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Lethal Whites

Equine-Reproduction.com Bulletin Board » Equine Genetics » Lethal Whites « Previous Next »


Author Message
 

melissa Wise
Posted From: 64.12.116.22
Posted on Monday, April 12, 2004 - 01:36 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I am heart broken again, this is the third year in a row that my neighbor has had a lethal white foal! Her mare carriers the Overo Lethal White gene, the stallion she keeps breeding has the gene also. I couldn't believe last year when she bred to him again, we all kinda knew she was going to get another lethal white baby. People need to understand that overo bred to overo if both have the lethal gene, will get a lethal white foal 25% of the time, it is a 1 in 4 chance! But still people bred, and more and more lethal white babies are being born, if you'v never seen one, pray you don't, they are angelic snow white, born heathly and running and playing, then, after a few hours or even a few days they start to suffer, they roll in pain because their bellies hurt so bad! It is the most horrible sight you'v ever seen! And they most humane thing to do is put them down, and believe me, it's the worst experience you could ever imagin going threw! So please, get your mare checked for the lethal white gene, and research your stallion, and see if he is tested also, the least lethal white born the better!
 

Anonymous
Posted From: 24.98.62.68
Posted on Tuesday, May 04, 2004 - 03:11 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

What does the color lethal white do to the foal? I really don't understand...could you explain? Thanks
 

Sandy
Posted From: 205.187.220.121
Posted on Wednesday, May 05, 2004 - 01:05 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Melissa,
I also have a problem with people who breed two known lethal white carriers together year after year, I think it is totally pointless.
I have spoken to a few overo breeders who say that to them it is worth taking the risk to try to get that one "perfect" overo or frame overo. They actually WANT their horses to carry the lethal white gene! They will test for it hoping that the horse has it! I think it is totally inhumane and rediculous.
To Anonymous:
It isn't so much the color "lethal white", that is just what they call it. It results from two overos who carry the gene being bred and therefore having a totally all white foal, and therefore the term "lethal white". These foals are born with a genetic defect that will result in them having severe intestinal problems and they will eventually colic and die.
I'm not a Paint breeder, so I really do not know the whole workings of the defect, so that is really all I can tell you about it.
 

Kristin
Posted From: 68.105.225.13
Posted on Saturday, June 19, 2004 - 05:50 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Not all lethal white die.... MOST are born with an incomplete digestive tract...they develop colic like symptoms and must be put down. Some lethal whites do not have the birth defect though...there are horses that have been born that test positive for both genes for lethal white and are perfectly normal....except for the excessive white color. Lethal white is also present in other breeds of horses..
 

Sandy
Posted From: 4.227.133.213
Posted on Sunday, June 20, 2004 - 12:32 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Kristin,
That's interesting to hear that some live. I have checked the UC Davis site about this gene, and it is stated on there that a carrier of two sets of LWO genes does not live.
Also, can you tell me what other breeds carry the LWO gene? I imagine if there are other breeds, like say for instance a QH that carries the gene, then there had to have been a Paint in their background somewhere.
I find this whole LWO gene stuff quite interesting as I just had a colt born (Miniature horse) out of a Tovero mare and a solid buckskin stallion and the colt is a frame overo. Now everyone is telling me to get him tested for the LWO gene. I am going to have him tested because I'm thinking of keeping him as a breeding stallion, (depending on how he turns out when he's older and how he does at the shows), and I'd personally like to know if he does carry the gene so I could avoid breeding him to mares that also carry the LWO. So that is why I have started doing so much research about this defect and the chances of getting a horse that is lethal white.
 

