Mike, I asked Darryl Coates, Illinois Department of Natural Resources, District Wildlife Biologist, to provide an answer for your question. Here is his response:
Deer will eat oats. However, we may be looking at a killing frost before too long and the results of planting oats will be less that good-- actually very poor. I would recommend rye or winter wheat. Both of these will make great winter forage and will continue to grow through the cold months. Rye should be turned under in the spring. Not many animals will eat rye seed. Rye will make a nice cover crop, winter forage, and a good green manure in the spring. Rye is general cheaper that winter wheat. Good luck.