# Black Mare & Sorrel Overo Stallion?



## lilruffian (Jun 28, 2010)

My guess, if dam was indeed true black on both sides and sire was sorrel overo would be black, possibly with overo.
Black (correct me if i am wrong everyone) is dominant over red.
As for agouti, the only way to know is by getting the horses tested or knowing for certain than neither parent is bay or brown, which in some circumstances can be tricky if the horse is brown but super darkened to the point where it is hard to tell.


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## lilruffian (Jun 28, 2010)

Oh, and for the horse to me homozygous for anything he/she would have to have it coming from both sides, not just one


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## EnduranceLover6 (Jul 4, 2012)

Yes the mare is a true black and her sire & dam as well. I would be interested to know if anyone can verify if black is a dominant gene over red. Thanks for your answer!


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## Chiilaa (Aug 12, 2010)

EnduranceLover6 said:


> Yes the mare is a true black and her sire & dam as well. I would be interested to know if anyone can verify if black is a dominant gene over red. Thanks for your answer!


Yes black is dominant over red. 

What breed is the mare?

What colour are the sire's grandparents?


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## Tessa7707 (Sep 17, 2012)

Subbing because I'd like to hear what the color experts say. I'm pretty sure the only way to know for sure on the agouti and/or homozygous is to have them tested. Please quickly correct me if I'm wrong.


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## Chiilaa (Aug 12, 2010)

Tessa7707 said:


> Subbing because I'd like to hear what the color experts say. I'm pretty sure the only way to know for sure on the agouti and/or homozygous is to have them tested. Please quickly correct me if I'm wrong.


The mare has to have no agouti to be black, so we can definitely rule it out on her side. The stallion, being red based, can "hide" agouti, since it doesn't do anything to a red based horse.


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## EnduranceLover6 (Jul 4, 2012)

Chiilaa said:


> Yes black is dominant over red.
> 
> What breed is the mare?
> 
> What colour are the sire's grandparents?


The mare is Arabian.

The stallion's grandpartents are sorrel overo and solid sorrel on both the dam and sire's sides. I attached his pedigree in case what I said is confusing. 

Hez Red Hot Paint


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## Chiilaa (Aug 12, 2010)

You would have to test him to check his agouti status. Unfortunately, it can hide on red horses, and since he goes back to horses with agouti in about the 5th gen, there is no way to tell if that agouti is still there.

Has he sired any other foals?


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## EnduranceLover6 (Jul 4, 2012)

Chiilaa said:


> You would have to test him to check his agouti status. Unfortunately, it can hide on red horses, and since he goes back to horses with agouti in about the 5th gen, there is no way to tell if that agouti is still there.
> 
> Has he sired any other foals?


Yes he has sired other foals, but unfortunately I don't know what the mares' colors were. I know he has foaled mostly sorrel overos, however he did foal one solid chestnut.


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## Chiilaa (Aug 12, 2010)

Yup. Would have to test his agouti to know for sure. Could also test the mare to see if she is homozygous for black or not. If she is, it means she can only ever have black based foals, if she is carrying red, she can produce red based foals too.


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## EnduranceLover6 (Jul 4, 2012)

Chiilaa said:


> Yup. Would have to test his agouti to know for sure. Could also test the mare to see if she is homozygous for black or not. If she is, it means she can only ever have black based foals, if she is carrying red, she can produce red based foals too.


If the mare has a chestnut grandparent does that mean that she would be heterozygous? Or can she still be homozygous?


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## Chiilaa (Aug 12, 2010)

EnduranceLover6 said:


> If the mare has a chestnut grandparent does that mean that she would be heterozygous? Or can she still be homozygous?


She could still be homozygous. Her parent that has a chestnut parent would be heterozygous, but she may have gotten the black from that parent rather than the red.


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## EnduranceLover6 (Jul 4, 2012)

I see. Thank you for your knowledge!


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