Kristin
Posted From: 68.105.225.13
Posted on Sunday, June 20, 2004 - 10:05 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sandy,
I don't know how many lethal whites are born with out the defect, b/c most people put them down after they are born, but I do know that occasionally some DO live. I know that they have found the gene for lethal white in other breeds, and I do think that one was QH. But it is not due to the fact that the QH has paints in its pedigree as you suggested. If that were the case, it would not be a QH at all!! It would have to be a paint, b/c if a horse has a paint in it's pedigree ANYWHERE AQHA will NOT Register it. It is probably due to the fact that paints originally came from genetic crop outs, or Mutants, What I mean is that if you trace a paint back far enough, it eventually has two solid parents. You will occasionally get a baby from two solid quarter horses, or TBs or a cross of the two...that has alot of white on it. For example...check out the double registered Thoroughbreds at www.painteddesert.net These horses all came from Regular thoroughbreds who had a baby with alot of white on them...then people began breeding those babies with alot of white to get more babies with even more white.
I hope this has helped some...I am no expert, but this is what I know
 

Kristin
Posted From: 68.105.225.13
Posted on Sunday, June 20, 2004 - 10:19 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

OK, I just did a little research. Here is what I found. Lethal white IS always fatal according to what I read...But I have read stuff before about horses that tested to have both genes for overo lethal white, and were very much alive...I guess they were a "fluke" the exception to the rule. I think the biggest problem with lethal white is that people will often have a baby put down if it is born white or mostly white, but not all white horses have lethal white syndrome. Lethal white CAN be found in Pintos, Quarter HOrses, Thoroughbreds, and EVEN IN TOBIANOS. So just because a horse is not a frame overo does not mean it is not a carrier. In the same sense, Not all frame overos are carriers for lethal white. Here is a link to an article that APHA has on the topic. Sorry about the confusion, and If I find the info on the LIVING LETHAL WHITES I will post it for you.

 

kristin
Posted From: 68.105.225.13
Posted on Sunday, June 20, 2004 - 10:20 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

http://www.apha.com/breed/lethalwhites03.html
 

Sandy
Posted From: 4.228.252.23
Posted on Monday, June 21, 2004 - 06:29 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks Kristin for the info.
I had no idea that LWO gene could be found in QH and TB. I mean, most people who own a QH or TB wouldn't even think of testing that horse for LWO. I know I wouldn't just because of the fact that it is a gene that has always been linked to Paints and Pintos.
And if LWO is found in a Tobiano, then wouldn't that make that horse a Tovero? Everything I have been reading up on Lethal White Overo leads me to believe that the horse would have to have Overo breeding somewhere down the line in order to carry the gene.
I do know there are crop-out Paints born in the QH's. Doesn't the AQHA state that if a horse has white extending above the knees, it cannot be registered?
I'd be interested in seeing some information on these other breeds that carry the LWO gene that do not have any Overo breeding in their lineage.
 

Sandy
Posted From: 4.228.252.23
Posted on Monday, June 21, 2004 - 06:45 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Kristin,
Okay, I just checked out the two different sites that you had posted links for.
the painted desert site does state that an all white TB horse has NEVER produced a lethal white.

Also the ApHA site states:

Occasionally, solid white or nearly solid white foals are born to Paint Horses of overo lineage. Initially these foals appear normal, but after a short period of time show signs of colic due to an inability to pass feces.
This condition, referred to as Overo Lethal White Syndrome (OLWS) is always fatal, and results in both emotional and economic loss to breeders.

So, I think what you're saying is that there are ALL WHITE horses that are born of other breeds that live.
But the horses that are carrying the LWO gene, do not live as stated by the APHA. The APHA site also states that a true LWO carrier does have Overo lineage.
As for the painted TB's and all white TB's, they are carrying a Sabino gene, not the Overo which is responsible for LWO syndrome.
I breed Appaloosas mainly, and I do know that there are all white Appaloosas that are born too. But it is not the Overo gene that is responsible for that. They are actually called few-spot leopards and are homozygous too.
If you find something that states that there are horses out there that do not have any Paint or Pinto breeding that carry the true LWO gene, I would find that most interesting! Because this really has me curious now....I just love doing research on color genetics.

 

Sandy
Posted From: 4.228.252.23
Posted on Monday, June 21, 2004 - 06:58 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sorry, I realized that I posted "horses that are carrying the LWO gene, do not live"
I meant to say that a horse carrying the double gene L/L (A true Lethal White) do not live.

Here are a few other excerpts taken from the APHA site that I found most interesting.

There are some Paint Horses born completely white with blue eyes that survive. These are often termed "living lethals," a misnomer as they are not homozygous for the lethal allele.

Overos can carry either (N/N) or (N/L). We have not found a living adult horse that has two copies of the lethal sequence (L/L), and we have tested several all-white Paints.

