# Homozygous Tobiano -- Bear Paw



## Bridgertrot (Dec 2, 2011)

So I'm currently taking an equine genetics class and we were discussing tobiano's. My professor started to talk about how you can generally tell if a tobiano is homozygous due to "bear paw" markings. He asked if anyone knew what it was and nobody was answering, so I responded because I was pretty sure he was referring to the tiny spots of color some tobiano's have a tendency to get. Like such:









I apparently was incorrect. He couldn't describe it so he said he was going to post a picture to our class website so we could look at it. I received an email saying that he can't really find any good pictures. 

He describes it as "Basically, it is described as a "darker roaning" pattern that can show up within the white markings typical to the Tobiano genotype"

Now I just feel like he's just saying how tobiano's have their little roan patches but why would that be so hard to describe? 

Anyway, does anyone who is more versed in these "bear paws" have any good pictures that I can send him?


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## Annanoel (Mar 29, 2011)

I thought that's what bear paws looked like? We called them "puppy paws" too. They CAN be roan spots in my experience, but otherwise they're just spots. My colt Rocky was homozygous for tobiano and he had these as well as the sharks teeth by his feet. 

I'm not really sure what your professor means, and I'd love to see the picture if he can come up with one.


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## TexasBlaze (Oct 4, 2010)

Lil More Conclusive


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## Bridgertrot (Dec 2, 2011)

Annanoel said:


> I thought that's what bear paws looked like? We called them "puppy paws" too. They CAN be roan spots in my experience, but otherwise they're just spots. My colt Rocky was homozygous for tobiano and he had these as well as the sharks teeth by his feet.
> 
> I'm not really sure what your professor means, and I'd love to see the picture if he can come up with one.


See I was 99% sure I was correct. That's why I was like WTF? When he said I was wrong. I question some things about the class. There's a lot of stuff they don't mention and I feel he called some pictures incorrect colors. And he won't talk about brown for some reason.
_Posted via Mobile Device_


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## TexasBlaze (Oct 4, 2010)

Some teachers are just rediculous! I had a teacher tell me once that cremello was deadly and that the AQHA didnt register them. He also expected me to be suprised that greys arent born grey *eyeroll*


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## Annanoel (Mar 29, 2011)

See, that would bother me to no end. I'm in the process of learning colors and gentics too. It only makes it that much more confusing when you have a professor like that, then you question youself and I definitley know how you feel. Brown, brown, brown, lol. 

Bases are black and red, then there are modifiers and so on including brown. Still though, if he is your professor he should be going over it and not avoiding material.


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## Bridgertrot (Dec 2, 2011)

I find myself having to bite my tongue a lot.
_Posted via Mobile Device_


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## Chiilaa (Aug 12, 2010)

"Ink spots" is another term for it. And he is wrong - you cannot tell zygousity of tobiano by looking at the pattern. Yes, ink spots do seem to appear more often on homozygous horses, but they are not on all of them (not even on the majority), and they can be found on heterozygous horses too.


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## lilruffian (Jun 28, 2010)

Chiilaa said:


> "Ink spots" is another term for it. And he is wrong - you cannot tell zygousity of tobiano by looking at the pattern. Yes, ink spots do seem to appear more often on homozygous horses, but they are not on all of them (not even on the majority), and they can be found on heterozygous horses too.


 Precisely. When my aunt first got together with her now-ex-boyfriend who bred Paints, he told her that "bear paw markings" were how you told if a horse was homozygous.:-|
Then when he had a fellow horseperson over one day, she was showing off one of the mares they had and telling him she was homozygous because she had these spots. One look at her pedigree and he knew this was wrong as the mare's sire was a solid Quarter Horse with no specific Paint lineage.


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## Bridgertrot (Dec 2, 2011)

Save me Chiilaa! It hurts to go to that class! xD

Things like when we talked about Champagne...he put up an American Cream Draft picture and I could tell everyone was like "um...how is this any different from a palomino?" He never mentioned anything about mottled skin which is a big giveaway and would clear a lot of things up for the less educated people.

At least though...THANK GOD he keeps repeating that there are no Albino horses. People even keep asking, like dominant white for example, "so...is THIS one an albino then?" He just got done telling you there are none! ARG.

And a side question...is homozygous dominant white lethal? <.<


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## Chiilaa (Aug 12, 2010)

Bridgertrot said:


> And a side question...is homozygous dominant white lethal? <.<


It is believed to be embryonic lethal, yes. This means that a embryo that is WW is not viable, and will terminate. It is not lethal like frame, where the foal is born and then subsequently dies.


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## lovelyStory (Oct 2, 2012)

**sighs**



TexasBlaze said:


> Lil More Conclusive


Oh dear Lord, I have suddenly and forever after fallen in love with THE perfect dream horse. It's almost a religious experience:lol::lol::lol:


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## enh817 (Jun 1, 2012)

Bridgertrot said:


> Save me Chiilaa! It hurts to go to that class! xD
> 
> Things like when we talked about Champagne...he put up an American Cream Draft picture and I could tell everyone was like "um...how is this any different from a palomino?" He never mentioned anything about mottled skin which is a big giveaway and would clear a lot of things up for the less educated people.
> 
> ...



Be glad he at least know that there are no Albino horses. My teacher told us that Cremello was just a made up color that breeders invented so they didn't have to call their horses Albino. He was like "those people breeding buckskins started getting Albino horses. No one wants to buy an Albino horse so they decided to make up a fancy name for them" I tried to explain that it makes tons of sense that the people breeding for buckskin would end up with some Cremello horses and both colors are caused by the cream gene, but he insisted Cremello isn't a real color *headdesk*
My other teacher repeatedly told me I was wrong when I tried to explain the difference between the different Overo patterns. She insisted there is just Tobiano and Overo and told me if I didn't believe her to go try to enter a Paint show (or something) and I'd see that there are only Tobiano and Overo class. 
She also called me out, basically making fun of me for 'not knowing what bay is' because I was calling horses brown, that she considered bay (trust me, they're brown ;D )

Almost makes me want to pay to have a bunch of horses out here tested, just to prove them wrong.
I just let it go though and then post links to accurate information on my facebook so any of my classmate that are interested can educate themselves.


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## SorrelHorse (Apr 9, 2009)

You guys make me never want to take a genetics class.


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## enh817 (Jun 1, 2012)

mine is just a general Horse Evaluation class. Mostly focused on conformation (which thankfully my instructors are pretty well versed in). But we did touch on color briefly. If it were a genetics class I probably would've been more vocal about what I know, but as that isn't the main focus of the class, I didn't really say much.


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## Kayella (Feb 11, 2012)

Maybe he's talking about mapping? Henny has both ink spots and mapping, and I know for a fact he's heterozygous tobiano. He also has some "roaning" on his neck but that's the only place he has it. It's barely noticeable in his winter coat, there's are all from this summer when he was only 4 months old and had just shed out his foal coat. I have heard of people basing mapping on being homozygous for tobiano. But really, there is no phenotypic difference between hetero and **** tobiano, like there is no phenotypic difference between hetero and homozygous black. Henny MAY be homozygous black, but I would have to get him tested.

Side Note: These pictures make me miss my tiny baby!! :-( They grow up so fast.


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## Chiilaa (Aug 12, 2010)

That's the other word that I was looking for! Mapping, another word for haloing, which is the "roaned" ring around a coloured area.


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## Bridgertrot (Dec 2, 2011)

Nope. I brought up mapping to him too and he looked at me like I was crazy. Apparently a lot of people sent him pictures and he said thanks, but he hasn't posted any even though he said he would. I don't think he even knows what he wants. lol


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