, keeping it pushed as far back into the mouth as you can (they will try to spit it out). Then you simply push the end, and the gross stuff squirts in. No biggy, right?

Wrong. I've heard from several people that using a syringe filled with molasses was a good way to 'desensitize' to deworming. I tried that. To my horror, Chocolate, who had never tasted molasses, still didn't believe that it wasn't dewormer. She balked at first. I tried again. But this time, she flew backwards, her hoof shot out, and before I knew it, I was lying on the ground. The next week, a pretty sore bruise broke out on my side where her hoof struck me.

The vet was pretty horrified that my own horse had struck me. He gave the horse's the dewormer that time, but he was very rough with them, backing them into a corner and shoving it in. The horse's, I'm sure, will never forget that.

I was tired of trying different things, and scared that I would get hurt. And, to my dismay, the vet instructed me to deworm at least every two months, because of the size of our pasture. To give you some perspective, most horses only need deworming every six months.

There was only one thing I could think of: make them want it. Make it taste good, and it would be so much easier. So I did just that. With their daily grain (plus maybe a little, I really wanted this to work), I squeezed the tube of dewormer in and mixed it up really good, adding just a little bit of molasses to help mask the taste. And you know what? It worked. They gobbled it up and never had a clue.

Deworming is now about the easiest health-related chore we have to do!