We have found carrier horses in overos, tobianos, toveros, Breeding Stock, crop-out Quarter Horses and Pintos.
 

Barb
Posted From: 203.220.225.171
Posted on Tuesday, June 22, 2004 - 09:25 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The trouble is that there are actually 4 coat colour patterns. Tobiano, Splashed White, Sabino and Overo. The APHA lumps them in to two categories for registration. Tobiano and Overo.

A true overo bred to true overo has 25% chance of producing a lethal.

You can also get mixture of two or more coat patterns for instance as in Tobero where the horse carries tobiano and overo genes.
If you breed a tobero to an overo you may also get a lethal.

You cannot get an overo that is N/N.

All horses with the overo pattern carry one copy of the lethal gene and so are N/L.

Lethal whites are foals that got one copy of the gene from each parent and so are L/L

There are no surviving Lethal Whites otherwise we would see horses that were homozygous for overo.

Any horse that claims to be an overo that is N/N is not a true overo, more likely it is a sabino.
It may say it is overo on the rego papers but if it does not have the lethal gene it is not an overo.
 

Barb
Posted From: 203.220.225.104
Posted on Tuesday, June 22, 2004 - 10:40 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Kirsten, I have never heard of the lethal gene being found in Thoroughbreds. I have heard of high white or all white thoroughbreds, this is attributed to the sabino gene.

I suspect that the white paints on the APHA article on your link are sabero ie. they carry both the sabino and overo genes.

There are also Paints which are called medicine hats they can be all white with just a little bit of colour on the top of the head and ears.
These are generally sabino/overo crosses, less commonly tobiano/overo crosses or a combination of all three.

As for quarter horse cropouts carrying the lethal gene. Overo may be expressed in a very minimal amount and a horse may be mistaken to be solid when it is actually carrying the overo gene.

This could have been overlooked when the QH breed was first established. Most QH cropouts would most likely be sabino though I would say.

One could ponder about some breeders passing their solid foals off as Quarter Horses.
 

kristin
Posted From: 68.105.225.13
Posted on Wednesday, June 23, 2004 - 05:00 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

http://www.netpets.com/horses/healthspa/lethal.html
Check out this webpage, It has an article about
OLWS it is a genetic mutation that generally occurs near the overo gene. The Article states..."Horses that carry this gene are most commonly overo white patterned horses (frame overos), but there are exceptions. The defective gene has been found in American Paint Horses, American Miniature Horses, Half-Arabians, Thoroughbreds, and cropout Quarter Horses (foals born to registered Quarter Horse parents that have too much white to qualify for registration with the American Quarter Horse Association).
OLWS foals have blue eyes and are completely or almost completely white"
 

Sandy
Posted From: 4.228.165.26
Posted on Wednesday, June 23, 2004 - 06:51 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Barb,
You say that ALL overos carry the lethal white gene? And if it is tested N/N then it is a sabino, not an overo....could you tell me where you found this information?
Eventhough the APHA lumps sabino and overo into the same category, they are clearly different coat patterns. The sabino may have white in the same areas as the overo, but the sabino's white is a lot more "broken" looking, as though it had a kind of roaning around the edges of the solid color, or more of a splashed look. Whereas the overo has clean, crisp looking lines. I have known a few people who have had what have looked like true overos born, out of at least one overo parent, and have tested N/N. So, according to what you are saying, these foals would not be overo?
I have a suckling miniature horse colt that I have been told by numerous Paint and Miniature breeders is a frame overo. His dam is a tovero, or tobero, whatever you want to call it, she is from a tobiano dam and overo sire, and the colt's sire is a solid, with unknown color background. My colt does not have any of the characteristics of the sabino, no roaning on the edges, or splashed look. I have been thinking of having him tested for the LWO, but if he isn't even an overo, then I won't bother, but the funny thing is, his papers will state that he IS an overo even if he does test N/N.
I would really like to see the information stating that ALL overos test N/L if you know where I could find that.
 

