baby color estimation

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In the basic sense, your foal will be born either black, bay or red, possibly with roan.  However, there are a LOT of things going on here that can/will influence the foal's final adult color.

Blue Roan is black based for extension, so E, for sure.  (Red base is ee.)  Is the roan's black base heterozygous eE or homozygous EE?  Blue Roan implies not bay roan, so no agouti aa.

What color was your mare before she turned gray?  Gray covers base color, so was she black, bay or chestnut/sorrel?  You would need to know her genetic makeup for extension, agouti and other modifiers before we could determine foal color.  In addition, is the mare homozygous or heterozygous for gray?  If she is Homzyg, the foal *will* get a gray gene and turn gray.  If she is Het-zyg there is a 50% chance of gray or not gray.

Edited by Heidi n Q

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I'll give you some basic examples.


EEaaRn - Hzyg black, Hzyg no agouti, hetzyg 1 roan  

EeaaRn -  hetzyg extension with 1 black & 1 red, Hzyg no agouti, 1 Rn

* it is believed there are no Hzyg roans and all roans carry only 1 copy of the Rn gene


EEaaGG - Hzyg black, Hzyg no agouti, Hzyg gray (foal will always turn gray)

EeAaGg - 1 black, 1 red, 1 agouti, 1 gray (hetzyg for all genes, 50-50 chance of foal receiving either gene)

eeAAGg - Hzyg red, Hzyg agouti, 1 gray (if foal is black-based, will always be bay because of agouti)


You can see why we need to know the genetic color makeup of both parents before we can give an educated guess.

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From what I can tell, on CBH's dam's side there is a lot of bay, chestnut and gray with no original color designation.  On his sire's side there is black/blue roan and further back are gray, bay, brown (I think that is dark bay) and chestnut/sorrel.  He is black based roan, which means he has no agouti (aa) or he'd be bay.  He is black-based but could be either EE or Ee for the extension gene.  Because he is roan he has the Rn gene and can pass that to his foals.

EeaaRn  or  EEaaRn

With RDR (I like how she is built!), she has a lot of gray and chestnut/sorrel on her sire's side.  Her dam's side is predominantly bay/brown with some chestnut/sorrel.  Her gray comes from her sire's side and not her dam, so she is heterozygous for gray Gg.  Because she has a fair amount of bay/brown on her dam's side, she could be either AA or Aa.  Base color is more difficult to guess, but since she lists chestnut/sorrel on the top side of her sire's line and only grays on the bottom, and chestnut/sorrel and bay on the bottom side of her dam's line, she could be either Ee or ee.

EeAaGg  or   EEAaGg  

EeAAGg  or  EEAaGg


If either Blue or Rainy are EE, the foal will be black based.  If they are both Ee, you could get either black (EE or Ee) or red (ee) based.

Blue has no agouti.  If Rainy's agouti status is AA the foal will be bay.  If her agouti status is Aa, there is a 50% chance the foal will be bay.  If she is red based (unlikely, but still possible) with ee, you could get black Ee or red ee if Blue's extension status is Ee.  Rainy is gray on her top side but not her bottom side so she is heterozygous for gray with Gg and there is a 50% chance the foal will be gray.  Blue is roan so there is a 50% chance the foal will be roan.


It still isn't clear without having genetic testing of both sire and dam - the information in the pedigree is too incomplete.  But if I had to GUESS .... I'd guess she'll have a bay and it could go either way between roan and gray.  I'll hope for bay roan with no gray though there is the possibility of her having a red-based foal in addition to roan and gray modifiers.

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