According to Dr. Karl Miller there is no name for the condition you have seen. He seems to have had a deer like this in his captive herd but it reverted back the normal white-tail color after a couple of years.
No one knows if it could have been dietary, disease of some sort or maybe sunspots...Nevertheless, its really neat to see..
The 11 point in my avatar was strawberry blonde, a lot lighter than any other deer I've ever seen. He was also heavily scared from what appeared to be a mix of close calls with hunters and fights with other deer. I wonder if the wounds have any influence on their coat?
Around here, I have seen brown deer, the color of those in the pics as well as some that are almost red. No doubt the color is different from deer to deer.