Kristin
Posted From: 68.105.225.13
Posted on Wednesday, June 23, 2004 - 10:11 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sandy,
Not All overos ar O/o (the overo lethal white is symbolized correctly as an O -dominant or o -recessive. The Gene for overo lethal white Is a MUTATION. It is not a NORMAL gene. It is a gene that mutated, and then got passed around the population by breeding mutants to mutants. It IS more common in Overos, but NOT every overo has it. Overo is a term that describes a horse with no white crossing it's back between the withers and tail. A tobiano is one that has white cross over the back, and a Tovero is a horse with white that crosses it's back, but that has traits of an overo also, irregular edges, excessive white onthe face, etc, etc) Tobiano is only expressed by one gene, that is why a Tobiano CAN BE HOMOZYGOUS! the Overo pattern is controled by AT LEAST THREE genes, they are not sure exactly how many for sure. It is a Dominant trait, and that is where alot of the confusion comes from. It is not the ACTUAL OVERO genes that cause lethal white. The three types of overo are the sabino, splash, and frame overos, but a horse can have more than one of these patterns all mixed together....that is the case with most overos you see. The lethal white MUTATION is MORE common in frame overos, but it can be present in a sabino overo, splash overo, tovero, and EVEN tobianos!!! If your colt is marked with no white crossing his back between the withers and tail head, THEN HE IS AN OVERO. There is not a TRUE overo. Overo is a word that describes the PHENOTYPE (how the horse looks) NOT the GENEOTYPE (which genes he has. What does your colt look like? Frame OVeros will have color down their back, under their belly, and down the chest and butt.. ....it frames the white like a picture. If you are concerned about it, go ahead and have him tested, b/c if he is a overo at all, or even if he were a tobiano, he could have the mutated gene. Even if he does have it, as long as the mares don't have it, you will NOT have a lethal white foal.

I want to make SURE you don't think that all overos carry the gene b/c that is a myth. Infact, I will post some links to webpages of stallions who have been tested negative for lethal white!

I hope this helps, I will also post the address to my webpage...we had a frame overo mare...that way you can see what one looks like for sure
Her name is Red's War Bonnet, it is hard to see the red under her belly, but you can get the idea.
http://www.paintaholic.com/html/about_us.html

There are some good pictures of her from various angles on this page too.

http://www.paintaholic.com/html/about_us_photos.html

 

Sandy
Posted From: 4.228.243.96
Posted on Thursday, June 24, 2004 - 06:02 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Kristin,
I had wondered about the post from Barb that said that ALL overos carry the lethal gene, because I just have never heard that before at all! And I know there have been quite a few overos that do test negative for lethal white.
My colt is exactly how you describe the frame overo. He has absolutely no white that crosses over his body anywhere, including the neck. His dark color covers his entire neck, chest, down the front legs half way, face, back and down the back side of the butt cheeks. He also has one small patch of dark under his belly that you really can't see unless he's on his back...lol. But, the only difference is that he does not have any face white, other than a small white spot under his chin, which you wouldn't even know was there unless it were pointed out to you.
There is a pic of him on my website, it only shows one side of him, but the other side is marked almost identically to the side that is shown in this picture.
www.angelfire.com/ut2/sbr/index.html
Just go to the new arrivals page and he's at the top.
 

Barb
Posted From: 203.220.225.56
Posted on Thursday, June 24, 2004 - 08:43 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

There is a very good book called Horse Colour Explained by Jeanette Gower. I'm sure you could find it on the net somewhere. It explains the differences in coat patterns. I breed Paints so I read alot of information about breeding for colour.
As I said I think alot of the confusion comes from the fact that Sabino, Splashed White and Overo are all being called Overo. I believe the four coat patterns should be registered separately.

Overo meaning eggshaped. The white tends to run horizontally along the body. Body white tends not to cross the spine. Legs are usually dark up to the knee (unless sabino is present).

In the sabino pattern the white appears to run vertically up the legs and vertically up the body. Leg markings are often spear shaped. Sabino is often confused with overo or roan.

 

Barb
Posted From: 203.220.225.56
Posted on Thursday, June 24, 2004 - 09:55 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sandy if you find a photo of a horse that claims to be an Overo that is OLWS negative I bet you that it displays sabino characteristics.
If you find one that doesn't, let me know. I have never seen one that doesn't have white legs.

