Deer Supplement?

What is the best mineral/supplement to put weight and nutrients on a deer. I have a young doe hanging around my house that I beleive was hit by a car earlier this year and does not look good. She is going to live but you can see her ribs and she has all the alfalfa she could dream of. So what would supplement her the best for the money. I was thinking about getting a trace mineral block for her. Any thoughts or ideas would be appreciated.

Thanks Brian