Looks like Canto might if he filled out. Except take the chain out of his mouth! Seal Brown Thoroughbred. Seal Brown Horses and Dark Bay Horses are extremely hard to tell apart. Here's the hint: Seal Brown horses (like the one in the picture) have chestnut around their muzzles, flanks, and girth; while Dark Brown horses are all brown with black points and NO chestnut markings.