My stallion is an overo. He has four solid coloured legs I won't even bother to get him tested because I KNOW that he will carry the Lethal gene. I will happily breed him to solid mares and sabino mares and I'd consider tobiano mares but I would never breed him to another overo or a tovero.
I cannot understand the breeder that Melissa mentions in her post, knowingly risking getting another lethal.
If they would just breed to a solid coloured horse or a sabino they would not have this risk.
Breeding to a sabino would give more chance of colour. Though I am not really into mixing the colour patterns.
 

Barb
Posted From: 203.220.225.56
Posted on Thursday, June 24, 2004 - 10:09 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I would just like to add that Tobianos do not carry the lethal gene unless they have overo parentage. If they carry the lethal gene they are actually a genetic Tobero.

You can see how when people start mixing the colour patterns how the trouble starts.
 

Kristin
Posted From: 68.105.225.13
Posted on Thursday, July 01, 2004 - 10:36 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sandy, I sent you an email.... I just got back from APHA World show.

I would just like to add that a horse can have genes for all three overo patterns, FRAME, SABINO, AND SPLASH, so just because a horse has white on it's lower legs does not mean it is not a TRUE OVERO. My Horse is an Overo...He has pattern traits of all three genes, and has thrown foals that were mixtures of the three types of patterns, and he has also thrown some that showed only Sabino, some that showed only frame, and some that showed splash overo markings. NOT ALL OVEROS ARE CARRIERS OF THE LETHAL GENE. and it is TOVERO, not TOBERO... no point in arguing these points....I've made my statements, so I'm done.
 

Sandy
Posted From: 4.228.243.188
Posted on Friday, July 02, 2004 - 03:25 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hi Kristin,
I didn't get your email....don't know what happened there.
Did you have a chance to look at the picture of my colt on my website? I have been checking TONS of websites on Overos, splash, sabino and tobiano. I honestly think that my colt probably does have several different patterns mixed as you said. Considering he has all white legs, that is a characteristic of splash, and also his small chin spot. BUT everything else I have been seeing says that if a horse has a solid or regular marked head, that is a Tobiano. And my colt doesn't have any white crossing his spine, so that is Overo. So, could he actually be a Tovero then? And if he is a Tovero, that would mean that he IS carrying the Overo gene and possibly the lethal, right?
If you'd like, I can email you some more pictures of him so you can get a better look.
Thanks for your help.
 

Barb
Posted From: 203.220.225.20
Posted on Saturday, July 03, 2004 - 01:03 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

In the Australian Rule book Kristin the term used is Tobero but many people here do use the term Tovero. Both mean the same.
Yes many horses carry genes of several colour patterns and therefore can pass on these traits singularly or mixed.
Yes overos can have some white on their legs.
I am not disagreeing with you on these points.

I am simply trying to say that a Sabino is Sabino not an Overo.

A Splashed white is a Splashed white not an Overo.

An Overo is an Overo wether it be expressed minimally or loudly.

When these horses are registered however they are indeed all called Overo.
I think this is wrong.

The overo gene is responsible for Lethal White foals. Not the Sabino gene and not the Splashed White gene.



 

Barb
Posted From: 203.220.225.206
Posted on Saturday, July 03, 2004 - 02:18 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Kristin, I am not having a go at you, just trying to clear up the confusion. I have been looking at more sites on the web and what I am seeing is that in the US people are using the terms Splash and Frame to describe Overo.

The overo gene can be expressed with just a little white or a lot. We would use the terms minimal, moderate, loud and frame to describe Overo, but not Splash incase this could be confused with Splashed White, which is a different pattern all together.

We don't have many Splashed whites in Australia as they are predominantly deaf.

 

Kristin
Posted From: 68.105.225.13
Posted on Saturday, July 03, 2004 - 10:35 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

BArb,
but according to everyone who has done research, the OLWS Gene is a mutation and is not the same as the gene for frame overo....that is why I say that not all overos are going to test positive. It is much more likely in a frame, but not 100%.

