My APHA filly is registered under red dud, but I read in a thread recently that their parents have to be red dun also, her Sire is Palomino Zan Its Yellow Doc, his Sire is Dun Zan It, and his Sire is Dun Hollywood Dun It, her Dam is a sorrel tobiano her sire is brown. So is she red dun or not? She has a dorsal stripe which is about 1/2 - 1 1/2 inch wide all the way down her back.
I would say she is a red dun. If she is then one of her parents DID have to have dun. Either her mother didnt "show her stripe" due to white on her back (i doubt that as tobianos usually don't have white on their backs) or her father was a dunalino which can sometimes be VERY hard to see the dun. Either that or some stallion jumped the fence and her daddy isnt who they say he is! Good luck!
Yes I have other pictures on a different computer and can get more photos tonight while I'm working with her. She likes her picture taken. I thought she was red dun but just wanted to be sure so I didn't look crazy telling people she was red dun and them to be thinking "that girls crazy she isn't red dun". I will post pics of her Knees, Hocks, and Dorsal Stripe tonight.