liquid antibiotic for deer

I have a doe who has been coming for 2 years she has a growth on her back hoof it has grown a little in the two years. she used to come occasionally and eat from bird feeders and compost . I would see her around the area she now comes every day I feed her oats and molasses apples pears and carrots in the morning and Midwestern sweet mix in the evening with Vegis I would like to try an oral antibiotic to see if that might help. she has been limping a little on the leg and now stays pretty close and lives in a dog pen in my back yard the gate is always open. I do not interact with her other than to put her food out and talk to her through the door. not sure how to attach a picture.