Sandy,
I looked at the picture of your stud....to me I would call him a splash/frame overo. He has characteristics of both. I have just returned from APHA World, and I saw quite a few frame overos who had predominately dark faces. My ver first impression of him was splash though
 

Sandy
Posted From: 4.228.249.101
Posted on Saturday, July 03, 2004 - 12:50 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks Kristin,
I think I would agree with you on the splash/frame overo for my colt.
Do you think it would be worthwhile to have him tested for OLWS?
I am currently looking for a mini mare to purchase for breeding to this colt in a few years, and I cannot decide whether to look for one that is overo or one that is solid. If there is the possibility that he could test positive, well then of course I would probably want to stay away from breeding him to another overo, but if there is the chance that he is negative, then I would like to breed him to an overo.
I think I might just go ahead and spend the $50 to have him tested....what the heck.
Barb:
I have the book you referred to, Horse Color Explained by Jeanette Gower. It is a very informative book for sure. I do see in there that there are definite distinctions between Tobiano, Overo, Splash, and Sabino.
My problem is I am dealing with a miniature horse, and in miniature horses, people are constantly breeding different coat patterns together. It is actually highly acceptable in the miniature breed to breed pinto and appaloosa coat patterns together. So, needless to say, you just never know what exactly is in your horses' line of breeding as far as coat patterns go. That is why I have been having such a difficult time determining what my colt actually is. From what I know about my colt's sire and dam's backgrounds there is quite the mix. My colt's dam is reported to be a tovero. From the pictures I have seen of her parents, her dam was a tobiano and her sire was solid.
My colt's sire is a solid, but has one small roan type spot on his hip. His sire is a solid, from what I could tell, he is a perlino, so very hard to see if there were any markings. His sire, I was told, was an appaloosa. My colt's sire's dam is a solid.
So as you can see, I was quite shocked and surpised when this colt was born, considering he comes from a mostly solid background. But, my mare has always thrown very loud color no matter what she has been bred to.
 

Barb
Posted From: 203.220.224.117
Posted on Monday, July 05, 2004 - 08:00 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Kristin, the Overo gene WAS caused by a mutation just like HYPP was but it passes down the generations, it doesn't just suddenly decide to mutate here and there at random. It has either been passed on or not. If you have an overo it carries one copy of the lethal gene. It's only when the foal inherits a gene from each parent that there is cause for worry (lethal foal).

The reason there is more chance of a lethal from a frame is that the horse is just that - a frame OVERO. The Frame is actually carrying one overo gene and if bred to another horse that is carrying overo there is a 1 in 4 chance of a lethal.
OLWS gene is not a bad thing, unless you breed your horse to another horse that is carrying overo.

Like I said before Sabinos do not carry the overo gene though they are classed as overo by the APHA.

Sandy I think it would be a good idea to get your horse tested for OLWS if you are unsure and then you will know. If he tests positive it just means that he has a greater chance of throwing colour on his foals because he certainly looks like a Tovero so could throw Tobiano or Overo or Tovero foals or of course Solids. If his Dad has a roan type spot on his hip it could be an appalossa marking or less likely sabino (because you know there is appaloosa parentage) and so your horse could be carrying that as well. As yet there is no test for Sabino.


There have been ongoing discussions on the Paint Horse of Australia bulletin board regarding the overo gene, it would be interesting for you to visit and peruse and I think it may clarify things for you.

If your horse tests positive for OLWS then it is up to mare owners to make sure their mares are not carriers and then there is no chance of lethals.
 

Barb
Posted From: 203.220.224.117
Posted on Monday, July 05, 2004 - 08:21 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Kristen, you mention in your post a gene for Frame Overo I have never heard of this.

To my knowledge there is a gene for Overo and other factors are at work to determine how loudly this will be expressed.

Can you tell me where you read this.
 

