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There are four base horse coat colors, black, chestnut, bay and brown. Black, bay and brown coats are caused by the agouti gene and it is the Dominant agouti allele that causes black hairs to be restricted to the points.
Agouti Magic
Seal brown can be subtle and is easily confused with dark bay, especially when there is a pangare modifier involved. Some registries do not consider it a different color, but a shade of bay.
Brown Comparison
Below is a couple comparisons of two animals that are similar in color, but different genetically. In both cases the brown animal is on the right.
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Dark Bay vs. Seal Brown
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Mealy Bay vs. Seal Brown
Seal Brown Characteristics
The only physical way to visually identify a seal brown animal is the varying degrees of lighter, reddish hair found on their soft spots, including muzzle, flank, elbow and belly.
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Seal brown nose
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Seal brown eyes
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Seal brown flank and elbow
Learn More About Color
Be sure to visit the new and improved color section for more information (and pictures) about seal brown horses and stay tuned for more.