Anonymous
 
Posted From: 205.188.116.65
Posted on Thursday, December 22, 2005 - 12:41 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have to add a few comments here because I have read alot of misconceptions I have overos and I have had all the mares tested and have done alot of studying on the lethal whites, not all frame overos carry the gene, you have loud frame overo crop out quarter horses that do not carry the gene you have solid paints tobianos and some quarter horses who do carry the lethal white gene and the other thing in here I read is that some lethals can live this is not true but you can have an all white paint but just because it is white does not make it a lethal white I do have a loud frame overo mare who is overo paint bred four generations who does not carry the gene, and a minimal white who is almost all quarter horse with only one paint horse on her papers who does carry the gene
 

Kim k
Breeding Stock
Username: Kimk

Post Number: 192
Registered: 04-2005
Posted on Thursday, December 22, 2005 - 09:30 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have to totally agree with Anonymous. This is what I have stated. If you are concerned about the lw then test everything because the gene is being found in almost every line of horses. I have a long time friend, that is a vet and most of the lw foals that they ever see comes from bay qh mares with the max white on the mare...ex high white stockings, most white on face possible. Another friend(been in the business for many years breeding for paint, qh and tb, been to the world shows, racing on the track ect.)and she has always told me if buying a qh for breeding to paints make sure that you look for the most white possible as they have also seen that it helps produce that colored baby. Now, there is no scientific studies done on this but just from thier many years experience has proven this. It is more likley to help get that spotted overo if the qh has high whites. It is true that not all overo carry the gene but it is more typically seen in a frame overo. I have a friend that has a bay solid breeding stock and again she had a lw foal. So you must not have spotted animal to produce a lw foal. The gene hides and the associations are finding this out. And the more crossing one is doing with the different patterns one might think that a toby will not carry the gene--just not true not only can it show up in the toby, but that toby may have overo breeding in it and not be seen. Some want to say that a toby will carry the gene because it has breeding of a frame overo, yet there has been some finding that tobys that don't have the frame overo gene to carry the lw gene. I have to agree that a lw foal can not survive. You can alot of times get a very white horse by breeding a toby to a overo. Been there done that. This is typical of the two being crossed. I have a mare that produces the sabino gene, most don't think she is regular registry paint. She has only the min spot on her belly that qualifies her as reg. paint and she produces a max white baby every time when breed to a frame overo. the babies have miminal "dark color" , a little around the ears, some fleckling down the back and chest. It is tricky and if you want to know for sure then test everything you breed too. Most larger breeders that I have spoke to seem to not make a difference. If you want that spotted horse, they will take a chance. One large breeder that registers over a hundred colts with apha a year told me that the chance is slim and the people want the spots so that is what they breed for. He forsees no change in the association with testing or requirements with the lw gene. Its there,its part of the game. If you were to start to mandate the breeding requirements of those tested with the lw gene it would elimanate alot of the gene pool, and the association just is not going to do it. We have been breeding paints for about 20 years and never had a lw foal breeding any overos to overos. The best chance to produce lots of color is mixing your patterns and breeding tobys/toveros/overos, including the sabino gene which give you the skunk tail and fleckling type spots.
 

WSTRNPLEASUREPAINTS
Nursing Foal
Username: Jmshowhorses

Post Number: 18
Registered: 05-2010
Posted on Wednesday, June 02, 2010 - 08:57 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

GOSH.... Kristen obviously has the most current facts, why argue them? I have been training APHA colts for 15 years, & we are always finding something new... I am NOT a breeder, but I even know the latest, just read through APHA they will keep you up to date. I couldn't even BELIEVE this thread, & people trying to argue ... She seems to be the most up to date as last I checked. COME ON PEOPLE!GENEOTYPE, & PHENOTYPE... Appearance, and genetic makeup ARE different<>> my 5 yr. old twins know that. I TRULY FEEL FOR ALL APHA BREEDERS I WORK FOR, & think they have & still are doing a WONDERFUL job in creating "PERFECT" COLORED QUARTER HORSES! APHA is about there, or in some opinions IS there ...FINALLY!
 

Diana Gilger
Senior Stallion or Mare
Username: Kdgilger

Post Number: 3446
Registered: 01-2008
Posted on Wednesday, June 02, 2010 - 09:02 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

GOSH is right! You're arguing a thread that is 5 yrs old (speaking of "current facts")! None of those people even post here anymore LOL...and MY 5 yr old knows THAT!
 

WSTRNPLEASUREPAINTS
Nursing Foal
Username: Jmshowhorses

Post Number: 19
Registered: 05-2010
Posted on Wednesday, June 02, 2010 - 09:03 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

LOL, I realized that after I posted, I guess I am bored!LOL... I need to go work my colts, & quite reading threads!LMAO



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